Simple and Accurate Prediction of AlGaN Metal-Organic Vapor Phase Epitaxy Growth

Modeling of metal-organic vapor phase epitaxy (MOVPE) is very complex, with many effects of temperature, hydrodynamics, thermodynamics, and kinetics needing to be taken into account. However, in this study, the growth behavior of AlGaN growth for high electron mobility transistors (HEMTs) is predicted using a simple model of parasitic gas phase reactions between tri-methyl aluminium (TMAl) and NH3, while taking into consideration desorption of AlGaN during growth with Arrhenius behavior. This leads to an average difference between predicted and measured values of around 1% for both thickness and composition calculations, which is very accurate considering the wide range of conditions used. This opens the way for simple predictions for AlGaN growth using a close-coupled showerhead reactor within a defined process window.