A Static, Multisubstrate, In Silico Reactor Design of the MOCVD Process for Uniform Growth of GaN Epitaxial Layers

Abstract

Gallium nitride (GaN) epitaxial film properties depend critically on deposition uniformity and growth efficiency. While metal-organic chemical vapor deposition (MOCVD) is the dominant industrial technology, traditional vertical rotating disk reactors generate complex centrifugal fields, edge vortices, and gas short-circuiting. These flow instabilities degrade film purity, limit precursor utilization, and complicate process control, creating bottlenecks for large-scale, high-throughput integration. To address these limitations, a novel, rotation-free MOCVD reactor architecture designed for high-capacity batch scale-up is proposed. By eliminating the high-speed rotating susceptor (core moving component of traditional MOCVD) and adopting advanced structural flow control, the proposed static chamber accommodates six symmetrically arranged stationary substrates, which removes centrifugal flow disturbances induced by mechanical rotation. The system utilizes 12 independently distributed annular inlets to deliver trimethylgallium (TMGa) and ammonia (NH₃) isolated by inert carrier gases (H₂/N₂), successfully eliminating gas-phase prereactions at the source. Such units can be stacked up to increase throughput. Using an experimentally validated 3D multiphysics coupled model, the chamber height and exhaust outlet layout were optimized to suppress parasitic vortices. Numerical simulations demonstrate that the optimized design (75 mm chamber height) dramatically improves growth uniformity (GU) by 77.4% (from 0.04746 to 0.01074) compared to traditional rotating systems, while slightly increasing the average growth rate (GR) to 0.4774 μm/h. Furthermore, process parameter optimization (V/III ratio = 700, substrate temperature = 1373 K) enhances the growth rate to 0.509 μm/h while maintaining excellent uniformity. This rotation-free, multisubstrate design strategy offers a highly stable, low-complexity framework for next-generation, high-throughput semiconductor manufacturing equipment.