Method for engraving gallium nitride layer with hexagonal crystalline structure directed along crystalline plane for manufacturing mesa-type Schottky diode, involves eliminating cylindrical protuberances by wet-engraving

摘要

The method involves thinning a gallium nitride layer (3) by dry-engraving in conditions adapted to assure occurrence of flatness defects in a form of cylindrical protuberances (33) related to a presence of dislocations (21) and nanotubes (23), and to avoid the occurrence of flatness defects in a form of hollow cavities related to the presence of dislocations. The protuberances are eliminated by wet-engraving using phosphoric acid based solution. The gallium nitride layer is assembled on a support (7) containing silicon oxide.