ScholarWorks@중앙대학교

초록

In this study, a multi-wavelengths Raman spectroscopy method was employed to evaluate the quality of epitaxial grownsilicon (Epi-Si) wafers by analyzing defects, stress, and crystallinity. Unlike conventional electrical property analysis,which is typically conducted post-process through device failure testing, this study demonstrated the potential for nondestructiveand real-time assessment of thin film properties at the wafer stage using Raman spectroscopy. By comparingtwo 8-inch wafers fabricated under different deposition conditions, Raman shift and Full Width at Half Maximum(FWHM) were established as primary evaluation indicators to analyze the point-specific characteristics of the wafers. Weapplied multi-wavelength Raman spectroscopy with 532 nm and 405 nm laser to measure stress distribution of wafer -scale Epi-Si layers and compared it with wafer failure maps to demonstrate the validity of stress analysis of thin filmsusing Raman spectroscopy. The residual stress and FWHM of epitaxially grown Si thin films were quantitatively analyzedfor 9 points of Epi-Si. The point-by-point residual stress and crystallinity evaluations measured by Raman spectroscopywere in good agreement with the wafer failure map, and the stress variation in the failure region could be evaluatedhighlighting g potential of Raman spectroscopy enabling precise analysis across a broader range of samples and havingthe practical utility for non-destructive, early-stage assessment of thin film properties, as well as for the in-situ detectionof defects and stress.

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