KR20170021193A - Phase Shift Blankmask, and Method for manufacturing the same - Google Patents

Abstract

Disclosed is a production method of a phase inversion blankmask. The blankmask has a phase inversion film on a transparent substrate, and the phase inversion film is formed by chemical vapor deposition (CVD). Accordingly, the phase inversion blankmask having a high transmittance phase inversion film more thinned by increasing the refractive index of the phase inversion film through increasing the silicon (Si) content can be produced.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a phase shift blank mask and a manufacturing method thereof,

The present invention relates to a phase inversion blank mask and a method of manufacturing the same, and more particularly, to a phase inversion blank mask capable of realizing a fine pattern of 32 nm or less, particularly 14 nm or less, and a method of manufacturing the same.

Today, in order to meet the demand for miniaturization of circuit patterns accompanied with the high integration of large-scale integrated circuits, advanced semiconductor fine processing technology is becoming a very important factor. In the case of a highly integrated circuit, the circuit wiring is miniaturized for low power and high speed operation, and a contact hole pattern for interlayer connection and a circuit arrangement for integration are increasingly required. Therefore, in order to satisfy these demands, miniaturization is also required in the manufacture of a photomask which is one of the lithography techniques, and a technique for recording a more precise circuit pattern is required.

In such a lithography technique, a binary blank mask using a light shielding film and a phase shifting blank mask using a phase reversal film have been commercialized to improve the resolution of a semiconductor circuit pattern, and a hard film and a hard mask having a light shielding film A binary blank mask for the mask (Hardmask Binary Blankmask) was developed.

Among them, the phase inversion blank mask is a mask which generates a predetermined phase difference (for example, 170 DEG to 190 DEG) between the transparent substrate and the exposure light transmitted through the phase inverting portion and uses the interference action of light, And is applied to the fabrication of semiconductor devices.

Recently, in order to realize a high resolution and to improve quality, a phase inversion blank mask which has a high transmittance without limiting the transmittance of the phase inversion film to about 6% is being studied. The high-transmittance phase reversal blank mask enhances the accuracy of the pattern by increasing the destructive interference of the pattern edge portion by setting the transmittance to about 6% or more.

The phase reversal film is generally formed of a molybdenum silicide (MoSi) compound using a sputtering method, but the molybdenum silicide (MoSi) compound phase reversal film has a low refractive index (n) and an extinction coefficient (k) Is high. Accordingly, in order to increase the transmittance of the phase reversal film, a large amount of one of nitrogen (N) and oxygen (O) is required to be added to the compound, and the thickness of the phase reversal film becomes very thick. However, as the thickness of the phase reversal film increases, the destructive interference of the pattern edge portion decreases due to the 3D effect, which makes it impossible to realize a high resolution.

Accordingly, there is a demand for a new material and a manufacturing method capable of realizing a thin film with a high transmittance.

An object of the present invention is to provide a phase inversion blank mask capable of realizing a fine pattern of 32 nm or less, particularly 14 nm or less, and a manufacturing method thereof.

According to an aspect of the present invention, there is provided a method of manufacturing a phase inversion blank mask including forming a phase inversion film on a transparent substrate, wherein the phase inversion film is formed by a chemical vapor deposition (CVD) method .

The phase reversal film is formed of one of Si, SiO, SiN, SiC, SiON, SiCO, SiCN, SiCON, MoSi, MoSiO, MoSiN, MoSiC, MoSiON, MoSiCO, MoSiCN and MoSiCON.

The phase reversal film is formed so as to have a transmittance of 5% to 40% and a reflectance of 40% or less with respect to exposure light having a wavelength of 193 nm or 248 nm.

Wherein the phase shift blank mask is formed by stacking a phase reversal film, a light shielding film, an etching stopper film, and a hard film, wherein the light shielding film is made of a metal material of chrome (Cr) or molybdenum chrome (MoCr) Wherein the etching stopper film is formed of a compound containing at least one element selected from the group consisting of nitrogen (N), oxygen (O), and carbon (C) in a metal material and the etching stopper film is formed of silicon (Si), a metal silicide, N), oxygen (O), and carbon (C).

Wherein the phase inversion blank mask is formed by sequentially stacking a phase reversal film, an etching stopper film, a light shielding film, and a hard film, wherein the light shielding film is made of Si, SiN, SiC, SiO, SiON, SiCO, SiCN, SiCON, MSi (N), oxygen (O), and carbon (C) is added to chromium (Cr), and the etching stopper film is formed of one of silicon nitride, silicon nitride, .

According to the present invention, since the refractive index of the phase reversal film is increased because the content of silicon (Si) can be increased by forming a phase reversal film by using chemical vapor deposition (CVD), a phase reversal blank having a thinner high- A mask can be manufactured.

In addition, the uniformity (uniformity), density, and defect of the phase reversal film can be improved, and a phase inversion blank mask excellent in quality can be manufactured.

Accordingly, the present invention can produce a phase inversion blank mask capable of realizing a fine pattern of 32 nm or less, particularly 14 nm or less, preferably 10 nm or less.

1 is a cross-sectional view showing a phase inversion blank mask according to a first embodiment of the present invention;
2 is a view for explaining a difference in refractive index according to a method of manufacturing a phase reversal film.
3 is a cross-sectional view showing a phase inversion blank mask according to a second embodiment of the present invention;
4 is a cross-sectional view showing a phase inversion blank mask according to a third embodiment of the present invention;

Hereinafter, the present invention will be described in detail with reference to the drawings, but it should be understood that the present invention is not limited to these embodiments. For example, And is not intended to limit the scope of the invention. Therefore, it will be understood by those skilled in the art that various modifications and other equivalent embodiments may be made by those skilled in the art. Accordingly, the true scope of protection of the present invention should be determined by the technical matters of the claims.

FIG. 1 is a cross-sectional view showing a phase inversion blank mask according to a first embodiment of the present invention, and FIG. 2 is a view for explaining a difference in refractive index according to a method of manufacturing a phase inversion film.

Referring to FIG. 1, a phase inversion blank mask 100 according to the present invention includes a transparent substrate 102, a phase reversal film 104 sequentially formed on the transparent substrate 102, a light shielding film 106, 112).

The transparent substrate 102 is made of quartz glass, synthetic quartz glass, or fluorine-doped quartz glass. The flatness of the transparent substrate 102 affects the flatness of any thin film formed on the upper side, for example, the phase reversal film 104, the light shielding film 106, etc., Is defined as a value of TIR (Total Indicated Reading), the value is controlled to be 500 nm or less, preferably 100 nm or less, in the region of 142 mm < 2 >.

The phase reversal film 104 may be formed of a material such as silicon (Si), molybdenum (Mo), tantalum (Ta), vanadium (V), cobalt (Co), nickel (Ni), zirconium (Zr), niobium ), Zinc (Zn), chromium (Cr), aluminum (Al), manganese (Mn), cadmium (Cd), magnesium (Mg), lithium (Li), selenium ) And tungsten (W), or the metal material may further include at least one light element selected from oxygen (O), nitrogen (N), and carbon (C).

The phase reversal film 104 according to the present invention is preferably composed of a material having a high refractive index, for example, a silicon (Si) compound in order to reduce the thickness of the phase reversal film with high phase reversal. The phase reversal film 104 is preferably formed of a silicon (Si) compound such as Si, SiO, SiN, SiC, SiON, SiCO, SiCN, SiCON. It may also be composed of one of molybdenum silicide (MoSi) compounds such as MoSi, MoSiO, MoSiN, MoSiC, MoSiON, MoSiCO, MoSiCN, MoSiCON.

Conventional phase reversal films are generally formed using a physical vapor deposition (PVD) method using a sputtering apparatus. However, when the phase reversal film is formed by the above-described sputtering method, there is a limitation in addition of the content of light element such as nitrogen (N), oxygen (O), carbon (C), and fluorine (F). As a result, there has been a limit in improving the optical, physical, and chemical properties of the phase reversal film including refractive index and the like due to the increase of the content of the light source.

The phase reversal film 104 according to the present invention is formed using Chemical Vapor Deposition (CVD) in order to improve physical and chemical properties as well as optical properties including refractive index enhancement. The chemical vapor deposition method is a method of forming a thin film using chemical bonding between injected reactive gases. When the chemical vapor deposition method is used, the content of silicon (Si) can be further increased and the refractive index of the phase reversal film can be increased more effectively. That is, referring to FIG. 2, when the phase reversal film 104 is formed by, for example, implanting silicon (Si) and sputtering and chemical vapor deposition, respectively, the chemical vapor deposition It can be confirmed that the refractive index of the phase reversal film is high.

When the phase reversal film 104 is formed of a compound containing at least one of oxygen (O), nitrogen (N), and carbon (C) in silicon (Si) using the chemical vapor deposition method, As the main gas, SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ A gas containing at least one of oxygen (O), nitrogen (N) and carbon (C) as auxiliary gas, for example, O ₂ , N ₂ , CO ₂ , ON, NH ₃ , CH _3, or the like can be used to form a silicon (Si) compound. At this time, the main gas has a gas flow rate of 3 vol% to 40 vol%, and the auxiliary gas has a gas flow rate of 60 vol% to 97 vol%.

In detail, when the phase reversal film 104 is composed of a silicon oxide (SiO) film, at least one of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ The gas has a gas flow rate of 3 vol% to 40 vol%, and the oxygen (O ₂ ) gas has a gas flow rate of 60 vol% to 97 vol%.

When the phase reversal film 104 is made of a silicon nitride (SiN) film, at least one main gas among SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ And the ammonia (NH ₃ ) gas has a gas flow rate ratio of 60 vol% to 95 vol%.

In addition, when the phase reversal film 104 is made of a silicon oxynitride (SiON) film, at least one of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ The gas has a gas flow rate of ₃ vol% to 20 vol%, oxygen (O ₂ ) gas of 15 vol% to 20 vol%, and ammonia (NH ₃ ) gas of 60 vol% to 82 vol%.

The phase reversal film 104 may be formed by metal-organic chemical vapor deposition (MOCVD) using various precursors, for example, in the case of containing a metal, The deposition method is not limited.

When the phase reversal film 104 is composed of molybdenum silicide (MoSi) containing oxygen (O), nitrogen (N) and carbon (C), the same process gas as the above- . ≪ / RTI >

The phase reversal film 104 has a structure of a single layer film having a uniform composition, a single layer continuous film whose composition or composition ratio continuously changes, or a multilayer film in which one or more films having different compositions or composition ratios are stacked one or more layers.

The phase reversal film 104 may be formed so as to have a structure of a continuous film or a multilayer film including oxygen (O) at the uppermost or uppermost layer, for the purpose of improving optical characteristics and improving chemical resistance. At this time, the uppermost layer or the uppermost layer has an oxygen (O) content of 0.1 at% to 20 at%, and has an oxygen (O) content higher than that of the lower or lower film. The uppermost or uppermost layer has a thickness of 2% to 30% of the thickness of the entire phase reversal film 104, and has a higher transmittance than the lower layer.

The phase reversal film 104 has a transmittance of 5% to 40% with respect to exposure light having a wavelength of 193 nm or 248 nm. If the transmittance of the phase reversal film 104 is lower than 5%, the intensity of the exposure light for the destructive interference during exposure to the resist film applied to the wafer is reduced, the phase reversal effect is insignificant, , Damage to the resist film applied to the wafer is given to increase the loss of the resist film.

The phase reversal film 104 has a thickness of 300 ANGSTROM to 750 ANGSTROM and preferably has a thickness of 500 ANGSTROM to 600 ANGSTROM and has a phase reversal amount of 170 DEG to 190 DEG relative to exposure light of 193 nm or 248 nm wavelength, % Or less, preferably 30% or less of the surface reflectance.

The phase reversal film 104 may be selectively heat-treated at 100 to 500 degrees to adjust chemical resistance and flatness.

The light shielding film 106 has a multilayer structure in which a single layer film or a light shielding film and an antireflection film are laminated and is formed of a material having an etching selectivity ratio of 10 or more as compared with the phase reversing film 104.

The light shielding film 106 may be formed of any one of molybdenum (Mo), tantalum (Ta), nickel (Ni), zirconium (Zr), niobium (Nb), palladium (Pd), zinc (Zn) Cr, Al, Mn, Cd, Mg, Li, Se, hafnium, tungsten, Or one or more light element materials selected from the group consisting of nitrogen (N), oxygen (O), carbon (C), boron (B) and hydrogen (H).

The light shielding film 106 may be made of, for example, a metal material of chrome (Cr) or molybdenum chrome (MoCr), or may be formed of one of nitrogen (N), oxygen Or more of the light element.

When the light shielding film 106 is formed of a chromium (Cr) compound, the light shielding film 106 is formed of 30 at% to 70 at% of chromium (Cr), 10 at% to 40 at% of nitrogen (N) To 50 at%, and carbon (C) is 0 to 30 at%. When the light shielding film 106 is formed of a molybdenum chromium (MoCr) compound, the light shielding film 106 may be formed by a combination of 2 at% to 30 at% of molybdenum (Mo), 30 at% to 60 at% (N) of 10 at% to 40 at%, oxygen (O) of 0 to 50 at%, and carbon (C) of 0 to 30 at%.

The light shielding film 106 may be composed of a multilayer film of two or more layers including a first light shielding layer and a second light shielding layer. Here, the first light blocking layer is formed on the phase reversing film 104 and controls the optical density (OD) of the light blocking film 106. Accordingly, the first light-shielding layer has a thickness corresponding to 70% to 99% of the total thickness of the light-shielding film 106. When the optical density of the second light-shielding layer on the first light-shielding layer is adjusted only by the first light-shielding layer, the thickness of the second light-shielding layer may be increased to match the optical characteristics required for the light- So that the optical density required for the light shielding film 106 can be supplemented. The second light shielding layer has a thickness corresponding to 1% to 30% of the thickness of the entire light shielding film 106, and the second light shielding layer has an optical characteristic with respect to an exposure wavelength per unit thickness (A) The optical density is high.

The first light-shielding layer has a large thickness of the light-shielding film 106, and therefore must have a fast etch rate in order to have a good vertical cross-sectional shape at the time of pattern formation. Accordingly, the first light-shielding layer includes at least one of oxygen (O) and nitrogen (N) to increase the etching rate. At this time, the first light-shielding layer has an oxygen (O) content of 1 at% to 50 at%, and preferably an oxygen (O) content of 10 at% to 20 at%.

The second light-shielding layer may contain a trace amount of at least one of oxygen (O), nitrogen (N), and carbon (C) in a predetermined case taking into account the etching process and sheet resistance of the film. When the second light-shielding layer contains oxygen (O), the thickness of the film may be increased, but since the etching rate is increased, the same effect can be obtained in thinning the etching time and the resist film thickness. Further, when carbon (C) is included, the sheet resistance of the light shielding film 106 can be lowered.

The light shielding film 106 has a thickness of 300 ANGSTROM to 700 ANGSTROM and preferably has a thickness of 350 ANGSTROM to 550 ANGSTROM and has an average etching rate of 0.5 ANGSTROM to 4.0 ANGSTROM / sec. The optical density of the portion where the phase reversal film 104 and the light shielding film 106 are laminated has an optical density of 2.5 to 3.5 with respect to the exposure wavelength of 193 nm or 248 nm and preferably has an optical density of 2.7 to 3.2 . The surface reflectance of the portion where the phase reversal film 104 and the light shielding film 106 are laminated is 10% to 40%, preferably 15% to 35%.

The light-shielding film 106 may be selectively heat-treated, and the heat-treatment temperature may be equal to or lower than the heat-treatment temperature of the lower phase-reversing film 104.

Further, although not shown, a hard film serving as an etching mask for the light shielding film 106 may be provided on the light shielding film 106. The hard film may further comprise silicon (Si), a metal silicide, or at least one light element material selected from the group consisting of nitrogen (N), oxygen (O), and carbon (C). The metal may be selected from the group consisting of tantalum (Ta), nickel (Ni), zirconium (Zr), niobium (Nb), palladium (Pd), zinc (Zn), tin (Sn), chromium (Cr) Mn, cadmium, magnesium, lithium, selenium, hafnium, tungsten and silicon.

The hard film 210 has an etch rate of 0.4 A / sec or more, preferably an etch rate of 1.0 A / sec or more, and a thickness of 20 to 100 angstroms.

A chemically amplified resist (CAR) is used as the resist film 114. The resist film 114 has a thickness of 400 ANGSTROM to 1500 ANGSTROM and preferably 400 ANGSTROM to 1,000 ANGSTROM.

3 is a cross-sectional view showing a phase inversion blank mask according to a second embodiment of the present invention.

3, the phase inversion blank mask 200 according to the present invention includes a transparent substrate 102, a phase reversal film 104 sequentially formed on the transparent substrate 102, a light shielding film 106, A protective film 108, a hard film 110, and a resist film 112. Here, the phase reversal film 104, the light shielding film 106, and the resist film 112 have the same optical, chemical, and physical properties as those of the first and second embodiments described above.

The etch stop film 108 is provided on the light shielding film 106 and protects the light shielding film 106 located below the hard film 110 when the hard film 110 is formed or when the hard film pattern is removed And serves as an etching mask in pattern formation of the light shielding film 106. [ Accordingly, the etch stop layer 108 is formed of a material having an etch selectivity ratio of 10 or more with respect to the hard film 110 and the light shielding film 106. The etch stop layer 108 may be formed of the same material as the phase inversion layer 104 when the etch stop layer 108 is removed during pattern formation of the phase inversion layer 104 for simplification of the etching process. have.

The etch stop layer 108 may be formed of one of silicon (Si), molybdenum (Mo), tantalum (Ta), vanadium (V), cobalt (Co), nickel (Ni), zirconium (Zr), niobium (Pd), Zn, Cr, Al, Mn, Cd, Mg, Li, Selenium, Cu, (N), oxygen (O), and carbon (C), in addition to at least one material selected from the group consisting of Hf, Hf, and W.

The etch stop layer 108 may further comprise at least one element selected from the group consisting of silicon (Si), metal silicide, or at least one elemental element of nitrogen (N), oxygen (O) Silicon (Si) compound, and metal suicide compound.

When the etching stopper film 108 is made of a silicon compound, the etching stopper film 108 is formed to have a silicon (Si) content of 40 at% to 90 at% and a light element (O, N, C) And preferably has a composition ratio of silicon (Si) of 50 at% to 85 at% and a light element (O, N, C) of 15 at% to 50 at%. In the case where the etching stopper film 108 is made of a metal silicide or a compound thereof, the etching stopper film 108 may be formed of a metal of 0.1 at% to 10 at%, a silicon (Si) of 39 at% to 85 at%, a light element of 10 at% % To 60 at%, and preferably has a composition ratio of 0.1 at% to 5 at% of metal, 50 at% to 80 at% of silicon (Si), and 15 at% to 50 at% of light element.

The etch stop layer 108 has a thickness of 20 ANGSTROM to 150 ANGSTROM, preferably 30 ANGSTROM to 100 ANGSTROM.

The hard film 110 is provided on the etch stop layer 108 to serve as an etch mask for the etch stop layer 108 so that the hard film 110 is composed of a material having an etch selectivity ratio of 10 or more to the etch stop layer 108 do. The hard film 110 is formed of a material having the same etching property as the light shielding film 106 when the light shielding film 106 is removed in patterning for simplification of the etching process.

The hard film 110 may be formed of at least one of Ta, Ni, Zr, Nb, Pd, Zn, Sn, Cr, At least one of Mn, Mn, Cd, Mg, Li, Se, Hf, W, and Si, Or one or more light element materials selected from the group consisting of nitrogen (N), oxygen (O), and carbon (C).

The hard film 110 is preferably formed of, for example, chromium (Cr) or a chromium (Cr) compound containing chromium (O, N, C) in chromium (Cr). In addition, the hard film 110 may further include tin (Sn) in the chromium (Cr) or chromium (Cr) compound to increase the etching rate.

The hard film 110 has an etching rate of 0.4 A / sec or more, and preferably has an etching rate of 1.0 A / sec or more. The higher the etch rate of the hard film 210, the easier the thinning of the resist film 212 is.

The hard film 110 has a thickness of 20 ANGSTROM to 100 ANGSTROM, preferably 30 ANGSTROM to 60 ANGSTROM. In the case where the hard film 210 has a thickness of 20 angstroms or less, it is difficult to perform the role as an etch mask. When the hard film 210 has a thickness of 100 angstroms or more, it is difficult to make the resist film 112 thin.

Although not shown, the phase inversion blank mask according to the present invention can be configured to include a transparent substrate, a phase reversal film sequentially formed on a transparent substrate, an etching stop film, a light shielding film, and a hard film. In this case, the phase reversal film and the light shielding film have the same etching property, and the light shielding film may be formed of silicon (Si), metal silicide (MSi), nitrogen (N), oxygen (O) , A silicon (Si) compound, or a metal silicide (MSi) compound further comprising at least one material. The phase reversal film has the same optical, chemical and physical characteristics as the above-mentioned phase reversal film. Here, the etch barrier serves to protect the phase reversal film during the formation of the light shielding film pattern.

The etching stopper film and the hard film have an etching characteristic different from that of the phase reversal film and the light shielding film and are formed of chromium or one or more of nitrogen (N), oxygen (O), and carbon (C) (Cr).

4 is a cross-sectional view showing a phase inversion blank mask according to a third embodiment of the present invention.

4, the phase inversion blank mask 300 according to the present invention includes a transparent substrate 102, a phase reversal film 104 sequentially formed on the transparent substrate 102, an etch stop film 108, A hard film 110, and a resist film 112, as shown in FIG. Here, the phase reversal film 104 and the hard film 110 have the same optical, chemical and physical characteristics as those of the second embodiment described above.

The etching stopper film 108 is a material having an etching selection ratio of 10 or more and preferably 20 or more to the upper light shielding film 106 and the lower phase inverting film 104 and is made of silicon (Si), molybdenum (Mo), tantalum (Ta) (V), Co, Ni, Zr, Nb, Pd, Zn, Cr, Al, Mn, And at least one material selected from the group consisting of cadmium (Cd), magnesium (Mg), lithium (Li), selenium (Se), copper (Cu), hafnium (Hf), and tungsten Is composed of a compound in which chromium (Cr) contains at least one light element selected from oxygen, nitrogen, and carbon. At this time, the etching stopper film 108 has a composition ratio of chromium (Cr): light element = 60 to 100 at%: 0 to 40 at%.

The thickness of the etching stopper film 108 is preferably 2 nm to 10 nm or less.

The etch stop layer 108 is etched to the same etch material at the time of pattern formation with the upper hard film 108 and is configured such that the etch rate is 0.2 to 5 times that of the hard film 108. [ At this time, if the etching stopper film 108 is too slow in etching rate compared to the hard film 108, the overetching time for the upper hard film 108 becomes longer and the light shielding film 106 under the hard film 108 becomes longer, It is possible to give damages to the user. On the other hand, if the etch stopping film 108 is etched at a speed five times or more faster than the upper hard film 108, a factor such as an undercut phenomenon such as an undercut phenomenon may occur at the time of etching. Therefore, the etching stopper film 108 is controlled to have an etching rate of 0.2 to 5 times, preferably 0.5 to 3 times as high as the upper hard film 108.

The light shielding film 106 may be formed of a silicon compound containing at least one selected from among metal silicide MSi, oxygen O, nitrogen N and carbon C including silicon (Si) and metal (M) Or a metal silicide (MSi) compound, for example, Si, SiN, SiC, SiO, SiON, SiCO, SiCN, SiCON, MSi, MSiN, MSiC, MSiO, MSiON, MSiCO, MSiCN, MSiCON. Or more. The metal M may be at least one selected from the group consisting of Mo, Ta, V, C, Ni, Zr, Nb, Pd, Zn, Cr, Al, Mn, Cd, Mg, Li, Selenium, Cu, Hafnium, W). Preferably, the metal (M) is molybdenum (Mo) or tantalum (Ta).

The sputtering target for forming the light shielding film 106 is made of silicon (Si) alone or a compound containing at least one of silicon (Si) and the above-mentioned metal (M). When the light shielding film 106 is formed of a silicon (Si) compound, the sputtering target uses boron (B) doped with a silicon (Si) target to have conductivity. When the light shielding film 106 includes a metal, a co-sputtering method using a target made of a metal and a silicon can be applied, and a two-component system target made of metal and silicon alloy . At this time, it is preferable that the composition ratio of the two-component system including the metal has Mo: Si = 5 at% to 20 at%: 80 at% to 15 at%.

The light shielding film 106 may have a multi-layer structure in which a single layer, a light-shielding film and an antireflection film are laminated, or a multilayer structure in which a first light-shielding layer and a second light-shielding layer are laminated. In the case of a single layer, A film, and a continuous film in which the composition ratio of the thin film changes continuously. On the other hand, when the light shielding film 106 is formed of two or more layers, for example, the reflectance can be controlled by setting the content of nitrogen (N) contained in the uppermost layer to be relatively higher than that of the lower layer.

The light blocking film 106 has an average etching rate of 0.5 to 4.0 A / sec.

On the other hand, in order to minimize the spontaneous response to the XeF2 gas during repair (e-beam repair), the difference in the nitrogen content in the depth direction of the upper and lower layers or the entire light shielding film 106 is maximum 30at%, preferably 20at% or less. Repair is performed using e-beam and XeF2 gas in the repair process of the light shielding film 106. [ If additional repair is performed on the adjacent area, damage to XeF2 gas occurs. This is generally referred to as " spontaneous reaction ", and the spontaneous reaction occurs due to the different etch rates of the upper and lower layers for XeF2. Therefore, in order to suppress the spontaneous reaction to XeF2 gas, it is preferable to set the nitrogen content of the entire upper and lower layers or the entire light shielding film 106 to 30 at% or less, preferably 20 at% or less to reduce the etching rate difference between the respective layers desirable. On the other hand, the difference in etching rate can be controlled not only by the nitrogen content but also by the content of molybdenum contained in the light shielding film 106, so that the content of molybdenum contained in the phase reversal film is 1 at% to 15 at% Spontaneous reactions may be suppressed.

The light shielding film 106 has a composition ratio of 0 at% to 15 at% of metal, 45 at% to 75 at% of silicon, and a total sum of oxygen atoms, nitrogen atoms, and carbon atoms of 10 at% to 55 at%.

When the light shielding film 106 has a multilayer structure of two or more layers, the top layer has a thickness of 2% to 30% of the total light shielding film 106 thickness.

The light shielding film 106 has a thickness of 300 ANGSTROM to 700 ANGSTROM, preferably 200 ANGSTROM to 500 ANGSTROM, and the reflectance at the surface of the light shielding film is 40% or less, preferably 35% or less.

The light shielding film 106 is formed so as to have a film stress of 500 MPa or less, preferably 200 MPa or less. When the thin film stress is defined as TIR (Total Indicated Reading), the TIR difference (phase reversal film-transparent substrate) is superior to control to 100 nm or less, preferably 50 nm or less.

In the structure in which the phase reversal film 104, the etching stopper film 108 and the light shielding film 106 are sequentially laminated, the optical density has 2.5 to 3.5 or less at an exposure wavelength of, for example, 193 nm.

The resist film 112 is formed on the hard film 108 and a chemically amplified resist (CAR) having a thickness of 40 nm to 150 nm can be formed by a spin coating method .

In addition, the phase inversion blank mask according to the present invention can use chemical vapor deposition for forming all the thin films including the light shielding film, the etching stop film, the hard film, etc. in addition to the phase reversal film. The thin films except for the phase reversing film are formed by a sputtering process May be formed by various thin film forming methods conventionally disclosed.

Hereinafter, a phase inversion blank mask according to an embodiment of the present invention will be described in detail.

(Example)

Evaluation of optical characteristics according to constituent materials of phase reversal film

In order to evaluate the phase reversal films according to the embodiments of the present invention, low pressure chemical vapor deposition (LPCVD) and sputtering methods were used to form silicon (Si) compounds, respectively, and refractive indices according to each manufacturing method and materials were evaluated.

In Example 1, a SiN film having a thickness of 630 ANGSTROM was formed by a low-pressure chemical vapor deposition method in which SiH ₄ : NH ₃ = ₄₀ sccm: 250 sccm was injected as a process gas.

In Example 2, a SiO 2 film having a thickness of 650 Å was formed by a low-pressure chemical vapor deposition method in which SiH ₄ : O ₂ = 30 sccm: 850 sccm was injected as a process gas.

In Example 3, a SiCN film having a thickness of 620 ANGSTROM was formed by a low-pressure chemical vapor deposition method in which SiH ₄ : NH ₃ : C ₃ H ₈ = ₄₀ sccm: 250 sccm: 5 sccm.

The phase reversal films in Examples 1 to 3 were formed at a process temperature of 400 and a process pressure of 200 mTorr.

In Comparative Example 1, a silicon (Si) target was used and an SiN film having a thickness of 680 ANGSTROM was formed by a sputtering method in which Ar: N ₂ = 7 sccm: 5.5 sccm was injected as a process gas and the process power was 1.0 kW.

In Comparative Example 2, a SiON film having a thickness of 730 ANGSTROM was formed by sputtering with a silicon (Si) target and a process power of 0.7 kW by injecting Ar: N ₂ : NO = 6 sccm: 2.5 sccm: .

In Examples 1 to 3 and Comparative Examples 1 and 2, after forming a phase reversal film, the phase reversal amount of the phase reversal film was measured using an n & k analyzer 3700RT apparatus, and the refractive index was measured using an Ellipsometer.

Table 1 shows the results of evaluating the refractive index of the phase reversal film and the phase inversion amount of Examples 1 to 3 and Comparative Examples 1 and 2.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Film forming device LPCVD LPCVD LPCVD DC-Sputter DC-Sputter matter SiN SiO SiCN SiN SiON Transmittance
(@ 193 nm) 35% 45% 37% 30% 33% Phase inversion amount
(@ 193 nm) 178 179 ° 179 ° 178 180 ° Refractive index (n)
(@ 193 nm) 2.62 2.25 2.64 2.40 2.0 Film thickness 630 Å 685 Å 620 A 680 Å 730 Å

Referring to Table 1, it was confirmed that Examples 1 to 3 exhibited a transmittance of 30% or more and were suitable as a constituent material of a phase reversal film having improved transmittance.

It is also confirmed that the phase reversal films of Examples 1 to 3 have a higher refractive index than the phase reversal films of Comparative Examples 1 to 2, so that the phase reversal film can be made thinner.

Comparing Example 1 and Example 3, it was confirmed that the refractive index of the phase reversal film was increased to decrease the thickness of the phase reversal film and increase the transmittance when carbon (C) was included in the silicon compound. When the phase reversal film is formed of a multilayer film of two or more layers, one layer contains nitrogen (N) to control the amount of phase reversal, and the other layer contains oxygen (O), so that the transmittance can be controlled.

While the present invention has been described with reference to the preferred embodiments, the technical scope of the present invention is not limited to the range described in the above embodiments. It will be apparent to those skilled in the art that various changes or modifications can be made to the embodiments described above. It is apparent from the description of the claims that the form of such modification or improvement can be included in the technical scope of the present invention.

100, 200: phase inversion blank mask 102: transparent substrate
104: phase reversal film 106: shielding film
108: etch stop film 110: hard film
112: resist film

Claims (29)

A method of manufacturing a phase inversion blank mask including forming a phase reversal film on a transparent substrate,
Wherein the phase reversal film is formed by a chemical vapor deposition (CVD) method.
Forming a phase reversal film on the transparent substrate;
Sequentially forming a light shielding film, an etching stopper film and a hard film on the phase reversal film; / RTI >
Wherein the phase reversal film has the same etching property as the etching stopper film and is formed by a chemical vapor deposition (CVD) method.
Forming a phase reversal film on the transparent substrate;
Sequentially forming an etching stopper film, a light shielding film, and a hard film on the phase reversal film; / RTI >
Wherein the phase reversal film has the same etching property as that of the light shielding film and is formed by a chemical vapor deposition (CVD) method.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed of one of Si, SiO, SiN, SiC, SiON, SiCO, SiCN, SiCON, MoSi, MoSiO, MoSiN, MoSiC, MoSiON, MoSiCO, MoSiCN, MoSiCON .
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is made of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ Wherein at least one of the main gas and at least one of oxygen (O), nitrogen (N), and carbon (C) is used as the auxiliary gas.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film comprises at least one of a main gas of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ in an amount of 3 vol% to 40 vol% O), nitrogen (N), and carbon (C). The method of manufacturing the phase inversion blank mask according to claim 1,
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed of a SiO 2 film, wherein the SiO 2 film contains 3 vol% to 40 vol% of at least one gas of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H _6, and SiH ₂ Cl ₂ , And the oxygen (O ₂ ) gas is injected at a gas flow rate ratio of 60 vol% to 97 vol%.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed of an SiN film, and the SiN film is formed to have a concentration of 5 vol% to 40 vol% of at least one gas of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H _6, and SiH ₂ Cl ₂ , And the oxygen (O ₂ ) gas is injected at a gas flow rate ratio of 60 vol% to 95 vol%.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed of a SiON film, and the SiON film is formed to have a concentration of 3 vol% to 30 vol% of at least one gas of SiH ₄ , SiCl ₄ , Si (C ₂ H ₅ O) ₄ , Si ₂ H ₆ and SiH ₂ Cl ₂ , oxygen (O ₂₎ gas is 15vol% ~ 20vol%, ammonia (NH ₃₎ gas phase shift mask blank manufacturing method characterized in that it is formed by injection into the gas flow ratio of 60vol% ~ 82vol%.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed to have a transmittance of 5% to 40% with respect to exposure light having a wavelength of 193 nm or 248 nm.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film has a phase inversion amount of 170 DEG to 190 DEG with respect to exposure light having a wavelength of 193 nm or 248 nm and has a reflectance of 40% or less.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed to a thickness of 400 ANGSTROM to 750 ANGSTROM.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed so as to have a structure of a single layer film having a uniform composition, a single layer continuous film whose composition or composition ratio continuously changes, or a multilayer film in which one or more films having different compositions or composition ratios are stacked one or more layers A method for fabricating a phase inversion blank mask.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed of a continuous film or a multilayer film, and the uppermost layer or the uppermost layer is formed to have an oxygen (O) content of 0.1 at% to 20 at%.
4. The method according to any one of claims 1 to 3,
Wherein the phase reversal film is formed of a continuous film or a multilayer film and the uppermost layer or the uppermost layer is formed to have a thickness of 1% to 30% of the total phase reversal film thickness.
The method according to claim 1,
And forming a light shielding film on the phase reversal film.
The method according to claim 2, 3, or 16,
Wherein the light shielding film is formed to have one of a single layer, a multilayer structure in which a light shielding film and an antireflection film are laminated, and a multilayer structure in which a first light shielding layer and a second light shielding layer are laminated.
3. The method of claim 2,
Wherein the light shielding film is made of a metal material of chrome (Cr) or molybdenum chrome (MoCr), or a compound containing at least one light element of nitrogen (N), oxygen (O) Wherein the phase shift mask is formed by patterning the phase shift mask.
3. The method of claim 2,
The light shielding film 106 is made of a molybdenum chromium (MoCr) compound, and the light shielding film 106 is made of 2 at% to 30 at% molybdenum (Mo), 30 at% to 60 at% Is formed to have a composition ratio of 10 at% to 40 at%, oxygen (0) of 0 to 50 at%, and carbon (C) of 0 to 30 at%.
The method of claim 3,
Wherein the light shielding film is formed of one of Si, SiN, SiC, SiO, SiON, SiCO, SiCN, SiCON, MSi, MSiN, MSiC, MSiO, MSiON, MSiCO, MSiCN and MSiCON.
The method according to claim 2, 3, or 16,
Wherein the light shielding film is formed to have a thickness of 300 ANGSTROM to 700 ANGSTROM.
The method according to claim 2, 3, or 16,
Wherein the light shielding film is formed so as to have an average etching rate of 0.5 A / sec to 4.0 A / sec.
3. The method of claim 2,
Wherein the etch barrier film is formed by further including silicon (Si), a metal silicide, or at least one light source material selected from the group consisting of nitrogen (N), oxygen (O), and carbon (C) A method of manufacturing a blank mask.
3. The method of claim 2,
Wherein the etching stopper film is formed to have a composition ratio of silicon (Si) of 40 at% to 90 at% and a light element of 10 at% to 60 at%.
3. The method of claim 2,
Wherein the etching stopper film is formed to have a composition ratio of 0.1 at% to 10 at% of metal, 39 at% to 85 at% of silicon (Si), and 10 at% to 60 at% of light element.
The method of claim 3,
The etching stopper film is formed by further including at least one element selected from the group consisting of nitrogen (N), oxygen (O) and carbon (C) in chromium (Cr) Wherein the composition is formed to have a composition ratio of 0 to 40 at%.
The method of claim 3,
Wherein the etching stopper film has the same etching property as that of the hard film, and the etching stopper film is formed to have an etching rate of 0.2 to 5 times that of the hard film.
The method according to claim 2 or 3,
Wherein the etch stop layer is formed to have a thickness of 20 ANGSTROM to 150 ANGSTROM.
A phase inversion blank mask fabricated using the phase inversion blank mask manufacturing method of any one of claims 1 to 3.

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