Defect formation in a-Si:H

The bulk chemical processes responsible for defect equilibria in hydrogenated amorphous silicon (a-Si:H) are examined. Thermodynamic analyses of the corresponding chemical reactions are shown to account quantitatively for the observed defect-state-energy distribution and dependence of the defect concentration on temperature and Fermi energy. The dependence of a-Si:H defect properties on growth conditions is addressed.