Angstrom surface with high material removal rate for quartz glass induced by silk dissolved novel green chemical mechanical polishing

Abstract

Quality and efficiency are a pair of everlasting contradiction for manufacturing, and therefore it is a challenge to achieve an atomic surface with high material removal rate (MRR). Toxic and corrosive slurries are widely employed in traditional chemical mechanical polishing (CMP), facing challenges to treat the detrimental slurries during and after CMP. To solve these challenges, natural extract of sodium alginate (SA) and ceria are used to develop green CMP. Dissolved silk is firstly applied to shear thickening and enhance MRR in CMP. After CMP, surface roughness Sa is 0.08nm on the surface of quartz glass at a scanning area of 20×20 μm2, and MRR is 33.215 μm/h, and thickness of the damaged layer is 5.09nm. To the best of our knowledge, the surface roughness is the lowest and MRR is the highest for quartz glass, compared with those reported previously. Density functional theory and molecular dynamics simulations reveal that dissolved silk is adsorbed onto the surface of quartz glass, forming a complex with SA and facilitating the removal of surface atoms. Additionally, the developed novel green slurry of CMP demonstrates bio-compatibility and degradability. These outcomes suggest new viewpoints that using a dissolved silk slurry of ceria breaks the eternal contradiction between efficacy and surface roughness to achieve atomic surface with high MRR via green CMP.