Chemical mechanical polishing solution

Abstract

The present invention discloses a chemical-mechanical polishing liquid comprising abrasive particles, oxidant and water. The liquid further comprises at least one inorganic salt for improving the removal rate of silicon dioxide, and at least one azoles-containing compound for increasing the removal rate of low-k materials. The salt and the compound have synergistic reaction. The chemical-mechanical polishing liquid according to the present invention can perform chemical-mechanical polishing of copper barrier layer at low stress, and has higher remove rate of dielectric material, and also has lower solid content.

Description

technical field [0001] The invention relates to a polishing liquid, in particular to a chemical mechanical polishing liquid. Background technique [0002] In 130nm and more advanced processes, the use of copper metal as interconnection lines can reduce resistance, thereby greatly reducing transmission delay (RC delay), and at the same time, the use of low dielectric materials (Low-k materials) also further weakens Parasitic capacitance, such as carbon-doped silicon oxide (CDO) compared with PETEOS, the capacitance is reduced by about 30%. In addition, due to the relatively weak mechanical properties of low-k materials, a silicon-based capping film such as silicon dioxide dielectric material (PETEOS), SiON, etc. is usually deposited on it to ensure that the medium is The material is free from chipping and corrosion to maintain its mechanical properties and dielectric constant. In this way, the CMP process requires rapid removal of the capping layer and part of the dielectri...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to overcome the high solid content of the existing chemical mechanical polishing liquid, which needs to be carried out under higher stress when polishing, for low dielectric materials (Low-k materials) and silicon oxide (PETEOS ) chemical removal is difficult, and it is easy to cause defects such as corrosion of metal and dielectric materials, and provides a chemical method that can chemically polish the copper barrier layer under low stress and has a higher removal rate of dielectric materials Mechanical polishing fluids, which can also have a lower solids content

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