Role of Atomic Hydrogen During Growth of Hydrogenated Amorphous Silicon in the “Chemical Annealing”

Abstract

In our previous paper, we proposed a novel preparation technique termed “Chemical annealing” to make a rigid and stable Si-network. In this letter, with the aim of the understanding the role of atomic hydrogen on the growing surface, systematic studies were made on the concentrations of H and D for the chemically annealed films made by SiH₄ and atomic deuterium system as a function of the deposition time in one cycle, the annealing time and the substrate temperature. In the chemically annealed film, the structural relaxation is thermally activated with an activation energy of 0.3 eV. The role of atomic hydrogen is the creation of dangling bonds in the top surface for the enhancement of a cross linking reaction; passivation of dangling bond and break of weak Si-Si bonds for the rearrangement of Si-network. In comparison with the post-deutrization results, the role of atomic hydrogen in the “Chemical annealing” is discussed.