IN-SITU INTERFACIAL TEMPERATURE DETERMINATION DURING MICROMACHING

RESEARCHERS HAVE 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 PROJECT DEMONSTRATES 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 IS 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. AN ON-LINE PROCESS MONITOR IS BEING DEVELOPED FOR THE MICROMACHINING OF SINGLE-CRYSTAL CERAMICS AS WELL AS TO INCREASE UNDERSTANDING OF THE PROCESSES INVOLVED.