Production technology of high performance slurry without CMP dispersing agent

A new media-less wet jet mill method has been developed to produce high performance, long stability slurries for CMP (chemical-mechanical polishing). This method features the injection of the coagulated slurries into a nozzle through a small orifice under high pressure (25-200 MPa), which causes collision, inducing the dispersion of the coagulated slurries. With this machine, an experiment of fine dispersing process was carried out using the preliminary dispersed slurries (sample) of the primary particle size of 20 nm. The result proved that this new dispersing machine was capable of producing slurry of good dispersibility independently from any kind of dispersing agent. The slurry that had been adjusted to the median particle size of 70 nm and dispersed, was subjected to the stability test for 80 days. Despite that period, the result did not show any change in the particle size, which, in other words, confirms that any second coagulation did not occur in the slurry. From the foregoing, a good perspective to apply such slurry as an ultrahigh purity slurry for CMP was attained which makes work surfaces of high quality.