Communication—In-Line Detection of Silicon Surface Quality Variation Using Surface Photovoltage and Room Temperature Photoluminescence Measurements

Occasionally, in volume device manufacturing, a large number of particles may be generated on cleaned Si wafers. Surface (ionic, organic and/or metallic) contamination is generally suspected. However, conventional chemical analysis techniques for contamination are generally not able to distinguish between Si wafers with good and poor particle performance. No suspicious chemicals and elements were detected from any wafers regardless of characterization techniques. Surface photovoltage (SPV) measurement barely showed the differences between wafers with good and poor particle performance. Multiwavelength room temperature photoluminescence (RTPL) showed significant differences in intensity between them, indicating the presence of surface quality variations.