Silicon carbide chemical mechanical polishing liquid with improved pH stability and its application

Abstract

The invention provides a silicon carbide chemical mechanical polishing liquid with improved pH value stability, wherein the polishing liquid comprises an oxidizing agent, a high-hardness abrasive material and a pH value stabilizer, and the pH value stabilizer is aluminum nitrate. According to the present invention, the polishing liquid can well maintain the pH value stability during the chemical mechanical polishing, and has advantages of good dispersion stability and uniform dispersion; by adding the pH value stabilizer aluminum nitrate to the polishing liquid, the pH value stability of the polishing liquid during the chemical mechanical polishing is strong, and the polishing liquid is not easily subjected to hard agglomeration; and the polishing liquid is environmentally friendly, and can be used in a circulating material supply manner.

Description

technical field [0001] The invention relates to the technical field of chemical mechanical polishing, in particular to a silicon carbide chemical mechanical polishing liquid with stable pH value and application thereof. Background technique [0002] Due to the high hardness (9.5) and strong chemical inertness of silicon carbide, the polishing speed of alkaline hydrogen peroxide-silicon oxide CMP polishing fluid is very low (<50nm / hr), for two reasons: one is the hardness of silicon oxide Small (6-7); Second, the chemical action of the oxidizing agent is weak under alkaline conditions. Therefore, the use of α-Al whose hardness is second only to silicon carbide 2 o 3 The acidic (pH<7, especially pH<4) silicon carbide chemical mechanical polishing fluid of the abrasive has become the mainstream. [0003] In order to improve chemical oxidation, potassium permanganate has become the most widely used oxidant, but potassium permanganate will consume H during the oxidati...

AI Technical Summary

Problems solved by technology

The CMP polishing liquid of ASAHI GLASS company uses potassium permanganate as the oxidizing agent and acidic silicon oxide or cerium oxide as the abrasive. During the use of the polishing liquid, the pH value cannot be controlled, and the abrasive hardness is low. Therefore, the CMP polishing liquid of ASAHI GLASS company The polishing efficiency of silicon carbide is low

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