Real-time optical monitoring of gas phase dynamics for the growth of InN at elevated pressures

Abstract

ABSTRACTThe request for increased performance in high-power / high-frequency optoelectronic devices requires new methods for the fabrication of high quality III nitride alloys that exhibit large thermal decomposition pressure such as InN and related materials. To extend the process and growth window towards elevated pressures, a high-pressure CVD system with integrated real time optical characterization techniques has been constructed. The built-in real-time monitoring techniques allow the characterization of gas flow dynamics, precursor decomposition kinetics, as well as the monitoring of the crucial steps of nucleation and film formation. The gas flow dynamics has been characterized and the process parameter are obtained under which the thin film growth process can be maintained under laminar flow condition. Laser light scattering (LLS) has been proven as the most robust optical tool to characterize the onset of turbulence.