DEFECT REDUCTION IN SEMICONDUCTOR MATERIALS

摘要

An initial epitaxial layer (2) of GaN is grown on a sapphire substrate (2). The epitaxial layer (2) is then etched in a reactive ion etch (RIE) chamber. This etching acts preferentially at defects (3), causing them to become enlarged cavities (5). The cavities (5) are too large in proportion to the crystal lattice to act as defects in the usual sense, and so a further GaN epitaxial layer fills into the cavities. Thus, propagation of defects is avoided.