The effects of hot-wire atomic hydrogen on amorphous silicon

Amorphous silicon is strongly affected by exposure to hot-wire atomic hydro gen. In this study we show the various effects of atomic hydrogen on thin h ydrogenated amorphous silicon films. The as-deposited material is of high q uality. It appears possible to increase the hydrogen concentration by a fac tor of 2. At least 80% of the additional hydrogen atoms are bonded to silic on. Prolonged hydrogen loading causes total removal of the amorphous silico n layer by etching. An underlying crystalline silicon substrate is etched i nhomogeneously. We link these various effects, describe a probable mechanis m, and suggest processes taking place during hot-wire deposition. Atomic hy drogen appears to play a major role during film growth. (C) 2001 American I nstitute of Physics.