Amorphous-Silicon Thin-Film Transistors Using Chemical Vapor Deposition of Disilane

Amorphous silicon layers have been deposited by low pressure chemical vapour deposition at 450°C using disilane as the only source gas. Simple inverted staggered thin-film transistors were made with thermal silicon dioxide as the gate insulator. Field-effect mobilities for electrons and holes were 1.4 cm 2 /V ·s and 0.1 cm 2 /V ·s, respectively. In order to obtain these high mobilities the transistor structures were carefully annealed in a hydrogen-radical rich ambient.