Growth of thick AlGaN by mixed-source hydride vapor phase epitaxy

Growth of a thick AlGaN layer on GaN/Al2O3 substrate is performed by mixed-source hydride vapor phase epitaxy (HVPE) method. The AlGaN material is compounded from chemical reaction between a NH3 and an aluminum-gallium chloride formed by HCl which is flown over metallic Ga mixed with Al. The AlGaN epitaxial layer is analyzed by Auger-electron spectroscopy (AES) and X-ray diffraction (XRD) measurement to characterize the AlGaN. Al concentration is estimated to be in the range of 0.5–6%. We suggest that the metallic Ga mixed with Al can be used as a group III source material in the HVPE growth of the AlGaN layer.