Strained germanium-tin (GeSn) p-channel metal-oxide-semiconductor field-effect-transistors (p-MOSFETs) with ammonium sulfide passivation

Abstract

High-mobility strained Ge0.958Sn0.042 p-channel metal-oxide-semiconductor field-effect-transistors (p-MOSFETs) with ammonium sulfide [(NH4)2S] surface passivation were demonstrated. A ∼10 nm thick fully-strained single crystalline GeSn layer was epitaxially grown on Ge (100) substrate as the channel layer. (NH4)2S surface passivation was performed for the GeSn surface, followed by gate stack formation. Ge0.958Sn0.042 p-MOSFETs with (NH 4)2S passivation show decent electrical characteristics and a peak effective mobility of 509 cm2/V s, which is the highest reported peak mobility obtained for GeSn channel p-MOSFETs so far. © 2013 Elsevier Ltd. All rights reserved.