Synthesis, characterization of CeO2@ZIF-8 composite abrasives and their chemical mechanical polishing behavior on glass substrate

As a kind of abrasive, cerium oxide (CeO2) abrasive provides the most key support for glass planarization, whose material removal rate (MRR) is related to the concentration of Ce3+ in the CeO2 surface. Herein, a series of composite abrasives named zeolite imidazolium cerium oxide (CeO2@ZIF-8) were prepared to increase the concentration of Ce3+ by growing different amounts of zeolitic imidazolate framework (ZIF-8) material on the cerium oxide particles, and their polishing properties on glass substrates were evaluated. When the content of ZIF-8 in the CeO2@ZIF-8 composite abrasive is 1.95 wt%, the MRR using this abrasive can reach up to 22.2 μm/h, which is 28% higher than that of pure ceria abrasive, while a lower average surface roughness (Sa, arithmetic mean height) of 1.23 nm can be obtained. The X-ray photoelectron spectroscopy results revealed an increase in the concentration of Ce3+ ions in the CeO2@ZIF-8 composite abrasive surface. The contact angle tests indicated that the slurries containing CeO2@ZIF-8 abrasives had superior wettability on glass substrate. Therefore, under the synergy of the two aspects, the chemical reaction process between CeO2@ZIF-8 composite abrasives and the glass substrate is remarkably promoted, resulting in outstanding polishing performance. We believe this work adds valuable insights regarding glass CMP by using CeO2@ZIF-8 as abrasives.