Statistical study of the effect of interface charge fluctuations in HEMTs using a 3D simulator

The intrinsic parameter fluctuations associated with the discreteness of charge and matter become an important factor when the semiconductor devices are scaled to nanometre dimensions. The interface charge in the recess regions of high electron mobility transistors (HEMTs) has a considerable effect on the overall device performance. We have employed a 3D parallel drift-diffusion device simulator to study the impact of interface charge fluctuations on the I-V characteristics of nanometre HEMTs. For this purpose, two devices have been analysed, a 120 nm gate length pseudomorphic HEMT with an In0.2Ga0.8As channel and a 50 nm gate length InP HEMT with an In0.7Ga0.3As channel.

keywords: Intrinsic parameter fluctuations, Interface charge, HEMT devices, Drift-diffusion ,3D simulations