Abstract
The chemical etching characteristics of 
are studied through an
mask in the solutions of various etching systems: (i) 
, (ii) 
, (iii) 
, (iv) 
, and (v) 
. The etched depth is evaluated by using a calibrated optical microscope. The etching profiles are examined by cleaving the wafer in orthogonal directions along the (110) and (
10) planes. Various etching profiles, such as V‐shaped, reverse mesashaped ones, and nearly vertical walls, are formed by stripes being etched on the (001) planes. The indexes of the etch‐revealed planes are identified by making a comparison with the calculated angle between the (001) surface and etch‐side plane. The utility of these etching solutions is also discussed for a variety of 
device applications.