Observation of Etch Pits Morphology on the (112) Face of AgGa_(0.8)In_(0.2)Se_2 Crystal
WANG Ying,ZHU Shi-fu,ZHAO Bei-jun,CHEN Bao-jun,HE Zhi-yu,WAN Shu-quan,LONG Yong (Department of Materials Science,Sichuan University,Chengdu 610064,China)
A new etchant was studied out for preferential etching the (112) face of AgGa0.8In0.2Se2 crystal at room temperature and a new etching technique was presented. AgGa0.8In0.2Se2 crystal was grown by improved Bridgman method and directively cut out the wafer of (112) face from the crystal. Then,the wafer was grinded,mechanically polished,and etched in the etching solution of HNO3(65%-68%)∶HCl(35%-38%)=1∶2.5 (volume ratio) for 5 min at room temperature with ultrasonic vibration. The etching pits were clearly observed under the metalloscope. The shape of the etch pits of the (112) face appeared approximately to equilateral triangle. The formation cause of etch pits and the shape on the (112) face were theoretically analyzed.