Silicon nitride layer etching composition

Abstract

Provided is a silicon nitride layer etching composition, and more specifically, a silicon nitride layer etching composition including two different silicon-based compounds in an etching composition tobe capable of selectively etching a silicon nitride layer relative to a silicon oxide layer with a remarkable etch selectivity ratio and providing remarkable effects of suppressing generation of precipitates and reducing the abnormal growth of other layers existing in the vicinity, including the silicon oxide layer when the silicon nitride layer etching composition is used for an etching processand a semiconductor manufacturing process.

Description

Technical field [0001] The present invention relates to a silicon nitride film etching composition, and more specifically, to a silicon nitride film etching composition by including two different silicon-based compounds in the etching composition, thereby being able to etch nitrogen at a higher selective ratio than silicon oxide films. An etching composition for a silicon nitride film of a silicon oxide film, a method for etching a silicon nitride film using the etching composition, a method for suppressing abnormal growth of a silicon oxide film, and a method for manufacturing a semiconductor device. Background technique [0002] Silicon oxide film (SiO 2 ) And silicon nitride film (SiN x ) Is a representative insulating film used in the semiconductor manufacturing process. Among them, the silicon nitride film is used as a cap layer, a spacer layer, or a hard mask layer in a semiconductor device. The silicon oxide film and the silicon nitride film are used alone, or one or more...

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Problems solved by technology

However, there are problems in that even a small change in the amount of pure water to be supplied will cause failure in removing the silicon nitride film, and phosphoric acid itself is a strong acid and is corrosive, so it is difficult to handle.

However, the above-mentioned silicon nitride film etching composition has the following problems: a precipitate is generated during etching, and the problem of anomalous growth (anomalous growth) in which the thickness of the silicon oxide film is increased on the contrary occurs, so it is difficult to apply it to the process.

[0005] In addition, a method of controlling the etching selectivity by using a silicon compound containing oxygen atoms directly bonded to silicon can be used, but the etching selectivity of the silicon nitride film to the silicon oxide film is not high, and the silicon nitride film Silicic acid generated during etching still induces abnormal growth, causing problems in subsequent processes

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