Influence of the TMAl source flow rate of the high temperature AlN buffer on the properties of GaN grown on Si(111) substrate

By optimizing TMAl source flow rate of high temperature AlN buffer layers, we were able to obtain a 1-μm-thick crack-free GaN layer, the (0002) and (101¯2) XRD FWHM of the GaN film are 547 and 563 arcsec respectively, the tensile stress calculated from the Raman spectra is 0.4 GPa.114