一种外延生长高质量GaN薄膜的新方法

采用化学方法腐蚀c-面蓝宝石衬底，以形成一定的图案；利用LP-MOCVD在经过表面处理的蓝宝石衬底上以及常规c-面蓝宝石衬底上外延生长GaN薄膜.采用高分辨率双晶X射线衍射(DCXRD)、三维视频光学显微镜(OM)、扫描电子显微镜(SEM)和原子力显微镜(AFM)进行分析，结果表明，在经过表面处理形成一定图案的蓝宝石衬底上外延生长的GaN薄膜明显优于在常规蓝宝石衬底上外延生长的GaN薄膜，其(0002)面上的XRD FWHM为208.80弧秒，(1012)面上的为320.76弧秒.同时，此方法也克服了传统 关键词： 表面处理 MOCVD 横向外延生长 GaN薄膜

A new method to grow high quality GaN film by MOCVD

Patterned c-plane sapphire substrate is prepared by chemical etching. GaN films are grown by LP-MOCVD on surface treated sapphire substrate and common c-plane sapphire substrate. The structure and properties of the GaN films are analyzed by high-resolution double crystal X-ray diffraction(DCXRD), scanning electron microscope(SEM) and atomic force microscope(AFM).The results indicate that the quality of GaN film grown on sapphire substrate prepared by surface treatment is superior to that grown on common c-plane sapphire substrate. High-resolution double crystal X-ray diffraction shows that for the GaN grown on surface treated sapphire substrate,the (0002) and (1012) reflections have full-width at half-maximum as low as 208.80arcsec and 320.76 acrsec, respectively. The shortcomings of procedure complexity and high crystallographic tilt in conventional lateral epitaxial overgrowth are overcome by using the new method.