High quality thin AlN epilayers grown on Si(110) substrates by metal-organic chemical vapor deposition

Thin AlN epilayers are grown on Si(110) by metal-organic chemical vapor deposition, and are intentionally treated not only as conventional seed layers but also as base layers for high quality AlGaN epilayer growth. By controlling the growth conditions, a V-shape pit free AlN surface with atomic steps is achieved. Characterization results of high resolution X-ray diffraction show that the structural qualities of the thin AlN epilayers grown on Si(110) are excellent, and the epilayers are superior to those grown on Si(111) with the same thickness in the literature. In addition, the structural quality of the AlGaN epilayers grown on AlN/Si(110) is confirmed to strongly depend on the underlying AlN epilayer. Furthermore, it is important to control the AlN thickness to prevent the generation of large cracks during the growth process. Our results present potential applications of high quality III-nitrides grown on Si(110) for optical (UV region) and power device applications.