Growth of hydrogenated amorphous silicon and its alloys

Significant advances have been made in characterizing, optimizing, and understanding plasma-enhanced chemical vapor deposition of hydrogenated amorphous silicon (a-Si:H) and its alloys, a-Si1−xCx:H and a-Si1-xGex:H. In particular, progress has been made in developing materials with improved properties, stability, and device performance through H2 dilution of SiH4, controlled ion bombardment, and atomic H processing. Highly sensitive probes of the microstructure and bonding,including scanning tunneling microscopy, real time and in situ infrared and optical spectroscopies, and small-angle X-ray scattering, have led to a better understanding of the physical origins of these improvements.