Annealing-temperature influence on the dispersive diffusion of hydrogen in undoped<i>a</i>-Si:H

Abstract

We have measured by the method of elastic-recoil detection analysis the variation of the dispersion parameter \ensuremath{\alpha} of hydrogen diffusion in undoped a-Si:H as a function of the annealing temperature ${\mathit{T}}_{\mathit{a}}$ between 350 and 470 \ifmmode^\circ\else\textdegree\fi{}C. We found that \ensuremath{\alpha} increases with ${\mathit{T}}_{\mathit{a}}$. We suggest a mechanism which can explain this new result, as well as the variation of \ensuremath{\alpha} with the film-deposition temperature reported earlier.