Epitaxial growth of AlN films on Si (111)

Abstract

Plasma assisted molecular beam epitaxial growth of AlN on Si(111) at various substrate temperatures with the same III‐V ratio is investigated. The epitaxial structures were characterized by high resolution X‐ray diffraction (HR‐XRD), scanning electrical microscopy (SEM) and atomic force microscopy (AFM). With the increase of the growth temperature, the full‐width at half‐maximum (FWHM) of the AlN (0002) reflection peak in HR‐XRD rocking curve measurements decreases from 5898.5 arcsec for films grown at 575 °C to 1784.9 arcsec for films grown at 900 °C, respectively. AFM images show that the surface roughness decreases with increasing growth temperatures. Though the AlN films are grown with same III/V ratio, the AlN films grown at 575 °C shows nitrogen rich feature and the ones grown at higher temperatures show the metal rich features. The presence of the film morphology can be explained by al mobility.