Transport Phenomena in a Novel Large MOCVD Reactor for Epitaxial Growth of GaN Thin Films

In this paper, a novel super large metal organic chemical vapor deposition reactor used for epitaxial growth of gallium nitride (GaN) thin film is designed and characterized. In this novel design, three layers of circular slits located on the periphery of reactor are used as the inlets. The outlet is located at the center of the reactor. In this design, the converging effects of gas flow in the radial direction could counterbalance the depletion of metal organic source during the GaN deposition. Therefore, uniform film thickness could be obtained. Besides, the spray board with circular slits located between top and middle inlets is used to help obtain the uniform flow distribution and sharp temperature gradient. The numerical simulation results show that even if in so large reactor (with the diameter of bigger than 1 m) all the field distributions are in an acceptable range in low vacuum degree. Controllable trimethylgallium distribution could be obtained by changing of the flow velocity and mass fractions of various species.