An In
0.52Al
0.48As/n
+-In
0.53Ga
0.47As MIS-type field-effect transistor (FET) with a channel doped at a 7 × 10
17cm
-3level has been fabricated on an InP substrate. A device with a 2-µm channel length has yielded a maximum transconductance of 152 mS/mm,

GHz, and

GHz. At 10 GHz, the maximum available gain is 17.4 dB. The performance of this device shows that heavily doped channel FET\´s are very promising for high-frequency operation.