Pad thermal data taken with an infrared video camera during chemical mechanical polishing of copper at different slurry flow rates is analyzed using a model developed to explain pad heating during oxide polishing. After minimal recalibration to match thermal data as a function of time and pad radius at one flow rate, the model is able to correctly predict the variation in temperature as the flow rate is changed. Periodic thermal oscillations in the data that are not present in oxide polish data are also modeled and are attributable to in situ conditioning. Theoretical estimates of the wafer temperature suggest that the temperature rise of the wafer above ambient may be significantly higher than what is measured on the pad near the leading edge of the wafer.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry