Hydride vapor phase epitaxy of InN by the formation of InCl3 using In metal and Cl2

Hydride vapor phase epitaxy (HVPE) of InN using In metal, Cl2 and NH3 as source materials and N2 carrier gas was investigated on sapphire (0 0 0 1) substrates. A thermodynamic analysis of the reaction between In metal and Cl2 gas in the source zone of the HVPE system revealed that the equilibrium partial pressure of InCl3 increased significantly with decreasing source zone temperature, while that of InCl remained almost constant. At a substrate temperature of 500 °C, appreciable growth of InN occurred by decreasing the source zone temperature to 450 °C. This means that InN growth occurs by the reaction between InCl3 and NH3. With an optimum surface nitridation time of the sapphire substrate prior to InN growth, c-axis oriented single-crystalline layers of InN were obtained. Cathodoluminescence (CL) spectrum measured at room temperature showed a strong peak at 0.75 eV.