Yr Athro David Wallis
(Translated he/him)
Athro - Lled-ddargludyddion Cyfansawdd
Cyfarwyddwr Rhyngwyneb Academaidd, Sefydliad Lled-ddargludyddion Cyfansawdd
- Ar gael fel goruchwyliwr ôl-raddedig
Trosolwyg
Gallium Nitride yn lled-ddargludyddion newydd sy'n cyflwyno chwyldro ym mherfformiad ac effeithlonrwydd LEDs a transistorau. Mae fy ymchwil yn canolbwyntio ar ddatblygu twf epitacsiol a thechnolegau dyfeisiau yn y deunydd hwn. Yn benodol, rwy'n datblygu GaN ar Si a fydd yn darparu'r genhedlaeth nesaf o ddyfeisiau electronig GaN cost isel a Gan ciwbig-GaN, a fydd yn gwella effeithlonrwydd ac ansawdd goleuadau LED yn sylweddol. Yn ddiweddar, rwyf hefyd wedi lansio cwmni deillio o Kubos, a fydd yn datblygu'n fasnachol dechnoleg twf ciwbig GaN yn seiliedig ar fy ymchwil.
Cyhoeddiad
2024
- Gundimeda, A. et al. 2024. Impact of stacking faults on the luminescence of a zincblende InGaN/GaN single quantum well. Journal of Physics D: Applied Physics 58(2), article number: 25112. (10.1088/1361-6463/ad8662)
- Dyer, D. et al. 2024. Efficiency droop in zincblende InGaN/GaN quantum wells. Nanoscale 16(29), pp. 13953-13961. (10.1039/D4NR00812J)
- Gundimeda, A., Kusch, G., Frentrup, M., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2024. Cathodoluminescence studies of the optical properties of a zincblende InGaN/GaN single quantum well. Nanotechnology 35(39), article number: 395705. (10.1088/1361-6528/ad5db4)
- Chen, C. et al. 2024. Threshold voltage mapping at the nanoscale of GaN-based high electron mobility transistor structures using hyperspectral scanning capacitance microscopy. Applied Physics Letters 124(23), article number: 232107. (10.1063/5.0203646)
2023
- Chen, C., Ghosh, S., Adams, F., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2023. Scanning capacitance microscopy of GaN-based high electron mobility transistor structures: A practical guide. Ultramicroscopy 254, article number: 113833. (10.1016/j.ultramic.2023.113833)
- Hinz, A. M., Ghosh, S., Fairclough, S. M., Griffiths, J. T., Kappers, M. J., Oliver, R. A. and Wallis, D. J. 2023. Strategy for reliable growth of thin GaN Caps on AlGaN HEMT structures. Journal of Crystal Growth 624, article number: 127420. (10.1016/j.jcrysgro.2023.127420)
- Leigh, W. et al. 2023. Monitoring of the initial stages of diamond growth on aluminum nitride using in situ spectroscopic ellipsometry. ACS Omega 8(33), pp. 30442-30449. (10.1021/acsomega.3c03609)
- Yang, H. et al. 2023. A cross-linkable, organic down-converting material for white light emission from hybrid LEDs. Journal of Materials Chemistry C Materials for optical and electronic devices 11(29), pp. 9984-9995. (10.1039/D2TC05139G)
- Wadsworth, A., Thrimawithana, D. J., Zhao, L., Neuburger, M., Oliver, R. A. and Wallis, D. J. 2023. GaN-based cryogenic temperature power electronics for superconducting motors in cryo-electric aircraft. Superconductor Science and Technology 36(9), article number: 94002. (10.1088/1361-6668/ace5e7)
- Wade, T., Gundimeda, A., Kappers, M., Frentrup, M., Fairclough, S., Wallis, D. and Oliver, R. 2023. MOVPE studies of zincblende GaN on 3C-SiC/Si(0 0 1). Journal of Crystal Growth 611, article number: 127182. (10.1016/j.jcrysgro.2023.127182)
- Ghosh, S., Hinz, A. M., Frentrup, M., Alam, S., Wallis, D. J. and Oliver, R. 2023. Design of step-graded AlGaN buffers for GaN-on-Si heterostructures grown by MOCVD. Semiconductor Science and Technology 38(4), article number: 44001. (10.1088/1361-6641/acb9b6)
- Xiu, H., Fairclough, S. M., Gundimeda, A., Kappers, M. J., Wallis, D. J., Oliver, R. A. and Frentrup, M. 2023. Polarity determination of crystal defects in zincblende GaN by aberration-corrected electron microscopy. Journal of Applied Physics 133, article number: 105302. (10.1063/5.0138478)
2022
- Binks, D. J., Dawson, P., Oliver, R. A. and Wallis, D. J. 2022. Cubic GaN and InGaN/GaN quantum wells. Applied Physics Reviews 9, article number: 41309. (10.1063/5.0097558)
- Yin, Y., Pinchbeck, J., O'Regan, C., Guiney, I., Wallis, D. J. and Lee, K. B. 2022. Fabrication of semi-polar (11-22) GaN V-groove MOSFET using wet etching trench opening technique. IEEE Electron Device Letters 43(10), pp. 1641-1644. (10.1109/LED.2022.3203633)
- Gundimeda, A., Rostami, M., Frentrup, M., Hinz, A., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2022. Influence of AlxGa1-xN nucleation layers on MOVPE-grown zincblende GaN epilayers on 3C-SiC/Si(001). Journal of Physics D: Applied Physics 55(7), article number: 175110. (10.1088/1361-6463/ac4c58)
- Gundimeda, A., Frentrup, M., Fairclough, S. M., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2022. Investigation of wurtzite formation in MOVPE-grown zincblende GaN epilayers on AlxGa1−xN nucleation layers. Journal of Applied Physics 131(11), article number: 115703. (10.1063/5.0077186)
2021
- Dyer, D. et al. 2021. The effect of thermal annealing on the optical properties of Mg-doped zincblende GaN epilayers. Journal of Applied Physics 130(8), article number: 85705. (10.1063/5.0057824)
- Spiridon, B. F. et al. 2021. Method for inferring the mechanical strain of GaN-on-Si epitaxial layers using optical profilometry and finite element analysis. Optical Materials Express 11(6), pp. 1643-1655. (10.1364/OME.418728)
- Church, S. A. et al. 2021. Photoluminescence efficiency of zincblende InGaN/GaN quantum wells. Journal of Applied Physics 129, article number: 175702. (10.1063/5.0046649)
- Vacek, P. et al. 2021. Defect structures in (001) zincblende GaN/3C-SiC nucleation layers. Journal of Applied Physics 129(15), article number: 155306. (10.1063/5.0036366)
- Cuenca, J. A. et al. 2021. Thermal stress modelling of diamond on GaN/III-Nitride membranes. Carbon 174, pp. 647-661. (10.1016/j.carbon.2020.11.067)
2020
- Sun, C. et al. 2020. Thin film gallium nitride (GaN) based acoustofluidic tweezer: modelling and microparticle manipulation. Ultrasonics 108, article number: 106202. (10.1016/j.ultras.2020.106202)
- Ding, B. et al. 2020. Alloy segregation at stacking faults in zincblende GaN heterostructures. Journal of Applied Physics 128(14), article number: 145703. (10.1063/5.0015157)
- Sun, C. et al. 2020. Gallium nitride: a versatile compound semiconductor as novel piezoelectric film for acoustic tweezer in manipulation of cancer cells. IEEE Transactions on Electron Devices 67(8), pp. 3355-3361. (10.1109/TED.2020.3002498)
- Church, S. A. et al. 2020. Stacking fault-associated polarised surface-emitted photoluminescence from zincblende InGaN/GaN quantum wells. Applied Physics Letters 117(3), article number: 32103. (10.1063/5.0012131)
- Wiles, A. A. et al. 2020. A poly(urethane)-encapsulated benzo[2,3-d:6,7-d’]diimidazole organic down-converter for green hybrid LEDs. Materials Chemistry Frontiers 4(3), pp. 1006-1012. (10.1039/C9QM00771G)
2019
- Mandal, S. et al. 2019. Thick, adherent diamond films on AlN with low thermal barrier resistance. ACS Applied Materials and Interfaces 11(43), pp. 40826-40834. (10.1021/acsami.9b13869)
- Lee, L. Y., Frentrup, M., Vacek, P., Massabuau, F. C., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2019. Investigation of MOVPE-grown zincblende GaN nucleation layers on 3C-SiC/Si substrates. Journal of Crystal Growth 524, article number: 125167. (10.1016/j.jcrysgro.2019.125167)
- Lee, L. Y., Frentrup, M., Vacek, P., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2019. Investigation of stacking faults in MOVPE-grown zincblende GaN by XRD and TEM. Journal of Applied Physics 125, article number: 105303. (10.1063/1.5082846)
- Angioni, E. et al. 2019. Implementing fluorescent MOFs as down-converting layers in hybrid light-emitting diodes. Journal of Materials Chemistry. C 7(8), pp. 2394-2400. (10.1039/C9TC00067D)
2018
- Yi, L., Frentrup, M., Kappers, M., Oliver, R., Humphreys, C. and Wallis, D. 2018. Effect of growth temperature and V/III-ratio on the surface morphology of MOVPE-grown cubic zincblende GaN. Journal of Applied Physics 124, article number: 105302.
- Choi, F. S. et al. 2018. Vertical leakage mechanism in GaN on Si high electron mobility transistor buffer layers. Journal of Applied Physics 124(5), article number: 55702. (10.1063/1.5027680)
- Roff, C. et al. 2018. Utilization of waveform measurements for degradation analysis of AlGaN/GaN HFETs. Presented at: ARFTG 70th Microwave Measurement Symposium, Tempe, AZ, USA, 27-30 November 20072007 70th ARFTG Microwave Measurement Conference (ARFTG). IEEE, (10.1109/ARFTG.2007.8376173)
- Zaidi, Z. H. et al. 2018. Effects of surface plasma treatment on threshold voltage hysteresis and instability in metal-insulator-semiconductor (MIS) AlGaN/GaN heterostructure HEMTs. Journal of Applied Physics 123(18), article number: 184503. (10.1063/1.5027822)
- Church, S. A. et al. 2018. Effect of stacking faults on the photoluminescence spectrum of zincblende GaN. Journal of Applied Physics 123(18), article number: 185705. (10.1063/1.5026267)
- Tang, F. et al. 2018. Nanoscale structural and chemical analysis of F-implanted enhancement-mode InAlN/GaN heterostructure field effect transistors. Journal of Applied Physics 123(2), article number: 24902. (10.1063/1.5006255)
2017
- Jiang, S. et al. 2017. All-GaN-integrated cascode heterojunction field effect transistors. IEEE Transactions on Power Electronics 32(11), pp. 8743-8750. (10.1109/TPEL.2016.2643499)
- Mandal, S. et al. 2017. Surface zeta potential and diamond seeding on gallium nitride films. ACS Omega 2(10), pp. 7275-7280. (10.1021/acsomega.7b01069)
- Eblabla, A., Benakaprasad, B., Li, X., Wallis, D., Guiney, I., Humphreys, C. and Elgaid, K. 2017. Passive components technology for THz-Monolithic Integrated Circuits (THz-MIC). Presented at: 18th International Radar Symposium (IRS), 2017, Prague, Czech Republic, 28-30 June 2017Radar Symposium Conference Proceedings. pp. 1-7., (10.23919/IRS.2017.8008166)
- Rae, K. et al. 2017. InGaN µLEDs integrated onto colloidal quantum dot functionalized ultra-thin glass. Optics Express 25(16), pp. 19179-19184. (10.1364/OE.25.019179)
- Benakaprasad, B., Eblabla, A., Li, X., Wallis, D., Guiney, I. and Elgaid, K. 2017. Design and performance comparison of various terahertz microstrip antennas on GaN-on-low resistivity silicon substrates for TMIC. Presented at: Microwave Conference (APMC), Asia-Pacific, New Delhi, India, 5-9 Dec 2016Proceedings of the Asia-Pacific Microwave Conference 2016. IEEE, (10.1109/APMC.2016.7931368)
- Eblabla, A. M., Li, X., Wallis, D. J., Guiney, I. and Elgaid, K. 2017. GaN on low-resistivity silicon THz high-Q passive device technology. IEEE Transactions on Terahertz Science & Technology 7(1), pp. 93-97. (10.1109/TTHZ.2016.2618751)
2016
- Benakaprasad, B. et al. 2016. Terahertz monolithic integrated circuits (TMICs) array antenna technology on GaN-on-Low resistivity silicon substrates. Presented at: 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz),, Copenhagen, Denmark, 25-30 Sep 20162016 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz),. IEEE, (10.1109/IRMMW-THz.2016.7758488)
- Jamil, S., Gammon, T., Wallis, D. and Fontaine, M. D. 2016. Standby person for electrical tasks and rescue guidelines for electrical incident victims. Presented at: Petroleum and Chemical Industry Technical Conference (PCIC), Philadelphia, PA, USA, 19-22 Sep 2016. IEEE, (10.1109/PCICON.2016.7589220)
- Chatterjee, I. et al. 2016. Impact of buffer charge on the reliability of carbon doped AlGaN/GaN-on-Si HEMTs. Presented at: 2016 IEEE International Reliability Physics Symposium (IRPS), Pasadena, CA, USA, 17-21 April 20162016 IEEE International Reliability Physics Symposium (IRPS). IEEE pp. 4A41-4A45., (10.1109/IRPS.2016.7574529)
- Wallis, D. 2016. The hazards of risk assessment. Presented at: Electrical Safety Workshop (ESW), Jacksonville, FL, USA, 6-11 March 2016. , (10.1109/ESW.2016.7499706)
- Waller, W. M. et al. 2016. Subthreshold Mobility in AlGaN/GaN HEMTs. IEEE Transactions on Electron Devices 63(5), pp. 1861-1865. (10.1109/TED.2016.2542588)
- Miaja, P. F. et al. 2016. Modelling the closely-coupled cascode switching process. Presented at: 2016 IEEE Energy Conversion Congress and Exposition (ECCE), Milwaukee, WI, 18-22 September 20162016 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, (10.1109/ECCE.2016.7855268)
- Benakaprasad, B. et al. 2016. Terahertz microstrip single patch antenna technology on GaN-on-Low resistivity silicon substrates for TMIC. Presented at: IET Colloquium on Antennas, Wireless and Electromagnetics, Glasgow, UK, 26 May 2016.
- Eblabla, A., Li, X., Wallis, D., Benakaprasad, B., Guiney, I. and Elgaid, K. 2016. High frequency active and passives devices using GaN on low resistivity silicon. Presented at: ARMMS RF & Microwave Society Conference, Milton Common Nr Thame, UK, 18-19 Apr 2016.
- Elgaid, K. et al. 2016. MMIC-compatible microstrip technology for GaN-HEMTs on low resistivity silicon substrate. Presented at: International Workshop on Nitride Semiconductors (IWN 2016), Orlando, FL, USA, 2-7 Oct 2016.
2015
- Eblabla, A., Li, X., Thayne, I., Wallis, D. J., Guiney, I. and Elgaid, K. 2015. High performance GaN high electron mobility transistors on low resistivity silicon for X -Band Applications. IEEE Electron Device Letters 36(9), pp. 899-901. (10.1109/LED.2015.2460120)
- Waller, W. M. et al. 2015. Interface state artefact in long gate-length AlGaN/GaN HEMTs. IEEE Transactions of Electron Devices 62(8), pp. 2464-2469. (10.1109/TED.2015.2444911)
- Eblabla, A., Wallis, D., Guiney, I. and Elgaid, K. 2015. Novel shielded coplanar waveguides on GaN-on-Low resistivity Si substrates for MMIC applications. IEEE Microwave and Wireless Components Letters 25(7), pp. 427-429. (10.1109/LMWC.2015.2429120)
2010
- Ashley, T. et al. 2010. High-performance InSb based quantum well field effect transistors for low-power dissipation applications. Presented at: 2009 IEEE International Electron Devices Meeting (IEDM), Baltimore, MD, USA, 7-9 December 20092009 IEEE International Electron Devices Meeting (IEDM). IEEE pp. 1., (10.1109/IEDM.2009.5424207)
2009
- Janssen, J. et al. 2009. X-Band GaN SPDT MMIC with over 25 watt linear power handling. Presented at: European Microwave Integrated Circuit Conference, 2008, Amsterdam, The Netherlands, 27-28 October 20092008 European Microwave Integrated Circuit Conference. IEEE, (10.1109/EMICC.2008.4772261)
- Riedel, G. J. et al. 2009. Reducing thermal resistance of AlGaN/GaN electronic devices using novel nucleation layers. IEEE Electron Device Letters 30(2), pp. 103-106. (10.1109/LED.2008.2010340)
2008
- Riedel, G. et al. 2008. Nanosecond timescale thermal dynamics of AlGaN/GaN electronic devices. IEEE Electron Device Letters 29(5), pp. 416-418. (10.1109/LED.2008.919779)
- Radosavljevic, M. et al. 2008. High-performance 40nm gate length InSb p-channel compressively strained quantum well field effect transistors for low-power (VCC=0.5V) logic applications. Presented at: IEEE International Electron Devices Meeting, San Francisco, CA, 15-17 Dec 2008. , (10.1109/IEDM.2008.4796798)
2007
- Sarua, A., Ji, H., Hilton, K. P., Wallis, D., Uren, M. J., Martin, T. and Kuball, M. 2007. Thermal boundary resistance between GaN and substrate in AlGaN/GaN electronic devices. IEEE Transactions of Electron Devices 54(12), pp. 3152-3158. (10.1109/TED.2007.908874)
- Ashley, T. et al. 2007. Indium antimonide based quantum well FETs for ultra-high speed electronics. Presented at: 64th Device Research Conference, State College, PA, 26-28 June 2006. pp. 201., (10.1109/DRC.2006.305056)
- Kuball, M. et al. 2007. Time-resolved temperature measurement of AlGaN/GaN electronic devices using micro-raman spectroscopy. IEEE Electron Device Letters 28(2), pp. 86-89. (10.1109/LED.2006.889215)
- Ashley, T. et al. 2007. Heterogeneous InSb quantum well transistors on silicon for ultra-high speed, low power logic applications. Electronics letters 43(14), article number: 777. (10.1049/el:20071335)
2006
- Wallis, D. 2006. Class F at class B temperatures is it time for a change?. Presented at: Conference Record of the 2006 IEEE International Symposium on Electrical Insulation, 2006, Toronto, Ont., Canada, 11-14 June 2006. , (10.1109/ELINSL.2006.1665243)
- Ashley, T. et al. 2006. Indium antimonide based technology for RF applications. Presented at: Compound Semiconductor Integrated Circuit Symposium, San Antonio, TX, 12-15 Nov 2006. , (10.1109/CSICS.2006.319918)
- Uren, M. et al. 2006. Control of Short-Channel Effects in GaN/AlGaN HFETs. Presented at: 1st European Microwave Integrated Circuits Conference, Manchester, UK, 10-13 Sept 20062006 European Microwave Integrated Circuits Conference. IEEE pp. 65-65., (10.1109/EMICC.2006.282751)
2005
- Datta, S. et al. 2005. 85nm gate length enhancement and depletion mode InSb quantum well transistors for ultra high speed and very low power digital logic applications. Presented at: IEEE International Electron Devices Meeting, Washington DC, 5 Dec 2005Electron Devices Meeting, 2005. IEDM Technical Digest. IEEE International. IEEE, (10.1109/IEDM.2005.1609466)
2001
- Wallis, D., Keir, A., Emeny, M. and Martin, T. 2001. Measurement of III-V quaternary composition using X-ray diffraction. IEE Proceedings Optoelectronics 148(2), pp. 97-100. (10.1049/ip-opt:20010442)
1996
- Wallis, D., Watson, A. and Mo, N. 1996. Cardiac neurones of automatic ganglia. Microscopy Research and Technique 35(1), pp. 69-79. (10.1002/(SICI)1097-0029(19960901)35:1<69::AID-JEMT6>3.0.CO;2-N)
Articles
- Gundimeda, A. et al. 2024. Impact of stacking faults on the luminescence of a zincblende InGaN/GaN single quantum well. Journal of Physics D: Applied Physics 58(2), article number: 25112. (10.1088/1361-6463/ad8662)
- Dyer, D. et al. 2024. Efficiency droop in zincblende InGaN/GaN quantum wells. Nanoscale 16(29), pp. 13953-13961. (10.1039/D4NR00812J)
- Gundimeda, A., Kusch, G., Frentrup, M., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2024. Cathodoluminescence studies of the optical properties of a zincblende InGaN/GaN single quantum well. Nanotechnology 35(39), article number: 395705. (10.1088/1361-6528/ad5db4)
- Chen, C. et al. 2024. Threshold voltage mapping at the nanoscale of GaN-based high electron mobility transistor structures using hyperspectral scanning capacitance microscopy. Applied Physics Letters 124(23), article number: 232107. (10.1063/5.0203646)
- Chen, C., Ghosh, S., Adams, F., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2023. Scanning capacitance microscopy of GaN-based high electron mobility transistor structures: A practical guide. Ultramicroscopy 254, article number: 113833. (10.1016/j.ultramic.2023.113833)
- Hinz, A. M., Ghosh, S., Fairclough, S. M., Griffiths, J. T., Kappers, M. J., Oliver, R. A. and Wallis, D. J. 2023. Strategy for reliable growth of thin GaN Caps on AlGaN HEMT structures. Journal of Crystal Growth 624, article number: 127420. (10.1016/j.jcrysgro.2023.127420)
- Leigh, W. et al. 2023. Monitoring of the initial stages of diamond growth on aluminum nitride using in situ spectroscopic ellipsometry. ACS Omega 8(33), pp. 30442-30449. (10.1021/acsomega.3c03609)
- Yang, H. et al. 2023. A cross-linkable, organic down-converting material for white light emission from hybrid LEDs. Journal of Materials Chemistry C Materials for optical and electronic devices 11(29), pp. 9984-9995. (10.1039/D2TC05139G)
- Wadsworth, A., Thrimawithana, D. J., Zhao, L., Neuburger, M., Oliver, R. A. and Wallis, D. J. 2023. GaN-based cryogenic temperature power electronics for superconducting motors in cryo-electric aircraft. Superconductor Science and Technology 36(9), article number: 94002. (10.1088/1361-6668/ace5e7)
- Wade, T., Gundimeda, A., Kappers, M., Frentrup, M., Fairclough, S., Wallis, D. and Oliver, R. 2023. MOVPE studies of zincblende GaN on 3C-SiC/Si(0 0 1). Journal of Crystal Growth 611, article number: 127182. (10.1016/j.jcrysgro.2023.127182)
- Ghosh, S., Hinz, A. M., Frentrup, M., Alam, S., Wallis, D. J. and Oliver, R. 2023. Design of step-graded AlGaN buffers for GaN-on-Si heterostructures grown by MOCVD. Semiconductor Science and Technology 38(4), article number: 44001. (10.1088/1361-6641/acb9b6)
- Xiu, H., Fairclough, S. M., Gundimeda, A., Kappers, M. J., Wallis, D. J., Oliver, R. A. and Frentrup, M. 2023. Polarity determination of crystal defects in zincblende GaN by aberration-corrected electron microscopy. Journal of Applied Physics 133, article number: 105302. (10.1063/5.0138478)
- Binks, D. J., Dawson, P., Oliver, R. A. and Wallis, D. J. 2022. Cubic GaN and InGaN/GaN quantum wells. Applied Physics Reviews 9, article number: 41309. (10.1063/5.0097558)
- Yin, Y., Pinchbeck, J., O'Regan, C., Guiney, I., Wallis, D. J. and Lee, K. B. 2022. Fabrication of semi-polar (11-22) GaN V-groove MOSFET using wet etching trench opening technique. IEEE Electron Device Letters 43(10), pp. 1641-1644. (10.1109/LED.2022.3203633)
- Gundimeda, A., Rostami, M., Frentrup, M., Hinz, A., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2022. Influence of AlxGa1-xN nucleation layers on MOVPE-grown zincblende GaN epilayers on 3C-SiC/Si(001). Journal of Physics D: Applied Physics 55(7), article number: 175110. (10.1088/1361-6463/ac4c58)
- Gundimeda, A., Frentrup, M., Fairclough, S. M., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2022. Investigation of wurtzite formation in MOVPE-grown zincblende GaN epilayers on AlxGa1−xN nucleation layers. Journal of Applied Physics 131(11), article number: 115703. (10.1063/5.0077186)
- Dyer, D. et al. 2021. The effect of thermal annealing on the optical properties of Mg-doped zincblende GaN epilayers. Journal of Applied Physics 130(8), article number: 85705. (10.1063/5.0057824)
- Spiridon, B. F. et al. 2021. Method for inferring the mechanical strain of GaN-on-Si epitaxial layers using optical profilometry and finite element analysis. Optical Materials Express 11(6), pp. 1643-1655. (10.1364/OME.418728)
- Church, S. A. et al. 2021. Photoluminescence efficiency of zincblende InGaN/GaN quantum wells. Journal of Applied Physics 129, article number: 175702. (10.1063/5.0046649)
- Vacek, P. et al. 2021. Defect structures in (001) zincblende GaN/3C-SiC nucleation layers. Journal of Applied Physics 129(15), article number: 155306. (10.1063/5.0036366)
- Cuenca, J. A. et al. 2021. Thermal stress modelling of diamond on GaN/III-Nitride membranes. Carbon 174, pp. 647-661. (10.1016/j.carbon.2020.11.067)
- Sun, C. et al. 2020. Thin film gallium nitride (GaN) based acoustofluidic tweezer: modelling and microparticle manipulation. Ultrasonics 108, article number: 106202. (10.1016/j.ultras.2020.106202)
- Ding, B. et al. 2020. Alloy segregation at stacking faults in zincblende GaN heterostructures. Journal of Applied Physics 128(14), article number: 145703. (10.1063/5.0015157)
- Sun, C. et al. 2020. Gallium nitride: a versatile compound semiconductor as novel piezoelectric film for acoustic tweezer in manipulation of cancer cells. IEEE Transactions on Electron Devices 67(8), pp. 3355-3361. (10.1109/TED.2020.3002498)
- Church, S. A. et al. 2020. Stacking fault-associated polarised surface-emitted photoluminescence from zincblende InGaN/GaN quantum wells. Applied Physics Letters 117(3), article number: 32103. (10.1063/5.0012131)
- Wiles, A. A. et al. 2020. A poly(urethane)-encapsulated benzo[2,3-d:6,7-d’]diimidazole organic down-converter for green hybrid LEDs. Materials Chemistry Frontiers 4(3), pp. 1006-1012. (10.1039/C9QM00771G)
- Mandal, S. et al. 2019. Thick, adherent diamond films on AlN with low thermal barrier resistance. ACS Applied Materials and Interfaces 11(43), pp. 40826-40834. (10.1021/acsami.9b13869)
- Lee, L. Y., Frentrup, M., Vacek, P., Massabuau, F. C., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2019. Investigation of MOVPE-grown zincblende GaN nucleation layers on 3C-SiC/Si substrates. Journal of Crystal Growth 524, article number: 125167. (10.1016/j.jcrysgro.2019.125167)
- Lee, L. Y., Frentrup, M., Vacek, P., Kappers, M. J., Wallis, D. J. and Oliver, R. A. 2019. Investigation of stacking faults in MOVPE-grown zincblende GaN by XRD and TEM. Journal of Applied Physics 125, article number: 105303. (10.1063/1.5082846)
- Angioni, E. et al. 2019. Implementing fluorescent MOFs as down-converting layers in hybrid light-emitting diodes. Journal of Materials Chemistry. C 7(8), pp. 2394-2400. (10.1039/C9TC00067D)
- Yi, L., Frentrup, M., Kappers, M., Oliver, R., Humphreys, C. and Wallis, D. 2018. Effect of growth temperature and V/III-ratio on the surface morphology of MOVPE-grown cubic zincblende GaN. Journal of Applied Physics 124, article number: 105302.
- Choi, F. S. et al. 2018. Vertical leakage mechanism in GaN on Si high electron mobility transistor buffer layers. Journal of Applied Physics 124(5), article number: 55702. (10.1063/1.5027680)
- Zaidi, Z. H. et al. 2018. Effects of surface plasma treatment on threshold voltage hysteresis and instability in metal-insulator-semiconductor (MIS) AlGaN/GaN heterostructure HEMTs. Journal of Applied Physics 123(18), article number: 184503. (10.1063/1.5027822)
- Church, S. A. et al. 2018. Effect of stacking faults on the photoluminescence spectrum of zincblende GaN. Journal of Applied Physics 123(18), article number: 185705. (10.1063/1.5026267)
- Tang, F. et al. 2018. Nanoscale structural and chemical analysis of F-implanted enhancement-mode InAlN/GaN heterostructure field effect transistors. Journal of Applied Physics 123(2), article number: 24902. (10.1063/1.5006255)
- Jiang, S. et al. 2017. All-GaN-integrated cascode heterojunction field effect transistors. IEEE Transactions on Power Electronics 32(11), pp. 8743-8750. (10.1109/TPEL.2016.2643499)
- Mandal, S. et al. 2017. Surface zeta potential and diamond seeding on gallium nitride films. ACS Omega 2(10), pp. 7275-7280. (10.1021/acsomega.7b01069)
- Rae, K. et al. 2017. InGaN µLEDs integrated onto colloidal quantum dot functionalized ultra-thin glass. Optics Express 25(16), pp. 19179-19184. (10.1364/OE.25.019179)
- Eblabla, A. M., Li, X., Wallis, D. J., Guiney, I. and Elgaid, K. 2017. GaN on low-resistivity silicon THz high-Q passive device technology. IEEE Transactions on Terahertz Science & Technology 7(1), pp. 93-97. (10.1109/TTHZ.2016.2618751)
- Waller, W. M. et al. 2016. Subthreshold Mobility in AlGaN/GaN HEMTs. IEEE Transactions on Electron Devices 63(5), pp. 1861-1865. (10.1109/TED.2016.2542588)
- Eblabla, A., Li, X., Thayne, I., Wallis, D. J., Guiney, I. and Elgaid, K. 2015. High performance GaN high electron mobility transistors on low resistivity silicon for X -Band Applications. IEEE Electron Device Letters 36(9), pp. 899-901. (10.1109/LED.2015.2460120)
- Waller, W. M. et al. 2015. Interface state artefact in long gate-length AlGaN/GaN HEMTs. IEEE Transactions of Electron Devices 62(8), pp. 2464-2469. (10.1109/TED.2015.2444911)
- Eblabla, A., Wallis, D., Guiney, I. and Elgaid, K. 2015. Novel shielded coplanar waveguides on GaN-on-Low resistivity Si substrates for MMIC applications. IEEE Microwave and Wireless Components Letters 25(7), pp. 427-429. (10.1109/LMWC.2015.2429120)
- Riedel, G. J. et al. 2009. Reducing thermal resistance of AlGaN/GaN electronic devices using novel nucleation layers. IEEE Electron Device Letters 30(2), pp. 103-106. (10.1109/LED.2008.2010340)
- Riedel, G. et al. 2008. Nanosecond timescale thermal dynamics of AlGaN/GaN electronic devices. IEEE Electron Device Letters 29(5), pp. 416-418. (10.1109/LED.2008.919779)
- Sarua, A., Ji, H., Hilton, K. P., Wallis, D., Uren, M. J., Martin, T. and Kuball, M. 2007. Thermal boundary resistance between GaN and substrate in AlGaN/GaN electronic devices. IEEE Transactions of Electron Devices 54(12), pp. 3152-3158. (10.1109/TED.2007.908874)
- Kuball, M. et al. 2007. Time-resolved temperature measurement of AlGaN/GaN electronic devices using micro-raman spectroscopy. IEEE Electron Device Letters 28(2), pp. 86-89. (10.1109/LED.2006.889215)
- Ashley, T. et al. 2007. Heterogeneous InSb quantum well transistors on silicon for ultra-high speed, low power logic applications. Electronics letters 43(14), article number: 777. (10.1049/el:20071335)
- Wallis, D., Keir, A., Emeny, M. and Martin, T. 2001. Measurement of III-V quaternary composition using X-ray diffraction. IEE Proceedings Optoelectronics 148(2), pp. 97-100. (10.1049/ip-opt:20010442)
- Wallis, D., Watson, A. and Mo, N. 1996. Cardiac neurones of automatic ganglia. Microscopy Research and Technique 35(1), pp. 69-79. (10.1002/(SICI)1097-0029(19960901)35:1<69::AID-JEMT6>3.0.CO;2-N)
Conferences
- Roff, C. et al. 2018. Utilization of waveform measurements for degradation analysis of AlGaN/GaN HFETs. Presented at: ARFTG 70th Microwave Measurement Symposium, Tempe, AZ, USA, 27-30 November 20072007 70th ARFTG Microwave Measurement Conference (ARFTG). IEEE, (10.1109/ARFTG.2007.8376173)
- Eblabla, A., Benakaprasad, B., Li, X., Wallis, D., Guiney, I., Humphreys, C. and Elgaid, K. 2017. Passive components technology for THz-Monolithic Integrated Circuits (THz-MIC). Presented at: 18th International Radar Symposium (IRS), 2017, Prague, Czech Republic, 28-30 June 2017Radar Symposium Conference Proceedings. pp. 1-7., (10.23919/IRS.2017.8008166)
- Benakaprasad, B., Eblabla, A., Li, X., Wallis, D., Guiney, I. and Elgaid, K. 2017. Design and performance comparison of various terahertz microstrip antennas on GaN-on-low resistivity silicon substrates for TMIC. Presented at: Microwave Conference (APMC), Asia-Pacific, New Delhi, India, 5-9 Dec 2016Proceedings of the Asia-Pacific Microwave Conference 2016. IEEE, (10.1109/APMC.2016.7931368)
- Benakaprasad, B. et al. 2016. Terahertz monolithic integrated circuits (TMICs) array antenna technology on GaN-on-Low resistivity silicon substrates. Presented at: 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz),, Copenhagen, Denmark, 25-30 Sep 20162016 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz),. IEEE, (10.1109/IRMMW-THz.2016.7758488)
- Jamil, S., Gammon, T., Wallis, D. and Fontaine, M. D. 2016. Standby person for electrical tasks and rescue guidelines for electrical incident victims. Presented at: Petroleum and Chemical Industry Technical Conference (PCIC), Philadelphia, PA, USA, 19-22 Sep 2016. IEEE, (10.1109/PCICON.2016.7589220)
- Chatterjee, I. et al. 2016. Impact of buffer charge on the reliability of carbon doped AlGaN/GaN-on-Si HEMTs. Presented at: 2016 IEEE International Reliability Physics Symposium (IRPS), Pasadena, CA, USA, 17-21 April 20162016 IEEE International Reliability Physics Symposium (IRPS). IEEE pp. 4A41-4A45., (10.1109/IRPS.2016.7574529)
- Wallis, D. 2016. The hazards of risk assessment. Presented at: Electrical Safety Workshop (ESW), Jacksonville, FL, USA, 6-11 March 2016. , (10.1109/ESW.2016.7499706)
- Miaja, P. F. et al. 2016. Modelling the closely-coupled cascode switching process. Presented at: 2016 IEEE Energy Conversion Congress and Exposition (ECCE), Milwaukee, WI, 18-22 September 20162016 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, (10.1109/ECCE.2016.7855268)
- Benakaprasad, B. et al. 2016. Terahertz microstrip single patch antenna technology on GaN-on-Low resistivity silicon substrates for TMIC. Presented at: IET Colloquium on Antennas, Wireless and Electromagnetics, Glasgow, UK, 26 May 2016.
- Eblabla, A., Li, X., Wallis, D., Benakaprasad, B., Guiney, I. and Elgaid, K. 2016. High frequency active and passives devices using GaN on low resistivity silicon. Presented at: ARMMS RF & Microwave Society Conference, Milton Common Nr Thame, UK, 18-19 Apr 2016.
- Elgaid, K. et al. 2016. MMIC-compatible microstrip technology for GaN-HEMTs on low resistivity silicon substrate. Presented at: International Workshop on Nitride Semiconductors (IWN 2016), Orlando, FL, USA, 2-7 Oct 2016.
- Ashley, T. et al. 2010. High-performance InSb based quantum well field effect transistors for low-power dissipation applications. Presented at: 2009 IEEE International Electron Devices Meeting (IEDM), Baltimore, MD, USA, 7-9 December 20092009 IEEE International Electron Devices Meeting (IEDM). IEEE pp. 1., (10.1109/IEDM.2009.5424207)
- Janssen, J. et al. 2009. X-Band GaN SPDT MMIC with over 25 watt linear power handling. Presented at: European Microwave Integrated Circuit Conference, 2008, Amsterdam, The Netherlands, 27-28 October 20092008 European Microwave Integrated Circuit Conference. IEEE, (10.1109/EMICC.2008.4772261)
- Radosavljevic, M. et al. 2008. High-performance 40nm gate length InSb p-channel compressively strained quantum well field effect transistors for low-power (VCC=0.5V) logic applications. Presented at: IEEE International Electron Devices Meeting, San Francisco, CA, 15-17 Dec 2008. , (10.1109/IEDM.2008.4796798)
- Ashley, T. et al. 2007. Indium antimonide based quantum well FETs for ultra-high speed electronics. Presented at: 64th Device Research Conference, State College, PA, 26-28 June 2006. pp. 201., (10.1109/DRC.2006.305056)
- Wallis, D. 2006. Class F at class B temperatures is it time for a change?. Presented at: Conference Record of the 2006 IEEE International Symposium on Electrical Insulation, 2006, Toronto, Ont., Canada, 11-14 June 2006. , (10.1109/ELINSL.2006.1665243)
- Ashley, T. et al. 2006. Indium antimonide based technology for RF applications. Presented at: Compound Semiconductor Integrated Circuit Symposium, San Antonio, TX, 12-15 Nov 2006. , (10.1109/CSICS.2006.319918)
- Uren, M. et al. 2006. Control of Short-Channel Effects in GaN/AlGaN HFETs. Presented at: 1st European Microwave Integrated Circuits Conference, Manchester, UK, 10-13 Sept 20062006 European Microwave Integrated Circuits Conference. IEEE pp. 65-65., (10.1109/EMICC.2006.282751)
- Datta, S. et al. 2005. 85nm gate length enhancement and depletion mode InSb quantum well transistors for ultra high speed and very low power digital logic applications. Presented at: IEEE International Electron Devices Meeting, Washington DC, 5 Dec 2005Electron Devices Meeting, 2005. IEDM Technical Digest. IEEE International. IEEE, (10.1109/IEDM.2005.1609466)
Ymchwil
ID | Teitl | Cyllidwr | Dyddiadau | Gwerth | PI / CoI | ||
EP/R01146X/1 |
| EPSRC | 2/18 –1/21 | £493k | DP | ||
EP / R03480X/1 | 'Hetero-brint': Dull cyfannol o drosglwyddo argraffu ar gyfer integreiddio heterogenaidd mewn gweithgynhyrchu | EPSRC | 6/18 – 5/23 | £5.5M | Coi | ||
EP / P00945X/1 | Electroneg Microdon GaN-Diamond Integredig: O ddeunyddiau, transistorau i MMICs | EPSRC | 1/17 - 12/21 | £4.3M | Coi | ||
EP/N017927/1 | Integreiddio cylchedau RF gyda Cyflymder Uchel GaN Newid ar Swbstradau Silicon | EPSRC | 5/16 - 4/19 | £2.4M | Coi | ||
EP / P03036X/1 | Fertigol ciwbig GaN LEDs ar swbstradau 3C-SiC 150mm | IUK | 2/17 - 7/18 | £208k | DP | ||
EP / N01202X/2 | Cymrodoriaeth Gweithgynhyrchu EPSRC yn Gallium Nitride | EPSRC | 3/16 - 2/21 | £1.3M | DP | ||
103446 | GaNSense | IUK | 10/17-12/18 | £306k | Coi | ||
EP / S01005X/1 | Non-llinellol (signal mawr) Dyfeisiau tonnau milimetr, Cylchedau a Systemau Cyfleuster Nodweddu Ar-Wafer | EPSRC | 10/18 - 9/19 | £1.4M | Coi | ||
EEF6084 | Grant Entrepreneuriaid Ynni | BEIS | 10/18 - 9/20 | £690k | DP |
Bywgraffiad
Ar hyn o bryd mae gen i gadeirydd ymuno mewn lled-ddargludyddion cyfansawdd rhwng Prifysgolion Caerdydd a Chaergrawnt ac rwyf hefyd yn gymrawd EPSRC Manufacturing. Cyn ymgymryd â'm swydd academaidd bresennol, cefais fy nghyflogi gan Plessey Semiconductors ac roeddwn yn gyfrifol am sefydlu eu gallu i dyfu GaN a throsglwyddo technoleg technoleg y dechnoleg twf GaN on Si a brynwyd ganddynt o Brifysgol Caergrawnt i alluogi lansio eu cynhyrchion GaN on Si LED. Cyn hynny, gweithiais i QinetiQ Plc am 14 mlynedd ac roeddwn yn arweinydd technegol ar gyfer eu gallu i dyfu a nodweddu GaN. Roedd y rôl hon yn canolbwyntio'n bennaf ar ddatblygu dyfeisiau RF sy'n seiliedig ar GaN. Derbyniais fy PhD mewn Ffiseg Microstrwythurol o Brifysgol Caergrawnt.
Meysydd goruchwyliaeth
Mae gen i ddiddordeb mewn goruchwylio myfyrwyr PhD ym maes
- Twf GaN
- Nodweddiad GaN
- Dyfeisiau GaN
Contact Details
+44 29208 79065
Adeiladau'r Frenhines -Adeilad y De, Ystafell Ystafell S/1.08, 5 The Parade, Heol Casnewydd, Caerdydd, CF24 3AA
Themâu ymchwil
Arbenigeddau
- Lled-ddargludyddion cyfansawdd