In/sub 0.52/Al/sub 0.48/As/In/sub 0.53/Ga/sub 0.47/As MSM photodetectors and HEMT's grown by MOCVD on GaAs substrates

The authors report the first demonstration of In/sub 0.52/Al/sub 0.48/As/In/sub 0.53/Ga/sub 0.47/As metal-semiconductor-metal (MSM) photodetectors and high-electron-mobility transistors (HEMTs) grown on GaAs substrates by organometallic chemical vapor deposition. Both photodetectors and transistors showed no degradation in performance compared to devices simultaneously grown on InP substrates. The photodetectors exhibited a responsivity of 0.45 A/W and leakage current of 10 to 50 nA. The HEMTs with a gate length of 1.0 mu m showed a transconductance as high as 250 mS/mm, and f/sub T/ and f/sub max/ of 25 and 70 GHz, respectively.<
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