High-speed and long-time growth of GaN by suppressing gas-phase reaction in the oxide vapor phase epitaxy method

Abstract In the growth of GaN using the oxide vapor phase epitaxy method, the issue of polycrystallization was likely to occur during high-speed growth owing to the high reactivity of Ga 2 O and NH 3 . Previous studies have shown that polycrystallization can be reduced by suppressing the gas-phase reactions. Recent thermodynamic analysis has predicted that gas-phase reactions can be further suppressed while maintaining high growth rates in the low V/III ratio region with a high Ga 2 O flow rate and a low NH 3 flow rate. In this study, we performed crystal growth in the predicted region and verified the suppression of gas-phase reactions. Under conventional conditions, polycrystallization occurred when grown for a long time at a growth rate of 200 μm h −1 , but by applying growth conditions close to the predicted region, polycrystallization during long-time growth was suppressed, and a 1 mm thick GaN crystal was obtained.