A hardmask with increasing oxygen content

Abstract

The invention relates to a hard mask with gradually-increased oxygen content. A method for manufacturing the hard mask includes the following steps that: a) a dense film layer is deposited on a semiconductor substrate through utilizing a processing gas containing OMCTS; and b) an oxygen-containing thin film layer is deposited through utilizing a processing gas containing OMCTS and O2, wherein the oxygen content of the oxygen-containing thin film layer is gradually increased. With the method of the invention adopted, undercut phenomena in an etching profile can be effectively improved.

Description

technical field [0001] The present invention relates to a masking process in a semiconductor manufacturing process, more specifically, the present invention relates to a hard mask with increasing oxygen content and a manufacturing method thereof. The hard mask can effectively improve the undercut phenomenon in an etching profile. Background technique [0002] In the field of semiconductor technology, the masking process is an important part of patterning on the substrate. Generally, masks can be classified into soft masks and hard masks. Soft mask usually refers to photoresist material, namely photoresist. The hard mask is a mask structure obtained after etching the dielectric material layer. After the hard mask is formed, the subsequent process is to etch the underlying structure of the hard mask to form structures such as trenches, via holes, and gaps. [0003] In the context of semiconductor technology, low-k (low-k) materials generally refer to materials with a dielec...

AI Technical Summary

Problems solved by technology

[0005] The inventor found in practice that, Figure 1A One of the problems faced by the TEOS-based hard mask illustrated in is that in the subsequent wet etching process, it will be found that there is a relatively serious undercut phenomenon between the porous low-k film 102 and the TEOS film 104

Therefore, the selectivity of the wet etching process on the TEOS thin film layer is poor, resulting in more lateral etching, forming an undercut area on the etching profile

[0006] The undercut phenomenon described above leads to many unfavorable results

Subsequent PVD (Physical Vapor Deposition) and ECP (Electroplating) processes may not be able to apply material well to the undercut due to the presence of the undercut, leaving voids in the relevant area

Foreseeable negative results also include: easy peeling off of hardmask, poor barrier / seed layer coverage

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