Etching liquid composition and etching method

Abstract

The invention discloses an etching liquid composition, and the etching liquid composition is used for the etching of multiple copper-contained and molybdenum-contained films. The etching liquid composition contains hydrogen peroxide, a first organic acid or other salts thereof, a second organic acid or other salts thereof, and alcoholamine. The chelation constant of the first organic acid and copper is greater than or equal to zero and less than six. On the basis that the weight percentage of the etching liquid composition is 100, the weight percentage of the first organic acid is from 5.5 to 17.5. The chelation constant of the second organic acid and copper is greater than or equal to 6 and less than 18.5. The alcoholamine contains one or more amidogens and one or more hydroxide radicals. Therefore, the etching liquid composition is used for the etching of multiple copper-contained and molybdenum-contained films, thereby facilitating the reduction of metal residuals.

Description

technical field [0001] The present invention relates to an etchant composition, and in particular to an etchant composition for etching copper-containing and molybdenum-containing multilayer films. Background technique [0002] The wiring materials of small and medium-sized liquid crystal displays are currently mainly made of aluminum or aluminum alloy. With the development of large-sized panels, the display needs lower RC delay, shorter charging time, and lower aperture ratio. Therefore, copper and its alloys with high conductivity and better resistance to electromigration are sought for wiring materials. [0003] The manufacturing method of copper-containing wiring is to deposit a multi-layer film containing copper on the substrate, and use photoresist as a mask to determine the required circuit pattern, and then perform anisotropic etching by wet etching. The aforementioned multilayer films often use multilayer metal films containing copper and molybdenum, such as copper...

AI Technical Summary

Problems solved by technology

[0005] However, when using an etching solution containing hydrogen peroxide to etch a multilayer metal film containing both copper and molybdenum, the etching conditions required for copper and molybdenum are different. For example, the pH of etching copper is preferably 2-4, The pH for etching molybdenum is preferably 4-7, so when the etching is carried out at a pH of 2-4, it is easy to cause molybdenum residues, and when the etching is carried out at a pH of 4-7, the etching rate of copper will be too low

In order to improve the phenomenon of molybdenum residue, it has been seen to add fluorine-containing acid or organic base compound to the etching solution. However, fluorine-containing acid is corrosive to the silicon-containing layer and is not conducive to the process. Some organic base compounds such as diethylaminopropylamine (Diethylaminopropylamine, DEAPA), propylenediamine, and ammonia water have no effect, and even some organic alkali compounds will increase the current value of the etchant plus Vani to cause chamfering, or reduce the solubility of the metal and cause small particles to remain

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