On the reflection pattern made by a laser beam on the etched surface of germanium

A laser beam is shot on the surface of single-crystal germanium, after etching. From the reflection pattern, the characteristics of etched pits and hillocks are examined and it is found that etched pits not only are simple holes but also are convex. In addition, a new reflection pattern in the orientation of [110] is reported. These new data will be applied to decide the orientation of single-crystal growth and the effect of dislocation in crystal.