Mechanical, Thermal and Flow Dynamics Issues in Compound Semiconductor MOCVD Reactor Design

Abstract

In recent years Metalorganic Chemical Vapor Deposition (MOCVD) becomes a key epitaxial process for a variety of compound semiconductor devices such as: GaAs/AlGaAs lasers, HEMTs, LEDs, photocathodes, solar cells, and MESFETs; InP/InGaAsP long wavelength lasers and detectors; InP/InGaAs quantum wells and detectors, etc. Development of reliable, high throughput equipment is a major task in the implementation of MOCVD into cost-effective manufacturings. We have used Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) software to model thermal, structural, and flow processes for the scaling of EMCORE vertical, high speed rotating disk reactor (RDR) to large dimensions (four 4″ wafers located on 12″ wafer carrier). Flow modeling was used to determine basic reactor geometry and the relation between process parameters such as total reactant flow, temperature, pressure, and rotation speed. Thermal and structural analysis was used to produce a uniform substrate temperature, avoid reactor overheating and decrease thermal stress. Flow and temperature distribution predicted by the modeling were found to be well correlated with experimental results.