Coupling Supramolecular Assemblies and Megasonic Energy for Improved p-CMP Cleaning of Silicon Carbide

Abstract

Wide band gap (WBG) materials (i.e. Silicon Carbide (SiC)) are rapidly emerging in the semiconductor arena because of their properties (i.e. high capacitance, thermal stability, and wear resistance), which allow these substrates to be used as insulating wafers and transistors in integrated circuits (IC). During CMP, removable defects (i.e. particles, organic residues, pad debris etc.) and non-removable defects (i.e. scratches or corrosion) are generated on the wafer surface. Industry standards currently utilize aggressive post-CMP processing conditions, which may lead to further defectivity. This research focuses on a comparison between an industry-standard brush cleaning (i.e. contact mode) and an emerging megasonic cleaning approach (i.e non-contact mode). Implementation of supramolecular cleaning chemistries such as micelles, vesicles, and polyelectrolytes will be employed in both modes as an alternative “soft” cleaning process. Initial results indicate a correlation between the structure of the “soft” cleaning additives on overall simulated defect removal. In addition, significant concentration dependency (i.e. above and below the critical micelle concentration (CMC)) emerged as a key driver for the rate of defect removal.