CMP Slurry Analysis

Measuring Hydrogen Peroxide in CMP Slurry

CMP is used in fabs to polish the surface of silicon wafers and remove imperfections as layers of circuitry are deposited. Small drift in the composition of CMP slurries can lead to defectivity, raise cost-of-ownership, and cause micro-scratches or corrosion.

A major aspect of maintaining CMP slurry health is keeping the concentration of the oxidizer (often H2O2) constant as per specification in the slurry/oxidizer blend. As chipmakers continue to squeeze in more transistors, more layers of circuitry must be smoothed by CMP—leaving more to be gained from slurry health analysis. Delivery method, filtration type, and replenishment cycle are all significant causes for slurry degradation.