• Journal of the Microelectronics and Packaging Society
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• v.10 no.4
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• pp.53-60
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• 2003

CCD(Charge-Coupled Device) wafers, with a layer of micro lenses on top, usually are not passivated with dielectric films. Micro lenses, in general, are made of polymer material, which usually has a large affinity for particles generated in the various chip fabrication processes, most notably the wafer sawing for chip-dicing. The particles deposited on the micro lens layer either seriously attenuate or deflect the incoming light and often lead to CCD failure. In this study we introduce new type of saws which would significantly reduce the particle-related problems found in conventional type of saws. In the new saws, the positions and diverging angles of side and center nozzles have been optimized so as to flush the particles effectively. In addition, an independent nozzle is added for the sole purpose of flushing the generated particles. The test results show that, with the new saws. the ratio of the particle-related CCD chip failures has been dropped drastically from 9.1% to 0.63%.