论文部分内容阅读
通过改变MOCVD生长GaN反应的V/III比来改变横/纵向生长速度比,以此来研究两步法中高温GaN层的横向生长对材料结构性质的影响.透射电子显微镜(TEM)和X射线衍射(XRD)实验的研究表明,高温GaN层的横向生长速度越快,位错的传播方向更易于偏离c轴,弯向晶粒内部,且弯曲的位置越靠近缓冲层,但位错密度并不随横向生长的加速而单调变化.提出了一个关于GaN生长动力学过程和位错弯曲机制的模型以解释横向生长与GaN结构的对应关系.
The effect of lateral growth of high-temperature GaN layer on the structure properties of the materials was investigated by changing the ratio of V / III growth rate by V / III ratio of MOCVD growth to GaN reaction.Transmission electron microscopy (TEM) and X-ray Diffraction (XRD) experiments show that the higher the lateral growth rate of high-temperature GaN layer, the more the dislocation propagation direction deviates from the c-axis and is bent to the inside of the grain, and the closer the bending position is to the buffer layer, Does not change monotonically with the acceleration of lateral growth.A model is proposed for the growth kinetics of GaN and the mechanism of dislocation bending to explain the correspondence between lateral growth and GaN structure.