Phase shift blankmask and photomask for EUV lithography
AssigneeS&S TECH Co., Ltd.
InventorsYong-Dae Kim, Chul-Kyu Yang, Mi-Kyung Woo
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Abstract
Disclosed is a blankmask for EUV lithography, including a reflective film, a capping film, an etch stop film, a phase shift film, and a hard mask film which are sequentially formed on a substrate. The phase shift film contains ruthenium (Ru), and the etch stop film contains chrome (Cr) and niobium (Nb). In the etch stop film, the content of niobium (Nb) ranges from 20 to 50 at %, and the content of chrome (Cr) ranges from 10 to 40 at %. The hard mask film contains tantalum (Ta) and oxygen (O). The content of tantalum (Ta) in the hard mask film is higher than or equal to 50 at %. With the blankmask, it is possible to implement a high resolution and NILS during wafer printing, and implement DtC.
Claims9
A blankmask for extreme ultraviolet (EUV) lithography, comprising a substrate, a reflective film formed on the substrate, a capping film formed on the reflective film, an etch stop film formed on the capping film, a phase shift film formed on the etch stop film, and a hard mask film formed on the phase shift film, wherein
- the phase shift film consisting of ruthenium (Ru), oxygen (O), and nitrogen (N) or ruthenium (Ru) and nitrogen (N), and
- the etch stop film containing chrome (Cr), niobium (Nb), and nitrogen (N), wherein content of niobium (Nb) ranges from 20 to 50 at %, content of chrome (Cr) ranges from 10 to 40 at %, and content of nitrogen (N) in the etch stop film ranges from 10 to 70 at %, and
- the hard mask film contains tantalum (Ta) and oxygen (O).
Dependencies are inferred from the claim text.