BACK-GATING EFFECTS ON THE GA0.1IN0.8P INP/INGAAS HIGH-ELECTRON-MOBILITY TRANSISTOR/

Pseudomorphic GaInP/InP/InGaAs high electron mobility transistors (HEM T) with improved Schottky contacts and excellent electrical characteri stics are grown by low-pressure metal-organic chemical vapor depositio n (LP-MOCVD) on the InP substrate. These HEMTs with 1.71 mu m gate len gth have an average extrinsic transconductance of 225 mS/mm. The back- gating effects of this device structure are investigated for the first time in this structure. Both positive and negative bias are applied t o the ohmic and Schottky back-gate contacts of these devices. The posi tive back-gate bias has no effect on the drain current or the output t ransconductances of these devices. The effect of the negative back-gat e bias is very similar to that when negative bias is applied on the ga te of these HEMTs.