【摘要】 用MOCVD技术在50mm蓝宝石衬底(0001)面上生长了GaN∶Mg外延膜,对样品进行热退火处理并作了Hall、双晶X射线衍射(DCXRD)和室温光致发光谱(PL)测试.Hall测试结果表明,950℃退火后空穴浓度达到 5×1017cm-3以上,电阻率降到2 5Ω·cm;(0002)面DCXRD测试发现样品退火前、后的半峰宽均约为 4′;室温 PL谱中发光峰位于2 85eV处,退火后峰的强度比退火前增强了8倍以上,表明样品中大量被H钝化的受主Mg原子在退火后被激活.更多还原

【Abstract】 Mg doped GaN epilayers are grown on 50mm basal plane sapphire substrates by metalorganic chemical vapor deposition.Thermal annealing treatments are carried out on the samples and Hall,double crystal X ray diffraction, and photoluminescence (PL) spectroscopy measurements are performed on the as grown and annealed samples,respectively.The Hall measurements show that after annealing at 950℃,the sample has a hole concentration of 5×10 17 cm -3 and a resistivity of 2 5Ω·cm.The X ray (0002) diffraction measurement shows that the as grown and annealed samples have the same full width at half maximum of 4arcmin.A dominant PL peak around 2 85eV is observed at room temperature PL spectra both on the as grown and the annealed samples,and the intensity of this PL peak of the annealed samples is eight times stronger than that of the as grown ones.It can be concluded that large numbers of Mg atoms passivated by H atoms in the as grown GaN epilayers are electrically activated by the annealing treatment.更多还原