CdGeAs_2晶体的蚀坑形貌观察

采用金相显微镜和扫描电镜观察了垂直布里奇曼法生长的新型红外非线性光学晶体砷锗镉(CdGeAs2)单晶片(101)面蚀坑形貌。选择机械研磨、物理抛光及质量分数为3%溴甲醇在室温下对晶片化学抛光1min左右的工艺,获得了表面平整无划痕的CdGeAs2晶片。报道了一种新的CGA晶体择优腐蚀剂,其组成为HCl∶HNO3∶H2O=1∶1∶1(体积比),室温下腐蚀晶片30s左右后在金相显微镜和扫描电镜下观察到CdGeAs2晶体(101)晶面的腐蚀坑,蚀坑形貌呈取向一致的等腰三角形,边界清晰,具有立体感,并从理论上分析讨论了(101)面三角形蚀坑的形成原因。

Observation of Etching Morphology of CdGeAs_2 Crystal

The etch pits morphology of germanium cadmium arsenide (CdGeAs2) crystal grown using vertical Bridgman method was observed by metallographic microscope and scanning electron microscope (SEM). By mechanical grinding, physical polishing, with the non-preferential etchant 3%(mass fraction) bromine methanol(BM) solution to polish the CdGeAs_2 crystal wafer about 1min, a smooth surface without scratching was obtained. A preferential etchant HCl∶HNO_3∶H_2O=1∶1∶1(volume ratio) for CGA crystal was studied. It can be used to produce well-defined etch pits morphology of (101) face at room temperature after chemical polishing. The triangular shape of etch pits with clear and consistent orientation was observed in the optical microscope and scanning electron microscope, and the reasons for formation of triangular shape of etch pits on (101) face were also analyzed in theory.