| The planarization abilities of Chemical Mechanical Polishing (CMP) have led to its pervasive use in integrated circuit fabrication lines. As a result, CMP has emerged as a critical processing step for the realization of circuits with current line widths as small as 0.10 microns and has generated wide-ranging research activity from both academic and government institutions as well as industrial chipmakers.; In this dissertation, investigations on several topics related to the mechanical aspects of Chemical Mechanical Polishing were conducted. Based on previous experimental work, the effect of slurry film thickness on the material removal mechanism in CMP was extended to patterned wafer polishing. Using a relative Hersey Number as a metric for film thickness, a range of conditions that varied pressure and velocity were used to correspondingly alter the slurry film thickness. Under these conditions, the step height reduction and material removal rate were significantly affected for various line densities on the patterned wafers.; Pertinent to today's competitively intense semiconductor manufacturing industry, an investigation was conducted on scratch defects, which have well-known detrimental effects on production yield. Two-body scratches, which emulate the commonly observed defects from process contamination, were characterized for brittle and ductile materials. The removal of these scratch defects was shown to require a substantial amount of polishing beyond the original depth of the scratch.; Furthermore, process monitoring techniques for end-point detection systems were surveyed and a fundamental study using acoustic emission sensing was performed. Recently, acoustic emission sensing technology has advanced to a state that shows applicability to very small-scale material removal mechanisms that are typical in precision manufacturing processes. The basic study showed the sensitivity of acoustic emission to the abrasives that are actively involved in the material removal mechanism. Finally, the design and implementation of a web-based software tool, CMPSim, effectively demonstrates the development of very complex CMP modeling work. The software was implemented as a unique visualization tool to show the sensitivity of an array of input parameters to the CMP model. CMPSim serves to establish a framework for educating users and helping them interpret the continuous advancement of future CMP research. |
