non-contact metrology

**Non-Contact Metrology** encompasses all **semiconductor measurement techniques that do not physically touch or damage the wafer** — using optical, electromagnetic, or acoustic interactions to measure thickness, composition, stress, defects, and electrical properties without contamination risk. **Key Non-Contact Techniques** - **Ellipsometry**: Film thickness, refractive index, composition. - **Reflectometry**: Film thickness from interference fringes. - **Raman**: Stress, composition, crystal quality. - **Eddy Current**: Sheet resistance of metal films. - **Corona-Kelvin**: Dielectric quality (oxide thickness, flatband voltage). - **PL**: Material quality, band gap, defect density. **Why It Matters** - **Zero Contamination**: No probe contact means no risk of introducing particles or metal contamination. - **Production-Compatible**: Can be used on production wafers without scrapping them. - **100% Sampling**: Non-contact tools can measure every wafer, not just test wafers. **Non-Contact Metrology** is **measurement without touching** — the gold standard for production-compatible semiconductor characterization.