In0.53Ga0.47As MOS‐HEMTs on GaAs and Si substrates grown by MOCVD

High-performance In0.53Ga0.47As metal-oxide-semiconductor high-electron-mobility-transistors (MOS-HEMTs) on GaAs substrates grown by metal organic chemical vapor deposition (MOCVD) are demonstrated. A low-temperature process has been developed to achieve low contact resistances while maintaining the quality of the dielectric/III–V interface. Atomic-layer-deposited Al2O3 was used as the gate dielectric on top of a δ-doped In0.51Al0.49As/In0.53Ga0.47As metamorphic heterostructure. A 1-µm gate-length device exhibits a maximum drain current of 646 mA/mm and an extrinsic peak transconductance of 575 mS/mm, respectable values for III–V metal-oxide-semiconductor field-effect transistors (MOSFETs) on GaAs substrates. In addition, preliminary results of In0.53Ga0.47As MOS-HEMTs on Si substrates, also grown by MOCVD, are presented for comparison.