WAFER SEPARATION TECHNIQUE FOR THE FABRICATION OF FREE-STANDING (AL, IN, GA)N WAFERS

摘要

A method of fabricating free-standing (Al, In, Ga)N substrates, by in situ separation of thick epitaxially grown nitride films from their foreign substrates. A suitable substrate for (Al, In, Ga)N film growth is selected, and foreign ions are implanted in the substrate to form a comparatively sharp concentration profile. An (Al, In Ga)N film is deposited on the substrate, and the deposited film is cooled to introduce thermal expansion mismatch-related strain, so that the film spontaneously separates from the substrate.