Ultrahigh Vacuum, Chemical Vapor Deposition
Application ID: 21711
Chemical vapor deposition (CVD) is a process often used in the semiconductor industry to grow layers of high-purity solid material on top of a wafer substrate. CVD is achieved using many different techniques and across a range of pressures from atmospheric to ultrahigh vacuum (UHV/CVD).
UHV/CVD is performed at pressures below 10-6 Pa (10-8 Torr), so gas transport is achieved by molecular flow and lacks any hydrodynamic effects such as boundary layers. In addition, there is also no gas-phase chemistry involved due to the low frequency of molecular collisions, so growth rate will be determined by the number density of species and surface molecular decomposition processes.
This model uses multiple species, free molecular flow to model the growth of silicon wafers. The effect from several pumping curves are explored.
This model example illustrates applications of this type that would nominally be built using the following products:
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 Grille des Spécifications 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.