0.065 mu m gate InGaP/InGaAs/GaAs pseudomorphic HEMTs with highly-doped 11.5 nm thick InGaP electron supply layers

We demonstrated that the thinning of InGaP electron supply layers is very effective in reducing short channel effects, even for 0.065 mu m gate InGaP/InGaAs/GaAs pseudomorphic HEMTs. By thinning the InGaP electron supply layer to 11.5 nm with a high doped density of 5 x 10(18) cm(-3), we were able to minimize the threshold voltage shift to less than 0.15 V compared to 1.65 mu m gate length HEMTs. We could also increase the extrinsic transconductance (g(m)) by thinning the InGaP electron supply layer. We observed no degradation of gate leakage characteristics, regardless of such a highly-doped, thin InGaP layer. The 0.065 mu m gate length HEMT exhibits an extrinsic transconductance (g(m)) of 585 mS mm(-1), a current gain cutoff frequency (f(T)) of 110 GHz and a maximum oscillation frequency (f(max)) of 150 GHz. (C) 1997 Elsevier Science Ltd.