Parametric analysis of control parameters in MOCVD

Abstract This paper deals with the identification and the analysis of the critical control parameters in the MOCVD growth process. The MOCVD growth process is relatively independent of susceptor temperature, but is extremely sensitive to the composition of the reactive gas stream immediately above the susceptor. Control of the composition of the gas stream in the reaction chamber implies control of composition in the source gas manifold. A rigorous analysis of the control of gas flows and composition has been made for standard plumbing design layouts. The relative change in growth rate and composition of the final layer has been determined as a function of setpoint drift of: the mass flow controllers, the bubbler temperatures, and system pressure. Using the derived functions, comparisons have been made between various gas manifold designs showing their strengths and often subtle potential pitfalls.