Modeling the diffusion of hydrogen in GaAs

摘要

Concentration depth profiles of carriers (or of electrically active defects) and/or deuterium in GaAs following exposure to a hydrogen plasma (or, in one case, to molecular hydrogen) are fit using a simple diffusion model with secondhyphen;order reactions. We find that (1) the activation energy for hydrogen diffusion and the dissociation energies of hydrogenhyphen;defect complexes are dependent on the concentration of hydrogen, (2) there is no molecular hydrogen formation and no fasthyphen;diffusing species of hydrogen away from the nearhyphen;surface region, and (3) atomic hydrogen can inhyphen;diffuse and passivate EL2 defects when semihyphen;insulating GaAs is annealed at a high temperature in a molecular hydrogen ambient.