Growth of GaN on porous SiC by molecular beam epitaxy

One of the major hurdles in the epitaxial growth of high quality GaN thin films is the unavailability suitable substrates. The lack of suitable substrates leads to poor quality epitaxial films with dislocation densities in the range of 1010-1012 cm-2 for GaN grown on sapphire [1] [2] and SiC [3]. Such high defect densities are detrimental to the device performance; conventional III-V (like GaAs) devices have defect densities about 4 orders of magnitude lower than presently achievable in GaN.