Bond Densities And Electronic Structure Of Amorphous Sinx:h

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We present a study of amorphous hydrogenated silicon-nitrogen alloys (a-SiNx:H, 0 x1, Si-N bonds increase at the expense of both Si-Si and Si-H bonds; however, this is not enough to saturate the three N valencies with Si and some N-H and possibly N-N bonds begin to appear. The opening of the optical gap occurs at x 1.1 when the ratio of the densities of Si-Si bonds to Si-N bonds has fallen below 0.10. Near stoichiometry, substantial amounts of Si-Si and N-H bonds are observed. The possibility of segregation into pure silicon and stoichiometric silicon nitride is discussed by analyzing the Si 2p line shape. A linear relationship between the Si 2p chemical shift and the mean number of N-atom nearest neighbors of Si is observed; a charge transfer of 0.35e per Si-N bond is determined. © 1990 The American Physical Society.42956775684CAPES; Conselho Nacional de Desenvolvimento Científico e Tecnológico; CNPq; Conselho Nacional de Desenvolvimento Científico e Tecnológico; FAPESP; Conselho Nacional de Desenvolvimento Científico e TecnológicoFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP