Chemical Vapor Deposition of GaAs
Application ID: 945
Chemical vapor deposition (CVD) allows a thin film to be grown on a substrate through molecules and molecular fragments adsorbing and reacting on a surface. This example illustrates the modeling of such a CVD reactor where triethyl-gallium first decomposes, and the reaction products along with arsine (AsH3) adsorb and react on a substrate to form GaAs layers.
The CVD system is modeled using momentum, energy, and mass balances including a detailed description of the gas phase and adsorption kinetics. A reduced reaction scheme is compared to the full scheme in the Reaction Engineering interface.
The model highlights the usability of the Reaction Engineering and Chemistry interfaces together with the Reversible Reaction Group feature for simulation of reaction/transport systems in 0 D and space-dependent reactors. In the Reaction Engineering interface you can easily study the transient behavior of different sets of reactions in a perfectly mixed system. The Chemistry interface collects reaction kinetics and calculates transport and thermal parameters, which can seamlessly be coupled with other interfaces.
In this application, you also utilize the Reversible Reaction Group feature for CHEMKIN import and organization of the complex system of bulk and surface reactions that are involved in the CVD process. The space-dependent model accounts for mass transport, heat transfer and fluid flow in the CVD reactor using the Transport of Diluted Species, Heat Transfer in Fluids, and Laminar Flow interfaces.
This model example illustrates applications of this type that would nominally be built using the following products:Chemical Reaction Engineering Module
however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
The combination of COMSOL® products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries. Particular functionality may be common to several products. To determine the right combination of products for your modeling needs, review the Specification Chart and make use of a free evaluation license. The COMSOL Sales and Support teams are available for answering any questions you may have regarding this.