Evolution of deep centers in GaN grown by hydride vapor phase epitaxy

Deep centers and dislocation densities in undoped n GaN, grown by hydride v apor phase epitaxy (HVPE), were characterized as a function of the layer th ickness by deep level transient spectroscopy and transmission electron micr oscopy, respectively. As the layer thickness decreases, the variety and con centration of deep centers increase, in conjunction with the increase of di slocation density. Based on comparison with electron-irradiation induced ce nters, some dominant centers in HVPE GaN are identified as possible point d efects. (C) 2001 American Institute of Physics.