Crack-free growth of UVC LEDs on 6-inch sapphire substrates using face-to-face high-temperature annealed AlN by production scale MOCVD

In this study, growth of crack-free AlGaN-based UVC LEDs using face-to-face high-temperature annealed AlN templates on 6-inch sapphire substrates was investigated by production scale metal-organic chemical vapor deposition (MOCVD). The utilization of face-to-face annealed sputtered-deposited thin AlN films templates successfully mitigated wafer bowing, leading to crack-free growth. Additionally, single-peak UVC emissions were obtained in the growth of 6-inch x 7-wafers, and the in-plane uniformity of (Max - Min) / Average was approximately 1.6%. Face-to-face high-temperature annealed AlN proves to be suitable for growing large-diameter UVC LEDs wafers, paving the way for mass production.