X射线分析氢化物汽相外延法生长GaN薄膜(英文)

X-ray Analysis of GaN Film Grown by Hydride Vapor Phase Epitaxy

氮化物研究在 90年代取得显著进步 ,成功制造出蓝色发光二极管和激光二极管。由于氮化镓与衬底(如 :蓝宝石 ,碳花硅 )间存在大的晶格常数和热膨胀系数失配 ,外延膜中有非常高的位错密度。研究氢化物汽相外延法生长的氮化镓膜中倾斜和扭转现象 ,并应用到以X射线摇摆曲线的半峰宽计算氮化镓膜中位错密度。Φ扫描曲线表征外延的氮化镓晶体六方对称性 ,而极图表明氮化镓膜中存在马赛克结构。计算出螺位错密度为 :2 93× 1 0 9cm-2 和刃位错密度为 :5 2 5× 1 0 10 cm-2 。

The tilting and twisting in the GaN film grown by HVPE method were investigated and used to c alculate the dislocation density with FWHM value of the XRD rocking curve. The Φ scan curve shows the hexagonal symmetry of the GaN film, and the polar picture presents the mosaic structure in the GaN film. The screw threading dislocation d ensity is 2 93×10 9cm -2 and the edge threading dislocation density is 5 25×10 10cm -2.