Increase of SiC sublimation growth rate by optimizing of powder packaging

The behavior of powder sublimation in the long-term PVT growth of SiC crystals

“…However, v 0 (0.767 mm/h) is less than v (0.809 mm/h) in simulation c. On the one hand, the rate of powder sublimation is larger than the mass transportation rate between the powder and the seed and it makes the SiC vapor gradually accumulate above the disk and then the pressure of the SiC vapor above the disk becomes so large that the channels of mass transportation in the powder are obstructed seriously. One the other hand, the large temperature gradient in the powder will induce the growth of the crystal granule in the low temperature gradient zone [3], and then, the permeability of the powder decreases if the particle diameter of the SiC powder increases [7]. Low permeability of the powder not only decreases the sublimed powder mass but also increases the SiC vapor pressure in the low temperature gradient zone of the powder.…”

“…SiC powder is used as the source material, in which physical and chemical processes occur during the long-term growth. In the last few years experimental study of the powder density during growth by X-ray technique demonstrated the formation of a dense disk and compressed core as well as the graphitization of the SiC granules [1][2][3][4][5][6][7]. Numerical modeling is a powerful tool to study the powder evolution.…”

Advanced Model of Silicon Carbide Based Uranium Ceramic Nuclear Fuel Production

“…The model equations are solved using the finite difference method [11,23]. The computational code is modified from an original code for simulating cigarette smoldering process [12].…”

Thermodynamic analysis of SiC polytype growth by physical vapor transport method

“…SiC has a great potential for devices operating at high temperatures, high power and high frequency [1][2][3]. Bulk SiC crystals are commonly grown by the physical vapor transport (PVT) method.…”