Models of processes underlying the metalorganic chemical vapor deposition (MOCVD) of binary and ternary III-V semiconductors

Models of transport phenomena and chemical reactions underlying the metalorganic chemical vapor deposition (MOCVD) of binary and ternary semiconductors in horizontal reactors have been developed. The main focus has been to investigate the growth characteristics of the ternary semiconductor {dollar}rm Alsb{lcub}x{rcub}Gasb{lcub}1-x{rcub}As{dollar} (0 {dollar}le{dollar} x {dollar}le{dollar} 1) and optimize the thickness and compositional uniformity of the films grown in horizontal reactors. Other topics investigated include fluid dynamics in MOCVD reactors and design of computational algorithm for distributed computing environment.; The transient convection-diffusion studies for a single reactant diluted in a carrier gas, demonstrate the trapping of precursors in the buoyancy driven recirculation cells when the reactor is sought to be purged of the reactants. This phenomenon of delay in purging of the reactants can result in diffuse heterojunctions of low quality. It has been demonstrated in this study that a unidirectional flow in the force convection dominated regime resulting from high inlet velocities or low operating pressures can help alleviate the problem of transverse recirculation cells and trapped material. Since operating the reactor at very high velocities results in wastage of expensive precursors, conditions under which the transverse recirculations are just eliminated have been identified for a typical horizontal reactor. The following criteria have been identified from simulations, for the onset of transverse recirculations: {dollar}{dollar}rm (Gr/Re)<100 for 10sp{lcub}-3{rcub}