A technique for manufacturing a semiconductor device includes the steps of preparing a stepped substrate made of a group III-V compound semiconductor and having a flat surface exposing a (1 0 0) plane and a slanted surface exposing an (n 1 1)B plane whrerein n is a real number of about 1.ltoreq.n,...http://www.google.de/patents/US5783845?utm_source=gb-gplus-sharePatent US5783845 - Semiconductor device and its manufacture utilizing crystal orientation dependence of impurity concentration 
