Growth optimization during III-nitride multiwafer MOVPE using real-time curvature, reflectance and true temperature measurements

We employed a newly developed wafer-selective curvature, reflectance and temperature sensor (EpiCurveTT®) in an AIX2600HT Planetary Reactor®. Growth of GaN on sapphire as well as AlGaN and InGaN heterostructures with different material compositions were monitored in real time. During growth of a laser-diode text structure the impact of water curvature on wavelength uniformity across the water is demonstrated. Here, the known drastic dependence of indium incorporation on growth temperature requires a uniform substrate surface temperature and therefore a flat wafer during growth of the MQW region. Wafer bowing depending on substrate properties, growth temperature and the insertion of a strain-compensating interlayer is carefully examined to optimize the growth procedure.