上海科技大学知识管理系统

The unintentional Fe incorporation in the homo-epitaxy of GaN on Fe-doped freestanding GaN substrate is harmful to the performance of HEMT device, but the incorporation mechanism is unclear. The memory effect, diffusion from the Fe-doped GaN substrate to the epilayer, thermal decomposition on the N-face and Ga-face are all considered to find the origin. The Ga-face thermal decomposition during the heating process before growth is regarded as the main reason responsible for the unintentional Fe doping according to the TOF-SIMS, VPD-ICPMS, and D-SIMS measurement results. MBE growth of GaN epilayer at lower temperature could effectively suppress the unintentional Fe doping.The unintentional Fe incorporation in the homo-epitaxy of GaN on Fe-doped freestanding GaN substrate is harmful to the performance of HEMT device, but the incorporation mechanism is unclear. The memory effect, diffusion from the Fe-doped GaN substrate to the epilayer, thermal decomposition on the N-face and Ga-face are all considered to find the origin. The Ga-face thermal decomposition during the heating process before growth is regarded as the main reason responsible for the unintentional Fe doping according to the TOF-SIMS, VPD-ICPMS, and D-SIMS measurement results. MBE growth of GaN epilayer at lower temperature could effectively suppress the unintentional Fe doping.