Influence of hydrogen on the performance of magnetron-sputtered amorphous hydrogenated silicon field-effect transistors

Abstract
The characteristics of amorphous hydrongenated silicon field-effect transistors (a-Si:H FET’s) depend strongly on the partial hydrogen pressure during rf magnetron sputtering of the active material. The density of states near midgap can be reduced to around 8×1016 cm−3 eV−1, and, as a consequence, the on-off drain current ratio increases by more than four orders of magnitude at a gate voltage lower than 15 V. The performance of such FET’s, in particular their output characteristics, is found to be comparable to that of glow-discharge produced devices.