Research on Defect Control Technology of Wide Bandgap Semiconductor Substrates Centered on SiC

This paper integrates various types of literature and describes various defects generated during the crystal growth process.Then the various defects generated were classified into the interior, surface and near-surface of the crystal, and the causes of the defects were described.Secondly, this paper expounds the three stages of SiC substrate manufacturing, namely crystal growth, epitaxial process and post processing, and introduces the defect control technology among them at the same time.Among them, the repeated a-face growth technique (RAF) can effectively reduce the dislocation density through dislocation direction conversion.The solution growth method can convert dislocations in the thermodynamic equilibrium state.Optimizing the flow rate of HCl gas in the epitaxial process can suppress the formation of triangular defects.The improvement of vertical high-speed rotating CVD equipment can enhance the epitaxial uniformity.Furthermore, femtosecond laser technology is highly efficient and low-loss, and annealing technology can indirectly reduce the formation of dislocations.This paper argues that the process equipment can be optimized to reduce defects, and at the same time, the growth rate can be precisely regulated to control the defects.