The status of SiC bulk growth from an industrial point of view

Thermoelastic stresses in SiC single crystals grown by the physical vapor transport method

“…For 4H/6H SiC with hexagonal structure, gliding can occur in the basal (0 0 0 1) plane [14,15], and the shear stress component, τ rz , and the von Mises stress are usually used as the resolved shear stress [2][3][4][5][6][7][8]. Here the von Mises stress is defined by…”

“…• C [5], so the plastic deformation and dislocation formation will take place in the crystal. The high von Mises stress in the region near the graphite lid will cause a relatively high dislocation density in the crystal near the graphite lid.…”

“…The high von Mises stress in the region near the graphite lid will cause a relatively high dislocation density in the crystal near the graphite lid. However, it should be noted that the generation and multiplication of dislocations in the SiC crystal are non-linear functions of thermal stress and time [5]. The linear elastic model is only a qualitative description of thermal stresses.…”

“…Chen et al [4] for the first time proposed a growth kinetics model which assumes that the growth rate is proportional to the supersaturation of the SiC vapor species at the growth interface and the growth rates in a 75 mm growth system were predicted. Thermally induced stresses in the growing crystals were calculated in past years [5][6][7][8][9]. The dependence of thermal stress on growth conditions and the influence of thermal stress on dislocation formation were studied.…”

Micropipe Reactions in Bulk SiC Growth

“…One can see that the stress τ 0 reduces the energetic barriers for the dislocation exchange. In the range of stress values from 10 to 100 MPa, which are characteristic for bulk SiC growth (Ma et al, 2003;Müller et al, 2000), the first barrier decreases weakly while the second one strongly. The first barrier has the height of about 1.5Gb 2 0 /π per unit dislocation length, which for a 4H-SiC crystal with G = 165 GPa and b 0 = 1n mg i v e s≈ 0.48Gb 2 0 l ≈ 125 eV per unit distance l ≈ 0.252 nm between basal atomic planes.…”