Growth of AlxGa1−xN epitaxial thin film on sapphire substrate by plasma assisted metal organic chemical vapor deposition (PA-MOCVD)

This paper reported the study of growth of Al_xGa_1-xN thin film on a-plane sapphire substrate using plasma assisted metal organic chemical vapor deposition (PA-MOCVD). We have successfully growth the Al content AlGaN alloys and investigated the influence of TMA/TMAl+TMGa flow rate ratio to their crystal structure and surface morphology. From S EM image and XRD measurement, the AlGaN films grown with TMA/TMAl+TMGa flow rate ratio of 20% have single crystal orientation, homogeneous and smoother surface morphology. From ED X microanalysis results, all of the AlGaN alloys have high Al content. The Al content of the AlGaN alloys with TMA/TMAl+TMGa flow rate ratio of 20%, 30%, and 40% is about x = 0.5, 0.6, and 0.65, respectively and grown at the growth temperature about of 700°C.