Demonstration of Ga/sub 2/O/sub 3/(Gd/sub 2/O/sub 3/)/InGaAs enhancement-mode n-channel MOSFETs

We have investigated InGaAs MOSFETs using a mixture of Ga/sub 2/O/sub 3/ and Gd/sub 2/O/sub 3/ as the gate dielectric evaporated from a high-purity single-crystal Gd/sub 3/Ga/sub 5/O/sub 12/ source. We report the first Ga/sub 2/O/sub 3/(Gd/sub 2/O/sub 3/) insulated gate n-channel enhancement-mode In/sub 0.53/Ga/sub 0.47/As MOSFETs on an InP semi-insulating substrate. A 0.75/spl times/50 /spl mu/m/sup 2/ gate device exhibits an extrinsic transconductance of 190 mS/mm which is an order of magnitude improvement over previously reported values. The current gain cut-off frequency and the maximum frequency of oscillation are 6.8 and 7.8 GHz, respectively.