Ga0.47In0.53As field-effect transistors with a lattice-mismatched reduced leakage current GaAs gate

A lattice-mismatched GaAs gate Ga0.47In0.47As field-effect transistor (LMG-FET) with significantly reduced reverse gate leakage current is reported. The mechanism responsible for this reduction by over two orders of magnitude over previous work has been identified; it is attributed to the confinement of misfit dislocations originating at the GaAs/InGaAs interface. The LMG-FET had a gate leakage current of 0.48 ?A at ? V, and an extrinsic DC transconductance of 104 mS/ mm for a 1.4 ?m gate length and 240 ?m gate width. Further refinements in crystal growth should lead to even lower values of leakage current, making this technology attractive for high-speed logic, as well as lightwave optoelectronic integration.