Soft Chemical Mechanical Polishing Pad for Oxide CMP Applications
Nandan Baradanahalli Kenchappa, R. Popuri, Ashwin Chockkalingam, Puneet Jawali, Shiyan Jayanath, Daniel Redfield, Rajeev Bajaj
Abstract
Chemical mechanical polishing (CMP) is widely accepted as the best planarization technique for fabricating nanoscale devices. A soft CMP pad that can enable higher oxide removal rates (RRs) and good planarity has been proposed for oxide CMP applications. In this study, three pads namely, Pad-1 (hard), Pad-2 (soft), and a commercial pad (hard) were used to polish blanket oxide, and STI patterned wafers. The Pad-2 demonstrated significantly higher RRs and better planarization than the hard pads. Post-polish pad texture analysis on Pad-2 showed a uniform surface asperity distribution. This is due to the novel method of pad manufacturing, which enables precise material placement and consistent pore construction.