Search Results - "Maclean, J.O."

Reducing Thermal Resistance of AlGaN/GaN Electronic Devices Using Novel Nucleation Layers by Riedel, G.J., Pomeroy, J.W., Hilton, K.P., Maclean, J.O., Wallis, D.J., Uren, M.J., Martin, T., Forsberg, U., Lundskog, A., Kakanakova-Georgieva, A., Pozina, G., Janzen, E., Lossy, R., Pazirandeh, R., Brunner, F., Wurfl, J., Kuball, M.

“…Currently, up to 50% of the channel temperature in AlGaN/GaN electronic devices is due to the thermal-boundary resistance (TBR) associated with the nucleation…”
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Analysis of DC-RF Dispersion in AlGaN/GaN HFETs Using RF Waveform Engineering by Roff, C., Benedikt, J., Tasker, P.J., Wallis, D.J., Hilton, K.P., Maclean, J.O., Hayes, D.G., Uren, M.J., Martin, T.

“…This paper describes how dc-radio-frequency (RF) dispersion manifests itself in AlGaN/GaN heterojunction field-effect transistors when the devices are driven…”
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Nanosecond Timescale Thermal Dynamics of AlGaN/GaN Electronic Devices by Riedel, G.J., Pomeroy, J.W., Hilton, K.P., Maclean, J.O., Wallis, D.J., Uren, M.J., Martin, T., Kuball, M.

“…Time-resolved Raman thermography, with a temporal resolution of , was used to study the thermal dynamics of AlGaN/GaN electronic devices (high-electron…”
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Vertically tapered epilayers for low-loss waveguide-fiber coupling achieved in a single epitaxial growth run by Balmer, R.S., Heaton, J.M., Maclean, J.O., Ayling, S.G., Newey, J.P., Houlton, M., Calcott, P.D.J., Wight, D.R., Martin, T.

“…Next-generation optical-communications systems require on-wafer integration of active and passive opto-electronic components to increase operating speed and…”
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Time-Resolved Temperature Measurement of AlGaN/GaN Electronic Devices Using Micro-Raman Spectroscopy by Kuball, M., Riedel, G.J., Pomeroy, J.W., Sarua, A., Uren, M.J., Martin, T., Hilton, K.P., Maclean, J.O., Wallis, D.J.

“…We report on the development of time-resolved Raman thermography to measure transient temperatures in semiconductor devices with submicrometer spatial…”
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Pressure studies of conduction-band N-pair-state mixing in dilute GaAs 1− xN x alloys by Weinstein, B.A, Stambach, S.R, Ritter, T.M, Maclean, J.O, Wallis, D.J

“…High-pressure photoluminescence (PL) experiments (at 9 K ) are reported for GaAs 1− x N x /GaAs quantum wells having N compositions ( x=0.0025, 0.004) in the…”
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Nitrogen incorporation into GaAs(N), Al 0.3Ga 0.7As(N) and In 0.15Ga 0.85As(N) by chemical beam epitaxy (CBE) using 1,1-dimethylhydrazine by Maclean, J.O., Wallis, D.J., Martin, T., Houlton, M.R., Simons, A.J.

“…Nitrogen incorporation in the growth of epitaxial GaN x As (1− x) by chemical beam epitaxy (CBE) using 1,1-dimethylhydrazine (DMHy) was compared, for the first…”
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Nitrogen incorporation into GaAs(N), Al0.3Ga0.7As(N) and In0.15Ga0.85As(N) by chemical beam epitaxy (CBE) using 1,1-dimethylhydrazine by Maclean, J.O., Wallis, D.J., Martin, T., Houlton, M.R., Simons, A.J.

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Pressure studies of conduction-band N-pair-state mixing in dilute GaAs1−xNx alloys by Weinstein, B.A, Stambach, S.R, Ritter, T.M, Maclean, J.O, Wallis, D.J

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Utilization of waveform measurements for degradation analysis of AlGaN/GaN HFETs by Roff, Chris, Bennedikt, J., Tasker, Paul J., Wallis, D.J., Hilton, K.P., Maclean, J.O., Hayes, D.G., Uren, M. J., Martin, T.

“…This paper employs, for the first time, RF waveform engineering to monitor device degradation over an RF "burn in" period. Measured RF current and voltage…”
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Calibration of SIMS measurements of unintentional oxygen concentrations in Al/sub 0.3/Ga/sub 0.7/N/sub y/As/sub (1-y)/ and assessment of the purity of 1,1-dimethylhydrazine by Maclean, J.O., Simons, A.J., Houlton, M.R., Martin, T., Birbeck, J.

“…There is significant commercial interest in 1.3 /spl mu/m dilute nitride-based laser devices. Such devices rely on low concentrations of nonradiative centres…”
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Integrated laser/waveguide by shadow-masked selective area epitaxy using chemical beam epitaxy (CBE) by Balmer, R.S, Martin, T, Kane, M.J, Maclean, J.O, Whitaker, T.J, Ayling, S.G, Calcott, P.D.J, Houlton, M, Newey, J.P, O'Mahony, S.J

“…An integration concept which involves the selective deposition of quantum wells in spatially selected areas of a wafer and in the middle of a waveguide…”
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X-Band GaN SPDT MMIC with over 25 Watt Linear Power Handling by Janssen, J., van Heijningen, M., Hilton, K.P., Maclean, J.O., Wallis, D.J., Powell, J., Uren, M., Martin, T., van Vliet, F.

“…Single pole double throw (SPDT) switches are becoming more and more key components in phased-array radar transmit/receive modules. An SPDT switch must be able…”
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High-performance InSb based quantum well field effect transistors for low-power dissipation applications by Ashley, T., Emeny, M.T., Hayes, D.G., Hilton, K.P., Jefferies, R., Maclean, J.O., Smith, S.J., Tang, A.W.-H., Wallis, D.J., Webber, P.J.

“…Indium antimonide (InSb) has the highest electron mobility and saturation velocity of any conventional semiconductor, giving potential for a range of analogue…”
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Optimising AIGaN/GaN HFET designs for high efficiency by Roff, C., Sheikh, A., Benedikt, J., Tasker, P.J., Hilton, K.P., Maclean, J.O., Hayes, D.G., Uren, M.J., Martin, T.

“…This paper uses measured waveforms to demonstrate how to optimise GaN HFET PA designs in order to achieve high power and high efficiency. Efficiency values of…”
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Control of Short-Channel Effects in GaN/AlGaN HFETs by Uren, M.J., Hayes, D.G., Balmer, R.S., Wallis, D.J., Hilton, K.P., Maclean, J.O., Martin, T., Roff, C., McGovern, P., Benedikt, J., Tasker, P.J.

“…GaN/AlGaN HEMTs can suffer from short channel effects as a result of insufficient buffer doping. The paper show that controlled iron doping of the GaN buffer…”
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Detailed Analysis of DC-RF Dispersion in AlGaN/GaN HFETs using Waveform Measurements by Roff, C., McGovern, P., Benedikt, J., Tasker, P.J., Balmer, R.S., Wallis, D.J., Hilton, K.P., Maclean, J.O., Hayes, D.G., Uren, M.J., Martin, T.

“…Detailed time-domain IV waveforms at RF frequencies are employed for characterisation of AlGaN/GaN HFETs in order to steer and advance device development. The…”
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GaN H-FET development at QinetiQ by Martin, T., Uren, M.J., Balmer, R.S., Soley, D., Wallis, D.J., Hilton, K.P., Maclean, J.O., Munday, A.G., Hydes, A.J., Hayes, D.G., Oxley, C.H., McGovern, P., Tasker, P.J.

“…The AlGaN/GaN HFET project at QinetiQ has the capability to grow high quality layers using MOVPE, fabricate HFETs with 0.8 and 0.25 /spl mu/m gate length and…”
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