Advancements in integrated circuit design rely on Chemical Mechanical Planarization (CMP) to extend Moore’s law by reducing surface topography. CMP utilizes a complex dispersion (i.e. slurry) containing abrasive nanoparticles and additives to reduce substrate defectivity and achieve angstrom level uniformity. However, the implementation of slurry formulations results in additional surface defects generated by residual contamination (i.e. abrasive particles, organic residues, pad remnants, etc.) contingent on post-CMP (p-CMP) cleaning methods. PVA brushes coupled with chemistry are employed as the leading strategy in p-CMP cleaning for contaminate removal but have limited efficiency due to a reliance on shear and compressive forces. The inability of PVA to complex with residual contamination results in current p-CMP cleaning strategies having the propensity to redeposit particle back onto the substrate’s surface which may result in additional defects. Due to the continued miniaturization and increased fragility of semiconductor devices, novel brush technology aims to enhance p-CMP cleaning through the alteration of micro properties (i.e. composite functionalization and coordinated brush-chemistry interactions) to reduce friction at the liquid-brush interface while inhibiting the occurrence of particle redeposition. This work focuses on the utilization of a polyvinyl alcohol (PVA) polymer backbone functionalized with supramolecular and complexing molecules to develop a chemically active p-CMP brush to reduce additional defectivity through enhanced debris transfer. More specifically, the development of novel brush composites aims to produce a soft, low shear force approach to Cu p-CMP cleaning by chemically modulating the brush matrix with coordination and inclusion complex forming molecules (i.e. amino acids and cyclodextrin) to effectively remove organic residue encapsulated metal ions (M+). Initial results have shown, chemically modulated brush composites achieve the removal of organic residue and uptake of metal M<sup>+</sup> into the polymer backbone resulting in the elimination of organic residue/particle (i.e. CuO) redeposition. Additionally, enhanced removal of organic residue encapsulated metal ions has been shown to reduce shear force at the liquid-brush interface.

Development of novel polymeric composites for low shear force copper (Cu) post-chemical mechanical planarization (p-CMP) cleaning

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.