Alkaline polishing solution for reducing CMP defects of multi-layer copper interconnection barrier layer and preparation method of alkaline polishing solution

Abstract

The invention belongs to the field of polishing solutions, and particularly relates to an alkaline polishing solution for reducing CMP defects of a multi-layer copper interconnection barrier layer anda preparation method of the alkaline polishing solution. The polishing solution is prepared from the following components in percentage by mass: 5 to 20 percent of silica sol, 0.1 to 5 percent of a chelating agent, 0.001 to 5 percent of a surfactant, 0.001 to 10 percent of an oxidant and the balance of deionized water, wherein the surfactant is obtained by compounding a non-ionic active agent andan anionic active agent. The polishing solution is alkaline, the pH value is 7.5-11, equipment is not corroded, and the environment is not polluted. The nano SiO2 sol is used as a polishing solutionabrasive, and is high in concentration, good in dispersity and small in hardness. The alkaline polishing solution is composed of the silica sol, the chelating agent, the surfactant, the chelating agent, the oxidant and the deionized water, and is simple in component, good in stability and low in price.

Description

technical field [0001] The invention belongs to the field of polishing fluids, and in particular relates to an alkaline polishing fluid for reducing CMP defects of multilayer copper interconnect barrier layers and a preparation method thereof. Background technique [0002] At present, the development trend of integrated circuit technology is: the size of the wafer increases, the number of active devices increases, and the feature size decreases. Then planarization becomes more challenging, and at the same time, more stringent requirements are put forward for the planarization effect: flat surface, as small as possible surface damage, and sufficiently small surface roughness. Then, as a key technology to achieve global planarization of large-size wafer chips, the role of chemical mechanical planarization (Chemical Mechanical Planarization, CMP) is becoming more and more important. [0003] As the main planarization technology, CMP realizes the planarization of the material s...

AI Technical Summary

Problems solved by technology

Research has found that CMP scratches cause not only initial failure but also long-term reliability failures and lead to device failure, yield loss, and potential reliability issues

Previous researchers mentioned that by adding a slurry filtration system to reduce the number of large particles and thereby reduce scratches, but when the abrasive particles in the slurry come into contact due to Brownian motion, they tend to stick to each other to form agglomerates

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