Reflective mask blank and reflective mask
A reflective mask blank includes, on/above a substrate in the following order from the substrate side a multilayer reflective film which reflects EUV light and an absorber film which absorbs EUV light. The absorber film is a tantalum-based material film containing a tantalum-based material. The absorber film provides a peak derived from the tantalum-based material in an X-ray diffraction pattern, the peak having a peak diffraction angle (2θ) of 36.8 degrees or more and a full width at half maximum of 1.5 degrees or more.
1. A reflective mask blank comprising, on/above a substrate in the following order from the substrate side:
a multilayer reflective film which reflects EUV light; and
an absorber film which absorbs FUN light,
wherein the absorber film is a tantalum-based material film comprising a tantalum-based material, where the tantalum-based material film comprises 0.05 at % or more of Krypton atoms and 10.0 at % to 18.0 at % of nitrogen atoms, and
wherein the absorber film provides a peak derived from the tantalum-based material in an X-ray diffraction pattern, the peak having a peak diffraction angle (2θ) of 36.8 degrees or more and a full width at half maximum of 1.5 degrees or more.
2. The reflective mask blank according to claim 1 , wherein the tantalum-based material film comprises 11.0 at % to 16.0 at % of nitrogen atoms.
3. The reflective mask blank according to claim 2 , comprising a protective film on the multilayer reflective film, wherein etching selectivity between the absorber film and the protective film is 45 or more in a dry etching process with a chlorine gas.
4. The reflective mask blank according to claim 3 , wherein the protective film is a ruthenium-based material film comprising a ruthenium-based material.
5. A reflective mask obtained by forming a pattern in the absorber film of the reflective mask blank accordion to claim 3 .
6. A reflective mask obtained by forming a pattern in the absorber film of the reflective mask blank according to claim 2 .
7. The reflective mask blank according to claim 1 , comprising a protective film on the multilayer reflective film, wherein etching selectivity between the absorber film and the protective film is 45 or more in a div etching process with a chlorine gas.
8. The reflective mask blank according to claim 7 , wherein the protective film is a ruthenium-based material film comprising a ruthenium-based material.
9. A reflective mast obtained by forming a pattern in the absorber film of the reflective mask blank according to claim 7 .
10. A reflective mask obtained by forming a pattern in the absorber film of the reflective mask blank according to claim 1 .