SBIR-STTR Award

Light scatter has bean used to map and size particleson silicon wafers for many yearn producing accurate maps of particle position and giving an indication of particle size, but do not reveal any information about particle composition. Today's technology is limited by noise, precluding detection ofthe smallest particles of interest. Present Instruments are notadequate for the next generation of semiconductor devices.Experimental and theoretical studies indicate that moreinformation can be obtained from light scattered by particles theis presently being utilized. Through a combination ofmeasurements and nodding, it should be possible to identity anoptimum configuration (geometry, wavelengths polarization, etc.)for a scattering instrument. Work includes experimentalverification of theoretical scatter models, noise analyst,development of numerical models, selection of potentialinstrument configurations, comparison and optimization ofconfigurations and development of specifications for a prototypeinstrument.If successful, this approach will lead to a prototype instrumentcapable of detecting and clashing particles as small as 0.06um onsilicon wafers. This will support the goals of the NationalTechnology Roadmap for Semiconductors through the 0.18um processgeneration.Potential commercial applications of the research:An instrumentbased on a successful Phase I and Phase II effort will becommercialized by ADE Corporation, a technology leader in thefield of semiconductor characterization. Another potentialapplication is residual material analysis in areas such asforensic science.

Light scatter signals in laser scanners have been used for many years to map and approximately size particles on silicon wafers; however, these measurements do not give any indication of particle composition. Current scanner technology is not adequate for the next generation of semiconductor devices.Our Phase 1 research resulted in an instrument geometry that allows detection of 0.06 µm particles, as required by the National Technology Roadmay for Semiconductors. In addition, by utilizing a unique source/detector approach, we developed a measurement that is sensitive to differences in particle composition. Knowing the particle composition is important for both accurate sizing and determining the contamination source. This work includes building a prototype that combines existing ADE product components with the new detection techniques in the new instrument geometry. By locating the prototype in the same lab as the Phase 1 research scatterometer and a particle deposition system, it will be possible to optimize the technique for both small particle detection and classification capabilities.This work is expected to result in a product design that will become an important tool for the semiconductor industry and a major part of ADE Optical Systems business plan.Commercial applications:An instrument based on a successful Phase 1 and Phase 2 effort will be commercialized by ADE Corporation, a technology leader in the field of semiconductor characterization. Another potential application is residual material analysis in areas such as forensic science.