Process Gas Control for High-Resistance HPSI-SiC Growth

In this study, we tried to grow SiC ingots with high resistivity and polytype stability with adoption hydrogen mixed gas flow to the PVT method. Three different types of growth atmosphere of N 2 +Ar, H/Ar ratio:10% and 30% were employed. The polytype inclusion, crystal shape and transparency, and their resistivity were systematically investigated by UVF images, exposing backlighting, and high resistivity analysis using COREMA (Contactless Resistivity Mapper), respectively. The SiC ingot grown with adoption N 2 +Ar exhibited a suppression of polytype inclusion, a convex shape and a lower resistivity. In contrast, the SiC ingot with more higher H/Ar ratio of 30% than that of 10% shows no polytype inclusion and highest resistivity of 1.7E11mΩ∙cm. The growth atmosphere of relative higher H/Ar ratio in SiC crystal growth could be led the way to manufacture HPSI (high-purity semi-insulating)-SiC single crystal with polytype stability.