Microreplicated conditioners for Cu barrier chemical-mechanical planarization (CMP)

Abstract

Removal rates of low-k SiCOH dielectric and scratch defect density of Cu barrier CMP on a soft polyurethane pad with conditioning are characterized and compared between conventional diamond tip conditioner and two types of microreplicated diamond-coated conditioners.Data collected from high volumemanufacturing environment demonstrate stable and uniform SiCOH removal rates plus lower scratch density with up to 1000 wafer passes on the soft pad with the microreplicated conditioners, relative to the conventional diamond tip conditioner. Scratch defects are categorized based upon their length and severity. The formation mechanism for each type of scratches are hypothesized. Groove depth and asperity height of soft pads are analyzed in order elucidate the observed differences in removal rates and scratch density with various different pad conditioners.