Common perception is that a diamond-conditioning disk of one set of characteristics would perform equally and optimally for all known CMP processes. This concept is outdated and costing the wafer fabs significant time, money, yields and quality. Just as slurries, pads, and process parameters differ for the various CMP processes1; a process optimized diamond-conditioning disk is warranted. The technology now exists to design and manufacture diamond-conditioning disks for specific CMP processes on any equipment platform. The ability to optimize the polishing pad removal rate through diamond conditioning disks for various CMP processes is desired. Surface characteristics and removal rates of polyurethane polishing pads can be controlled and accurately manipulated through the selection of diamond crystal type. This relationship holds true for both randomly placed and structured grid diamond crystal arrangements. A relationship between diamond type and its impact on polishing pad removal rate and RAS (relative abrasive sharpness) of the conditioner disk was established. Diamond concentration was held constant for this study. Polishing pad removal rates generated by the diamond-conditioning disk were measured using a special test apparatus that simulated standard CMP processes and setup. RAS values were measured using Abrasive Technology proprietary equipment. This paper presents details of diamond disk characteristics, test methodologies, test results, and field relevance.
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