9361544 Markham Advanced Fuel Research Inc. (AFR) has pioneered a technique to determine temperatures along a "line-of-sight" into transparent materials. It involves measuring infrared radiance spectra, for materials with well-characterized, temperature-dependent optical constants. The objective this proposal is to demonstrate that Fourier Transform Infrared (FT-IR) radiance spectra can be used to extract the average temperature at the slurry-sample interface during micromachining processes. Feasibility will be demonstrated by performing FT-IR radiance measurements through samples to the slurry interface, for two systems: colloidal silica lapping of sapphire, and diamond lapping of silicon. The latter case represents the dicing of silicon wafers. At present there is no way to measure the slurry-sample interface temperature during micromachining. The successful completion of Phases 1 and 11 would lead to an on-line process monitor for the micromachining of single-crystal ceramics, as well as to increased understanding of the processes involved. ***