CMP and Colloidal Analysis
CT Associates utilizes a liquid nanoparticle sizer (LNS) to determine the size distribution of nanoparticles in chemical-mechanical planarization (CMP) slurry, solutions, or colloidal suspensions. This method has the unique capability of measuring number concentration for particle sizes ranging from 2.5 to 500 nanometers. In addition, this method has the ability to readily distinguish multimodal particle size distributions.
LNS Measurement of a Multimodal Nanoparticle Mixture
Additional methods used for measuring particle size distribution include dynamic light scattering for measuring the working particle size distribution and light scattering/extinction techniques for characterizing the large particle tail (>0.56 microns).
By combining techniques we can characterize changes to the large particle tail and working particle size distribution with slurry circulation and usage. Using these techniques the effect of system components, such as valves and pumps, on slurry particle size distribution can be determined. Our capability for characterizing particle mixtures can be applied to other systems as well, such as nanoparticle suspensions and emulsions. In addition to measuring overall physical characteristics, particles populations can be captured and their composition determined.