Lg = 100 nm InAs PHEMTs on InP substrate with record high frequency response

A report is presented on 100 nm and 200 nm InAs PHEMTs on an InP substrate with a record f_T performance. This result was obtained by reducing a parasitic delay associated with the extrinsic gate capacitances of the device, as well as by using an InAs sub-channel to improve carrier transport properties. In particular, a 100 nm InAs PHEMT exhibits excellent performance, such as g_m,max=2 S/mm, f_T=421=GHz and f_max=620=GHz at V_DS=0.7 V. The device also shows a well-balanced f_T and f_max in excess of 400 GHz, even at V_DS=0.5 V. In addition, the device gains about 70 = improvement in f_T as L_g shrinks down from 200 to 100 nm. The results obtained in this work should make this technology of great interest to a multiplicity of applications and guide a realistic path in trying to achieve a 1 THz f_T from III-V HEMTs in the future.