论文部分内容阅读
用X射线衍射方法通过不同晶面的ω扫描测试,分析了Si衬底GaN蓝光LED外延膜中n-型层δ掺杂Si处理对外延膜结晶性能的影响。报道了Si衬底GaN外延膜系列晶面的半峰全宽(FWHM)值。通过使用晶格旋转(Lattice-rotation)模型拟合,计算出样品的螺位错密度和刃位错密度。结果表明,δ掺杂Si处理后生长出的样品螺位错密度增大、刃位错密度减小,总位错密度有所减小。通过对未经δ掺杂处理和δ掺杂处理的GaN外延膜相应ω-2θ扫描半峰全宽值的比较,发现δ掺杂Si处理后生长出的样品非均匀应变较大;相应样品的LED电致发光光谱I、-V特性曲线显示δ掺杂后样品性能变好。
The influence of n-type δ-doped Si on the crystallization properties of epitaxial films was analyzed by X-ray diffraction (X-ray diffraction) on different scanning crystal planes. The full width at half maximum (FWHM) of GaN epitaxial films on Si substrate is reported. The screw dislocation density and the edge dislocation density of the sample were calculated by using the Lattice-rotation model fitting. The results show that the dislocation densities of the samples grown after δ-doped Si treatment increase, the dislocation density of the edge decreases and the total dislocation density decreases. By comparing the full width at half maximum of the corresponding ω-2θ scan of GaN epitaxial films without δ-doping and δ-doping, it was found that the non-uniform strain of the samples grown after the δ-doping Si treatment was large. LED electroluminescence spectrum I, -V characteristic curve shows that the δ-doped samples better performance.