Fabrication of Abrupt AlN/GaN Multi Quantum Wells by Low Temperature Metal Organic Vapor Phase Epitaxy

AlN/GaN multi quantum wells (MQWs) with abrupt interface were grown by metal organic vapor phase epitaxy (MOVPE). It was revealed that the interface abruptness and coherency of AlN/GaN MQWs to AlN buffer layer were improved at lower temperature of 930 °C. We suggest that the inter-diffusion between wells and barriers was suppressed by lowering growth temperature. The surface of MQWs became smooth at lower temperature of 930 °C showing 0.86 nm of root mean square (RMS) value. Therefore, it is strongly suggested that the low temperature growth at 930 °C is essential for the fabrication of abrupt and smooth AlN/GaN MQWs by MOVPE.