Halbert Tam, JSR Micro, Inc., Sunnyvale, CA, USA & Nobuo Kawahashi, JSR Corporation, Yokkaichi, Japan
ABSTRACT
For Cu/low-k integration at 65 nm or beyond, development on soft CMP polishing is essential to minimize the defectivity. While conventional approaches to defect reduction involve using lower polish pressures, lower polish speeds and slurry filtration to control particle-size distribution, more fundamental changes in CMP consumables may be necessary to provide solutions for the 65-nm node and beyond. To meet these more stringent defect requirements, JSR has developed a low-defectivity CMP process through engineering of a soft abrasive slurry and a polymer-based solid pad. This article will present this approach to defect reduction through design of CMP consumables. Data will be shown that, by design, the compressible nature of the abrasive and soft top layer of the solid pad enable low-defect polishing while maintaining high copper removal rates and planarization capability.