Hydrogen bonding configurations in silicon nitride films prepared by plasma-enhanced deposition

Abstract

Hydrogen chemical bonding configurations in amorphous silicon nitride films prepared by plasma-enhanced chemical vapor deposition are determined for the first time. This is accomplished by measuring the difference spectra between the absorption spectrum of an annealed or a hydrogen implanted film and that of a reference film, mostly as-grown film. Three- and two-bonding configurations for Si-hydrogen and N-hydrogen bonds are separated and assigned to Si-H(2120 cm−1), Si-H2 and/or (Si-H2)n chains (2180 cm−1), Si-H3(2255 cm−1), N-H(3320 cm−1), and N-H2(3280 and 3345 cm−1), respectively. Si-H2 bonds are the most thermally stable and N-H2 bonds are more thermally stable than N-H bonds. It is found that N-H bonds form the hydrogen bonding in the films.