PHASE SHIFT MASK AND METHOD FOR MANUFACTURING PHASE SHIFT MASK
There are provided a phase shift mask having a small number of haze defects, that is, a phase shift mask capable of sufficiently suppressing occurrence of haze, and a method for manufacturing the phase shift mask. A phase shift mask ( 100 ) according to the present embodiment is a phase shift mask having a circuit pattern by application of exposure light having a wavelength of 200 nm or less, the phase shift mask including a substrate ( 11 ), a phase shift film ( 12 ) that is formed on the substrate ( 11 ) and has a circuit pattern, and a protective film ( 13 ) that is formed on an upper surface ( 12 t ) and a side surface ( 12 s ) of the phase shift film ( 12 ), in which the phase shift film ( 12 ) enables adjustment of each of phase and transmittance with respect to the exposure light to be transmitted to a predetermined extent, the protective film ( 13 ) has a refractive index n in a range of 1.2 or more and 2.6 or less with respect to the exposure light and an attenuation coefficient k in a range of 0.0 or more and 0.4 or less, and in a case where a film thickness of the phase shift film ( 12 ) is denoted by d 1 and a film thickness of the protective film ( 13 ) is denoted by d 2 , d 2 is thinner than d 1 , and d 2 is 15 nm or less.
1 . A phase shift mask having a circuit pattern by application of exposure light having a wavelength of 200 nm or less, the phase shift mask comprising:
a transparent substrate;
a phase shift film that is formed on the transparent substrate and has a circuit pattern; and
a gas permeation protective film that is formed on an upper surface and a side surface of the phase shift film,
wherein the phase shift film enables adjustment of each of phase and transmittance with respect to the exposure light to be transmitted to a predetermined extent,
the gas permeation protective film has a refractive index in a range of 1.2 or more and 2.6 or less with respect to the exposure light and an attenuation coefficient in a range of 0.0 or more and 0.4 or less, and
in a case where a film thickness of the phase shift film is denoted by d 1 and a film thickness of the gas permeation protective film is denoted by d 2 , d 2 is thinner than d 1 , and d 2 is 15 nm or less.
2 . The phase shift mask according to claim 1 ,
wherein the gas permeation protective film contains at least one selected from a hafnium metal and a hafnium compound, and
the hafnium compound contains hafnium and contains at least one selected from nitrogen, oxygen, carbon, or fluorine.
3 . The phase shift mask according to claim 1 ,
wherein the gas permeation protective film contains silicon and contains at least one selected from nitrogen, oxygen, or carbon.
4 . The phase shift mask according to claim 1 ,
wherein the gas permeation protective film contains aluminum and contains at least one selected from nitrogen, oxygen, or carbon.
5 . The phase shift mask according to claim 1 ,
wherein the phase shift film has resistance to oxygen-containing chlorine-based etching and is etchable by fluorine-based etching.
6 . The phase shift mask according to claim 1 ,
wherein the phase shift film contains silicon and contains at least one selected from a transition metal, nitrogen, oxygen, or carbon, and
the transition metal is at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, or tungsten.
7 . The phase shift mask according to claim 1 ,
wherein a ratio of a surface reflectivity of the gas permeation protective film to a surface reflectivity of the phase shift film is in a range of 0.4 or more and 1.2 or less.
8 . The phase shift mask according to claim 1 ,
wherein the gas permeation protective film is also formed on the transparent substrate.
9 . A method for manufacturing the phase shift mask according to claim 1 , the method comprising:
forming a phase shift film on the transparent substrate;
forming a light shielding film on the phase shift film;
forming a resist pattern on the light shielding film formed on the phase shift film;
forming a pattern on the light shielding film by oxygen-containing chlorine-based etching after forming the resist pattern;
forming a pattern on the phase shift film by fluorine-based etching after forming the pattern on the light shielding film;
removing the resist pattern after forming the pattern on the phase shift film;
removing the light shielding film from the phase shift film on which the pattern is formed by oxygen-containing chlorine-based etching after removing the resist pattern;
performing a defect inspection after removing the resist pattern and before removing the light shielding film or after removing the light shielding film;
correcting the light shielding film or the phase shift film at a defective portion in a case where a defect is detected in the defect inspection; and
forming the gas permeation protective film on an upper surface and a side surface of the phase shift film on which the pattern is formed after the correction.
10 . The method for manufacturing the phase shift mask according to claim 9 ,
wherein, in the forming of the gas permeation protective film, the gas permeation protective film is also formed on the transparent substrate.
11 . The phase shift mask according to claim 2 ,
wherein the phase shift film has resistance to oxygen-containing chlorine-based etching and is etchable by fluorine-based etching.
12 . The phase shift mask according to claim 3 ,
wherein the phase shift film has resistance to oxygen-containing chlorine-based etching and is etchable by fluorine-based etching.
13 . The phase shift mask according to claim 4 ,
wherein the phase shift film has resistance to oxygen-containing chlorine-based etching and is etchable by fluorine-based etching.
14 . The phase shift mask according to claim 2 ,
wherein the phase shift film contains silicon and contains at least one selected from a transition metal, nitrogen, oxygen, or carbon, and
the transition metal is at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, or tungsten.
15 . The phase shift mask according to claim 3 ,
wherein the phase shift film contains silicon and contains at least one selected from a transition metal, nitrogen, oxygen, or carbon, and
the transition metal is at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, or tungsten.
16 . The phase shift mask according to claim 4 ,
wherein the phase shift film contains silicon and contains at least one selected from a transition metal, nitrogen, oxygen, or carbon, and
the transition metal is at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, or tungsten.
17 . The phase shift mask according to claim 5 ,
wherein the phase shift film contains silicon and contains at least one selected from a transition metal, nitrogen, oxygen, or carbon, and
the transition metal is at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, or tungsten.
18 . The phase shift mask according to claim 2 ,
wherein a ratio of a surface reflectivity of the gas permeation protective film to a surface reflectivity of the phase shift film is in a range of 0.4 or more and 1.2 or less.
19 . The phase shift mask according to claim 3 ,
wherein a ratio of a surface reflectivity of the gas permeation protective film to a surface reflectivity of the phase shift film is in a range of 0.4 or more and 1.2 or less.
20 . The phase shift mask according to claim 4 ,
wherein a ratio of a surface reflectivity of the gas permeation protective film to a surface reflectivity of the phase shift film is in a range of 0.4 or more and 1.2 or less.