Hydride Epitaxial GaN Simulator HEpiGaNS

HEpiGaNS (Hydride Epitaxial GaN Simulator) is designed for modeling of GaN crystal growth by hydride vapor phase epitaxy (HVPE).

Fig 1. Combined triangular and quadrilateral computational mesh in the growth domain.

Global Heat Transfer Problem in a HVPE Reactor for GaN Crystal Growth

• Inductive heating. The computation of the Joule heat sources due to inductive heating is carried out by solving the Maxwell equations
• Conductive heat transfer in solid materials. The thermal conductivity of the materials used in the growth system can be prescribed by the user as a function of temperature. Anisotropic thermal conductivity can be assigned
• Convective and radiative heat transfer in transparent gas blocks. The effect of convection on temperature distribution in the whole reactor is taken into account. The view-factor technique is used to model the radiation heat exchange

Fig. 2. Species mass fraction distributions near the wafer.

Species Transport in the Reactor

• Non-isothermal flow of gas mixture
• Multi-component diffusion of reactive species, including GaCl, HCl, NH₃, N₂, and H₂

Heterogeneous Chemical Processes

• Chemically reactive surfaces of the GaN crystal
• Chemically reactive surfaces of reactor side walls where GaN deposit is formed
• Chemically reactive surfaces of the boat with liquid Ga
• A quasi-thermodynamic model is used to describe the mass exchange between the vapor and solid surface
• Crystal evolution during the growth within the quasi-stationary approximation
• Polycrystalline deposit evolution on the reactor walls

Crystal Characterization

• Computation of the thermal stress distribution in the crystal, including the density of gliding dislocations in the crystal calculated on the assumption of a full stress relaxation due to plastic deformation. This option is available for axisymmetric vertical reactors, providing an adequate simulation of the growth of hexagonal crystals on (0001) face
• Analysis of the propagation of threading dislocations in the growing GaN crystal on a SiC or sapphire substrate

Fig 3. Modeling of the crystal and deposit shape evolution. t = 10 h.

Supply Configurations
HEpiGaNS is supplied in the following configurations:

• Heat Transfer
• Steady State Mass Transport
• Basic Configuration (Long Term Growth)

Support
Hot-line support is provided on request. The support includes free of charge supply of updated versions released during the license period and technical consulting on the HEpiGaNS™ operation.

More Information
More detailed information about the HEpiGaNS can be requested by the e-mail address hepigans-support@semitech.us

Fig 4. Species mass fraction distributions near the boat.