CPC G03F 1/24 (2013.01) [G03F 1/26 (2013.01); G03F 1/52 (2013.01); G03F 1/80 (2013.01)] | 19 Claims |
1. A reflective mask blank comprising:
a substrate;
a multilayer reflective film that reflects EUV light;
a protection film that protects the multilayer reflective film; and
a phase shift film that shifts a phase of the EUV light, in this order,
wherein the phase shift film contains Ir as a main component,
a ratio (Ip/la) of a maximum value Ip of an intensity of a peak in a range of 2θ of 35 degrees to 45 degrees to an average value Ia of an intensity in a range of 2θ of 55 degrees to 60 degrees by an XRD method with a CuKα ray is 1.0 or more and 30 or less,
a refractive index n of the phase shift film to the EUV light is 0.925 or less, and
an extinction coefficient k of the phase shift film to the EUV light is 0.030 or more,
the phase shift film contains 50 at % or more of Ir and a first element X1 selected from the group consisting of O, B, C, and N, and O content being 15 at % or less, and
when a grayscale image is obtained by imaging a cross section of the phase shift film with a scanning transmission electron microscope (STEM) and a brightness profile of the grayscale image is created, skewness (Rsk) of the brightness profile is negative.
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