AlGaN/GaN HEMTs on resistive Si(111) substrate grown by gas-source MBE

CNRS, Valbonne
Electronics Letters (Impact Factor: 1.07). 02/2002; DOI: 10.1049/el:20020060
Source: IEEE Xplore

ABSTRACT Al0.3Ga0.7N/GaN high electron mobility
transistor (HEMT) structures have been grown on resistive Si(111)
substrate by molecular beam epitaxy (MBE) using ammonia
(NH3). The use of an AlN/GaN intermediate layer allows a
resistive buffer layer to be obtained. High sheet carrier density and
high electron mobility arc obtained in the channel. A device with 0.5
μm gate length has been realised exhibiting a maximum extrinsic
transconductance of 160 mS/mm and drain-source current exceeding 600
mA/mm. Small-signal measurements show ft of 17 GHz and
fmax of 40 GHz

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