Growth of thick Al x Ga1− x N ternary alloy by hydride vapor-phase epitaxy

Abstract: Growth of thick Al x Ga1− x N ternary alloy using AlCl3 and GaCl gases as group III precursors was performed by hydride vapor-phase epitaxy (HVPE). C-axis-oriented AlGaN layers could be grown at 1100°C. It was found that the growth of Al x Ga1− x N by HVPE was affected by the presence of H2 in the carrier gas. Therefore, the solid composition x in Al x Ga1− x N ternary alloy could be controlled by changing the input Al mole ratio of the group III precursor (R Al) and/or the low range (<10%) of partial pressure of hydrogen (H2) in the carrier gas (F o). The growth rate of approximately 30μm/h was obtained under inert carrier gas (F o=0.0), while the growth rate decreased rapidly in the low R Al under a low partial pressure of H2 in the carrier gas (F o=0.1). These results are in good agreement with the thermodynamic prospect. Thus, the growth of Al x Ga1− x N using HVPE is thermodynamically controlled. [Copyright &y& Elsevier]