C注入GaN光致发光和微区拉曼散射的研究

A study of photoluminescence and micro-Raman scattering in C-implanted GaN

使用光致发光谱和微区拉曼散射谱的测量,研究了C离子注入原生无黄光发射的GaN。C离子的注入剂量范围为1013-1017cm-2。发光谱的研究表明,C注入的GaN经950℃高温退火后出现了黄光发射,而近带边发射峰的峰位则由于C注入产生的某种缺陷而发生了蓝移。拉曼谱的测量表明,GaN薄膜的应力不随C注入而改变。当注入剂量增加至1015cm-2时,出现了与无序激活拉曼散射相关的300cm-1峰,但随着注入剂量进一步增加,300cm-1峰减弱并未消失,这被归因于注入束流强度随注入剂量增大。

GaN samples （no yellow luminescence） in their as-grown states were implanted with 10^13-10^17 C ions/cm^2 and studied by photoluminescence spectra and micro-Raman scattering spectra. The photoluminescence study showed that yellow luminescences were produced in the C-implanted GaN after 950℃ annealing, and the peaks of the near band edge emissions showed blue-shifts after C implantation. The Raman measurements indicated that the stresses in GaN films did not change after C implantation. The samples implanted with 10^15 cm^-2 carbon ions had the Raman peak at 300 cm^-1, which is associated to the disorder-activated Raman scattering. However, further increasing the implantation dose resulted decreased intensity of the 300 cm^-1 peak, due to the ion beam current increase with the implantation dose.