Method for forming a low-defect epitaxial layer in the fabrication of semiconductor devices

摘要

In semiconductor devices such as laser diodes (LD) and light emitting diodes (LED) based on gallium nitride thin films, low defect density is desired in the gallium nitride film. In the fabrication of such devices on a silicon carbide substrate surface, the gallium nitride film is formed on the silicon carbide substrate after the substrate surface is etched using hydrogen at an elevated temperature. In another embodiment, an aluminum nitride film is formed as a buffer layer between the gallium nitride film and the silicon carbide substrate, and, prior to aluminum nitride formation, the substrate surface is etched using hydrogen at an elevated temperature.