Effects of annealing on hydrogen microstructure in boron-doped and undoped rf-sputter-deposited amorphous silicon

Abstract

A detailed study of changes in hydrogen microstructure in rf-sputter-deposited undoped and boron-doped hydrogenated amorphous silicon was undertaken. The boron-doped samples were prepared under identical conditions with the same hydrogen content, and then characterized by IR absorption and ${}_{}{}^1{}_{}{}^{}\mathrm{H}$ NMR before and after annealing. It is found that an increase in the boron concentration leads to increased segregation of hydrogen. Annealing leads to evolution of the hydrogen microstructure. This change, however, depends on the boron content of the films. After a moderate anneal, the hydrogen microstructure is found to evolve to the same state and seems to be independent of the boron content of the films.