摘要
Nonpolar （1150） a-plane GaN films are grown by metal-organic chemical vapour deposition （MOCVD） on r-plane （1102） sapphire. The samples are irradiated with neutrons under a dose of 1× 1015 cm-2. The surface morphology, the crystal defects and the optical properties of the samples before and after irradiation are analysed using atomic force microscopy （AFM）, high resolution X-ray diffraction （HRXRD） and photoluminescence （PL）. The AFM result shows deteriorated sample surface after the irradiation. Careful fitting of the XRD rocking curve is carried out to obtain the Lorentzian weight fraction. Broadening due to Lorentzian type is more obvious in the as-grown sample compared with that of the irradiated sample, indicating that more point defects appear in the irradiated sample. The variations of line width and intensity of the PL band edge emission peak are consistent with the XRD results. The activation energy decreases from 82.5 meV to 29.9 meV after irradiation by neutron.
Nonpolar （1150） a-plane GaN films are grown by metal-organic chemical vapour deposition （MOCVD） on r-plane （1102） sapphire. The samples are irradiated with neutrons under a dose of 1× 1015 cm-2. The surface morphology, the crystal defects and the optical properties of the samples before and after irradiation are analysed using atomic force microscopy （AFM）, high resolution X-ray diffraction （HRXRD） and photoluminescence （PL）. The AFM result shows deteriorated sample surface after the irradiation. Careful fitting of the XRD rocking curve is carried out to obtain the Lorentzian weight fraction. Broadening due to Lorentzian type is more obvious in the as-grown sample compared with that of the irradiated sample, indicating that more point defects appear in the irradiated sample. The variations of line width and intensity of the PL band edge emission peak are consistent with the XRD results. The activation energy decreases from 82.5 meV to 29.9 meV after irradiation by neutron.
作者
许晟瑞
张金风
谷文萍
郝跃
张进成
周小伟
林志宇
毛维
Xu Sheng-Rui;Zhang Jin-Feng;Gu Wen-Ping;Hao Yue;Zhang Jin-Cheng;Zhou Xiao-Wei;Lin Zhi-Yu;Mao Wei(National Key Laboratory of Fundamental Science for Wide Band-Gap Semiconductor Technology,School of Microelectronics,Xidian University,Xi'an 710071,China)
基金
supported by the National Key Science and Technology Special Project,China (Grant No.2008ZX01002-002)
the Major Program and State Key Program of the National Natural Science Foundation of China (Grant Nos.60890191 and 60736033)
the Fundamental Research Funds for the Central Universities,China (Grant No.JY10000904009)
