Mask blank for EUV exposure and mask for EUV exposure
View Patent ↗Provided are a mask for EUV exposure and a mask blank for EUV exposure for manufacturing the same, so as to improve the contrast of ultraviolet inspection light and improve the inspection performance for the mask. This mask blank for EUV exposure includes a substrate, a reflecting layer which is provided on the substrate and reflects EUV light, and an absorbent layer which is provided on the reflecting layer and absorbs EUV light. Reflectance of light at a wavelength between 150 nm and 300 nm is greater at the absorbent layer than that of the reflecting layer. The mask for EUV exposure can be manufactured by processing this mask blank for EUV exposure.
1. A mask blank for EUV exposure comprising:
a substrate;
a reflecting layer which is provided on the substrate and reflects EUV light, the reflecting layer including a two-layer structure of a multi-reflecting film and a capping film formed on the multi-reflecting film; and
an absorbent layer which is provided on the reflecting layer and absorbs EUV light, the absorbing layer including a buffer film, an absorbent film formed on the buffer film, and a reflecting film that reflects inspection light formed on the absorbent film; and
wherein
the multi-reflecting film includes about 40 pairs of alternately laminated Mo films having a thickness of about 2.8 nm and Si films having a thickness of about 4.2 nm,
the capping film is TiO 2 film having a thickness of about 20 nm,
the buffer film is a CrN film having a thickness of about 10 nm,
the absorbent layer is a TaSi film having a thickness of about 70 nm, and
the reflecting film is a Cr film having a thickness of about 20 nm.
2. A mask for EUV exposure comprising:
a substrate;
a reflecting layer which is provided on the substrate and reflects EUV light, the reflecting layer including a two-layer structure of a multi-reflecting film and a capping film formed on the multi-reflecting film; and
an absorbent layer which is provided on the reflecting layer and has a predetermined pattern for absorbing EUV light, the absorbing layer including a buffer film, an absorbent film formed on the buffer film, and a reflecting film that reflects inspection light formed on the absorbent film; and
wherein
the multi-reflecting film includes about 40 pairs of alternately laminated Mo films having thickness of about 2.8 nm and Si films having thickness of about 4.2 nm,
the capping film is TiO 2 film having a thickness of about 20 nm,
the buffer film is a CrN film having a thickness of about 10 nm,
the absorbent film is a TaSi film having a thickness of about 70 nm, and
the reflecting film is a Cr film having a thickness of about 20 nm.
3. The mask according to claim 2 , wherein
a minimum half pitch of a line and a space is equal to or lower than 0.3 μm in the predetermined pattern.