Properties of amorphous semiconducting multilayer films

The structural, optical, and electrical properties of amorphous multilayer films containing up to 180 double layers of a-Si:H/a-SiNx and a-Si:H/a-SiOx were studied. For a-Si:H layer thickness d >100 A the transport properties are dominated by space-charge doping with a-SiNx positive and a-SiOx negatively charged. For d A quantum-well effects increase the optical and electrical gaps. A d =12 A multilayer film shows no evidence for the predicted loss of extended states in two-dimensional disordered systems.