Chemical and mechanical polishing method for sulfur phase-change material

Abstract

A chemical and mechanical polishing method for a sulfur phase-change material comprises the following steps: 1) roughly polishing the sulfur phase-change material to quickly remove most of sulfur compound outside through holes in an inlaid structure; and 2) performing ultrafine polishing on the sulfur phase-change material which is roughly polished to remove the rest sulfur compound outside the through holes and expose a final through hole array structure. A polishing solution used in the polishing method comprises a polishing solution A for rough polishing and a polishing solution B for ultrafine polishing, and is prepared by mixing a nano grinding agent, a pH regulating agent, a surfactant, a defoaming agent, a bactericide, an assistant cleaning agent and a solvent. The chemical and mechanical polishing method for the sulfur phase-change material has the advantages of high polishing efficiency and simple and feasible process; a polished surface is smooth and has no scratch; over polishing can be prevented well, so that the stability of the performance of a phase-change memory which is manufactured on the base of the inlaid structure and the good rate of products are improved, and the cost is reduced.

Description

technical field [0001] The invention relates to the technical field of microelectronic auxiliary materials and processing technology, in particular to a chemical mechanical polishing method and polishing liquid for chalcogenide phase change materials. Background technique [0002] With the rapid development of microelectronic technology and computer technology, the demand for large-capacity non-volatile memory is becoming more and more urgent. However, due to the high operating voltage, complex circuit structure, and the fact that the floating gate structure cannot be infinitely thinned, the further application of the flash memory in various fields is severely restricted. Especially when the process node enters 45nm, because the integration density cannot be further increased, the demand for new types of memory to replace the flash memory becomes more urgent. Phase-change memory has the advantages of high-speed reading, high erasable times, non-volatility, small component s...

AI Technical Summary

Problems solved by technology

However, when these polishing fluids are used to polish the phase change memory mosaic structure, the polishing fluid with too fast polishing rate is likely to cause over-polishing problems, which will greatly reduce the stability of the performance of the storage device, and in severe cases, the device will be unusable and the stored data will be lost. , causing losses to people

And the polishing liquid with too slow polishing rate will reduce the polishing efficiency, thereby increasing the production cost

To sum up, it is difficult for the above-mentioned polishing fluids to take into account the two aspects of efficiency and avoiding over-polishing in one-time polishing, because to improve the polishing efficiency, it is necessary to increase the polishing rate, so that it is difficult to accurately control the polishing end point, so it is difficult to avoid over-polishing. Appear; also to accurately control the polishing end point to avoid over-polishing will reduce the polishing rate, which obviously reduces the efficiency of polishing

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