Deuterium passivation of electrically active defects in nonintentionally doped n-GaN

Abstract

Deuterium diffusion was achieved in nonintentionally doped n-GaN layers, grown by metal organic chemical vapor deposition, at 460°C and a power density of 1.0Wcm−2. A deuterium diffusion mechanism was observed yielding concentrations around 1018cm−3 in the surface region following the (Dt)1∕2 diffusion law. A second mechanism displaying an abnormally high diffusion coefficient, probably occurring along threading dislocations, was observed. The fast diffusing deuterium traps electrons and passivates residual acceptors, decreasing the electron concentration from 1016to1015cm−3 and increasing the electron mobility from 10to320cm2V−1s−1, producing better material for electronic devices.