Low sodium polishing solution and preparation method and application thereof

Abstract

The invention discloses low sodium polishing solution. The low sodium polishing solution comprises the following raw materials in parts by weight: 20-40 parts of silicon dioxide, 1-5 parts of fatty alcohol polyoxyethylene ether sodium sulfate, 1-6 parts of calcium lactate, 1-10 parts of aluminum hydroxide, 0.5-2.5 parts of diethanol amine, 0.5-2.5 parts of hydroxyquinoline, 10-20 parts of hydroxypropyl methyl cellulose, and 40-60 parts of deionized water. A preparation method for the low sodium polishing solution comprises the following steps: selecting a suitable amount of the fatty alcohol polyoxyethylene ether sodium sulfate, the diethanol amine, the aluminum hydroxide, the hydroxyquinoline and the deionized water according to a weight matching ratio, placing the raw materials in a stirring kettle, and stirring for 5-15 min in a condition of 60-80 DEG C, wherein a stirring speed of the stirring kettle is 100-300 r / min; putting the silicon dioxide, the calcium lactate and the hydroxypropyl methyl cellulose into the stirring kettle, stirring in a warming condition, wherein the stirring speed of the stirring kettle is 600-1200 r / min; and 3) adding a pH value regulator, after filtering, to obtain the polishing solution. The low sodium polishing solution is capable of improving washing efficiency of a wafer, reducing scratching probability, and effectively reducing later period waste liquid treatment cost of the polishing solution, thereby improving the cmp polishing effect.

Description

technical field [0001] The invention relates to the field of polishing liquid, in particular to a low-sodium polishing liquid and its preparation method and application. Background technique [0002] The initial polishing of semiconductor substrates (substrate wafers) followed mechanical polishing, such as magnesium oxide, zirconium oxide polishing, etc., but the resulting wafer surface damage was extremely serious. Until the end of the 1960s, a new polishing technology - chemical mechanical polishing technology (CMP Chemical Mechanical Polishing) replaced the old method. CMP technology combines the advantages of chemical and mechanical polishing: pure chemical polishing, fast polishing rate, high surface finish, low damage, good flatness, but poor surface flatness and parallelism, poor surface consistency after polishing; simple mechanical polishing The polished surface has good consistency and high surface flatness, but the surface finish is poor and the damage layer is d...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, the polishing liquid used in CMP technology generally has the problems of high sodium and acid radicals, high pollution of wastewater, and high cost of wastewater treatment in the later stage. prone to scratches

Images