论文部分内容阅读
激光剥离(LLO)技术是研制新型氮化镓(GaN)基谐振腔结构光电子器件的关键技术。然而LLO后的GaN表面往往具有较大的粗糙度,而制作谐振腔结构器件需要很高的表面平整度,因此需要对LLO后的GaN表面进行抛光。分别采用金刚石粉抛光液和胶粒二氧化硅抛光液进行机械抛光和化学机械抛光(CMP),并对比了两种方法获得的抛光结果,研究发现前者会在抛光后的GaN表面引入划痕,而采用后者可以得到亚纳米级平整度的表面。进一步的实验结果表明,胶粒二氧化硅抛光液同样适用于图形化衬底外延片激光剥离后的GaN表面抛光。
Laser lift-off (LLO) is a key technology in the development of new gallium nitride (GaN) based resonator optoelectronic devices. However, the GaN surface after LLO tends to have a large roughness, and the resonator structure device needs high surface flatness, so the GaN surface after LLO needs to be polished. The mechanical polishing and chemical mechanical polishing (CMP) were carried out by using diamond powder slurry and colloidal silica slurry, respectively. The results of the two methods were compared. It was found that the former would introduce scratches on the polished GaN surface, The latter can be sub-nanometer surface smoothness. Further experimental results show that the colloidal silica slurry is also suitable for polishing GaN surface after laser stripping of patterned substrate epitaxial wafers.