Effects of pH and Oxidizer on Chemical Mechanical Polishing of AISI 1045 Steel

摘要

AISI 1045 steel has been widely used as the substrate for thin film deposition. In some cases, an ultra-smooth surface of AISI 1045 steel is needed and is even indispensible for the satisfactory deposition of thin film. In this paper, chemical mechanical polishing technique was employed to prepare the ultra-smooth surface of AISI 1045 steel. The effects of pH and H2O2 on the polishing performance of AISI 1045 steel were investigated. It is revealed that, with the increase of pH, the material removal rate (MRR) and the static etching rate (SER) of AISI 1045 steel gradually decrease due to the formation of passive iron oxides on the top surface, and thus the surface quality gradually improves. At pH 4.00, with the addition of H2O2, the SER of AISI 1045 steel is further suppressed; while the MRR of AISI 1045 steel first dramatically increases due to the formation of porous iron oxides with relatively low mechanical strength on the surface when the H2O2 concentration increases from 0 to 0.01 wt%, and then decreases since the porous iron oxides gradually grow compact when the H2O2 concentration further increases. The increase of the compactness of the iron oxides might be attributed to the crystallization of gamma-FeOOH into alpha-Fe-OOH and even into alpha-Fe2O3 and the resulting polymerization of the amorphous iron oxides.