New High Resolution Method to Characterize CMP Slurry Particle Size Distributions

A new method has been created to more easily and accurately measure particle size distributions (PSD) in Chemical Mechanical Planarization (CMP) slurries from a few nanometers to one micrometer in size. It combines the use of a newly developed nanoparticle atomizer (NPA) and a Scanning Mobility Particle Sizer (SMPS
^TM
), and requires only uncomplicated process steps of dilution and injection. This new method provides a straightforward means of assessing slurry characteristics even down to nanometer-sized particles, which are now being used in the semiconductor industry with increasing frequency. Such measurements enable improved qualification of outgoing or incoming slurries, the opportunity for better monitoring and control of CMP parameters (in process development, or in-line) to reduce defects and waste, as well as to monitor slurry aging.