PENDEOEPITAXIAL GROWTH OF GALLIUM NITRIDE LAYERS ON SAPPHIRE SUBSTRATES

摘要

Gallium nitride semiconductor layers may be fabricated by etching anunderlying gallium nitride layer (104) on asapphire substrate (102a), to define at least one post (106) in the underlyinggallium nitride layer and at least one trench (107) in theunderlying gallium nitride layer. The at least one post includes a galliumnitride top and a gallium nitride sidewall (105). The at leastone trench includes a trench floor. The gallium nitride sidewalls arelaterally grown into the at least one trench, to thereby form agallium nitride semiconductor layer. In a preferred embodiment, the at leastone trench extends into the sapphire substrate such thatthe at least one post further includes a sapphire sidewall an a sapphirefloor. A mask (201) may be included on the sapphire floorand an alluminum nitride buffer layer (102b) also may be included between thesapphire substrate and the underlying gallium nitridelayer. A mask (209) also may be included on the gallium nitride top. The maskon the floor and the mask on the top preferablycomprise same material.