Study on polishing slurry of hydrogen peroxide-oxalic acid in CMP 304 stainless steel

Stainless steel will become the substrate material of the flexible display, requirements of the flexible substrate in the surface quality and performance are very strict. Chemical mechanical polishing (CMP) is one of the most appropriate technologies to achieve the surface processing of ultra-thin stainless-steel flexible display substrate with ultra-smooth and damage-free. In this paper, the design of CMP slurry of 304 stainless steel on the hydrogen peroxide-oxalic acid type was proposed. Through experiment and analysis, the basic ingredients of CMP slurry was obtained. The research results showed that the hydrogen peroxide can increase the hydrophilicity of the stainless steel surface, and the Fenton type Haber-Weiss reaction can occur on the surface of the fresh metal substrate of stainless steel. The trivalent iron ions generated by the Fenton type reaction combined with oxygen to generate iron oxide and promoted the removal of the surface material. Under acidic conditions, the oxalic acid can decrease the stability of the oxide film on the stainless steel surface, promote the diffusion of oxygen into the metal interface, improve the oxygen reduction reaction, and increase the material removal rate. The results will provide an important reference for the next researching the CMP slurry of 304 stainless steel