Transient numerical study of temperature gradients during sublimation growth of SiC: Dependence on apparatus design

Abstract

Using transient and stationary mathematical heat transfer models including heat conduction, radiation, and radio frequency (RF) induction heating, we numerically investigate the time evolution of temperature gradients in axisymmetric growth apparatus during the sublimation growth of silicon carbide (SiC) bulk single crystals by physical vapor transport (PVT) (modified Lely method). Temperature gradients in the bulk and on the surface of the growing crystal can cause defects. Here, the evolution of these gradients is studied numerically during the heating, growth, and cooling stages, varying the apparatus design, namely the amount of the source powder charge as well as the size of the upper blind hole used for cooling of the seed. Our results show that a smaller upper blind hole can reduce the temperature gradients both in the bulk and on the surface of the crystal without reducing the surface temperature itself. r

Numerical Simulation of Temperature Fields in a Three-Dimensional SiC Crystal Growth Furnace with Axisymmetric and Spiral Coils

“…The weaker convection heat transfer is always ignored. For radiation heat transfer, species in the growth chamber are not participated in radiation process, so the surface to surface (S2S) radiation model is used to calculate radiation heat flux [2,[14][15][16]. The axisymmetric assumption is adopted in the majority of numerical simulation research, so the model is two-dimensional, the effect of non-axisymmetric coils on electromagnetic field and temperature field are always missed artificially.…”

Analysis of SiC crystal sublimation growth by fully coupled compressible multi-phase flow simulation

“…Many optimization procedures [4,13,24,25,29,30] for improving crystal quality have been suggested. In Refs.…”

“…In Ref. [30], a smaller upper blind hole for cooling of the seed was suggested to reduce the temperature gradients both in the bulk and on the surface of the crystal without reducing the surface temperature itself.…”

Increase of SiC sublimation growth rate by optimizing of powder packaging

“…Global heat and mass transport, growth kinetics, and thermal stresses and defect formation have been modeled [8][9][10][11][12][13][14][15][16]. Selder et al [9,12] developed a model to study the global heat and mass transfer in reactors and its dependence on various parameters and the influence on the crystal quality.…”

“…Selder et al [9,12] developed a model to study the global heat and mass transfer in reactors and its dependence on various parameters and the influence on the crystal quality. Geiser et al [13] developed a transient heat and mass transfer model to study temperature gradients during sublimation growth of SiC and its dependence on the apparatus design. In addition, vapor transport between powder charge and seed has been simulated [8][9][10][11].…”