Substrate-affected instability in accumulation-mode InP metal-insulator-semiconductor field-effect transistor

The mechanism for drain current drift in accumulation-type InP metal-insulator-semiconductor field-effect transistor has in the past several years been attributed to oxide traps, interface states, and bulk traps. In this study we have found that deep levels in the semi-insulating InP substrate material can in some cases dominate the current drift of the accumulation-mode metal-insultor-semiconductor field-effect transistor. Iron, which is a deep-level acceptor, when present in large concentrations in semi-insulating InP substrate material, appears to provide poor transistor properties and a large long-term current drift.