Hydrogen diffusion inGaAs1−xNx

Abstract

Hydrogen (or deuterium) incorporation in dilute nitride semiconductors modifies dramatically the electronic and structural properties of the crystal through the creation of nitrogen-hydrogen complexes. In this work, we investigate how the formation and dissociation of such complexes rule the diffusion of deuterium in ${\text{GaAs}}_{1\ensuremath{-}x}{\text{N}}_{x}$. The concentration depth profile of deuterium is determined by secondary ion mass spectrometry under a wide range of experimental conditions that comprise different N concentrations ($x=0.09%$, 0.40%, 0.70%, and 1.5%) and D irradiation temperatures (${T}_{\text{D}}=200$, 250, 300 and $350\text{ }\ifmmode^\circ\else\textdegree\fi{}\text{C}$). The experimental data are successfully reproduced by a diffusion model in the presence of strong D trapping. In particular, the deuterium diffusion and capture rate coefficients are determined, and a minimum decay length of the deuterium forefront is found at low ${T}_{\text{D}}$ $(l250\text{ }\ifmmode^\circ\else\textdegree\fi{}\text{C})$ and high $x$ $(g0.7%)$. These parameters set the experimental conditions within which a nanostructuring of the physical properties of ${\text{GaAs}}_{1\ensuremath{-}x}{\text{N}}_{x}$ is attainable.