Search Results - "Birbeck, J.C.H."

Measurement of temperature in active high-power AlGaN/GaN HFETs using Raman spectroscopy by Kuball, M., Hayes, J.M., Uren, M.J., Martin, I., Birbeck, J.C.H., Balmer, R.S., Hughes, B.T.

“…We report on the noninvasive measurement of temperature, i.e., self-heating effects, in active AlGaN/GaN HFETs grown on sapphire and SiC substrates…”
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Integration of a superlattice limiter into the HBT emitter for improved operational reliability by Hayes, D.G., Higgs, A.W., Smith, G.W., Birbeck, J.C.H., Wilding, P.J.

“…A common problem limiting the output power of multiple finger heterojunction bipolar transistors (HBT's) is nonuniform current flow in the fingers, resulting…”
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A phased array optical scanning (PHAROS) device used as a 1-to-9 way switch by Heaton, J.M., Wight, D.R., Parker, J.T., Hughes, B.T., Birbeck, J.C.H., Hilton, K.P.

“…An optical switch is demonstrated which uses a phased array of 30 closely spaced, individually addressed electrooptic AlGaAs-GaAs waveguides to focus and steer…”
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In situ optical monitoring of AlGaN thickness and composition during MOVPE growth of AlGaN/GaN microwave HFETs by Balmer, R.S., Pickering, C., Kier, A.M., Birbeck, J.C.H., Saker, M., Martin, T.

“…Real-time spectral reflectometry has been implemented to monitor the MOVPE growth of AlGaN/GaN microwave HFET structures. The aim is to monitor and control the…”
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Optimization of deep-etched, single-mode GaAs-AlGaAs optical waveguides using controlled leakage into the substrate by Heaton, J.M., Bourke, M.M., Jones, S.B., Smith, B.H., Hilton, K.P., Smith, G.W., Birbeck, J.C.H., Berry, G., Dewar, S.V., Wight, D.R.

“…This paper presents a detailed experimental and theoretical study of the properties of deep-etched GaAs-AlGaAs optical waveguides designed using a version of…”
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AlGaN/GaN microwave power transistors for S band by Uren, M.J., Hughes, B.T., Hayes, D.G., Hilton, K.P., Martin, T., Balmer, R.S., Birbeck, J.C.H., Davies, R.A.

“…Multifinger power transistors have been fabricated using AlGaN/GaN grown on insulating SiC by MOVPE. Using a 1 /spl mu/m gate length device, f/sub T/ of 10 GHz…”
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