AN IMPROVED INVERTED DELTA-DOPED GAAS INGAAS PSEUDOMORPHIC HETEROSTRUCTURE GROWN BY MOCVD

This letter demonstrates a novel GaAs/In0.25 Ga0.75As/GaAs pseudomorph ic heterostructure with delta-doping on the buffer prepared by low-pre ssure metalorganic chemical vapor deposition (LP-MOCVD). The proposed device with a 1.5x80 mum2 gate reveals an extrinsic transconductance a s high as 250 (305) mS/mm and a saturation current density as high as 790 (890) mA/mm at 300 (77) K. Significantly improvements on forward g ate voltage swing (up to 3 V) and on reverse leakage current (smaller than 10 muA/mm at -6.5 V) are demonstrated due to inverted parallel co nduction (IPC) effect. We also carried out secondary-ion mass spectrom etry (SIMS) profiles to confirm the quality of the proposed device.