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Impact of microfluidic processing on bacterial ribonucleic acid expression

TitleImpact of microfluidic processing on bacterial ribonucleic acid expression
Publication TypeJournal Article
Year of Publication2015
AuthorsGandi, S K., D. E. Watson, M. Kersaudy-Kerhoas, M. P. Y. Desmulliez, T. Bachmann, and H. Bridle
JournalBiomicrofluidics
Volume9
Pagination-
Date Published05/2015
Abstract

Bacterial transcriptomics is widely used to investigate gene regulation, bacterial susceptibility to antibiotics, host-pathogen interactions, and pathogenesis. Transcriptomics is crucially dependent on suitable methods to isolate and detect bacterial RNA. Microfluidics offer ways of creating integrated point-of-care systems, analysing a sample from preparation, and RNA isolation to detection. A critical requirement for on-chip diagnostics to deliver on their promise is that mRNA expression is not altered via microfluidic sample processing. This article investigates the impact of the use of microfluidics upon RNA expression of bacteria isolated from blood, a key step towards proving the suitability of such systems for further development.

URLhttp://scitation.aip.org/content/aip/journal/bmf/9/3/10.1063/1.4921819
DOIhttp://dx.doi.org/10.1063/1.4921819

Simulation of an eddy current based inductive position sensor

TitleSimulation of an eddy current based inductive position sensor
Publication TypeConference Paper
Year of Publication2015
AuthorsGao, J., D. E. Watson, and M. P. Y. Desmulliez
Conference NameRadio {Science} {Conference} ({URSI} {AT}-{RASC}), 2015 1st {URSI} {Atlantic}
URLhttp://dx.doi.org/10.1109/URSI-AT-RASC.2015.7303221
DOI10.1109/URSI-AT-RASC.2015.7303221

Microstructure and electrical property of copper films on a flexible substrate formed by an organic ink with 9.6 % of {Cu} content

TitleMicrostructure and electrical property of copper films on a flexible substrate formed by an organic ink with 9.6 % of {Cu} content
Publication TypeJournal Article
Year of Publication2015
AuthorsYang, W-dong., C-hai. Wang, V. Arrighi, C-yan. Liu, and D. E. Watson
JournalJournal of Materials Science: Materials in Electronics
Volume26
Pagination8973–8982
ISSN1573-482X
Abstract

An organic copper ink with 9.6 wt% of Cu content derived from a short carbon chain organic copper precursor was successfully applied on a modified PI substrate and easily formed a favorable conductive copper film by self-reduction in the sintering process, which showed excellent conductivity. The effects of sintering temperature and time on the microstructure and conductivity action of the copper films were studied by XRD, EDS and SEM and electrical measurements, respectively. The sheet resistance and resistivity were determined to be as low as 0.11 Ω/□ and 2.2 × 10−5 Ω·cm. The conduction mechanism is discussed in terms of the percolation theory.

URLhttp://dx.doi.org/10.1007/s10854-015-3580-4
DOI10.1007/s10854-015-3580-4

Impact of microfluidic processing on bacterial ribonucleic acid expression

TitleImpact of microfluidic processing on bacterial ribonucleic acid expression
Publication TypeJournal Article
Year of Publication2015
AuthorsGandi, S K., D. E. Watson, M. Kersaudy-Kerhoas, M. P. Y. Desmulliez, T. Bachmann, and H. Bridle
JournalBiomicrofluidics
Volume9
Pagination031102
KeywordsRNA
URLhttp://scitation.aip.org/content/aip/journal/bmf/9/3/10.1063/1.4921819

Additive metallisation process

TitleAdditive metallisation process
Publication TypeMiscellaneous
Year of Publication2014
AuthorsNg, J. H. G., D. E. Watson, M. Desmulliez, and D. P. Hand
URLhttps://www.google.com/patents/US20140305791

In-situ Silver Nanoparticle Formation on Surface Modified Polyetherimide Films

TitleIn-situ Silver Nanoparticle Formation on Surface Modified Polyetherimide Films
Publication TypeJournal
Year of Publication2014
AuthorsWatson, D. E., J. Ng, K. Aasmundtveit, and M. Desmulliez
Keywordsannealing, Atmosphere, Ions, nitrogen, Polyimides, silver, Substrates
Abstract

This article extends the scope of a novel process previously reported by the group for the hydrolysis and subsequent metalisation of polyimide substrates to encompass polyetherimide. Silver nanoparticles are grown in-situ by chemical reduction of silver ions implanted in the substrate. Factors affecting the level of hydrolysis are investigated, with temperature of the hydrolysing solution found to be the key factor. The presence of silver nanoparticles is also confirmed by X-ray diffraction.

DOI10.1109/TNANO.2014.2318203

Prognostic Health Management techniques for intelligent condition monitoring of offshore renewable generation assets

TitlePrognostic Health Management techniques for intelligent condition monitoring of offshore renewable generation assets
Publication TypeConference Paper
Year of Publication2013
AuthorsHerd, D. S., and D. Flynn
Conference NameRenewable Power Generation Conference (RPG 2013), 2nd IET
Date PublishedSept
KeywordsCondition Monitoring, Health Management, Prognostics, Sensors
Abstract

The application of Prognostic Health Management (PHM) methods offer the potential of improved reliability in the maintenance of large, remote and complex assets ensuring they continue to achieve optimal performance throughout their designed lifetime. This paper reviews the current state-of-the-art in condition monitoring for the offshore renewable energy sector to highlight the current capabilities and limitations. Based upon this review and an examination of PHM case studies, the design and function of PHM systems for offshore renewable industry assets will be presented.

DOI10.1049/cp.2013.1732

Encapsulation of Microelectronic Components Using Open-Ended Microwave Oven

TitleEncapsulation of Microelectronic Components Using Open-Ended Microwave Oven
Publication TypeJournal Article
Year of Publication2012
AuthorsPavuluri, S. K., M. Ferenets, G. Goussetis, M. P. Y. Desmulliez, T. Tilford, R. Adamietz, G. Muller, F. Eicher, and C. Bailey
JournalComponents, Packaging and Manufacturing Technology, IEEE Transactions on
Volume2
Pagination799 -806
Date Publishedmay
ISSN2156-3950
Keywordsautomatic computer-controlled closed feedback loop, curing, curing material, curing temperature cycle, differential scanning calorimeter, differential scanning calorimetry, encapsulation, encapsulation material, infrared pyrometer, microelectronic component, microwave ovens, open-ended microwave oven, polymer dielectric, polymers, real-time measurement, temperature measurement
Abstract

An open-ended microwave oven system is presented and characterized for the rapid encapsulation of microelectronic components. In situ real-time measurement of the temperature of the curing materials is carried out by an infrared pyrometer integrated in the microwave head of the oven. An automatic computer-controlled closed feedback loop has been used to measure the temperature in the curing material and modulate the system operating power to obtain predefined curing temperature cycles for efficient curing. Uniform curing of the encapsulant material is achieved with typical cure time of  300s with a ramp rate of 1.66 #x00B0;C/s and a hold period of  100s . Differential scanning calorimeter based measurement for the curing of the polymer dielectric indicates a near 100% degree of cure.

DOI10.1109/TCPMT.2011.2177524

Surface embossing of LTCC during the lamination process

TitleSurface embossing of LTCC during the lamination process
Publication TypeConference Paper
Year of Publication2012
AuthorsWilhelm, S., and M. P. Y. Desmulliez
Conference NameDesign, Test, Integration and Packaging of MEMS/MOEMS (DTIP), 2012 Symposium on
Date Published04/2012
Keywordsbump arrays, ceramic packaging, embossing, isostatic lamination, lamination process, laminations, low temperature cofired ceramics technology, LTCC package, microchannels, self constrained ceramics HL2000, structured metal sheet, surface embossing
Abstract

This paper presents an embossing technique that allows a reduction of manufacturing steps by patterning the top and bottom faces of an LTCC package during isostatic lamination using a structured metal sheet. Two examples of micro-channels and bump arrays are presented for self constrained ceramics HL2000.

Novel Patterning Technologies for Ceramic MEMS

TitleNovel Patterning Technologies for Ceramic MEMS
Publication TypeMagazine Article
Year of Publication2012
AuthorsWilhelm, S., Y. Lacrotte, R. W. Kay, and M. P. Y. Desmulliez
MagazineAdvancing Microelectronics
Volume39
Issue Number2
Date Published03/2012
Keywordsceramic, embossing, LTCC, MEMS, microsystems, powder blasting, screen printing, stencil printing
Abstract

Low Temperature Co-fired Ceramic (LTCC) technology is a flexible, high throughput and low cost process used increas- ingly in a wide range of ceramic devices. This paper presents three novel patterning technologies, which employ reusable templates for accurate and high definition patterning. A dry patterning processing using power blasting and a precision template to generate 3D features below 100μm on LTCC are reported. A unique dual layer stencil printing process capable of printing down to 40mm wide lines is also presented. Finally a micro-embossing process, which is integrated into standard MEMS processing steps, is demonstrated. As case studies of these novel patterning two ceramic MEMS devices are fabri- cated: a 6 degree-of-freedom MEMS actuator and a ceramic microfluidic mixer.

Progress towards filling through silicon vias with conductive ink

TitleProgress towards filling through silicon vias with conductive ink
Publication TypeConference Paper
Year of Publication2012
AuthorsCummins, G., J. H. - G. Ng, R. Kay, J. Terry, M. P. Y. Desmulliez, and A. J. Walton
Conference NameEngineering Packaging and Technology Conference (EPTC)
Abstract

Inkjet printing is a promising additive manufacturing technology that is being increasingly used in applications such as displays, electronics and electronic packaging. Through Silicon Vias (TSVs) is an important enabling technology for advanced electronic packaging. The direct write nature of inkjet printing would also allow flexible packaging solutions through the cheap and sustainable filling of vias. This paper describes the progress to date with using this printing technology to fill TSVs and some of the challenges encountered to date.

Inkjet printing of conductive materials: a review

TitleInkjet printing of conductive materials: a review
Publication TypeJournal Article
Year of Publication2012
AuthorsCummins, G., and M. P. Y. Desmulliez
JournalCircuit World
Volume38
Issue4
Pagination193-213

Lamination based embossing technique for LTCC}

TitleLamination based embossing technique for LTCC}
Publication TypeJournal Article
Year of Publication2012
AuthorsWilhelm, S. P., R. W. Kay, M. I. Mohammed, Y. Lacrotte, and M. P. Y. Desmulliez
JournalMicrosystem Technologies

Additive photolithography based process for metal patterning using chemical reduction on surface modified polyimide

TitleAdditive photolithography based process for metal patterning using chemical reduction on surface modified polyimide
Publication TypeConference Paper
Year of Publication2011
AuthorsWatson, D. E., J. H. - G. Ng, and M. P. Y. Desmulliez
Conference NameMicroelectronics and Packaging Conference (EMPC), 2011 18th European
Date Publishedsept.
Keywordsadditive photolithography, biomedical applications, chemical reduction, e-paper bonding applications, electroless plated microstructures, electroless silver plating, electronic devices, flexible electronics, flip-chip bonding applications, metal patterning, nanocluster formation, OLED, photoresists, polyimide direct metallisation, polymer electronics production, reduction (chemical), RFID, semiconductor device metallisation, silver ion impregnation, solvent free photoresist, surface modified polyimide, UV photoreduction experiments
Abstract

This article presents progress towards the direct metallisation of polyimide via silver ion impregnation and nanocluster formation using a novel solvent free photoresist prior to electroless silver plating. Such a process is envisaged to play a major part in the fabrication of a wide range of electronic devices, such as RFID, flexible electronics, biomedical applications, OLED, e-paper and flip-chip bonding applications by providing a quicker, greener and more cost effective methods of polymer electronics production. A new method involving the chemical reduction of silver ions is presented here providing a comparison to previous UV photoreduction experiments, and a further test for electrolessly plated microstructures.

URLhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6142411

Prognostic monitoring of aircraft wiring using electrical capacitive tomography

TitlePrognostic monitoring of aircraft wiring using electrical capacitive tomography
Publication TypeJournal Article
Year of Publication2011
AuthorsMcKenzie, G., and P. Record
JournalReview of Scientific Instruments
Volume82
Pagination124705–124705–7
Abstract

Electrical capacitive tomography (ECT) has been used to monitor sections of aircraft wiring, as a tool for prognostic analysis. To apply the principles of ECT across a cross section of only 4 mm, modification of the basic circuit was required. Additionally, a more novel method of placing the necessary electrodes was needed, this being accomplished by etching them from flexible copper sheeting and wrapping them inside the perimeter of an enclosure. Results showed that at this small scale, it was possible to determine the position of a wire-under-test inside the 4 mm diameter enclosure to about 0.1 mm, and that by measuring capacitance between pairs, it was also possible to determine whether or not the insulation of wire passed between the electrodes was damaged. With more than one wire-under-test present, it was possible to determine whether or not damage was present, and if so, which wire was damaged. By detecting insulation damage in this way, ECT has proven to be a useful tool in prognostic monitoring, helping faults to be found before they become safety-critical onboard an aircraft.

DOI10.1063/1.3672997

On the use of silver nanoparticles for direct micropatterning on polyimide substrates

TitleOn the use of silver nanoparticles for direct micropatterning on polyimide substrates
Publication TypeJournal Article
Year of Publication2011
AuthorsNg, J., D. E. Watson, M. Desmulliez, J. Sigwarth, R. Kay, A. McCarthy, D. Hand, K. Prior, W. Yu, and C. Liu
JournalNanotechnology, IEEE Transactions on
VolumePP
Pagination1
ISSN1536-125X
Abstract

This article proposes a direct micropatterning process based on the growth of photoreduced silver nanoparticles onto polyimide substrates. The silver nanoparticles are found to have sufficient catalytic efficiency for subsequent electroless plating. Characterization of the process indicates that UV energy dose and heat treatment have to be traded off against photo- and thermal degradation of the polymer substrate. Factors affecting the adhesion of the final electroless metal deposit are also discussed.

DOI10.1109/TNANO.2011.2160092

Meso-scale actuator design for the integrated dynamic alignment of a lenslet array within a package

TitleMeso-scale actuator design for the integrated dynamic alignment of a lenslet array within a package
Publication TypeConference Paper
Year of Publication2011
AuthorsWilhelm, S., R. W. Kay, and M. P. Y. Desmulliez
Conference NameDesign, Test, Integration and Packaging of MEMS/MOEMS (DTIP), 2011 Symposium on
Date Published05/2011
Keywordsfocal length, gallium compounds, GaN, III-V semiconductors, integrated dynamic alignment, lenslet array, light emitting diodes, LTCC-process compatible meso-scale actuator, micro-optical components, microactuators, microlens array, microlenses, size 3 mm, size 450 mum, size 5 mm, UV-LED array, wide band gap semiconductors
Abstract

This paper describes the design of an LTCC-process compatible meso-scale actuator for the six degrees of freedom dynamic adjustment of micro-optical components, in particular the alignment of a microlens array on top of a UV-LED array. The lens array is specified to have an active area of 3mm #x00D7; 3mm, the GaN array is 5mm #x00D7; 5mm #x00D7; 450 #x03BC;m. The focal length is 65 #x03BC;m. The actuator must enable the collimation or the focusing of the optical beams emanating from the LED array.

Optimization and characterization of Drop-on-Demand inkjet printing process for platinum organometallic inks

TitleOptimization and characterization of Drop-on-Demand inkjet printing process for platinum organometallic inks
Publication TypeConference Proceedings
Year of Conference2011
AuthorsCummins, G., R. Kay, J. Terry, M. P. Y. Desmulliez, and A. J. Walton
Conference NameEngineering Packaging and Technology Conference (EPTC)
Pagination256 - 261
Abstract

Inkjet printing has been extensively used over the past 30
years in the graphic arts and packaging industries. This
technology involves dispensing accurately positioned droplets
of ink onto a substrate, which then solidifies through the
evaporation of the constituent solvent, the cross-linking of a
polymer or through crystallization. The mask-less, flexible,
rapid and low cost nature of inkjet printing, combined with the
development of a range of functional inks, has led to the
adoption of this technology in system manufacturing. The
SMART Microsystems research project underway at the
Institute for Integrated Systems is investigating the use of this
technique in the rapid customization of CMOS foundry wafers
for More-than-Moore applications.
This paper presents results obtained during the
development and optimization of a drop-on-demand inkjet
printing process for initial batches of platinum organometallic
inks. Drop-on-Demand (DOD) inkjet printing works by
inducing a transient pressure pulse in the ink reservoir through
electrical excitation of either a thermal or piezoelectric
element. The correct implementation of this excitation signal
is necessary to produce a pressure pulse capable of
reproducibly and reliably generating a series of droplets. The
effects of system parameters on the formation of these
droplets are investigated. Methods used to characterize droplet
ejection are also described.

Novel dual layer electroformed stencils for high resolution LTCC circuit manufacture

TitleNovel dual layer electroformed stencils for high resolution LTCC circuit manufacture
Publication TypeConference Proceedings
Year of Conference2011
AuthorsKay, R., G. Cummins, J. Terry, M. P. Y. Desmulliez, and A. J. Walton
Conference NameEngineering Packaging and Technology Conference (EPTC)
Pagination507-512

Effect of Sintering Temperature on the Electrical and Mechanical Properties of Inkjet Printed Organometallic Films

TitleEffect of Sintering Temperature on the Electrical and Mechanical Properties of Inkjet Printed Organometallic Films
Publication TypeConference Proceedings
Year of Conference2011
AuthorsCummins, G., R. Kay, J. Terry, M. P. Y. Desmulliez, and A. J. Walton
Conference NameElectronic Materials and Packaging
Conference LocationKyoto, Japan

Application of Particle Swarm Optimisation to Evaluation of Polymer Cure Kinetics Models

TitleApplication of Particle Swarm Optimisation to Evaluation of Polymer Cure Kinetics Models
Publication TypeJournal
Year of Publication2010
AuthorsTilford, T., M. Ferenets, J. E. Morris, A. Krumme, S. Pavuluri, P. R. Rajaguru, M. P. Y. Desmulliez, and C. Bailey
Other Numbers10.1260/1748-3018.4.1.121
Abstract

A particle swarm optimisation approach is used to determine the accuracy and experimental relevance of six disparate cure kinetics models. The cure processes of two commercially available thermosetting polymer materials utilised in microelectronics manufacturing applications have been studied using a differential scanning calorimetry system. Numerical models have been fitted to the experimental data using a particle swarm optimisation algorithm which enables the ultimate accuracy of each of the models to be determined. The particle swarm optimisation approach to model fitting proves to be relatively rapid and effective in determining the optimal coefficient set for the cure kinetics models. Results indicate that the single-step autocatalytic model is able to represent the curing process more accurately than more complex model, with ultimate accuracy likely to be limited by inaccuracies in the processing of the experimental data.

DOI10.1260/1748-3018.4.1.121

Validation of a blood plasma separation system by biomarker detection

TitleValidation of a blood plasma separation system by biomarker detection
Publication TypeJournal Article
Year of Publication2010
AuthorsKersaudy-Kerhoas, M., D. M. Kavanagh, Resham S. Dhariwal, C. J. Campbell, and M. P. Y. Desmulliez
Issue10
Abstract

A microfluidic system was developed for blood plasma separation at high flow rate. This system uses only hydrodynamic forces to separate plasma from whole blood. The microfluidic network features a series of constrictions and bifurcations to enhance the product yield and purity. A maximum purity efficiency of 100% is obtained on blood with entrance hematocrit level up to 30% with a flow rate of 2 mL h−1. Flow cytometry was performed on the extracted plasma to evaluate the separation efficiency and to assess cell damage. A core target of this study was the detection ofcell-free DNA from the on-chip extracted plasma. To this effect, PCR was successfully carried out off-chip on the cell-free DNA present in the plasma extracted on-chip. A house-keeping gene sequence (GAPDH) was amplified without the need for a purification after the separation, thereby showing the high quality of the plasma sample. The resulting data suggests that the system can be used as a preliminary module of a total analysis system for cell-free DNA detection in human plasma.

Non-contact voltage measurement using electronically varying capacitance

TitleNon-contact voltage measurement using electronically varying capacitance
Publication TypeJournal Article
Year of Publication2010
AuthorsMcKenzie, G., and P. Record
JournalElectronics Letters
Volume46
Pagination214–215
Abstract

A voltage measurement methodology is presented, based on the principle of a vibrating capacitance, but implemented electronically. A transconductor with time-varying gain synthesises the vibrating capacitance, the peak to peak charge current of which changes as different DC voltages are applied to the capacitively coupled input. This technique allows for the non-invasive measurement of DC voltages. Experimental results show that the amplitude of the output signal can indeed be used to determine input voltage, with the response being dependent upon the capacitance values in the circuit and the frequency of a locally applied signal that is independent of the voltage being measured.

Influence of Pulse Reverse Plating on the Properties of Ni-Fe Thin Films

TitleInfluence of Pulse Reverse Plating on the Properties of Ni-Fe Thin Films
Publication TypeJournal Article
Year of Publication2010
AuthorsFlynn, D., and M. P. Y. Desmulliez
JournalMagnetics, IEEE Transactions on
Volume46
Pagination979 -985
Date Publishedapril
ISSN0018-9464
Keywordscoercive force, coercivity, core magnetic material, dc deposition, design of experiment, design of experiments, direct current deposition, DOE, electrical properties, electrical resistivity, electroplating, high switching frequency, iron alloys, magnetic permeability, magnetic properties, magnetic thin films, metallic thin films, nickel alloys, NiFe, PR electroplating, pulse reverse electrodeposition, pulse reverse plating effect, relative permeability, resistivity, saturation flux density, structural properties, thin films
Abstract

NiFe thin films deposited by pulse reverse (PR) electrodeposition are promising candidates for the next generation of core magnetic material to be used in magnetic components operating at high switching frequency. The influence of PR electroplating on the structural, magnetic and electrical properties of NiFe is assessed by means of a design of experiment (DOE). Results are compared to NiFe alloys produced by direct current (dc) deposition from an identical electrolyte. The PR samples exhibit an increase in resistivity and relative permeability by a factor of 2 and 1.5, respectively, in comparison to the dc samples. The coercivity and saturation flux density of the PR samples are reduced by 37% and 5%, respectively.

DOI10.1109/TMAG.2009.2036723

An additive method for photopatterning of metals on flexible substrates

TitleAn additive method for photopatterning of metals on flexible substrates
Publication TypeConference Paper
Year of Publication2010
AuthorsNg, J. H. - G., D. E. Watson, J. Sigwarth, A. McCarthy, H. Suyal, D. P. Hand, T. Y. Hin, and M. P. Y. Desmulliez
Conference Name36th International MATADOR Conference
Date Published09/2010
PublisherSpringer
Conference LocationManchester
ISBN Number9781849964326
Keywords3D manufacturing, direct writing, electroless plating, fine linewidth, flexible circuits, ion-exchange, laser, plastic electronics., polyimide, silver
Abstract

Here we present an additive and cost effective process for plastic electronic manufacturing. Metal tracks are fabricated on polyimide substrates via simple chemical processes combined with direct laser writing or photomask exposure. Laser write speed up to 0.5 m.s-1 and metal track linewidth as low as 5 µm were achieved. Further, this process was easily extended to 3D manufacturing; a helical silver track was written onto a cylindrical substrate. Selective electroless plating was also demonstrated on the photopatterned microstructures which showed promising conductivity close to that of bulk silver metal.

URLhttp://www.ellibs.com/book/9781849964326

Dielectric Ebg Corner Reflector Antenna

TitleDielectric Ebg Corner Reflector Antenna
Publication TypeJournal Article
Year of Publication2010
AuthorsBiancotto, C., and P. Record
JournalJournal of Electromagnetic Waves and Applications
Volume24
Pagination2107–2118
Abstract

In this paper, we present a novel dielectric EBG corner reflector antenna. The reflector is realized using dielectric rods arranged in a square lattice. The influence of reflector width, length and source distance from the corner apex is investigated using a simple two-dimensional antenna model; results are then used to design a three-dimensional antenna. A prototype was build and tested, showing a good agreement between simulations and measurements results: 40% impedance bandwidth is achieved as well as stable radiation patterns with a maximum gain of 13.5 dBi and a front-to-back-ratio greater than 20 dB.

Triangular Lattice Dielectric EBG Antenna

TitleTriangular Lattice Dielectric EBG Antenna
Publication TypeJournal Article
Year of Publication2010
AuthorsBiancotto, C., and P. Record
JournalIeee Antennas and Wireless Propagation Letters
Volume9
Pagination95–98
Abstract

A novel electromagnetic band-gap (EBG) antenna based on a triangular lattice of dielectric rods is presented and analyzed using an in-house developed finite-difference-time-domain software simulator. The design steps and the simulations results are presented, focusing on the design of antenna structures with high directivity patterns on the H-plane. Finally, the measurement results of a set of experiments carried out on a prototype designed and built to operate in the X-band are presented and discussed, showing very good agreement with simulations: 31% fractional bandwidth and an average gain of 11.5 dBi are achieved within the bandwidth with 27 dB front-to-back-ratio in the azimuthal plane.

Reliability improvement of a powder blasting process for micro-machining applications

TitleReliability improvement of a powder blasting process for micro-machining applications
Publication TypeConference Paper
Year of Publication2010
AuthorsLacrotte, Y., S. Wilhelm, and M. P. Y. Desmulliez
Conference NameElectronic System-Integration Technology Conference (ESTC), 2010 3rd
Date Published09/2010
Keywordsdrying, freshly dried powder, micromachining, powder blasting machine, powder technology, re-engineering, reliability, reliability improvement, reverse engineering, size 9 mum
Abstract

The improvement on an existing powder blasting machine is presented and characterised in this paper. The original prototype suffered from irregular powder clogging during real time utilisation, especially with very fine particles. Moreover, the fluctuations of the flow of particle generated were not ideal for micro-machining purposes. We demonstrate that the re-engineering of the original reservoir used with freshly dried powder brings reliability and more consistency in the powder flow rate. This improvement is easy to implement in the original design and does not need to re-engineer the entire machine. For this study, very fine powder with average particle diameter of 9 #x03BC;m was used.

DOI10.1109/ESTC.2010.5642962

High Efficiency Wideband Aperture-Coupled Stacked Patch Antennas Assembled Using Millimeter Thick Micromachined Polymer Structures

TitleHigh Efficiency Wideband Aperture-Coupled Stacked Patch Antennas Assembled Using Millimeter Thick Micromachined Polymer Structures
Publication TypeJournal Article
Year of Publication2010
AuthorsPavuluri, S. K., C. Wang, and A. J. Sangster
JournalAntennas and Propagation, IEEE Transactions on
Volume58
Pagination3616 -3621
Date Publishednov.
ISSN0018-926X
Keywords3D devices, air gaps, antenna feeds, antenna structures, aperture antennas, aperture coupled devices, assembling, assembly processes, broadband antennas, CPW fed device, electromagnetic simulation package, high efficiency wideband aperture-coupled stacked patch antennas, impedance matching, LCP, liquid crystal polymers, micromachined stacked patch antenna devices, micromachining, microstrip antennas, microstrip fed antenna device, microwave substrate, millimeter thick micromachined polymer structures, parasitic patch elements, polyimide substrates, polymer based fabrication, polymer structure, RF measurements, stacked suspended antenna devices, SU8 based polymer rings, thin film liquid crystal polymer, thin films
Abstract

Micromachined stacked patch antenna devices with high efficiency and wideband characteristics are reported. Polymer based fabrication and assembly processes have been developed in order to produce the stacked suspended antenna devices. Millimeter thick micromachined SU8 based polymer rings are used to create air gaps between the patches and the microwave substrate for optimized high efficiency operation. Thin film liquid crystal polymer (LCP) and polyimide substrates are used to support the radiating and parasitic patch elements. The polymer rings also form cavities to protect the patches and substrate from moisture and dust. The antenna structures are fabricated in layers and then assembled to obtain 3D devices. The antenna devices have been designed using an electromagnetic simulation package. The aperture coupled devices are impedance matched for wideband operation. RF measurements show wideband operation of the devices and the results are in good agreement with that of simulation. Typical gain and bandwidths are 7.8 dBi and 39% for a microstrip fed antenna device while they are 7.6 dBi and 44% for a CPW fed device. The predicted efficiency from the results of simulation is above 97% for the antenna devices.

DOI10.1109/TAP.2010.2071334

Label-free chemical/biochemical sensing device based on an integrated microfluidic channel within a waveguide resonator

TitleLabel-free chemical/biochemical sensing device based on an integrated microfluidic channel within a waveguide resonator
Publication TypeConference Paper
Year of Publication2010
AuthorsMcKeever, E., S. K. Pavuluri, R. Lopez-Villarroya, G. Goussetis, D. M. Kavanagh, M. I. Mohammed, and M. P. Y. Desmulliez
Conference NameElectronic System-Integration Technology Conference (ESTC), 2010 3rd
Date Publishedsept.
Keywordsbiosensors, chemical sensors, chemical substances, integrated microfluidic channel, Label-free chemical-biochemical sensing device, low temperature cofired ceramic integration scheme, microfluidics, microsensors, microwave resonator, resonators, waveguide resonator
Abstract

In this article we propose a novel label-free chemical/biochemical sensing device based on a waveguide resonator with an integrated microfluidic channel. This device is intended for the characterisation and detection of cells and various chemical substances from within a variety of micro-litre test samples. This paper outlines the design of the prototype device and describes the fabrication of the microfluidic network and microwave resonator. Initial testing of the prototype at X-band is examined with promising results. Finally, we propose a Low Temperature Co-fired Ceramic (LTCC) integration scheme for the miniaturization of the device for use in the THz regime.

DOI10.1109/ESTC.2010.5642874

Experimental investigation of open-ended microwave oven assisted encapsulation process

TitleExperimental investigation of open-ended microwave oven assisted encapsulation process
Publication TypeConference Paper
Year of Publication2010
AuthorsPavuluri, S. K., M. Ferenets, G. Goussetis, M. P. Y. Desmulliez, T. Tilford, R. Adamietz, G. Muller, F. Eicher, and C. Bailey
Conference NameElectronic System-Integration Technology Conference (ESTC), 2010 3rd
Date Publishedsept.
Keywordsassisted encapsulation process, automatic computer controlled closed feedback loop, curing material, curing temperature cycles, differential scanning calorimeter, electromagnetic lossy materials, EM fields, encapsulation, evanescent region forming, fibre optic sensors, IR pyrometer, microwave components, microwave ovens, open ended microwave oven, polymer dielectric, power conversion efficiency, pyrometers, temperature measurement, temperature sensors, time 270 s
Abstract

An open ended microwave oven is presented with improved uniform heating, heating rates and power conversion efficiency. This next generation oven produces more uniform EM fields in the evanescent region forming part of the heating area of the oven. These fields are vital for the rapid and uniform heating of various electromagnetically lossy materials. A fibre optic temperature sensor and an IR pyrometer are used to measure in situ and in real-time the temperature of the curing materials. An automatic computer controlled closed feedback loop measures the temperature in the curing material and drives the microwave components to obtain predetermined curing temperature cycles for efficient curing. Uniform curing of the lossy encapsulants is achieved with this oven with typical cure cycle of 270 seconds with a ramp rate of 1 #x00B0;C/s and a hold period of 2 minutes. Differential scanning calorimeter based measurement for the pulsed microwave based curing of the polymer dielectric indicates a   100% degree of cure.

DOI10.1109/ESTC.2010.5643015

Fabrication of a Polymeric Optical Waveguide-On-Flex Using Electrostatic-Induced Lithography

TitleFabrication of a Polymeric Optical Waveguide-On-Flex Using Electrostatic-Induced Lithography
Publication TypeJournal Article
Year of Publication2010
AuthorsHin, T Y., C. Liu, P. P. Conway, W. Yu, S. Cargill, and M. P. Y. Desmulliez
JournalPhotonics Technology Letters, IEEE
Volume22
Pagination957 -959
Date Publishedjuly1,
ISSN1041-1135
Keywordsabsorption, electrohydrodynamics, electrostatic field-induced self assembly, electrostatic-induced lithography, micro-optics, microfabrication, multimode waveguides, optical arrays, optical core microstructures, optical fabrication, optical film, optical films, optical losses, optical polymer, optical polymers, optical waveguide-on-flex, optical waveguides, pattern formation, photolithography, propagation loss, refractive index, replica techniques, self-assembly, sidewall roughness, size 10 mm, size 50 mum, spin coating, surface electrohydrodynamics instability patterning
Abstract

A method has been developed for the manufacture of polymeric multimode waveguides using an electrostatic field-induced self assembly and pattern formation process. A spin-coated liquid optical polymer placed between two conductive plates experiences an electrostatic force from an applied electric field gradient across the plates. Surface electrohydrodynamics instability patterning is employed to fabricate optical core microstructures using a patterned master plate. The result shows a good replication of the pattern from the master plate to the optical polymer. The process protocols were defined to achieve waveguides with low sidewall roughness together with an optical coupling interface. We have demonstrated multimode waveguide arrays with a 50 #x03BC;m #x00D7; 50 #x03BC;m cross section and 250- #x03BC;m pitch on a 10 mm #x00D7; 10 mm flexible substrate. The refractive index and absorption measurement of the electrostatic-induced optical film show insignificant changes when compared with the unexposed film. Using the cutback approach, the propagation loss of the waveguide is measured at -1.97 dB/cm. The whole fabrication process is found to be fast, cost-effective, and no photosensitive material is needed as in the conventional photolithography approach.

DOI10.1109/LPT.2010.2048310

Numerical analysis of microwave underfill cure in ball-grid packages

TitleNumerical analysis of microwave underfill cure in ball-grid packages
Publication TypeConference Paper
Year of Publication2010
AuthorsTilford, T., M. Ferenets, R. Adamietz, S. K. Pavuluri, J. E. Morris, M. P. Y. Desmulliez, and C. Bailey
Conference NameElectronic System-Integration Technology Conference (ESTC), 2010 3rd
Date Publishedsept.
Keywordsassembling, ball grid array package, ball grid arrays, ball-grid packages, conformal finite difference time domain electromagnetic solver, curing, curing process, dual section microwave oven system, Eulerian-Lagrangian mapping process, finite difference time-domain analysis, finite volume methods, finite volume thermophysical solver, individual surface mount components, integrated circuit packaging, measuring key process parameters, microelectronics manufacturing line, microwave cure, microwave ovens, microwave power density, microwave underfill cure, multiphysics analysis approach, numerical analysis, printed circuit board assembly, printed circuit manufacture, surface mount technology, thermomechanical stress development, thermomechanical treatment, thermosetting polymer underfill material
Abstract

Microwave cure of thermosetting polymer underfill material in a simplified ball grid array package is assessed using a multiphysics analysis approach. A dual section microwave oven system capable of heating individual surface mount components on a printed circuit board assembly is described and its integration into a microelectronics manufacturing line is briefly outlined. Due to the complexity of measuring key process parameters in situ, a numerical approach, briefly described in this article, has been adopted to analyse and optimise the curing process. The numerical model comprises an unstructured finite volume thermophysical solver that is linked, through a Eulerian-Lagrangian mapping process, to a conformal finite difference time domain electromagnetic solver. A sample analysis focusing on the curing of an underfill material in a simplified ball grid array package is considered. Results obtained for a range of temperatures, microwave power density and thermomechanical stress development are presented.

DOI10.1109/ESTC.2010.5642822

On model fitting methods for modeling polymer cure kinetics in microelectronics assembly applications

TitleOn model fitting methods for modeling polymer cure kinetics in microelectronics assembly applications
Publication TypeConference Paper
Year of Publication2010
AuthorsTilford, T., J. E. Morris, M. Ferenets, P. R. Rajaguru, S. K. Pavuluri, M. P. Y. Desmulliez, and C. Bailey
Conference NameElectronic System-Integration Technology Conference (ESTC), 2010 3rd
Date Publishedsept.
Keywordsactivation energy, adhesives, assembling, differential scanning calorimetry, differential scanning calorimetry analysis, integrated circuits, isotropic conductive adhesive material, microelectronics assembly, model fitting method, particle swarm optimisation, particle swarm optimization fitting method, polymer cure kinetics modeling, polymers
Abstract

This work assesses the accuracy of specific numerical models in predicting the cure kinetics of a commercially available isotropic conductive adhesive material. A series of Differential Scanning Calorimetry (DSC) analyses have been performed on the materials to determine fundamental cure data. Cure models have been fitted to these experimental data using both the traditional and Particle Swarm Optimization (PSO) fitting methods. The traditional model fitting approach indicates a significant variation in the activation energy during the cure process. The particle swarm optimization fitting method is able to provide coefficient sets for all cure models assessed. Results obtained with these models are in relatively good agreement with experimental data.

DOI10.1109/ESTC.2010.5642820

Advances in the design and test of a novel open ended microwave oven

TitleAdvances in the design and test of a novel open ended microwave oven
Publication TypeConference Paper
Year of Publication2010
AuthorsPavuluri, S. K., T. Tilford, G. Goussetis, M. P. Y. Desmulliez, M. Ferenets, R. Adamietz, F. Eicher, and C. Bailey
Conference NameDesign Test Integration and Packaging of MEMS/MOEMS (DTIP), 2010 Symposium on
Date Publishedmay
Keywordsautomatic computer controlled closed feedback loop, curing, curing material, dielectric materials, differential scanning calorimeter, differential scanning calorimetry, electromagnetic fields, electromagnetically lossy material, EM field, fibre optic sensors, fibre optic temperature sensor, forming, heating area, heating rate, lossy encapsulant, micromechanical devices, microwave component, microwave ovens, open ended microwave oven, open ended waveguide cavity oven, polymer dielectric, power conversion efficiency, pulsed microwave based curing, uniform curing, uniform heating, waveguides
Abstract

An enhanced open ended waveguide cavity oven is presented with improved uniform heating, heating rates and power conversion efficiency. This next generation oven produces more uniform EM fields in the evanescent region forming part of the heating area of the oven. These fields are vital for the rapid and uniform heating of various electromagnetically lossy materials. A fibre optic temperature sensor is used to measure in situ and in real-time the temperature of the curing materials. An automatic computer controlled closed feedback loop measures the temperature in the curing material and drives the microwave components to obtain predetermined curing temperature cycles for efficient curing. Uniform curing of the lossy encapsulants is achieved with this oven with typical cure cycle of 270 seconds with a ramp rate of 1 #x00B0;C/s and a hold period of 2 minutes. Differential scanning calorimeter based measurement for the pulsed microwave based curing of the polymer dielectric indicates an 98% degree of cure.

On the integration of microwave curing systems into microelectronics assembly processes

TitleOn the integration of microwave curing systems into microelectronics assembly processes
Publication TypeConference Paper
Year of Publication2010
AuthorsAdamietz, R., G. Mü andller, N. Othman, F. Eicher, T. Tilford, M. Ferenets, S. K. Pavuluri, M. P. Y. Desmulliez, and C. Bailey
Conference NameElectronic System-Integration Technology Conference (ESTC), 2010 3rd
Date Publishedsept.
Keywordsassembling, curing, electronics packaging, embedded microwave curing system, encapsulant material, flip-chip, flip-chip devices, integrated circuits, integrated system, microelectronics assembly process, microelectronics packaging, microwave energy, microwave ovens, microwave-assisted assembly, open-ended microwave oven, polymers, precision placement machine, thermosetting polymer curing, thermosetting polymer material
Abstract

In microelectronics packaging applications a variety of thermosetting polymer materials is applied. Such materials are dispensed in a liquid form and are heated with the intent to cure them. Conventional processes often take several hours to bring the material up to temperatures which result in a significant rate of cure. An alternative approach to curing thermosetting polymers is the use of microwave energy, which has been shown to cure encapsulant materials in substantially shorter times. A recent innovation is the open-ended microwave oven proposed by Sinclair et al.. This paper deals with the implementation of the open-ended microwave oven into a precision placement machine. Two test products for encapsulation and flip-chip serve as objective for microwave-assisted assembly. An integrated system setup including the open ended oven is presented. Modifications on the open-ended microwave oven are described and a concept for the development of an embedded microwave curing system is presented. Tests on curing encapsulant materials dispensed over a commercially available QFN were performed to determine post-process functionality of the package, with no evident detrimental effects.

DOI10.1109/ESTC.2010.5642827

Fabrication and Characterization of a Low-Cost, Wafer-Scale Radial Microchannel Cooling Plate

TitleFabrication and Characterization of a Low-Cost, Wafer-Scale Radial Microchannel Cooling Plate
Publication TypeJournal Article
Year of Publication2009
AuthorsDesmulliez, M. P. Y., A. J. Pang, M. Leonard, R. S. Dhariwal, W. Yu, E. Abraham, G. Bognar, A. Poppe, G. Horvath, Z. Kohari, M. Rencz, D. R. Emerson, R. W. Barber, O. Slattery, F. Waldron, and N. Cordero
JournalComponents and Packaging Technologies, IEEE Transactions on
Volume32
Pagination20 -29
Date Publishedmarch
ISSN1521-3331
Keywordsforced convection, heat transfer coefficient, integrated circuit packaging, LIGA, microchannel flow, microelectronic packaging, microfabrication, nickel, nickel-based plate, partial thermal resistance measurement, size 100 mum, size 70 mum, thermal behavior, thermal management (packaging), thermal resistance, two-layer electroforming process, UV-LIGA technology, wafer-scale radial microchannel cooling plate
Abstract

The modeling, simulation, fabrication, and testing of a microchannel cooling plate for microelectronic packaging applications are described in this paper. The cooling component uses forced convection of gas injected inside 128 microchannels of 100-mu m width and 70-mu m height. The nickel-based plate is fabricated on a glass substrate using a two-layer electroforming process using UV-LIGA technology. The thermal behavior of the microchannel cooling device is investigated by using the measurement of partial thermal resistances through the use of the structure functions method. Heat transfer coefficient values of 300 W/m2 K have been measured for a nitrogen flow rate of 120 l/h.

DOI10.1109/TCAPT.2008.2002434

Design, Fabrication, and Characterization of Flip-Chip Bonded Microinductors

TitleDesign, Fabrication, and Characterization of Flip-Chip Bonded Microinductors
Publication TypeJournal Article
Year of Publication2009
AuthorsFlynn, D., and M. P. Y. Desmulliez
JournalMagnetics, IEEE Transactions on
Volume45
Pagination3055 -3063
Date Publishedaug.
ISSN0018-9464
Keywordscobalt-iron-copper alloys, CoFeCo, electrodeposition, flip-chip bonded microinductors, flip-chip devices, frequency 0.5 MHz to 10 MHz, inductors, magnetic core materials, magnetic cores, nickel-iron, NiFe, solenoid microinductor, solenoids, Vitrovac 6025
Abstract

Magnetic core materials of higher performance than ferrite materials in the 0.5-10 MHz frequency range are investigated. The performance characteristics of electrodeposited nickel-iron, cobalt-iron-copper alloys, and the commercial alloy Vitrovac 6025 have been assessed through their inclusion within a custom made solenoid micro-inductor. Inductance values ranging from 0.3 to 120 muH with component power efficiency above 90% have been measured. Two highly laminated prototypes consisting of 70 and 105 laminates of 5 mum thick nickel-iron have achieved a power output efficiency of 92% at 0.5 MHz with power densities of 33 and 49 W/cm3 , respectively. A design methodology based on material properties and device specifications is proposed for the manufacture of performant microinductors. Issues surrounding micro-inductor design and performance are discussed.

DOI10.1109/TMAG.2009.2016558

Mechanically steerable dielectric fluid antenna

TitleMechanically steerable dielectric fluid antenna
Publication TypeJournal Article
Year of Publication2009
AuthorsFayad, H., and P. Record
JournalAeu-International Journal of Electronics and Communications
Volume63
Pagination506–512
Abstract

A heterogeneous dielectric resonator antenna (h-DRA) capable of beam steering is presented. It is been shown that the far-field radiation pattern of dielectric resonator antenna (DRA) can be redirected by manipulating the regional dielectric properties of the antenna. The physical antenna resonated at approximate to 1.2 GHz and measurements were in agreement with simulation. Although work was done using liquid dielectrics, this type of antenna will work equally well when fabricated from machined solid dielectrics. (C) 2008 Elsevier GmbH. All rights reserved.

Beam forming dielectric cylindrical EBG antenna

TitleBeam forming dielectric cylindrical EBG antenna
Publication TypeConference Paper
Year of Publication2009
AuthorsBiancotto, C., and P. Record
Conference NameAntennas {&} Propagation Conference, 2009. LAPC 2009. Loughborough
Abstract

The design steps for a novel cylindrical electronic bandgap antenna in the X-band are given. Simulation results, based on a FDTD modeller are also presented as an aid to designing the physical antenna. The antenna demonstrated high directivity in the H-plane. Measurements on a prototype achieved 54% fractional bandwidth with an average gain of 8 dBi and 17.5 dB front to back ratio in the azimuthal plane.

Design of a beam forming dielectric cylindrical EBG antenna,

TitleDesign of a beam forming dielectric cylindrical EBG antenna,
Publication TypeJournal Article
Year of Publication2009
AuthorsBiancotto, C., and P. Record
JournalProgress In Electromagnetics Research B
Volume18
Pagination327–346
Abstract

A novel dielectric cylindrical electronic bandgap antenna is presented and analysed using an in-house developed Finite-Difference-Time-Domain software simulator. The design steps and the simulations results of a geometrical parametric study are also presented and discussed, focusing on the design of antennas to operate in the X-band with high directivity patterns on the H-plane. Finally, the measurements results of a set of experiments carried out on a prototype showed very good agreement with simulations: 11% fractional bandwidth at 10 GHz and an average gain of 9.5 dBi are achieved in the impedance bandwidth with 13 dB front-to-back-ratio in the azimuthal plane.

URLhttp://www.jpier.org/pierb/pier.php?paper=09101506
DOI10.2528/PIERB09101506

Failure mechanisms of legacy aircraft wiring and interconnects

TitleFailure mechanisms of legacy aircraft wiring and interconnects
Publication TypeJournal Article
Year of Publication2008
AuthorsMoffat, B. G., E. Abraham, M. P. Y. Desmulliez, D. Koltsov, and A. Richardson
JournalDielectrics and Electrical Insulation, IEEE Transactions on
Volume15
Pagination808 -822
Date Publishedjune
ISSN1070-9878
Keywordsaircraft testing, arcs (electric), contact fretting, electric connectors, failure analysis, failure modes effects and analysis, interconnect degredation, legacy aircraft wiring, wiring
Abstract

This paper presents a comprehensive list of the causes and modes of failure and ageing in legacy aircraft wiring and interconnects. Taxonomies of the electrical, mechanical, chemical and thermal stresses that contribute to the various stages of ageing and/or failure are presented. A failure modes effects and analysis (FMEA) is conducted to categorize the most serious failures. The order of severity in the FMEA is backed up by maintenance data gathered by the Royal Air Force (RAF) base Brize Norton during routine inspection.

DOI10.1109/TDEI.2008.4543119

Fabrication and assembly of high gain MEMS antennas for wireless communications

TitleFabrication and assembly of high gain MEMS antennas for wireless communications
Publication TypeConference Paper
Year of Publication2008
AuthorsWang, C. H., and S. K. Pavuluri
Conference NameElectronic Components and Technology Conference, 2008. ECTC 2008. 58th
Date Publishedmay
Keywords3D antenna device, assembly processes, electromagnetic simulation package, high gain MEMS antennas, microassembling, micromachined SU8 polymer ring spacers, micromachining, micromechanical devices, microstrip antennas, microwave substrate, polymer based fabrication, polymers, radiocommunication, RF measurements, size 125 mum, stacked high gain patch antenna devices, wireless communications
Abstract

Polymer based fabrication and assembly processes for producing suspended antenna devices have been developed. Stacked high gain patch antenna devices have been assembled using millimeter thick micromachined SU8 polymer ring spacers. Thin polyimide substrates (125 mum) were used for supporting the radiating and parasitic patch elements. The SU8 based polymer rings were used to create air space between the patches and the microwave substrate for high gain wide band operation. The polymer rings also form cavities to protect the patches and substrate from moisture and particles. An aperture coupled stacked patch antenna consisting of two patch elements was designed using an electromagnetic simulation package. The antenna device was fabricated in layers and then assembled to obtain a 3D antenna device. The detailed fabrication and assembly processes was described. RF measurements showed high gain wide band operation of the device and the results are in good agreement with that of simulation. The average gain and the bandwidth of the antenna device were determined to be 7.2 dBi and -40% respectively.

DOI10.1109/ECTC.2008.4550248

Megasonic enhanced electrodeposition

TitleMegasonic enhanced electrodeposition
Publication TypeConference Paper
Year of Publication2008
AuthorsKaufmann, J., M. P. Y. Desmulliez, and D. Price
Conference NameDesign, Test, Integration and Packaging of MEMS/MOEMS, 2008. MEMS/MOEMS 2008. Symposium on
Date Publishedapril
Keywordsdiffusion, electrodeposition, high-frequency acoustic streaming, interconnections, megasonic enhanced electrodeposition, metal-based MEMS, micromechanical devices, microvias, Nernst-diffusion layer, thermomagnetic effects, vertical interconnection
Abstract

A novel way of filling high aspect ratio vertical interconnection (microvias) is presented. High frequency acoustic streaming at megasonic frequencies enables the decrease of the Nernst-diffusion layer down to the sub-micron range, allowing thereby conformal electrodeposition in deep grooves. Higher throughput and better control over the deposition properties are therefore possible for the manufacturing of interconnections and metal-based MEMS.

DOI10.1109/DTIP.2008.4753020

Open-ended microwave oven for flip-chip assembly

TitleOpen-ended microwave oven for flip-chip assembly
Publication TypeJournal Article
Year of Publication2008
AuthorsSangster, A. J., K. I. Sinclair, M. P. Y. Desmulliez, and G. Goussetis
JournalMicrowaves, Antennas Propagation, IET
Volume2
Pagination53 -58
Date Publishedfebruary
ISSN1751-8725
Keywordscavity resonators, end-fed probes, flip-chip assembly, flip-chip devices, heat sensitive film, low power tests, low-loss dielectric, microwave curing, microwave ovens, open-ended microwave oven, relative permittivity, surface mount technology, wafer level packaging, wafer scale level packaging, waveguide cavity resonator, waveguides
Abstract

A novel open-ended waveguide cavity resonator for the microwave curing of bumps, underfills and encapsulants is described. The open oven has the potential to provide fast alignment of devices during flip-chip assembly, direct chip attach, surface mount assembly or wafer-scale level packaging. The prototype microwave oven was designed to operate at X-band for ease of testing, although a higher frequency version is planned. The device described in the paper takes the form of a waveguide cavity resonator. It is approximately square in cross-section and is filled with a low-loss dielectric with a relative permittivity of 6. It is excited by end-fed probes in order to couple power preferentially into the TM3,3,k mode with the object of forming nine 'hot-spots' in the open end. Low power tests using heat sensitive film demonstrate clearly that selective heating in multiple locations in the open end of the oven is achievable.

DOI10.1049/iet-map:20060316

Conical steerable dielectric resonator antenna

TitleConical steerable dielectric resonator antenna
Publication TypeJournal Article
Year of Publication2008
AuthorsBiancotto, C., and P. Record
JournalElectronics Letters
Volume44
Pagination1107–1108
Abstract

A conical steerable dielectric resonator antenna is presented and analysed using an in-house developed FDTD simulator. A 30% impedance bandwidth is achieved with an average gain of 6.5 dBi. Radiation patterns in the principal planes do not change significantly within the impedance bandwidth, presenting more than 18 dB front-to-back ratio in the azimuthal plane.

Recent advances in microparticle continuous separation

TitleRecent advances in microparticle continuous separation
Publication TypeJournal Article
Year of Publication2008
AuthorsKersaudy-Kerhoas, M., R. Dhariwal, and M. P. Y. Desmulliez
JournalNanobiotechnology, IET
Volume2
Pagination1 -13
Date Publishedmarch
ISSN1751-8741
Keywordsbiological techniques, bioMEMS, cell studies, cellular biophysics, electrical methods, fluidic-only methods, magnetic methods, magnetic separation, microchannel flow, microchannels, micron-sized particle separation, microparticle continuous separation, microsystems, minor separation methods, optical methods, particle size, radiation pressure
Abstract

Recent advances in microparticle separation in continuous flow are presented. It is intended for scientists in the field of separation science in biology, chemistry and microsystems engineering. Recent techniques of micron-sized particle separation within microsystems are described with emphasis on five different categories: optical, magnetic, fluidic-only, electrical and minor separation methods. Examples from the growing literature are explained with insights on separation efficiency and microengineering challenges. Current applications of the techniques are discussed.

DOI10.1049/iet-nbt:20070025

Ultra-violet direct patterning of metal on polyimide

TitleUltra-violet direct patterning of metal on polyimide
Publication TypeJournal Article
Year of Publication2008
AuthorsNg, J. H. - G., M. P. Y. Desmulliez, K. A. Prior, and D. P. Hand
JournalMicro Nano Letters, IET
Volume3
Pagination82 -89
Date Publishedseptember
ISSN1750-0443
Keywordsactive catalytic seed layers, air atmosphere, catalysis, copper, copper micropatterns, Cu, electroless copper plating, electroless deposition, electroplating, ethanol film, integrated circuit metallisation, light-directed metal-patterning, metal, methoxy poly(ethylene glycol), nanoparticle patterns, nanoparticles, nanopatterning, photoreactive polymer-reducing agent, photoreduction, polyimide, polyimide substrates, selective metallisation, surface-modified polyimide substrates, thin film coating, ultraviolet direct patterning, ultraviolet lithography
Abstract

Copper micro-patterns have been fabricated on polyimide substrates by ultra-violet (UV) lithography without the use of evaporation techniques or photoresist materials. Using a photoreactive polymer-reducing agent, methoxy poly(ethylene glycol) (MPEG) as a thin film coating, a novel light-directed metal-patterning method in air atmosphere was realised. The interaction of UV light and MPEG in ethanol film enabled the photoreduction of mobile silver ions available within the surface-modified polyimide substrates. The silver nanoparticle patterns thus formed served as active catalytic seed layers for subsequent electroless copper plating. Narrow copper tracks with low resistivity close to that of bulk copper were achieved. MPEG is a non-toxic, low cost and commercially available polymer which can be easily spin-coated and washed off after the patterning process. These attractive properties of MPEG together with its photoreactivity provide great potential for developments of UV direct-metallisation methods.

DOI10.1049/mnl:20080017

A High-Performance Aperture-Coupled Patch Antenna Supported by a Micromachined Polymer Ring

TitleA High-Performance Aperture-Coupled Patch Antenna Supported by a Micromachined Polymer Ring
Publication TypeJournal Article
Year of Publication2008
AuthorsPavuluri, S. K., C. H. Wang, and A. J. Sangster
JournalAntennas and Wireless Propagation Letters, IEEE
Volume7
Pagination283 -286
ISSN1536-1225
Keywordsantenna feeds, aperture-coupled antennas, aperture-coupled high-gain microstrip patch antenna, micromachined polymer ring, microstrip antennas, microstrip feed line, microstrip lines, microwave PCB substrate, photolithography, photolithography technique, polyimide substrates, slot antennas, slot-coupled antenna device
Abstract

An aperture-coupled high-gain microstrip patch antenna with wide bandwidth is reported. The slot-coupled antenna device was produced on a microwave PCB substrate with a suspended patch supported by a micromachined polymer ring structure. After the fabrication of the microstrip feed line and the coupling slot on the substrate and the patch on a polyimide film, two polymer rings of identical design were deposited on the microwave and the polyimide substrates respectively using a SU8 epoxy resin and the photolithography technique. The two polymer rings were then aligned and bonded together to obtain a suspended patch antenna for high-gain operation. The resultant height of the SU8 ring and hence the gap between the polymer and the microwave substrates was 1.5 mm. Reflection and radiation measurements were carried out to evaluate the performance of the antenna device. The results show that the device has a gain of 8.3 dBi at  12 GHz and a -10 dB bandwidth of  2.5 GHz or 19%. The simulated results are demonstrated to be in good agreement with measurement. The predicted efficiency of the device is about 98%.

DOI10.1109/LAWP.2008.928468

Optimization of an Open-Ended Microwave Oven for Microelectronics Packaging

TitleOptimization of an Open-Ended Microwave Oven for Microelectronics Packaging
Publication TypeJournal Article
Year of Publication2008
AuthorsSinclair, K. I., G. Goussetis, M. P. Y. Desmulliez, A. J. Sangster, T. Tilford, C. Bailey, and A. K. Parrott
JournalMicrowave Theory and Techniques, IEEE Transactions on
Volume56
Pagination2635 -2641
Date Publishednov.
ISSN0018-9480
Keywordsbelow cutoff heating chamber, curing, magnetic resonance, microelectronics packaging, microwave curing, microwave ovens, open-ended microwave oven, optimisation, optimization, resonant cavity, transverse magnetic resonance, waveguide resonator
Abstract

A physically open, but electrically shielded, microwave open oven can be produced by virtue of the evanescent fields in a waveguide below cutoff. The below cutoff heating chamber is fed by a transverse magnetic resonance established in a dielectric-filled section of the waveguide exploiting continuity of normal electric flux. In order to optimize the fields and the performance of the oven, a thin layer of a dielectric material with higher permittivity is inserted at the interface. Analysis and synthesis of an optimized open oven predicts field enhancement in the heating chamber up to 9.4 dB. Results from experimental testing on two fabricated prototypes are in agreement with the simulated predictions, and demonstrate an up to tenfold improvement in the heating performance. The open-ended oven allows for simultaneous precision alignment, testing, and efficient curing of microelectronic devices, significantly increasing productivity gains.

DOI10.1109/TMTT.2008.2005925

Wideband dielectric resonator antenna with reconfigurable radiation pattern

TitleWideband dielectric resonator antenna with reconfigurable radiation pattern
Publication TypeJournal Article
Year of Publication2007
AuthorsFayad, H., and P. Record
JournalNASA/ESA Conference on Adaptive Hardware and Systems, Proceedings
Pagination3–6
Abstract

This paper describes a wideband dielectric resonator antenna with 30% fractional bandwidth, operating at 11 GHz. The structure consists of a hollow cylindrical dielectric pellet fed by individually switched excitation probes. The switched excitation pattern provides the antenna a radiation beam that can be moved through 360 degrees in the azimuth plane. Simulation and experimental results are presented to illustrate the advantages of this design.

Adaptive dielectric resonator antenna

TitleAdaptive dielectric resonator antenna
Publication TypeJournal Article
Year of Publication2007
AuthorsFayad, H., and P. Record
Journal2007 Loughborough Antennas and Propagation Conference, Proceedings
PaginationU174–U175
Abstract

A new class of hemispherical dielectric resonator antenna using mixed dielectric with beam agility is presented. The design of the antenna was optimized by extensive numerical simulations with the HFSS, Ansoft package. The antenna resonates at 5.6GHz, with a diameter of 26mm and Sit of -15dB. Varying the position of a regional dielectric discontinuity allows the principle radiation direction to be moved continuously through 360 degrees in the azimuth plane, with a vertical beam-width of 60 degrees. The size of this antenna makes it ideally suitable for hand held wireless communicators.

Ultra-Fine Pitch Stencil Printing for a Low Cost and Low Temperature Flip-Chip Assembly Process

TitleUltra-Fine Pitch Stencil Printing for a Low Cost and Low Temperature Flip-Chip Assembly Process
Publication TypeJournal Article
Year of Publication2007
AuthorsKay, R. W., S. Stoyanov, G. P. Glinski, C. Bailey, and M. P. Y. Desmulliez
JournalComponents and Packaging Technologies, IEEE Transactions on
Volume30
Pagination129 -136
Date Publishedmarch
ISSN1521-3331
Keywords100 C, 90 micron, assembling, computational fluid dynamics, computational fluid dynamics model, conductive adhesives, copper, copper column bumped die, Cu, electroformed stencil manufacturing, fine-pitch technology, flip-chip assembly process, flip-chip bonded electronic packages, flip-chip devices, integrated circuit bonding, integrated circuit interconnections, isotropic conductive adhesives, microengineering techniques, organic light emitting diode display chip, solder paste, solders, stencil fabrication, structural integrity, ultra-fine pitch stencil printing
Abstract

This paper presents the results of a packaging process based on the stencil printing of isotropic conductive adhesives (ICAs) that form the interconnections of flip-chip bonded electronic packages. Ultra-fine pitch (sub-100-mum), low temperature (100degC), and low cost flip-chip assembly is demonstrated. The article details recent advances in electroformed stencil manufacturing that use microengineering techniques to enable stencil fabrication at apertures sizes down to 20mum and pitches as small as 30mum. The current state of the art for stencil printing of ICAs and solder paste is limited between 150-mum and 200-mum pitch. The ICAs-based interconnects considered in this article have been stencil printed successfully down to 50-mum pitch with consistent printing demonstrated at 90-mum pitch size. The structural integrity or the stencil after framing and printing is also investigated through experimentation and computational modeling. The assembly of a flip-chip package based on copper column bumped die and ICA deposits stencil printed at sub-100-mum pitch is described. Computational fluid dynamics modeling of the print performance provides an indicator on the optimum print parameters. Finally, an organic light emitting diode display chip is packaged using this assembly process

DOI10.1109/TCAPT.2007.892085

Microengineered Two-Dimensional Arrays of Monomode Optical Fibers

TitleMicroengineered Two-Dimensional Arrays of Monomode Optical Fibers
Publication TypeJournal Article
Year of Publication2007
AuthorsWeiland, D., M. P. Y. Desmulliez, M. Luetzelschwab, A. Missoffe, and C. Beck
JournalMicroelectromechanical Systems, Journal of
Volume16
Pagination1506 -1514
Date Publisheddec.
ISSN1057-7157
Keywords2D bundles, clamping distance, closed loop systems, closed-loop feedback system, electrostatic actuation, electrostatic actuators, fiber pitch, laser feedback, metal-clad optical fibers, microengineered 2D arrays, monomode optical fibers, optical fibre cladding, optical fibre couplers, optical monitoring, single-mode optical fibers
Abstract

In this paper, a method to manufacture 2-D bundles of single-mode optical fibers of highly accurate pitch is presented. Electrostatic actuation of the metal-clad optical fibers is performed to align the fibers with submicrometer translational alignment accuracy. The manufacturing and alignment performance characteristics of the fiber holder are fully described. The sensitivity of the active-alignment procedure for a maximum displacement up to 90 mum is between 0.125 and 1.1 mum, depending on the clamping distance. An alignment accuracy of around 0.2 mum can be achieved with this alignment method. The combination of the electrostatic actuation with the optical monitoring of the fiber pitch in a closed-loop feedback system provides a highly accurate and sensitive alignment system.

DOI10.1109/JMEMS.2007.907777

A Cavity based High Gain MEMS Antenna for Microwave and Millimetre Wave Applications

TitleA Cavity based High Gain MEMS Antenna for Microwave and Millimetre Wave Applications
Publication TypeConference Paper
Year of Publication2007
AuthorsPavuluri, S. K., C. H. Wang, and A. J. Sangster
Conference NameAntennas and Propagation, 2007. EuCAP 2007. The Second European Conference on
Date Publishednov.
Keywordsantenna feeds, bandwidth, cavity based high gain microstrip patch antenna, efficiency 98 percent, MEMS antenna, micromechanical devices, microstrip antennas, microstrip feed line, microstrip lines, microwave antenna, microwave PCB substrate, millimetre wave antennas, millimetre wave applications, photolithography, photolithography technique, polymer ring structure, polymers, printed circuits, radiation measurements, reflection measurements, slot antennas, slot coupled antenna device, SU8 epoxy resin
Abstract

A cavity based high gain microstrip patch antenna with wide bandwidth is reported. The slot coupled antenna device was produced on a microwave PCB substrate with a suspended patch supported by a polymer ring structure. After the fabrication of the microstrip feed line and the coupling slot on the substrate and the patch on a polyimide film, two polymer rings of identical design were deposited on the microwave and the polyimide substrates respectively using a SU8 epoxy resin and the photolithography technique. The two polymer rings were then aligned and bonded together to obtain a cavity based patch antenna for high gain operation. The resultant height of the SU8 ring and hence the gap between the polymer and the microwave substrates was 1.5 mm. Reflection and radiation measurements were carried out to evaluate the performance of the antenna device. The results show that the device has a gain of 8.3 dBi at  12 GHz and a -10dB bandwidth of  2.5 GHz or 19%. The simulated results are demonstrated to be in good agreement with measurement. The predicted efficiency of the device is about 98%.

Direct and converse magnetoelectic effect in laminate bonded Terfenol-D-PZT composites

TitleDirect and converse magnetoelectic effect in laminate bonded Terfenol-D-PZT composites
Publication TypeJournal Article
Year of Publication2007
AuthorsRecord, P., C. Popov, J. Fletcher, E. Abraham, Z. Huang, H. Chang, and R. W. Whatmore
JournalSensors {&} Actuators: B. Chemical
Volume126
Pagination344–349
Abstract

Results from measurements of the direct and converse magnetoelectric (ME) effect on a three-layer, epoxy-bonded, laminate composite are presented. The laminae are a single transversely polarized piezoelectric elements (PZ29) sandwiched between two longitudinal-magnetic ally polarized magnetostrictive TD elements (Terfenol-D-TX GMM). The direct ME effect was determined by measuring laminate output with a Helmholtz-generated AC field (up to 7 Oe) in the range 50 Hz-100 kHz biased by a DC field (0-1000 Oe). Peak voltage output occurred at the sample's mechanical resonant frequency, its value depending on the strength and direction of the applied magnetic field. The peak output was 3061 mV at 3 Oe AC field and 1000 Oe bias, equivalent to 74.4 V cm(-1) Oe(-1). The peak output coefficient, however, was 93.6 V cm(-1) Oe(-1) at 0.1 Oe AC field and 1000 Oe DC bias. The reduction at higher drive amplitudes was attributed to increased Young's modulus of the TD phase. Anomalous peaks in the low frequency spectrum of sample's output are explained. The converse magnetoelectric effect was measured by recording the voltage induced in a solenoid encompassing the ME while exposed to a DC bias field and the PZ phase driven by a 10 VAC source. The peak output is shown to depend on the strength of the applied DC magnetic field and developed a maximum field of 15.4 Oe at the sample's mechanical resonant frequency. This equates to a converse magnetoelectric coefficient of 55 Oe cm kV(-1) (c) 2007 Elsevier B.V. All rights reserved.

Adaptive Dielectric Resonator Antenna

TitleAdaptive Dielectric Resonator Antenna
Publication TypeConference Paper
Year of Publication2007
AuthorsFayad, H., and P. Record
Conference NameAntennas and Propagation Conference, 2007. LAPC 2007. Loughborough
Abstract

A new class of hemispherical dielectric resonator antenna using mixed dielectric with beam agility is presented. The design of the antenna was optimized by extensive numerical simulations with the HFSS, Ansoft package. The antenna resonates at 5.6 GHz, with a diameter of 26 mm and Sn of -15 dB. Varying the position of a regional dielectric discontinuity allows the principle radiation direction to be moved continuously through 360 degrees in the azimuth plane, with a vertical beam-width of 60 degrees. The size of this antenna makes it ideally suitable for hand held wireless communicators.

Experimental investigation on new steerable dielectric resonator antenna

TitleExperimental investigation on new steerable dielectric resonator antenna
Publication TypeJournal Article
Year of Publication2007
AuthorsFayad, H., and P. Record
JournalElectronics Letters
Volume43
Pagination1009–1010
Abstract

A new steerable-dielectric resonator antenna is described. It consists of a movable annulus of heterogeneous dielectric sections surrounding a cylindrical core of another dielectric. The antenna far-field radiation was found to be manipulated by changing the angular position of this ring. This antenna demonstrates resonance at  1.2 GHz with a fractional bandwidth of 28.3% (Sn<sub>11</sub>{&}lt; - 10 dB), confirming an HFSS simulation of the same structure.

MEMS-based packaging of a UV-LED array

TitleMEMS-based packaging of a UV-LED array
Publication TypeJournal Article
Year of Publication2007
AuthorsLuetzelschwab, M., D. Weiland, E. Abraham, and M. P. Y. Desmulliez
JournalMicro Nano Letters, IET
Volume2
Pagination99 -102
Date Publisheddecember
ISSN1750-0443
Keywordselectrostatic actuation, light emitting diodes, magnetic actuation, mask-free lithography, MEMS-based packaging, microlens array, microlenses, micromechanical devices, modified UV-LIGA process, optical arrays, optoelectronic component, packaging, packaging solution, postfluorescence lifetime imaging, UV-LED array
Abstract

A packaging solution that accurately positions a microlens array over a UV-LED array for the purpose of either collimating or focusing the light emitted by the LEDs is presented. The assembled device can be used for mask-free lithography or for postfluorescence lifetime imaging of biological samples. The microdevice proposed permits the simultaneous dynamic monitoring of the microlens array in the vertical direction through electrostatic actuation and in the horizontal direction through magnetic actuation. Displacements of more than 70 mum can be achieved for the vertical actuation with less than 1% deviation over 17 h. The device, manufactured through a modified UV-LIGA process, can either be postprocessed on top of the UV-LED array or be temporarily connected to the optoelectronic component depending on whether continuous monitoring of the microlens array is required.

DOI10.1049/mnl:20070058

Wideband Dielectric Resonator Antenna with Reconfigurable Radiation Pattern

TitleWideband Dielectric Resonator Antenna with Reconfigurable Radiation Pattern
Publication TypeConference Paper
Year of Publication2007
AuthorsFayad, H., and P. Record
Conference NameAdaptive Hardware and Systems, 2007. AHS 2007. Second NASA/ESA Conference on
Abstract

This paper describes a wideband dielectric resonator antenna with 30% fractional bandwidth, operating at 11 GHz. The structure consists of a hollow cylindrical dielectric pellet fed by individually switched excitation probes. The switched excitation pattern provides the antenna a radiation beam that can be moved through 360 degrees in the azimuth plane. Simulation and experimental results are presented to illustrate the advantages of this design.

Corrections to ldquo;Ultra-Fine Pitch Stencil Printing for a Low Cost and Low Temperature Flip-Chip Assembly Process rdquo;

TitleCorrections to ldquo;Ultra-Fine Pitch Stencil Printing for a Low Cost and Low Temperature Flip-Chip Assembly Process rdquo;
Publication TypeJournal Article
Year of Publication2007
AuthorsKay, R. W., S. Stoyanov, G. P. Glinski, C. Bailey, and M. P. Y. Desmulliez
JournalComponents and Packaging Technologies, IEEE Transactions on
Volume30
Pagination359
Date Publishedjune
ISSN1521-3331
Abstract

Not available

DOI10.1109/TCAPT.2007.895649

Adaptive Dielectric Resonator Antenna

TitleAdaptive Dielectric Resonator Antenna
Publication TypeConference Paper
Year of Publication2007
AuthorsFayad, H., and P. Record
Conference NameAntennas and Propagation Conference, 2007. LAPC 2007. Loughborough
Abstract

A new class of hemispherical dielectric resonator antenna using mixed dielectric with beam agility is presented. The design of the antenna was optimized by extensive numerical simulations with the HFSS, Ansoft package. The antenna resonates at 5.6 GHz, with a diameter of 26 mm and Sn of -15 dB. Varying the position of a regional dielectric discontinuity allows the principle radiation direction to be moved continuously through 360 degrees in the azimuth plane, with a vertical beam-width of 60 degrees. The size of this antenna makes it ideally suitable for hand held wireless communicators.

Microengineered dynamometer for microfan thrust measurement

TitleMicroengineered dynamometer for microfan thrust measurement
Publication TypeJournal Article
Year of Publication2006
AuthorsDhariwal, R., M. Leonard, M. P. Y. Desmulliez, B. Reuben, and J. Armstrong
JournalElectronics Letters
Volume42
Pagination1394 -1395
Date Published23
ISSN0013-5194
Keywordsaxial-flow microfans, beams (structures), cup-shaped bearings, drag, dynamometers, fans, friction, microengineered dynamometer, microengineered three-beam suspended structure, microfan thrust measurement, micromechanical devices, microturbines, Ni, nickel, thrust force, thrust testing, torsional friction drag, turbines
Abstract

The fabrication, development and thrust testing of a microengineered three-beam suspended structure manufactured in nickel is described. The structure is intended to be used as a support for axial-flow microfans and microturbines. The purpose of the test device is to measure torsional friction drag as a function of thrust force in configurations where microfans have cup-shaped bearings

DOI10.1049/el:20062596

Two-dimensional monomode fibre array manufacture using UV-LIGA process

TitleTwo-dimensional monomode fibre array manufacture using UV-LIGA process
Publication TypeJournal Article
Year of Publication2005
AuthorsWeiland, D., M. Lutzelschwab, and M. P. Y. Desmulliez
JournalElectronics Letters
Volume41
Pagination978 - 979
Date Publishedaug.
ISSN0013-5194
Keywords2D monomode fibre array manufacture, closed loop feedback alignment system, electrostatic movement, fibre position, LIGA, optical arrays, optical fabrication, optical fibres, optical monitoring, singlemode optical fibres, submicron translational alignment accuracy, ultraviolet lithography, UV-LIGA process
Abstract

A method to manufacture two-dimensional bundles of singlemode optical fibres is described. Submicron translational alignment accuracy is demonstrated by combining electrostatic movement and optical monitoring of the actual fibre position in a closed loop feedback alignment system.

DOI10.1049/el:20051894

Submicron alignment of a two-dimensional array of multiple single-mode fibers

TitleSubmicron alignment of a two-dimensional array of multiple single-mode fibers
Publication TypeJournal Article
Year of Publication2005
AuthorsLuetzelschwab, M., D. Weiland, and M. P. Y. Desmulliez
JournalPhotonics Technology Letters, IEEE
Volume17
Pagination2634 - 2636
Date Publisheddec.
ISSN1041-1135
Keywords125 mum, adhesive filled holes, closed-loop feedback system, copper-coated optical fibers, electrostatic actuation, electrostatic actuators, electrostatic forces, fiber position, micro-optics, microassembling, microassembly, microholder alignment performance, multimode optical fibers, multiple single-mode fibers, optical arrays, optical fiber alignment, optical fibre cladding, optical fibre fabrication, optical fibre testing, optical monitoring, optoelectronic emitter array, submicron alignment, two-dimensional fiber array
Abstract

This letter presents a patented method to align single- or multimode optical fibers on top of an optoelectronic emitter array. Electrostatic forces are used to align copper-coated optical fibers within adhesive filled holes. The manufacturing and alignment performance of a microholder with a hole diameter of 1000 mu;m are fully characterized. The outer diameter of the optical single-mode fiber is 125 mu;m including the cladding. A submicron alignment accuracy can be inferred from the measurements taken. The sensitivity of the alignment procedure has been found to be between 0.25 and 1 mu;m per volt depending on the clamping distance. The combination of the electrostatic movement and the optical monitoring of the fiber position in a closed-loop feedback system yield a highly accurate and sensitive active alignment system.

DOI10.1109/LPT.2005.859531

Manufacture and characterisation of micro-engineered DC-DC power converter using UV-LIGA process

TitleManufacture and characterisation of micro-engineered DC-DC power converter using UV-LIGA process
Publication TypeJournal Article
Year of Publication2005
AuthorsFlynn, D., A. Toon, and M. P. Y. Desmulliez
JournalElectronics Letters
Volume41
Pagination1351 - 1353
Date Publishednov.
ISSN0013-5194
Keywords1 to 5000 kHz, DC-DC power converters, DC-DC power convertors, eddy current loss, electrodeposition, electron device manufacture, flip-chip bonding assembly, flip-chip devices, hysteresis loss, iron alloys, LIGA, magnetic cores, micro-inductors, microassembling, micromachining, micromechanical devices, nickel alloys, nickel-iron cores, NiFe, photoresists, thin film inductors, thin film laminates, ultraviolet lithography, UV-LIGA process, windings
Abstract

A novel method to manufacture a micro-inductor that is based on flip-chip bonding assembly is described. The micro-inductor is developed for DC-DC converters operating in the MHz switching frequency. The fabricated inductors have an inductance ranging from 0.12 to 118 mu;H. An optimum Q-factor of 2 was attained at 1 MHz. Nickel-iron cores with integrated air-gaps maintained a constant inductance across a 1 kHz-5 MHz bandwidth. The thin film laminate minimised eddy current loss and hysteresis loss was negligible. Impedance increased linearly with frequency, indicating that parasitic capacitance effects in this frequency range were negligible. The micro-inductor operated at an efficiency of 92% at 1 MHz, achieving a power density of 4.2 W/cm3.

DOI10.1049/el:20053257

Operation of an optoelectronic crossbar switch containing a terabit-per-second free-space optical interconnect

TitleOperation of an optoelectronic crossbar switch containing a terabit-per-second free-space optical interconnect
Publication TypeJournal Article
Year of Publication2005
AuthorsWalker, A. C., S. J. Fancey, M. P. Y. Desmulliez, M. G. Forbes, J. J. Casswell, G. S. Buller, M. R. Taghizadeh, J. A. B. Dines, C. R. Stanley, G. Pennelli, A. R. Boyd, J. L. Pearson, P. Horan, D. Byrne, J. Hegarty, S. Eitel, H. - P. Gauggel, K. - H. Gulden, A. Gauthier, P. Benabes, J. - L. Gutzwiller, M. Goetz, and J. Oksman
JournalQuantum Electronics, IEEE Journal of
Volume41
Pagination1024 - 1036
Date Publishedjuly
ISSN0018-9197
Keywords0.2 Tbit/s, 14.6 mm, 15.6 mm, 250 Mbit/s, 50 Mbit/s, aggregate data input, CMOS chip, CMOS integrated circuits, elemental semiconductors, flip-chip devices, flip-chipped InGaAs-GaAs optical interface chip, gallium arsenide, III-V semiconductors, indium compounds, InGaAs-GaAs, internal optical fan-out, optical interconnect, optical interconnections, optical switches, optoelectronic crossbar switch, Si, silicon, silicon very-large-scale-integrated circuit, single-channel routing, VLSI
Abstract

The experimental operation of a terabit-per-second scale optoelectronic connection to a silicon very-large-scale-integrated circuit is described. A demonstrator system, in the form of an optoelectronic crossbar switch, has been constructed as a technology test bed. The assembly and testing of the components making up the system, including a flip-chipped InGaAs-GaAs optical interface chip, are reported. Using optical inputs to the electronic switching chip, single-channel routing of data through the system at the design rate of 250 Mb/s (without internal fan-out) was achieved. With 4000 optical inputs, this corresponds to a potential aggregate data input of a terabit per second into the single 14.6 times; 15.6 mm CMOS chip. In addition 50-Mb/s data rates were switched utilizing the full internal optical fan-out included in the system to complete the required connectivity. This simultaneous input of data across the chip corresponds to an aggregate data input of 0.2 Tb/s. The experimental system also utilized optical distribution of clock signals across the CMOS chip.

DOI10.1109/JQE.2005.848909

Electric field breakdown at micrometre separations in air and nitrogen at atmospheric pressure

TitleElectric field breakdown at micrometre separations in air and nitrogen at atmospheric pressure
Publication TypeJournal Article
Year of Publication2000
AuthorsDhariwal, R. S., J. - M. Torres, and M. P. Y. Desmulliez
JournalScience, Measurement and Technology, IEE Proceedings -
Volume147
Pagination261 -265
Date Publishedsep
ISSN1350-2344
Keywords0.5 to 15 mu, 0.5 to 15 mum, 4 mum, air, atmospheric pressure, breakdown voltage, electric breakdown, electric field breakdown, electrode spacings, energy dispersive analysis, m, micrometre separations, microprotrusions, N2, nitrogen, Paschen law, quantum tunnelling, tunnelling, up to 4 mu, voltage measurement, work function
Abstract

For efficient operation, micromotors and microactuators, such as those employed in microsystems, are required to operate with high electric fields at electrode separations of the order of micrometres. An apparatus was built to accurately measure the breakdown voltage for electrode spacings as low as 0.5 mu;m. Breakdown voltage measurements in air and nitrogen are presented and discussed for the gap range 0.5 to 15 mu;m. Energy dispersive analysis of X-rays (EDAX) confirms the transfer of material from cathode to anode and vice versa during the breakdown mechanism. The Paschen law has been confirmed not to be applicable at gap settings of less than 4 mu;m. The shape of the curve and the breakdown voltage values are found to be the same for different gases and different high pressures up to 4 mu;m separation. Below this value, an analytical explanation of the breakdown voltage based on quantum tunnelling of electrons is obtained in terms of electrical field enhancement at microprotrusions and the work function of the electrode material

DOI10.1040/ip-smt:20000506

Analysis and design of vertical cavity binary-phase modulators

TitleAnalysis and design of vertical cavity binary-phase modulators
Publication TypeJournal Article
Year of Publication2000
AuthorsClarici, G., M. P. Y. Desmulliez, and B. S. Wherrett
JournalOptoelectronics, IEE Proceedings -
Volume147
Pagination377 -381
Date Publisheddec
ISSN1350-2433
Keywordsamplitude reflectivity, asymmetric Fabry-Perot cavity reflection mode modulators, bilinear transformation, binary-phase modulator, cavity resonance, conformal mapping, Fabry-Perot equation, Fabry-Perot resonators, on-resonance operation, operational parameters, optical design techniques, optical modulation, optical parameters, semiconductor device models, semiconductor quantum wells, vertical cavity binary-phase modulator design
Abstract

The Fabry-Perot equation used to model asymmetric Fabry-Perot cavity reflection mode modulators can be considered as a bilinear transformation between the amplitude reflectivity of the modulator and the optical parameters of the cavity. Conformal mapping of this transformation into a suitable plane is used to visualise the operation of such a device working as a binary-phase modulator and to evaluate the tolerance of points of operation towards changes in the physical or operational parameters. Operation away from cavity resonance is shown to be less sensitive to parameter variations than conventional on-resonance operation

DOI10.1049/ip-opt:20000805

Design and construction of an optoelectronic crossbar switch containing a terabit per second free-space optical interconnect

TitleDesign and construction of an optoelectronic crossbar switch containing a terabit per second free-space optical interconnect
Publication TypeJournal Article
Year of Publication1999
AuthorsWalker, A. C., M. P. Y. Desmulliez, M. G. Forbes, S. J. Fancey, G. S. Buller, M. R. Taghizadeh, J. A. B. Dines, C. R. Stanley, G. Pennelli, A. R. Boyd, P. Horan, D. Byrne, J. Hegarty, S. Eitel, H. - P. Gauggel, K. - H. Gulden, A. Gauthier, P. Benabes, J. - L. Gutzwiller, and M. Goetz
JournalSelected Topics in Quantum Electronics, IEEE Journal of
Volume5
Pagination236 -249
Date Publishedmar/apr
ISSN1077-260X
Keywords1 Tbit/s, electro optical modulators, electro-optical modulation, electro-optical switches, flip-chip bonded, flip-chip devices, free-space optics, gallium arsenide, hybrid very large scale integrated optoelectronics technology, III-V semiconductors, indium compounds, InGaAs, InGaAs-based detectors, integrated optoelectronics, optical design techniques, optical fabrication, optical interconnections, optoelectronic crossbar switch design, optoelectronic crossbar switch fabrication, photodetectors, silicon integrated circuits, single chip, smart pixels, Tb/s aggregate data input/output, terabit per second free-space optical interconnect
Abstract

The completed detailed design and initial phases of construction of an optoelectronic crossbar demonstrator are presented. The experimental system uses hybrid very large scale integrated optoelectronics technology whereby InGaAs-based detectors and modulators are flip-chip bonded onto silicon integrated circuits. The system aims to demonstrate a 1-Tb/s aggregate data input/output to a single chip by means of free-space optics

DOI10.1109/2944.778297