Improvement of crystalline quality of AlN and high-Al-content AlGaN at high growth rate using horizontal high-flow-rate MOVPE system

The influences of the growth temperature of the buffer layer and the growth rate of AlN at 1300 °C on AlN crystalline quality were investigated. By using a horizontal high-flow-rate metal organic vapor phase epitaxy reactor, the growth rate of AlN was increased linearly up to 18 μm/h with increasing trimethylaluminum input partial pressure in spite of the high growth temperature of 1300 °C; the full width at half maximum of the X-ray rocking curve of AlN was almost unchanged. Moreover, the Al
_0.5
Ga
_0.5
N layer was grown on AlN/sapphire and the atomic step was observed on the surface of AlN and AlGaN layers by atomic force microscopy.