超高能量电子辐照氮掺杂金刚石的光致发光研究

Photoluminescence Studies on Nitrogen-Doped Diamond after Ultra High Energy Electron Irradiation

利用低温光致发光光谱研究了MeV超高能量电子辐照氮掺杂金刚石,结果表明,辐照缺陷以氮-空位缺陷(NV)和中性单空位缺陷(GR1)为主;辐照电子经1.2 mm铝箔遮挡后,其能量大幅度衰减,金刚石中只剩余了NV缺陷,这表明此时辐照产生的空位都被氮杂质所束缚而以NV缺陷形式存在;经800℃高温退火后,空位扩散到晶体表面以下约15μm处而被氮杂质束缚,进而使得GR1信号减弱而NV信号增强。

The low-temperature photoluminescence spectroscopy was employed to characterize the nitrogen-doped diamonds after ultra-high energy electron irradiation. The results show that the irradiated defects are mainly nitrogen-vacancy(NV) and neutral single vacancy defects(GR1);after being blocked by 1.2 mm aluminum foil, the irradiation energy is greatly attenuated, and only NV defects remain in diamond. These indicates that the vacancies generated by irradiation are trapped by nitrogen impurities and transferred in the form of NV defects, after high temperature annealing of 800 ℃, the vacancies diffuse from surface towards inner about 15 μm of the crystal, and then is trapped by nitrogen impurities which leads into the decrease of GR1 center while the enhancement of NV center.