Optical charcaterization of industrial slurries

In this work we focus at the characterization of micro- and nano-powders typically adopted for chemical mechanical polishing, extensively exploited whenever global and local planarization of surfaces is required as in nanoelectronic fabs. We present an innovative method for accurate characterization of water suspensions of nanoparticles. It relies upon the combination of a new approach to extract light scattering information from single particles and the recently developed diagnostic tool named Single Particle Extinction and Scattering. It can be exploited in line. Data interpretation becomes independent of any a priori assumption about the samples. The results of accurate measurements performed on Ceria as well as Aluminum oxide surries are reported. We show strong advantages of this method with respect to traditional ones by explicitly reporting experimental results on calibrated spheres made of different materials. We discuss possible applications for in line characterization of ultrapure water, chemicals, slurries for abrasive processes, for example, as well as the detection of any undesired particles could be the key for future improvements of advanced process control systems.