This study focused on characterizing cerium oxide and silica-alumina based ILD polish slurries in terms of their tribology, fluid dynamics behavior and ability to remove silicon dioxide (SiO_2) and silicon nitride (Si_3N_4) films. The methods used in these studies were real-time frictional force analysis, as well as real-time dual emission UV-enhanced fluorescence during polish. It was found that: 1. The values of COF associated with cerium oxide and silica-alumina abrasives were nearly the same. 2. The tribological mechanism associated with cerium oxide and silica-alumina abrasives was shown to be asperity contact between the wafer and the pad with the abrasive particles participating in the overall polish by acting as roller bearings. 3. One-percent cerium oxide slurry yielded the same COF as 10-percent silica slurry. 4. In the case of cerium oxide slurries without additives, COF was the same regardless of the type of film being polished. When additive was present, COF was approximately 25% lower for silicon nitride wafers compared to silicon dioxide wafers. 5. The above COF differences were used to explain the observed 100-to-1 selectivity between silicon dioxide and silicon nitride surfaces. 6. A preliminary model based on electrostatic forces was presented which qualitatively explained the above trends the results obtained with the anionic additive. 7. Mean residence time was shown to vary with slurry flow rate and platen speed in manner consistent will well-established chemical engineering reactor design theories. 8. Mean residence time was shown to strongly depend on cerium oxide abrasive concentration and presence of anionic organic additive. 9. A preliminary fluid dynamics model was developed which helped explain these trends and supported earlier findings on the effect of additives on COF. 10. It was shown that surface texture of the pad (due to perforation or grooving) significantly affected mean residence time. This effect was explained by taking into account the macro-void volume associated with each pad and applying it to the classical definition of mean residence time. 11. Silica abrasives with varying alumina content (both in magnitude and location), mean aggregate size, primary particle size and degree of structure were shown to significantly affect Preston Constant during ILD polish. Due to experimental confounding, the relative contribution of each of these parameters with respect to removal rate was unclear.
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