Raman-Based Residual Stress Measurement and Defect Evaluation in Multistage-Processed 4h-Sic Wafers

Abstract

This study investigates the residual stress in single-crystal silicon carbide (SiC) wafers produced by wire slicing and subjected to multi-stage grinding processes (#2000, #8000, #30000). Single-crystal SiC wafers exhibit excellent thermal conductivity, chemical stability, and superior mechanical properties, making them critical materials for high-performance electronic devices. Consequently, the processing quality of these wafers profoundly impacts device reliability and efficiency. Experimental results reveal that the abrasive grain size significantly influences the wafer’s residual stress distribution post-grinding. Compared with traditional optical inspection methods that rely on extensive image-based analyses, Raman spectroscopy demonstrates higher sensitivity and detection efficiency, allowing rapid and accurate identification of areas with abnormal residual stress. This study's measurement and analysis approach offers a comprehensive and practical framework for controlling residual stress in subsequent precision processing of wide-bandgap semiconductor wafers. Furthermore, the findings serve as a valuable reference for substrate processing and quality management in high-performance power electronic devices, improving yields and enhancing overall device reliability.

Keywords: single-crystal silicon carbide, slicing, grinding, Residual stress, Raman