Polishing liquid for CMP process and polishing method

Abstract

The invention discloses a grinding liquid for a CMP method, which is characterized in that it contains grinding materials, aqueous solvents and additives, and contains at least 15% by weight of grinding material particles with a particle diameter of 20-80nm based on the weight of the grinding liquid; The grinding method of grinding is suitable for the flattening process of the surface of the device wafer on which at least the silicon oxide film is formed, and can effectively and stably exhibit superior grinding characteristics such as flattening characteristics, low defect characteristics and high cleaning characteristics, the most suitable It is the planarization process of the surface of semiconductor devices including interlayer insulating film or element separation film, magnetic head and substrate for liquid crystal display in the semiconductor industry.

Description

technical field [0001] The present invention relates to a polishing liquid for a CMP method, more particularly, to a polishing liquid for a CMP method in the manufacture of semiconductor devices, in particular, to a step for planarizing an interlayer insulating film, for forming a shallow trench in a trench for element separation, The polishing liquid for CMP method used in the step of burying the capacitor and the metal wiring, and the step of forming the magnetic head. Background technique [0002] In the CMP method, in order to improve the flatness after polishing, a technique of using a high molecular anionic surfactant for polishing liquid is conventionally known (Japanese Unexamined Patent Publication No. 2001-57353). For this technique, the active agent interacts with the device wafer and / or abrasive material prior to grinding, and the grinding is performed by this interaction above a certain grinding pressure. The grinding pressure is relatively difficult to apply t...

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Problems solved by technology

[0004] However, in this method, high grinding pressure is not used for grinding, so many defects remain on the wafer after grinding, which will significantly damage the yield of device wafers

[0005] Similarly, the problem is that when the high-molecular anionic surfactant is mixed with the grinding fluid, it is easy to cause the agglomeration of the abrasive material, resulting in deviations in the grinding characteristics; the high-molecular anionic surfactant is still easy to remain on the surface of the workpiece even after being washed. Therefore, there is no improvement in the qualified product rate of the device wafer; the two liquids, the polymer anionic surfactant and the grinding material, must be mixed immediately before grinding, so the workability is low; etc.