Thermal stability of p-type doped amorphous silicon suboxides

Abstract We investigate the effects of thermal annealing on the optical and electrical properties of p-type doped amorphous silicon suboxide (a-SiO x :H) samples prepared by plasma enhanced chemical vapour deposition (PECVD). Changes in the microscopic structure of the amorphous network upon thermal annealing at low temperatures ( 550 K) leads to an effusion of hydrogen, thereby reducing the optical bandgap, E 04 , of the samples. The dependence of E 04 on the hydrogen content for amorphous suboxides with different oxygen content is found to be similar to that of amorphous silicon.