MASK BLANK AND MANUFACTURING METHOD FOR MASK

Abstract

To provide a mask blank to be used for manufacturing a permeation type mask or a reflection type mask, the mask blank capable of forming a fine pattern without elimination of a resist pattern during an image development of a resist film, even if the pattern is with a high aspect ratio, and a manufacturing method of a permeation type mask or a reflection type mask using the mask blank.SOLUTION: A mask blank 10 to be used for manufacturing a permeation type mask includes: a substrate 11; a light-shielding film 12 having a resistance against oxygen-containing chlorine-based gas etching, the light-shielding film that can be etched by a fluorine-based gas or a non oxygen-containing chlorine-based gas; and a hard mask 13 having a resistance against fluorine-based gas or non oxygen-containing chlorine-based gas etching, the hard mask that can be etched by an oxygen-containing chlorine-based gas. The hard mask 13 at least includes one or more kinds of metal elements selected from titanium, zirconium, niobium, hafnium, beryllium, aluminum, indium and tin.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a mask blank used in the manufacture of a transmissive or reflective mask used in the manufacture of LSIs (large scale integrated circuits) and the like, and to a method for manufacturing a transmissive or reflective mask using the mask blank. [Background technology]

[0002] In recent years, the increasing integration of LSIs has led to an increasing demand for thinner wiring patterns that make up LSI circuits and finer contact hole patterns for wiring between layers that make up cells. LSI manufacturing uses a processing technique called photolithography, which applies a photo development technique, and the circuit pattern of the LSI is obtained by exposing a silicon wafer substrate to a laser with the desired wavelength through a photomask.

[0003] A photomask is an original plate for the circuit pattern of an LSI drawn on a substrate, and in order to form a highly accurate LSI circuit pattern, a photomask with a fine pattern that is faithful to the design is required.The projection optical system differs depending on the wavelength of the laser used in photolithography; a transmissive optical system is used for ArF light (wavelength 193 nm), and a reflective optical system is used for EUV light (Extreme Ultraviolet Light, wavelength 13.5 nm), and the photomask type can be either a transmissive or reflective type depending on the projection optical system.

[0004] Here, the photomask pattern is produced by forming a resist film by spin coating or the like on a laminated substrate, called a blank (mask blank), on which thin films such as a light-shielding film and an absorbing film have been formed, and then performing electron beam drawing and development to create a resist pattern. Using the resist pattern as a mask, the thin film is etched to obtain a thin film pattern. It is known that problems occur in the conventional technology, such as the inability to form a fine pattern because a fine resist pattern disappears when developing a resist film, or the inability to form a pattern faithful to the design because the etching speed varies within the photomask surface depending on the density difference of the thin film pattern when etching a thin film. Therefore, various methods for solving these problems have been investigated.

[0005] For example, in order to suppress the variation in pattern dimensions depending on the density difference of the pattern that occurs during etching of the light-shielding film, there is a method of using a light-shielding film mainly composed of tantalum or silicon that can be etched by fluorine-based gas or oxygen-free chlorine-based gas instead of a light-shielding film mainly composed of chromium that can be etched by oxygen-containing chlorine-based gas, which is widely used as a light-shielding film for binary masks and halftone phase shift masks (see Patent Document 1). Since etching with oxygen-containing chlorine-based gas is highly isotropic, the light-shielding film mainly composed of chromium generates variation in the pattern dimensions within the photomask surface depending on the density difference of the pattern due to the loading effect. On the other hand, since etching with fluorine-based gas or oxygen-free chlorine-based gas is highly anisotropic, the light-shielding film mainly composed of tantalum or silicon is less susceptible to the density difference of the pattern compared to the light-shielding film mainly composed of chromium, and can be processed faithfully to the design.

[0006] Furthermore, for example, there is a method of providing a hard mask between the resist film and the light-shielding film in order to prevent the fine resist pattern from disappearing during development of the resist film (see Patent Document 2). When a hard mask is provided, the photomask pattern is produced by obtaining a resist pattern, etching the hard mask using the resist pattern as a mask to form a hard mask pattern, and then etching the light-shielding film using the hard mask pattern as a mask to obtain a light-shielding film pattern. By providing a hard mask, it is possible to thin the resist film, and the aspect ratio (pattern height ÷ pattern width) of the resist pattern becomes small, thereby relaxing the surface tension during development of the resist film and preventing the disappearance of the fine resist pattern. In addition, when a hard mask is provided, the hard mask needs to function as a mask when etching the light-shielding film, and therefore needs to have resistance to the etching conditions of the light-shielding film. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4883278 [Patent Document 2] Patent No. 4989800 Summary of the Invention [Problem to be solved by the invention]

[0008] From the above, in order to obtain a photomask in which the variation in pattern dimensions depending on the difference in pattern density is suppressed and the fine resist pattern is not lost during development, it is effective to provide a hard mask mainly composed of a material that is resistant to etching with a fluorine-based gas or an oxygen-free chlorine-based gas on a light-shielding film mainly composed of tantalum or silicon that can be etched with a fluorine-based gas or an oxygen-free chlorine-based gas. However, when a hard mask is provided on a light-shielding film that can be etched by a fluorine-based gas, a hard mask mainly made of chromium is often used, but although the hard mask mainly made of chromium has sufficient resistance to etching with a fluorine-based gas or an oxygen-free chlorine-based gas, many of them do not have sufficient adhesion to a resist pattern. Therefore, a developer enters between the resist pattern and the hard mask during development, and the resist pattern is easily lost. In particular, when the aspect ratio of the resist pattern becomes high, the resist pattern is even more easily lost, which is a problem.

[0009] The present invention has been made in view of the above circumstances, and has an object to provide a mask blank for use in the manufacture of a transmission mask or a reflective mask, which is capable of forming a fine pattern even if the pattern has a high aspect ratio and in which the resist pattern does not disappear during development of the resist film, and a method for manufacturing a transmission mask or a reflective mask using the mask blank. [Means for solving the problem]

[0010] The present invention has been made to solve the above-mentioned problems, and a mask blank used in manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention comprises a substrate, a thin film formed on the substrate, which is resistant to oxygen-containing chlorine-based gas etching and can be etched by a fluorine-based gas or an oxygen-free chlorine-based gas, and a hard mask formed on the thin film, which is resistant to fluorine-based gas or oxygen-free chlorine-based gas etching and can be etched by an oxygen-containing chlorine-based gas, and the hard mask contains at least one or more metal elements selected from titanium, zirconium, niobium, hafnium, beryllium, aluminum, indium, and tin.

[0011] In addition, in a mask blank used for manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the hard mask may be composed of a plurality of layers, have an adhesion layer containing the metal element on at least the outermost surface, and have a lower layer, located closer to the substrate than the adhesion layer, that has a higher resistance to etching with a fluorine-based gas or an oxygen-free chlorine-based gas than the adhesion layer.

[0012] In addition, in a mask blank used for manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the hard mask may be composed of a plurality of layers, have an adhesion layer containing the metal element on at least the outermost surface, and have a lower layer containing chromium on the substrate side of the adhesion layer.

[0013] In the mask blank used in manufacturing a transmission mask or a reflective mask according to one aspect of the present invention, the adhesion layer may have a film thickness in the range of 1 nm to 10 nm.

[0014] In the mask blank used in manufacturing a transmission mask or a reflective mask according to one aspect of the present invention, the lower layer may have a film thickness within a range of 1 nm to 19 nm.

[0015] In the mask blank used in manufacturing a transmission mask or a reflective mask according to one aspect of the present invention, the hard mask may have a film thickness in the range of 2 nm to 20 nm.

[0016] In addition, in a mask blank used in manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the thin film may contain at least one compound selected from a silicon compound, a tantalum compound, an indium compound, and a tin compound.

[0017] In addition, in the mask blank used in manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the silicon compound may contain silicon and one or more elements selected from nitrogen, boron, oxygen, carbon, and molybdenum.

[0018] In the mask blank used in manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the tantalum compound may contain tantalum and one or more elements selected from silicon, nitrogen, boron, oxygen, carbon, and molybdenum.

[0019] In addition, in the mask blank used in manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the indium compound may contain indium and one or more elements selected from nitrogen, boron, oxygen, and carbon.

[0020] In addition, in the mask blank used in manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the tin compound may contain tin and one or more elements selected from nitrogen, boron, oxygen, and carbon.

[0021] In addition, in a mask blank used for manufacturing a transmission mask or a reflective mask according to an embodiment of the present invention, the mask blank is a transmission mask blank used for manufacturing a transmission mask, and the thin film may be a light-shielding film having a light-shielding property of an optical density of 1 or more for light with a wavelength of 193 nm.

[0022] In addition, in a mask blank used for manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the mask blank is a transmission mask blank used for manufacturing a transmission mask, and may have a semi-transparent film between the substrate and the light-shielding film, the semi-transparent film having resistance to oxygen-containing chlorine-based gas etching, being etchable by a fluorine-based gas or an oxygen-free chlorine-based gas, and inverting the phase difference of light with a wavelength of 193 nm by a desired amount.

[0023] In addition, in a mask blank used for manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the mask blank is a transmission mask blank used for manufacturing a transmission mask, and may have a protective film between the substrate and the thin film, the protective film having resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and capable of being etched by an oxygen-containing chlorine-based gas or an oxygen-based gas.

[0024] In addition, in a mask blank used for manufacturing a transmissive mask or a reflective mask according to one embodiment of the present invention, the mask blank is a transmissive mask blank used for manufacturing a transmissive mask, and the protective film may contain one or more elements selected from chromium, ruthenium, niobium, and aluminum.

[0025] In addition, in a mask blank used for manufacturing a transmissive mask or a reflective mask according to one embodiment of the present invention, the mask blank may be a reflective mask blank used for manufacturing a reflective mask, the thin film may be an absorbing film that absorbs light with a wavelength of 13.5 nm, and a multilayer reflective film having a multilayer structure and reflecting light with a wavelength of 13.5 nm may be provided between the substrate and the absorbing film.

[0026] Moreover, a manufacturing method of a transmission mask or a reflective mask according to one aspect of the present invention is a manufacturing method of a transmission mask or a reflective mask using the above-mentioned mask blank, comprising the steps of forming a resist pattern on the hard mask of the mask blank, etching the hard mask with an oxygen-containing chlorine-based gas using the resist pattern as a mask to form the hard mask pattern, and etching the thin film with a fluorine-based gas or an oxygen-free chlorine-based gas using the hard mask pattern as a mask to form a thin film pattern. Effect of the Invention

[0027] Compared to chromium, the surface free energy of the metal elements contained in the hard mask is low. Therefore, in the mask blank used for manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, the adhesion between the resist pattern and the hard mask is improved compared to conventionally used hard masks containing chromium as a main component, the developer is less likely to penetrate into the interface between the resist pattern and the hard mask during development of the resist film, and even if the pattern has a high aspect ratio, the resist pattern does not disappear during development, so that a fine pattern can be formed. Therefore, with the mask blank used for manufacturing a transmission mask or a reflective mask according to one embodiment of the present invention, and the method for manufacturing a transmission mask or a reflective mask using the mask blank, it is possible to provide a mask blank used for manufacturing a transmission mask or a reflective mask capable of forming a fine pattern, even if the pattern has a high aspect ratio, without the resist pattern disappearing during development of the resist film, and a method for manufacturing a transmission mask or a reflective mask using the mask blank. [Brief description of the drawings]

[0028] [Figure 1] 1 is a schematic cross-sectional view showing a structure of a transmission mask blank according to a first embodiment of the present invention. [Diagram 2] FIG. 4 is a schematic cross-sectional view showing a structure of a transmission mask blank according to a second embodiment of the present invention. [Diagram 3] FIG. 11 is a schematic cross-sectional view showing the structure of a transmission mask blank according to a third embodiment of the present invention. [Figure 4] FIG. 11 is a schematic cross-sectional view showing the structure of a reflective mask blank according to a fourth embodiment of the present invention. [Diagram 5] 1A to 1C are schematic cross-sectional views sequentially showing a manufacturing process of a transmission mask using the transmission mask blank according to the first embodiment of the present invention. [Figure 6] 10A to 10C are schematic cross-sectional views sequentially showing a manufacturing process of a transmission mask using a transmission mask blank according to a second embodiment of the present invention. [Figure 7]10A to 10C are schematic cross-sectional views sequentially showing a manufacturing process of a transmission mask using a transmission mask blank according to a third embodiment of the present invention. [Figure 8] 10A to 10C are schematic cross-sectional views sequentially showing the manufacturing process of a reflective mask using a reflective mask blank according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the schematic cross-sectional views do not accurately reflect the actual dimensional ratio or the number of patterns, and the amount of engraving in the transparent substrate and the amount of damage to the film are omitted. Suitable embodiments of the transmission mask blank and the reflective mask blank of the present invention include the following four forms.

[0030] (Overall configuration of mask blank) Fig. 1 is a schematic cross-sectional view showing the structure of a transmission mask blank according to a first embodiment of the present invention. A transmission mask blank 10 shown in Fig. 1 includes a substrate 11 transparent to the exposure wavelength, a light-shielding film 12 formed on the substrate 11, and a hard mask 13 formed on the light-shielding film 12. 2 is a schematic cross-sectional view showing a structure of a transmission mask blank according to a second embodiment of the present invention. A transmission mask blank 20 shown in FIG. 2 includes a substrate 21 transparent to the exposure wavelength, a semi-transparent film 24 formed on the substrate 21, a protective film 25 formed on the semi-transparent film 24, a light-shielding film 22 formed on the protective film 25, and a hard mask 23 formed on the light-shielding film 22.

[0031] Next, Fig. 3 is a schematic cross-sectional view showing the structure of a transmission mask blank according to a third embodiment of the present invention. The transmission mask blank 30 shown in Fig. 3 includes a substrate 31 transparent to the exposure wavelength, a protective film 35 formed on the substrate 31, a semi-transparent film 34 formed on the protective film 35, a light-shielding film 32 formed on the semi-transparent film 34, and a hard mask 33 formed on the light-shielding film 32, and the hard mask 33 includes a lower layer 33a formed on the light-shielding film 32, and an adhesive layer 33b formed on the lower layer 33a.

[0032] Next, Fig. 4 is a schematic cross-sectional view showing the structure of a reflective mask blank according to a fourth embodiment of the present invention. The reflective mask blank 40 shown in Fig. 4 includes a substrate 41 having small thermal expansion due to exposure, a multilayer reflective film 44 formed on the substrate 41, a protective film 45 formed on the multilayer reflective film 44, an absorbing film 42 formed on the protective film 45, and a hard mask 43 formed on the absorbing film 42. The hard mask 43 includes a lower layer 43a formed on the absorbing film 42, and an adhesive layer 43b formed on the lower layer 43a. Hereinafter, each layer constituting each mask blank according to the first to fourth embodiments of the present invention will be described.

[0033] (substrate) In this embodiment, there is no particular limitation on the substrates 11, 21, 31 that are transparent to the exposure wavelength, and for example, a synthetic quartz substrate, CaF2, aluminosilicate glass, etc. can be used. In addition, there is no particular limitation on the substrate 41 that has small thermal expansion due to exposure, and for example, a flat Si substrate, a synthetic quartz substrate, or low thermal expansion glass with added titanium can be used.

[0034] (Light-shielding film) The light-shielding films 12, 22, and 32 are thin films having a light-shielding property of an optical density of 1 or more for light with a wavelength of 193 nm. The light-shielding films 12, 22, and 32 are, for example, a single layer film made of one or more compounds selected from a silicon compound and a tantalum compound, or a mixed film or a multilayer film of these compounds. Specifically, the light-shielding films 12, 22, and 32 made of a silicon compound are a single layer film containing silicon and one or more elements selected from nitrogen, boron, oxygen, carbon, and molybdenum, or a multilayer film or a gradient film thereof. Also, the light-shielding films 12, 22, and 32 made of a tantalum compound are a single layer film containing tantalum and one or more elements selected from silicon, nitrogen, boron, oxygen, carbon, and molybdenum, or a multilayer film or a gradient film thereof.

[0035] The silicon compound may contain silicon in an amount of 10 atomic % or more and 95 atomic % or less, more preferably 30 atomic % or more and 80 atomic % or less, and even more preferably 35 atomic % or more and 70 atomic % or less, based on the element ratio of the entire silicon compound. If the silicon content is within the above numerical range, the light blocking property is further improved. The tantalum compound may contain tantalum in an element ratio of the entire tantalum compound in a range of 10 atomic % to 95 atomic % or less, more preferably in a range of 50 atomic % to 90 atomic % or less, and even more preferably in a range of 60 atomic % to 80 atomic % or less. If the above-mentioned tantalum content is within the above numerical range, the light-shielding property is further improved.

[0036] The thickness of the light-shielding film 12 is adjusted so that the optical density at the exposure wavelength is 2.0 or more, preferably 2.8 or more. The thickness of the light-shielding film 12 is preferably within a range of, for example, 35 nm to 80 nm, particularly 40 nm to 75 nm. If the thickness of the light-shielding film 12 is within the above numerical range, the optical density at the exposure wavelength becomes sufficiently high, and high transfer performance can be imparted to the transmission mask 100 including the light-shielding film 12.

[0037] The thickness of the light-shielding films 22, 32 varies depending on the transmittance of the semi-transparent films 24, 34, but is adjusted so that the optical density of the light-shielding films 22, 32 at the exposure wavelength is 1.0 or more, or the optical density of the laminate of the light-shielding films 22, 32 and the semi-transparent films 24, 34 at the exposure wavelength is 2.0 or more, preferably 2.8 or more. For example, when the transmittance of the semi-transparent films 24, 34 is 6%, the thickness of the light-shielding films 22, 32 is preferably in the range of 25 nm to 75 nm, particularly 30 nm to 70 nm. If the thickness of the light-shielding films 22, 32 is within the above numerical range, the optical density at the exposure wavelength becomes sufficiently high, and high transfer performance can be imparted to the transmission masks 200, 300 equipped with the light-shielding films 22, 32. The light-shielding films 12, 22, and 32 are light-shielding films that have resistance to etching with an oxygen-containing chlorine-based gas, and can be etched with a fluorine-based gas or an oxygen-free chlorine-based gas.

[0038] (Absorption membrane) The absorbing film 42 is a thin film having a lower reflectance for light with a wavelength of 13.5 nm than the multilayer reflective film 44. The absorbing film 42 has a reflectance for light with a wavelength of 13.5 nm, for example, in the range of 0% or more and less than 6.5%, and preferably 0% or more and less than 2%. If the thickness of the absorbing film 42 is within the above numerical range, the reflectance of the multilayer reflective film 44 for EUV light becomes sufficiently low, and high transfer performance can be imparted to the reflective mask 400 including the absorbing film 42.

[0039] The absorbing film 42 is, for example, a single layer film made of one or more compounds selected from a tantalum compound, an indium compound, and a tin compound, or a mixed film or a multi-layer film of these compounds. Specifically, the absorbing film 42 made of a tantalum compound is a single layer film containing tantalum and one or more elements selected from silicon, nitrogen, boron, oxygen, carbon, and molybdenum, or a multi-layer film or a gradient film thereof. The absorbing film 42 made of an indium compound is a single layer film containing indium and one or more elements selected from nitrogen, boron, oxygen, and carbon, or a multi-layer film or a gradient film thereof. The absorbing film 42 made of a tin compound is a single layer film containing tin and one or more elements selected from nitrogen, boron, oxygen, and carbon, or a multi-layer film or a gradient film thereof. In particular, since indium compounds and tin compounds have low reflectance to EUV light and allow the absorbing film 42 to be thin, it is desirable for the absorbing film 42 to contain at least one of an indium compound and a tin compound.

[0040] The tantalum compound may contain tantalum in an element ratio of 10 atomic % to 95 atomic % in the entire tantalum compound, more preferably in the range of 17 atomic % to 75 atomic % in the entire tantalum compound, and even more preferably in the range of 25 atomic % to 55 atomic % in the entire tantalum compound. If the tantalum content is within the above numerical range, the light absorption property is further improved. The indium compound may contain indium in an element ratio of 10 atomic % to 95 atomic % in the entire indium compound, more preferably in an amount of 22 atomic % to 75 atomic % in the entire indium compound, and even more preferably in an amount of 35 atomic % to 55 atomic % in the entire indium compound. If the indium content is within the above numerical range, the light absorption property is further improved. The tin compound may contain tin in an element ratio of 5 atomic % to 95 atomic % in the entire tin compound, more preferably in the range of 15 atomic % to 75 atomic % in the entire tin compound, and even more preferably in the range of 25 atomic % to 55 atomic % in the entire tin compound. If the tin content is within the above numerical range, the light absorption is further improved.

[0041] The thickness of the absorbing film 42 is adjusted so that the reflectance to EUV light is less than 6%. The thickness of the absorbing film 42 is preferably, for example, in the range of 17 nm to 90 nm, particularly in the range of 25 nm to 75 nm. If the thickness of the absorbing film 42 is within the above numerical range, the reflectance to EUV light is sufficiently low, and high transfer performance can be imparted to the reflective mask 400 including the absorbing film 42. The absorbing film 42 is an absorbing film that has resistance to etching with an oxygen-containing chlorine-based gas, and can be etched with a fluorine-based gas or an oxygen-free chlorine-based gas.

[0042] (Hard Mask) The hard masks 13, 23, 33, and 43 are, for example, a single layer film containing at least one metal element selected from titanium, zirconium, niobium, hafnium, beryllium, aluminum, indium, and tin, or a multilayer film or gradient film thereof. The above-mentioned metal elements have lower surface free energy than chromium, so that the hard masks containing these metal elements have higher adhesion to the resist pattern than the hard masks that do not contain the above-mentioned metal elements and are mainly composed of chromium, and are located on the outermost surface far from the substrates 11, 21, 31, and 41.

[0043] The film thickness of the hard masks 13, 23, 33, and 43 is preferably in the range of 2 nm to 20 nm, particularly in the range of 4 nm to 15 nm, in order to suppress damage to the resist pattern during hard mask etching and to provide (ensure) etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching. In this manner, the hard masks 13, 23, 33, and 43 according to this embodiment are resistant to etching with a fluorine-based gas or an oxygen-free chlorine-based gas, and can be etched with an oxygen-containing chlorine-based gas.

[0044] The hard masks 13, 23, 33, and 43 may contain at least one metal element selected from titanium, zirconium, niobium, hafnium, beryllium, aluminum, indium, and tin in an element ratio of the entire hard mask in a range of 10 atomic % to 95 atomic % or less, more preferably in a range of 20 atomic % to 70 atomic % or less, and even more preferably in a range of 30 atomic % to 60 atomic % or less. If the content of the above-mentioned metal element is within the above numerical range, the adhesion to the resist pattern is further improved. In particular, among the above-mentioned metal elements, hafnium and tin are preferable as metal elements to be added to the hard masks 13, 23, 33, and 43 because they have particularly low surface free energy compared to other elements.

[0045] In addition, when using the above metal elements that are not highly resistant to etching with fluorine-based gas or oxygen-free chlorine-based gas, it is preferable to make the hard mask a multi-layer film. For example, the hard mask 33, 43 is preferably composed of at least an adhesive layer 33b, 43b that is located farther from the substrate 31, 41 and contains the above metal element, and a lower layer 33a, 43a that is located closer to the substrate 31, 41 than the adhesive layer 33b, 43b and is made of a material that has high etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching, and it is particularly preferable that the lower layer 33a, 43a contains a chromium compound that has excellent etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching. The lower layer 33a, 43a containing a chromium compound is a single layer film containing chromium and one or more elements selected from nitrogen, oxygen, and carbon, or a multi-layer film or a gradient film thereof. Here, the above-mentioned "material having high etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching" means that the ratio of the etching rate of the above-mentioned metal element during fluorine-based gas or oxygen-free chlorine-based gas etching to the etching rate of the material having high etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching during fluorine-based gas or oxygen-free chlorine-based gas etching (etching rate of the material having high etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching during fluorine-based gas or oxygen-free chlorine-based gas etching / etching rate of the above-mentioned metal element during fluorine-based gas or oxygen-free chlorine-based gas etching) is less than 1.

[0046] The lower layers 33a, 43a may contain chromium in an elemental ratio of 10 atomic % to 95 atomic % inclusive, more preferably 40 atomic % to 95 atomic % inclusive, and even more preferably 50 atomic % to 95 atomic % inclusive, in the entire lower layers 33a, 43a. If the chromium content falls within the above numerical range, the etching resistance to fluorine-based gas or oxygen-free chlorine-based gas etching is further improved.

[0047] Thus, the hard mask 33, 43 may be composed of a plurality of layers, and may have an adhesive layer 33b, 43b containing the above-mentioned metal element at least on the outermost surface, and a lower layer 33a, 43a having higher resistance to fluorine-based gas or oxygen-free chlorine-based gas etching than the adhesive layer 33b, 43b on the substrate 31, 41 side than the adhesive layer 33b, 43b. Here, the adhesive layer 33b, 43b of the hard mask 33, 43 may contain one or more metal elements selected from titanium, zirconium, niobium, hafnium, beryllium, aluminum, indium, and tin in an element ratio of the entire adhesive layer 33b, 43b in a range of 10 atomic % to 95 atomic %, more preferably in a range of 20 atomic % to 70 atomic %, and even more preferably in a range of 30 atomic % to 60 atomic %. If the content of the above-mentioned metal element is within the above numerical range, the adhesion to the resist pattern is further improved. In particular, among the above-mentioned metal elements, hafnium and tin have particularly low surface free energy compared to other elements, and are therefore preferable as metal elements to be added to the adhesion layers 33b and 43b.

[0048] In addition, the above-mentioned "lower layer 33a, 43a having higher resistance to fluorine-based gas or oxygen-free chlorine-based gas etching than the adhesion layer 33b, 43b" means that the ratio of the etching rate of the adhesion layer 33b, 43b when etched with fluorine-based gas or oxygen-free chlorine-based gas to the etching rate of the lower layer 33a, 43a when etched with fluorine-based gas or oxygen-free chlorine-based gas (etching rate of the lower layer 33a, 43a when etched with fluorine-based gas or oxygen-free chlorine-based gas / etching rate of the adhesion layer 33b, 43b when etched with fluorine-based gas or oxygen-free chlorine-based gas) is less than 1.

[0049] The thickness of the adhesion layers 33b and 43b is preferably in the range of 1 nm to 10 nm, particularly in the range of 2 nm to 5 nm. If the thickness of the adhesion layers 33b and 43b is within the above numerical range, the adhesion to the resist pattern can be sufficiently improved. The thickness of the lower layers 33a, 43a is preferably in the range of 1 nm to 19 nm, particularly in the range of 2 nm to 10 nm. If the thickness of the lower layers 33a, 43a is within the above range, the etching resistance against etching with a fluorine-based gas or an oxygen-free chlorine-based gas can be sufficiently improved.

[0050] (semi-transparent film) The semi-transparent films 24, 34 are located between the substrates 21, 31 and the light-shielding films 22, 32, are resistant to oxygen-containing chlorine-based gas etching, can be etched with a fluorine-based gas or an oxygen-free chlorine-based gas, and can invert the phase difference of light with a wavelength of 193 nm by a desired amount. "Able to invert the phase difference of light with a wavelength of 193 nm by a desired amount" means that the phase difference of light with a wavelength of 193 nm can be inverted within a range of 160 degrees or more and 220 degrees or less, as described below.

[0051] The semitransparent films 24, 34 are single-layer films made of one or more compounds selected from silicon compounds and tantalum compounds, or mixed films or multi-layer films of these compounds. The semitransparent films 24, 34 containing a silicon compound are single-layer films containing silicon and one or more elements selected from nitrogen, boron, oxygen, carbon, and molybdenum, or multi-layer films or gradient films thereof, and the transmittance and phase difference for the exposure wavelength are adjusted by appropriately selecting the composition and film thickness. The semitransparent films 24, 34 containing a tantalum compound are single-layer films containing tantalum and one or more elements selected from silicon, nitrogen, boron, oxygen, carbon, and molybdenum, or multi-layer films or gradient films thereof, and the transmittance and phase difference for the exposure wavelength are adjusted by appropriately selecting the composition and film thickness.

[0052] The transmittance value of the semi-transparent films 24, 34 is within the range of 3% to 80%, and the optimum transmittance can be appropriately selected according to the desired LSI circuit pattern. The value of the phase difference in the semitransparent films 24, 34 is preferably in the range of 160 degrees or more and 220 degrees or less, particularly in the range of 175 degrees or more and 190 degrees or less. When etching the semitransparent film 24, it is common to simultaneously dig the substrate 21 by about 1 nm to 3 nm to prevent the semitransparent film 24 from being removed and to fine-tune the phase difference. Therefore, it is necessary to form the semitransparent film 24 with a phase difference smaller than the value desired when the mask is completed, taking into account the amount of digging in the substrate 21. On the other hand, since the etching of the semitransparent film 34 stops at the protective film 35, there is no process of intentionally digging in the substrate 31. Therefore, it is not necessary to form the semitransparent film 34 with a phase difference smaller than the value desired when the mask is completed.

[0053] (Multilayer reflective film) The multilayer reflective film 44 is a film having a multilayer structure located between the substrate 41 and the absorbing film 42, and is a film that reflects light with a wavelength of 13.5 nm. The multilayer reflective film 44 reflects EUV light such as light with a wavelength of 13.5 nm, and is made of a combination of materials with significantly different refractive indices for EUV light. For example, it can be formed by repeatedly stacking layers of combinations of molybdenum and silicon, or molybdenum and beryllium, for example, about 40 times. The multilayer reflective film 44 is, for example, a thin film capable of reflecting 50% or more of light with a wavelength of 13.5 nm, and preferably a thin film capable of reflecting 60% or more of the light.

[0054] (protective film) The protective films 25, 35, 45 are located between the substrates 21, 31, 41 and the thin light-shielding films 22, 32 or the absorbing film 42, and are layers that are resistant to etching with fluorine-based gas or non-oxygen-containing chlorine-based gas and can be etched with oxygen-containing chlorine-based gas or oxygen-based gas. The protective films 25, 35, 45 are single-layer films containing one or more elements selected from chromium, ruthenium, niobium, and aluminum, or multi-layer films or gradient films thereof. The protective films 25, 35, 45 may also be single-layer films containing one or more elements selected from chromium, ruthenium, niobium, and aluminum and one or more elements selected from oxygen, nitrogen, and fluorine, or multi-layer films or gradient films thereof. The thickness of the protective films 25, 35, 45 is preferably within a range of 3 nm to 20 nm, particularly 5 nm to 15 nm, in order to ensure etching resistance against fluorine-based gases.

[0055] The above-mentioned light-shielding film, absorbing film, hard mask, adhesive layer, underlayer, semi-transparent film, multilayer reflective film, and protective film can be formed by a known method. The most preferable method for obtaining a film with excellent uniformity is a sputtering film formation method, but the present embodiment does not need to be limited to the sputtering film formation method.

[0056] The target and the sputtering gas are selected according to the film composition. For example, a method for forming a film containing silicon can be mentioned in which a silicon-containing target is used and reactive sputtering is performed in a gas consisting of only an inert gas such as argon gas, in a gas consisting of only a reactive gas such as oxygen, or in a mixed gas of an inert gas and a reactive gas. The flow rate of the sputtering gas can be adjusted according to the film characteristics, and may be constant during film formation, or may be changed according to the desired composition when the amount of oxygen or the amount of nitrogen is to be changed in the thickness direction of the film. When the amount of oxygen or the amount of nitrogen is to be changed in the thickness direction of the film, the power applied to the target, the distance between the target and the substrate, or the pressure in the film formation chamber may be adjusted. In addition, for example, in the formation of a film containing silicon and a metal, a target with an adjusted content ratio of silicon and metal may be used alone as the target, or a plurality of targets may be appropriately selected from a silicon target, a metal target, and a target consisting of silicon and a metal. The transmission type and reflection type masks can be obtained by patterning or removing the films of the transmission type and reflection type mask blanks of the present embodiment described above into desired patterns.

[0057] (Mask blank and mask manufacturing method) Preferred embodiments of the transmission type and reflection type mask blanks and the method of manufacturing the transmission type and reflection type masks of this embodiment will be described below. FIG. 5 is a schematic cross-sectional view showing the steps of manufacturing a transmission mask 100 using the transmission mask blank 10 shown in FIG. 1. FIG. 5(a) shows a process of applying a resist film onto a hard mask 13 constituting the transmission mask blank 10, drawing the resist film, and then performing a development process to form a resist pattern 16. FIG. 5(b) shows a process of patterning the hard mask 13 by oxygen-containing chlorine-based gas etching along the resist pattern 16. FIG. 5(c) shows a process of peeling and removing the remaining resist pattern 16, followed by cleaning. FIG. 5(d) shows a process of patterning the light-shielding film 12 by fluorine-based gas etching along the pattern of the hard mask 13. FIG. 5(e) shows a process of removing the hard mask 13 by oxygen-containing chlorine-based gas etching, followed by cleaning. In this way, the transmission mask 100 according to the first embodiment is manufactured.

[0058] FIG. 6 is a schematic cross-sectional view showing the steps of manufacturing a transmission mask 200 using the transmission mask blank 20 shown in FIG. 2. FIG. 6(a) shows a process of applying a resist film onto a hard mask 23 constituting the transmission mask blank 20, drawing the resist film, and then performing a development process to form a resist pattern (first resist pattern) 26. FIG. 6(b) shows a process of patterning the hard mask 23 by oxygen-containing chlorine-based gas etching along the resist pattern 26. FIG. 6(c) shows a process of peeling off and removing the remaining resist pattern 26, followed by cleaning. FIG. 6(d) shows a process of patterning the light-shielding film 22 by fluorine-based gas etching along the pattern of the hard mask 23. FIG. 6(e) shows a process of patterning the protective film 25 by oxygen-based gas etching along the patterns of the hard mask 23 and the light-shielding film 22. FIG. 6(f) shows a process of patterning the semi-transparent film 24 by fluorine-based gas etching along the patterns of the hard mask 23, the light-shielding film 22, and the protective film 25. FIG. 6(g) shows a process of removing the hard mask 23 by oxygen-containing chlorine-based gas etching and then cleaning. FIG. 6(h) shows a process of newly forming a second resist pattern 27. FIG. 6(i) shows a process of removing the light-shielding film 22 in the area not covered by the second resist pattern 27 by fluorine-based gas etching. FIG. 6(j) shows a process of removing the protective film 25 in the area not covered by the second resist pattern 27 by oxygen-based gas etching. FIG. 6(k) shows a process of peeling off and removing the remaining second resist pattern 27 and then cleaning. In this manner, the transmission mask 200 according to the second embodiment is manufactured.

[0059] FIG. 7 is a schematic cross-sectional view showing the steps of manufacturing a transmission mask 300 using the transmission mask blank 30 shown in FIG. 3. FIG. 7(a) shows a process of applying a resist film onto the adhesive layer 33b of the hard mask 33 constituting the transmission mask blank 30, drawing, and then performing a development process to form a resist pattern (first resist pattern) 36. FIG. 7(b) shows a process of continuously patterning the hard mask 33 consisting of the adhesive layer 33b and the lower layer 33a by oxygen-containing chlorine-based gas etching along the resist pattern 36. FIG. 7(c) shows a process of peeling off and removing the remaining resist pattern 36, followed by cleaning. FIG. 7(d) shows a process of patterning the light-shielding film 32 by oxygen-free chlorine-based gas etching along the pattern of the hard mask 33 consisting of the adhesive layer 33b and the lower layer 33a, and at the same time peeling off the adhesive layer 33b of the hard mask 33. FIG. 7(e) shows a process of patterning the semi-transparent film 34 by fluorine-based gas etching along the pattern of the lower layer 33a of the hard mask 33 and the light-shielding film 32. FIG. 7(f) shows a process of patterning the protective film 35 by oxygen-based gas etching along the pattern of the lower layer 33a of the hard mask 33, the light-shielding film 32, and the semi-transparent film 34. FIG. 7(g) shows a process of removing the lower layer 33a of the hard mask by oxygen-containing chlorine-based gas etching and then cleaning. FIG. 7(h) shows a process of newly forming a second resist pattern 37. FIG. 7(i) shows a process of removing the light-shielding film 32 in the region not covered by the second resist pattern 37 by oxygen-free chlorine-based gas etching. FIG. 7(j) shows a process of peeling off and removing the remaining second resist pattern 37 and then cleaning. In this way, the transmission mask 300 according to the third embodiment is manufactured.

[0060] FIG. 8 is a schematic cross-sectional view showing the steps of manufacturing a reflective mask 400 using the reflective mask blank 40 shown in FIG. 4. FIG. 8(a) shows a process of applying a resist film onto the adhesive layer 43b of the hard mask 43 constituting the reflective mask blank 40, drawing, and then performing a development process to form a resist pattern (first resist pattern) 46. FIG. 8(b) shows a process of continuously patterning the hard mask 43 consisting of the adhesive layer 43b and the lower layer 43a by oxygen-containing chlorine-based gas etching along the resist pattern 46. FIG. 8(c) shows a process of peeling and removing the remaining resist pattern 46, and then cleaning. FIG. 8(d) shows a process of patterning the absorbing film 42 by oxygen-free chlorine-based gas etching along the pattern of the hard mask 43 consisting of the adhesive layer 43b and the lower layer 43a, and then peeling off the adhesive layer 43b of the hard mask 43, and then cleaning. In this way, the reflective mask 400 according to the fourth embodiment is manufactured.

[0061] As described above, the manufacturing method of the transmissive mask 100, 200, 300 or the reflective mask 400 using the transmissive mask blank 10, 20, 30 or the reflective mask blank 40 according to this embodiment includes the steps of forming resist patterns 16, 26, 36, 46 on the hard masks 13, 23, 33, 43 of the mask blanks 10, 20, 30, 40, etching the hard masks 13, 23, 33, 43 with an oxygen-containing chlorine-based gas using the resist patterns 16, 26, 36, 46 as a mask to form a hard mask pattern, and etching the thin light-shielding films 12, 22, 32 or the absorbing film 42 with a fluorine-based gas or an oxygen-free chlorine-based gas using the hard mask pattern as a mask to form a thin film pattern.

[0062] In each process of FIG. 5(a), FIG. 6(a), FIG. 7(a), and FIG. 8(a), either a positive resist or a negative resist can be used as the material of the resist film, but it is preferable to use a chemically amplified resist for electron beam writing that enables the formation of a high-precision pattern. The thickness of the resist film is, for example, in the range of 50 nm to 200 nm. In particular, when producing a transmission type or a reflection type mask that requires the formation of a fine pattern, in order to prevent the pattern from collapsing, it is necessary to make the resist film thin so that the aspect ratio of the resist patterns 16, 26, 36, and 46 does not become large, and a thickness of 150 nm or less is preferable. On the other hand, the lower limit of the thickness of the resist film is determined by comprehensively considering conditions such as the etching resistance of the resist material used, and is preferably 60 nm or more. When a chemically amplified resist for electron beam writing is used as the resist film, the energy density of the electron beam during writing is 10 μC / cm 2 More than 200μC / cm 2 After this drawing, a heat treatment and a development treatment are carried out to obtain resist patterns 16, 26, 36, and 46.

[0063] In addition, in each process of Fig. 5(b), Fig. 6(b), Fig. 7(b), and Fig. 8(b), the conditions of the oxygen-containing chlorine-based gas etching for patterning the hard masks 13 and 23, and the conditions of the oxygen-containing chlorine-based gas etching for subsequently patterning the hard masks 33 and 43 composed of the adhesion layers 33b and 43b and the lower layers 33a and 43a, may be the same as the known conditions that have been used conventionally to remove chromium compound films, and may be, for example, a gas containing chlorine gas and oxygen gas, or may be a mixture of chlorine gas, oxygen gas, and inert gas such as nitrogen gas or helium gas as necessary. The light-shielding films 12, 22, and 32 and the absorbing film 42 have resistance to the oxygen-containing chlorine-based gas etching, and therefore remain without being removed or patterned in this process.

[0064] In addition, in each of the steps of Figures 5(c), 6(c), 7(c), and 8(c), the resist patterns 16, 26, 36, and 46 can be removed by etching, but are generally removed by wet stripping using a stripping liquid. 5(d) and 6(d), the conditions of the fluorine-based gas etching for patterning the light-shielding films 12 and 22 may be the same as those known in the art that have been used for etching silicon compounds, and the fluorine-based gas is generally CF4, C2F6, or SF6, and may be a mixture of an inert gas such as nitrogen gas or helium gas as necessary. The hard masks 13 and 23 and the protective film 25 are resistant to the fluorine-based gas etching, and therefore remain without being removed or patterned in this process.

[0065] In addition, in each step of FIG. 7(d) and FIG. 8(d), the conditions of the oxygen-free chlorine-based gas etching for patterning the light-shielding film 32 or the absorbing film 42 may be the same as the known conditions that have been used in the past when etching tantalum compounds, for example, chlorine gas may be used, or in addition to chlorine gas, an inert gas such as nitrogen gas or helium gas may be mixed as necessary. The adhesion layers 33b and 43b of the hard masks 33 and 43 are removed in this step because they have a relatively low resistance to the oxygen-free chlorine-based gas etching. The lower layers 33a and 43a of the hard masks 33 and 43, the semi-transparent film 34, and the protective film 45 are resistant to the oxygen-free chlorine-based gas etching, so they are not removed or patterned in this step and remain.

[0066] 6(e) and 7(f), the conditions for the oxygen-based gas etching for patterning the protective films 25 and 35 may be, for example, oxygen gas, or may be a mixture of oxygen gas and an inert gas such as nitrogen gas or helium gas as necessary. The hard mask 23, the lower layer 33a of the hard mask 33, and the semi-transparent film 24 are resistant to oxygen-based gas etching, and therefore remain without being removed or patterned in this process.

[0067] In addition, in each process of FIG. 6(f) and FIG. 7(e), the conditions of the fluorine-based gas etching for patterning the semi-transparent films 24 and 34 may be the same as those known in the art that have been used for etching silicon compound films. The fluorine-based gas is generally CF4, C2F6, or SF6, and may be mixed with an inert gas such as nitrogen gas or helium gas as necessary. The hard mask 23, the lower layer 33a of the hard mask, and the protective film 35 are resistant to fluorine-based gas etching, and therefore remain without being removed or patterned in this process. In FIG. 6(f), the substrate 21 is generally recessed by about 1 nm to 3 nm at the same time as patterning the semi-transparent film 24, to prevent the semi-transparent film 24 from being removed, and to fine-tune the phase difference. On the other hand, in FIG. 7(e), the protective film 35 is resistant to fluorine-based gas etching, so that the substrate 31 is not recessed when the semi-transparent film 34 is patterned. Therefore, no phase difference error occurs due to the pattern dependency of the substrate engraving amount or the mask position dependency, and a more uniform phase difference can be realized for all patterns and all positions on the mask.

[0068] 5(e), 6(g), and 7(g), the conditions of the oxygen-containing chlorine-based gas etching for removing the hard masks 13, 23, and the lower layer 33a of the hard mask 33 may be the same as those known in the art that have been used for removing chromium compound films, and may be, for example, a gas containing chlorine gas and oxygen gas, or a mixture of chlorine gas, oxygen gas, and an inert gas such as nitrogen gas or helium gas as necessary. Since the light-shielding films 12, 22, and 32 are all resistant to the oxygen-containing chlorine-based gas etching, they are left without being removed or patterned in this process.

[0069] In addition, in each step of Figure 6(h) and Figure 7(h), the drawing method may be laser drawing, which is less accurate than electron beam drawing, and the second resist patterns 27, 37 may be obtained by applying a resist film, performing electron beam drawing or laser drawing, and then performing a development process. 6(i), the conditions for fluorine-based gas etching to remove the light-shielding film 22 may be the same as those known in the art that have been used to etch silicon compounds, and the fluorine-based gas is generally CF4, C2F6, or SF6, and may be mixed with an inert gas such as nitrogen gas or helium gas as necessary. The protective film 25 is resistant to fluorine-based gas etching, and is therefore left without being removed or patterned in this process.

[0070] 7(i), the conditions for the oxygen-free chlorine-based gas etching for removing the light-shielding film 32 may be the same as those known in the art that have been used for etching tantalum compounds, and may be, for example, chlorine gas, or a mixture of chlorine gas and an inert gas such as nitrogen gas or helium gas as necessary. The semi-transparent film 34 is resistant to the oxygen-free chlorine-based gas etching, and is therefore left without being removed or patterned in this process.

[0071] 6(j), the conditions for the oxygen-based gas etching for removing the protective film 25 may be, for example, oxygen gas, or may be a mixture of oxygen gas and an inert gas such as nitrogen gas or helium gas as necessary. The semi-transparent film 24 is resistant to oxygen-based gas etching, and therefore remains without being removed or patterned in this process. In the steps of FIG. 6(k) and FIG. 7(j), the second resist patterns 27 and 37 can be removed by etching, but are generally removed by wet stripping using a stripping solution.

[0072] [Example] The embodiments of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0073] (Example 1 and Comparative Example 1) A light-shielding film consisting of silicon, molybdenum, oxygen, and nitrogen was deposited to a thickness of 58 nm on a substrate transparent to the exposure wavelength using a DC sputtering device with two targets. The targets used were molybdenum and silicon, and the sputtering gases used were argon, oxygen, and nitrogen. The composition of this light-shielding film was analyzed by ESCA, and found to be Si:Mo:O:N = 45:15:5:35 (atomic percentage ratio). In addition, the optical density of this light-shielding film at the exposure wavelength of ArF light (193 nm) was measured using a spectrophotometer, and found to be 3.0. Next, a hard mask made of hafnium nitride was deposited on the light-shielding film to a thickness of 5 nm using an RF sputtering device. The target was hafnium nitride, and the sputtering gas was argon. The composition of this hard mask was analyzed by ESCA and found to be Hf:N=50:50 (atomic ratio).

[0074] In this way, a transmission type mask blank of Example 1 was obtained, in which a light-shielding film made of silicon, molybdenum, oxygen, and nitrogen, and a hard mask made of hafnium and nitrogen were laminated in this order on a substrate transparent to the exposure wavelength. The light-shielding film thus formed was a thin film that had resistance to oxygen-containing chlorine-based gas etching and could be etched with a fluorine-based gas or an oxygen-free chlorine-based gas. The hard mask thus formed was also a mask that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched with an oxygen-containing chlorine-based gas.

[0075] Next, a negative chemically amplified electron beam resist was spin-coated on this hard mask to a thickness of 100 nm, and the pattern was printed with a dose of 35 μC / cm 2The resist was irradiated with an electron beam at 4000 K, heat-treated at 110° C. for 10 minutes, and developed by paddle development for 90 seconds to form a resist line pattern. Furthermore, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM (Scanning Electron Microscope). The height of the resist line pattern in the film thickness direction was 95 nm, the dimensions of the minimum resolution pattern were 40 nm, and the aspect ratio of the minimum resolution pattern was 2.4.

[0076] Next, as Comparative Example 1, a resist line pattern was formed on a mask blank in which a light-shielding film mainly made of silicon and a hard mask mainly made of chromium were laminated in this order on a substrate transparent to ArF light (wavelength 193 nm) that has been conventionally used, in the same manner as in Example 1. Next, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 95 nm, the dimensions of the minimum resolution pattern were 52 nm, and the aspect ratio of the minimum resolution pattern was 1.8. Therefore, it was confirmed that the resist line pattern of Example 1 was capable of forming a resist pattern having a smaller minimum resolution pattern dimension and a larger aspect ratio than Comparative Example 1.

[0077] Next, a hard mask was patterned on the transmission mask blank of Example 1 using an etching device to obtain a hard mask pattern. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, there was no damage to the light-shielding film. Next, the resist pattern was stripped and cleaned by washing with sulfuric acid and hydrogen peroxide. Next, the light-shielding film was patterned using an etching device to obtain a light-shielding film pattern. CF4 and oxygen were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, the amount of damage to the hard mask pattern was 1 nm, and there was no occurrence of micro defects or disappearance of the hard mask pattern.

[0078] Next, the hard mask pattern was removed using an etching device. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 10 mTorr, the ICP power to 500 W, and the bias power to 10 W. Overetching was performed by 200%. During this process, there was no damage to the light-shielding film pattern. In this way, a transmission mask of Example 1 was obtained, which was composed of a transparent region made of a substrate transparent to the exposure wavelength, and a light-shielding region formed by laminating a substrate transparent to the exposure wavelength and a light-shielding film pattern.

[0079] (Example 2 and Comparative Example 2) A semi-transparent film consisting of silicon, oxygen, and nitrogen was deposited to a thickness of 83 nm on a substrate transparent to the exposure wavelength using a DC sputtering device. Silicon was used as the target, and argon, oxygen, and nitrogen were used as the sputtering gas. The composition of this semi-transparent film was analyzed by ESCA and found to be Si:O:N=40:30:30 (atomic percentage). Next, a protective film consisting of ruthenium and niobium was deposited on the semi-transparent film with a thickness of 7 nm using an ion sputtering device. A ruthenium-niobium alloy was used as the target, and xenon was used as the sputtering gas. The composition of this protective film was analyzed by ESCA and found to be Ru:Nb=85:15 (atomic percentage).

[0080] Next, a light-shielding film made of silicon, molybdenum, oxygen, and nitrogen was formed on this protective film to a thickness of 48 nm using a DC sputtering device with two targets. The targets used were molybdenum and silicon, and the sputtering gases used were argon, oxygen, and nitrogen. The composition of this light-shielding film was analyzed by ESCA and found to be Si:Mo:O:N=45:15:5:35 (atomic % ratio). In addition, the optical density of the laminate consisting of this semi-transparent film, protective film, and light-shielding film was measured with a spectrophotometer at the exposure wavelength of ArF light (193 nm), and found to be 3.0. Next, a hard mask made of hafnium nitride was deposited on the light-shielding film to a thickness of 5 nm using an RF sputtering device. The target was hafnium nitride, and the sputtering gas was argon. The composition of this hard mask was analyzed by ESCA and found to be Hf:N=50:50 (atomic ratio).

[0081] In this way, a translucent film made of silicon, oxygen, and nitrogen, a protective film made of ruthenium and niobium, a light-shielding film made of silicon, molybdenum, oxygen, and nitrogen, and a hard mask made of hafnium and nitrogen were laminated in this order on a substrate transparent to the exposure wavelength, to obtain a transmission type mask blank of Example 2. The semitransparent film thus formed was a film that had resistance to oxygen-containing chlorine-based gas etching and could be etched by fluorine-based gas or oxygen-free chlorine-based gas. The protective film thus formed was a film that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched by oxygen-containing chlorine-based gas or oxygen-free gas. The light-shielding film thus formed was a thin film that had resistance to oxygen-containing chlorine-based gas etching and could be etched by fluorine-based gas or oxygen-free chlorine-based gas. The hard mask thus formed was a mask that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched by oxygen-containing chlorine-based gas.

[0082] Next, a negative chemically amplified electron beam resist was spin-coated on this hard mask to a thickness of 100 nm, and the pattern was printed with a dose of 35 μC / cm 2 The resist was then subjected to electron beam lithography at 100°C for 10 minutes, heat-treated at 110°C for 10 minutes, and developed by paddle development for 90 seconds to form a resist line pattern. The height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 95 nm, the dimensions of the minimum resolution pattern were 40 nm, and the aspect ratio of the minimum resolution pattern was 2.4.

[0083] Next, as Comparative Example 2, a resist line pattern was formed on a mask blank in which a light-shielding film mainly made of silicon and a hard mask mainly made of chromium were laminated in this order on a substrate transparent to ArF light (wavelength 193 nm) that has been conventionally used, in the same manner as in Example 2. Next, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 95 nm, the dimensions of the minimum resolution pattern were 52 nm, and the aspect ratio of the minimum resolution pattern was 1.8. Therefore, it was confirmed that the resist line pattern of Example 2 was capable of forming a resist pattern having a smaller minimum resolution pattern dimension and a larger aspect ratio than Comparative Example 2.

[0084] Next, a hard mask was patterned on the transmission mask blank of Example 2 using an etching device to obtain a hard mask pattern. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, there was no damage to the light-shielding film. Next, the resist pattern was stripped and cleaned by washing with sulfuric acid and hydrogen peroxide. Next, the light-shielding film was patterned using an etching device to obtain a light-shielding film pattern. CF4 and oxygen were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, the damage to the hard mask pattern was 1 nm, there was no damage to the protective film, and there was no occurrence of micro-defects or disappearance of the hard mask pattern.

[0085] Next, the protective film was patterned using an etching device to obtain a protective film pattern. Oxygen and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. During this process, there was no damage to the hard mask pattern or the semi-transparent film. Next, the semi-transparent film was patterned using an etching device to obtain a semi-transparent film pattern. CF4 and oxygen were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Etching was stopped when the substrate transparent to the exposure wavelength was dug an average of 3 nm. At this time, the damage amount of the hard mask pattern was 1 nm, and no micro defects were generated or the hard mask pattern was lost.

[0086] Next, the hard mask pattern was removed using an etching device. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 10 mTorr, the ICP power to 500 W, and the bias power to 10 W. Overetching was performed by 200%. During this process, there was no damage to the light-shielding film pattern. Next, a positive resist film was spin-coated, and patterned using a laser patterning device, followed by development to form a second resist pattern. Next, the light-shielding film pattern was removed using an etching device. CF4 and oxygen were used as the etching gas, and the gas pressure was set to 10 mTorr, the ICP power to 500 W, and the bias power to 10 W. Overetching was performed by 200%. During this process, there was no damage to the protective film pattern.

[0087] Next, the protective film pattern was removed using an etching device. Oxygen and helium were used as the etching gas, and the gas pressure was set to 10 mTorr, the ICP power to 500 W, and the bias power to 10 W. Overetching was performed by 200%. During this process, there was no damage to the semi-transparent film pattern. Next, the second resist pattern was peeled off and washed by washing with sulfuric acid / hydrogen peroxide to obtain a transmission mask of Example 2, which is composed of a transparent region made of a substrate transparent to the exposure wavelength, a semi-transparent region made by laminating a substrate transparent to the exposure wavelength and a semi-transparent film pattern, and a light-shielding region made by laminating a substrate transparent to the exposure wavelength, a semi-transparent film pattern, a protective film pattern, and a light-shielding film pattern.

[0088] (Example 3 and Comparative Example 3) A protective film consisting of ruthenium and niobium was deposited to a thickness of 7 nm on a substrate transparent to the exposure wavelength using an ion sputtering device. A ruthenium-niobium alloy was used as the target, and xenon was used as the sputtering gas. The composition of this protective film was analyzed by ESCA and found to be Ru:Nb=85:15 (atomic percentage). Next, a semi-transparent film consisting of silicon, molybdenum, oxygen, and nitrogen was deposited on this protective film to a thickness of 59 nm using a DC sputtering device with two targets. The targets used were molybdenum and silicon, and the sputtering gases used were argon, oxygen, and nitrogen. The composition of this semi-transparent film was analyzed by ESCA and found to be Si:Mo:O:N = 42:7:5:46 (atomic percentage).

[0089] Next, a light-shielding film made of tantalum and nitrogen was formed on this semi-transparent film with a thickness of 30 nm using a DC sputtering device. The target used was tantalum, and the sputtering gases used were argon and nitrogen. The composition of this light-shielding film was analyzed by ESCA, and found to be Ta:N=70:30 (atomic %). In addition, the optical density of the laminate consisting of this protective film, semi-transparent film, and light-shielding film was measured with a spectrophotometer at the exposure wavelength of ArF light (193 nm), and found to be 3.0.

[0090] Next, a hard mask lower layer made of chromium and nitrogen was deposited on the light-shielding film to a thickness of 5 nm using a DC sputtering device. Chromium was used as the target, and argon and nitrogen were used as the sputtering gas. The composition of the hard mask lower layer was analyzed by ESCA and found to be Cr:N=90:10 (atomic percentage). Next, a 2 nm thick adhesion layer of tin and oxygen was formed on the lower layer of the hard mask using a DC sputtering device. Tin oxide was used as the target, and argon and oxygen were used as the sputtering gas. The composition of the adhesion layer of the hard mask was analyzed by ESCA and found to be Sn:O=38:62 (atomic % ratio).

[0091] In this way, a transmission type mask blank of Example 3 was obtained, in which a protective film made of ruthenium and niobium, a semitransparent film made of silicon, molybdenum, oxygen and nitrogen, a light-shielding film made of tantalum and nitrogen, a lower layer of a hard mask made of chromium and nitrogen, and an adhesive layer of a hard mask made of tin and oxygen were laminated in this order on a substrate transparent to the exposure wavelength. The protective film thus formed was a film that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched by oxygen-containing chlorine-based gas or oxygen-based gas. The semitransparent film thus formed was a film that had resistance to oxygen-containing chlorine-based gas etching and could be etched by fluorine-based gas or oxygen-free chlorine-based gas. The light-shielding film thus formed was a film that had resistance to oxygen-containing chlorine-based gas etching and could be etched by fluorine-based gas or oxygen-free chlorine-based gas. The lower layer of the hard mask and the adhesive layer of the hard mask thus formed were masks that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched by oxygen-containing chlorine-based gas. Furthermore, the lower layer of the hard mask thus formed was a layer having higher resistance to etching with a fluorine-based gas or an oxygen-free chlorine-based gas than the adhesion layer of the hard mask.

[0092] Next, a negative chemically amplified electron beam resist was spin-coated on the adhesion layer of this hard mask to a thickness of 100 nm, and the pattern was formed with a dose of 35 μC / cm 2 The resist was then subjected to electron beam writing at 100°C, heat treatment at 110°C for 10 minutes, and development by paddle development for 90 seconds to form a resist line pattern (first resist pattern). Furthermore, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 95 nm, the dimensions of the minimum resolution pattern were 38 nm, and the aspect ratio of the minimum resolution pattern was 2.5.

[0093] Next, as Comparative Example 3, a resist line pattern was formed on a mask blank in which a light-shielding film mainly made of silicon and a hard mask mainly made of chromium were laminated in this order on a substrate transparent to ArF light (wavelength 193 nm) that has been conventionally used, in the same manner as in Example 3. Next, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 95 nm, the dimensions of the minimum resolution pattern were 52 nm, and the aspect ratio of the minimum resolution pattern was 1.8. Therefore, it was confirmed that the resist line pattern of Example 3 had a smaller minimum resolution pattern dimension and a larger aspect ratio than Comparative Example 3.

[0094] Next, the adhesive layer of the hard mask and the lower layer of the hard mask were patterned in succession using an etching device for the transmission mask blank of Example 3, to obtain a hard mask pattern consisting of an adhesive layer pattern and an underlayer pattern. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, there was no damage to the light-shielding film. Next, the resist pattern was stripped and cleaned by washing with sulfuric acid and hydrogen peroxide.

[0095] Next, the light-shielding film was patterned using an etching device to obtain a light-shielding film pattern. Chlorine and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, the damage amount of the adhesion layer pattern was 2 nm, and the adhesion layer pattern was lost, but the damage amount of the lower layer pattern was 1 nm, there was no damage to the semi-transparent film, and there was no occurrence of micro-defects or loss of the lower layer pattern.

[0096] Next, the semi-transparent film was patterned using an etching device to obtain a semi-transparent film pattern. CF4 and oxygen were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed by 10%. Due to the presence of a protective film, the etching was stopped without engraving the substrate, which is transparent to the exposure wavelength. At this time, the amount of damage to the lower layer pattern was 1 nm, there was no damage to the protective film, and no occurrence of micro-defects or disappearance of the lower layer pattern.

[0097] Next, the protective film was patterned using an etching device to obtain a protective film pattern. Oxygen and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed by 10%. During this process, there was no damage to the lower layer pattern. Next, the lower layer pattern was removed using an etching device. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 10 mTorr, the ICP power to 500 W, and the bias power to 10 W. Overetching was performed by 200%. During this process, there was no damage to the light-shielding film pattern.

[0098] Next, a positive resist film was spin-coated, and patterned using a laser patterning device, followed by development to form a second resist pattern. Next, the light-shielding film pattern was removed using an etching device. Chlorine and helium were used as the etching gas, and the gas pressure was set to 10 mTorr, the ICP power to 500 W, and the bias power to 10 W. Overetching was performed by 200%. During this process, there was no damage to the semi-transparent film pattern.

[0099] Next, the second resist pattern was peeled off and cleaned by washing with sulfuric acid / hydrogen peroxide to obtain a transmission mask of Example 3, which is composed of a transparent region made of a substrate transparent to the exposure wavelength, a semi-transparent region made of a substrate transparent to the exposure wavelength, a protective film pattern, and a semi-transparent film pattern laminated together, and a light-shielding region made of a substrate transparent to the exposure wavelength, a protective film pattern, a semi-transparent film pattern, and a light-shielding film pattern laminated together.

[0100] (Example 4 and Comparative Example 4) A multilayer reflective film was formed on a substrate with low thermal expansion due to exposure using a DC sputtering device, with 40 pairs of molybdenum and silicon layers stacked together to a thickness of 280 nm. The targets used were molybdenum for the molybdenum layers and silicon for the silicon layers, and argon was used as the sputtering gas. Analysis of the composition of this multilayer reflective film by ESCA revealed that the molybdenum layers had a Mo=100 (atomic %) ratio, and the silicon layers had a Si=100 (atomic %) ratio.

[0101] Next, a protective film made of ruthenium was deposited on the multilayer reflective film to a thickness of 3.5 nm using a DC sputtering device. The target was ruthenium, and the sputtering gas was argon. The composition of the protective film was analyzed by ESCA, and found to be Ru=100 (atomic %). Next, an absorber film made of tin and oxygen was formed on this protective film to a thickness of 30 nm using a DC sputtering device. The target was tin oxide, and the sputtering gas was argon and oxygen. The composition of this absorber film was analyzed by ESCA and found to be Sn:O=38:62 (atomic %).

[0102] Next, a hard mask lower layer consisting of chromium and nitrogen was deposited on the absorbing film to a thickness of 5 nm using a DC sputtering device. Chromium was used as the target, and argon and nitrogen were used as the sputtering gas. The composition of the hard mask lower layer was analyzed by ESCA and found to be Cr:N=90:10 (atomic % ratio). Next, a 2 nm thick adhesion layer of tin and oxygen was formed on the lower layer of the hard mask using a DC sputtering device. Tin oxide was used as the target, and argon and oxygen were used as the sputtering gas. The composition of the adhesion layer of the hard mask was analyzed by ESCA and found to be Sn:O=38:62 (atomic % ratio).

[0103] In this way, a reflective mask blank of Example 4 was obtained, in which a multilayer reflective film made of molybdenum and silicon, a protective film made of ruthenium, an absorbing film made of tin and oxygen, a lower layer of a hard mask made of chromium and nitrogen, and an adhesive layer of a hard mask made of tin and oxygen were laminated in this order on a substrate with small thermal expansion due to exposure. The multilayer reflective film thus formed was a film having a multilayer structure that reflects light with a wavelength of 13.5 nm. The protective film thus formed was a film that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched by oxygen-containing chlorine-based gas or oxygen-based gas. The absorbing film thus formed was a film that absorbs light with a wavelength of 13.5 nm, had resistance to oxygen-containing chlorine-based gas etching, and could be etched by fluorine-based gas or oxygen-free chlorine-based gas. The lower layer of the hard mask and the adhesive layer of the hard mask thus formed were masks that had resistance to fluorine-based gas or oxygen-free chlorine-based gas etching and could be etched by oxygen-containing chlorine-based gas. Furthermore, the lower layer of the hard mask thus formed was a layer having higher resistance to etching with a fluorine-based gas or an oxygen-free chlorine-based gas than the adhesion layer of the hard mask.

[0104] Next, a positive chemically amplified electron beam resist was spin-coated on the adhesion layer of this hard mask to a thickness of 100 nm, and the pattern was formed with a dose of 35 μC / cm 2 The resist was then subjected to electron beam writing at 100°C, heat treatment at 110°C for 10 minutes, and development by paddle development for 90 seconds to form a resist line pattern (first resist pattern). Furthermore, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 97 nm, the dimensions of the minimum resolution pattern were 43 nm, and the aspect ratio of the minimum resolution pattern was 2.3.

[0105] Next, as Comparative Example 4, a resist line pattern was formed on a mask blank in which a multilayer reflective film made of molybdenum and silicon, a protective film made of ruthenium, an absorbing film made of tantalum, and a hard mask made of chromium and nitrogen were laminated in this order on a substrate that has a small thermal expansion when irradiated with EUV light (wavelength 13.5 nm), which has been conventionally used. Next, the height of the resist line pattern in the film thickness direction was measured by AFM, and the dimensions of the minimum resolution pattern of the resist line pattern were measured by SEM. The height of the resist line pattern in the film thickness direction was 97 nm, the dimensions of the minimum resolution pattern were 57 nm, and the aspect ratio of the minimum resolution pattern was 1.7. Therefore, it was confirmed that the resist line pattern of Example 4 was capable of forming a resist pattern having a smaller minimum resolution pattern dimension and a larger aspect ratio than Comparative Example 4.

[0106] Next, the reflective mask blank of Example 4 was subjected to patterning of the adhesion layer of the hard mask and the lower layer of the hard mask in succession using an etching device, to obtain a hard mask pattern consisting of an adhesion layer pattern and an underlayer pattern. Chlorine, oxygen, and helium were used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed at 100%. At this time, there was no damage to the absorbing film. Next, the resist pattern was stripped and cleaned by washing with sulfuric acid and hydrogen peroxide.

[0107] Next, the absorbing film was patterned using an etching device to obtain an absorbing film pattern. Chlorine was used as the etching gas, and the gas pressure was set to 5 mTorr, the ICP power to 400 W, and the bias power to 40 W. Overetching was performed by 50%. At this time, the damage amount of the adhesion layer pattern was 2 nm, and the adhesion layer pattern was lost, but the damage amount of the lower layer pattern was 1 nm, there was no damage to the protective film, and no micro-defects were generated or the lower layer pattern was lost. Next, cleaning was performed by washing with sulfuric acid and hydrogen peroxide.

[0108] In this way, a reflective mask of Example 4 was obtained, which comprises a reflective region formed by stacking a substrate having small thermal expansion due to exposure, a multilayer reflective film, and a protective film, and an absorbing region formed by stacking a substrate having small thermal expansion due to exposure, a multilayer reflective film, a protective film, and an absorbing film. From the evaluation results of Examples 1 to 4, compared with conventional transmission type and reflection type masks, the transmission type and reflection type masks manufactured using the transmission type and reflection type mask blanks of the present embodiment are capable of forming resist patterns having a small minimum resolution pattern dimension of the resist line pattern and a large aspect ratio, and are effective for manufacturing LSIs.

[0109] Although the present invention has been described above in accordance with the present embodiment with respect to the transmission mask blank and the reflective mask blank, and the respective methods for manufacturing the transmission mask and the reflective mask using the same, the above-mentioned embodiments are merely examples for carrying out the present invention, and the present invention is not limited thereto. Furthermore, it is within the scope of the present invention to modify these embodiments and the above-mentioned respective embodiments, and it is self-evident from the above description that various other embodiments are possible within the scope of the present invention. [Industrial Applicability]

[0110] In the present invention, the compositions, film thicknesses, and layer structures of the transmission mask blank and the reflective mask blank, as well as the manufacturing processes and conditions for the transmission mask and the reflective mask using the same are selected within appropriate ranges, and therefore it is possible to provide a transmission mask and a reflective mask on which a fine pattern is formed with high precision, which is suitable for manufacturing logic devices of 28 nm or less, or memory devices of 30 nm or less. [Explanation of symbols]

[0111] 10, 20, 30...Transmissive mask blanks 40 Reflective mask blank 11, 21, 31: Substrate transparent to the exposure wavelength 41...Substrate with small thermal expansion due to exposure 12, 22, 32... Light-shielding film 42...Absorption film 13, 23, 33, 43...Hard mask 33a, 43a...lower layer 33b, 43b... Adhesion layer 24, 34...Semi-transparent film 44...Multilayer reflective film 25, 35, 45...protective film 16, 26, 36, 46...resist pattern (first resist pattern) 27, 37: resist pattern (second resist pattern) 100, 200, 300...Transmissive mask 400···Reflective mask

Claims

1. A mask blank used in the manufacture of a transmission type mask or a reflection type mask, A substrate; a thin film formed on the substrate, the thin film having resistance to oxygen-containing chlorine-based gas etching and capable of being etched by a fluorine-based gas or an oxygen-free chlorine-based gas; a hard mask formed on the thin film, the hard mask having resistance to etching with a fluorine-based gas or an oxygen-free chlorine-based gas and capable of being etched with an oxygen-containing chlorine-based gas; The hard mask is a mask blank comprising a plurality of layers, and has, at least on its outermost surface, an adhesion layer containing at least one or more metal elements selected from titanium, niobium, hafnium, beryllium, and aluminum, and further has, on the substrate side of the adhesion layer, a lower layer containing chromium.

2. The mask blank described in claim 1, characterized in that the lower layer contains only two elements, chromium and nitrogen.

3. A mask blank as described in claim 1 or claim 2, characterized in that the adhesion layer contains at least beryllium.

4. 4. The mask blank according to claim 1, wherein the adhesion layer has a thickness in the range of 1 nm to 10 nm.

5. 5. The mask blank according to claim 1, wherein the lower layer has a thickness in the range of 1 nm to 19 nm.

6. 6. The mask blank according to claim 1, wherein the hard mask has a thickness in the range of 2 nm to 20 nm.

7. 7. The mask blank according to claim 1, wherein the hard mask has a thickness in the range of 2 nm to 7 nm.

8. the thin film contains at least one compound selected from a silicon compound, a tantalum compound, an indium compound, and a tin compound; The silicon compound contains silicon and one or more elements selected from nitrogen, boron, oxygen, carbon, and molybdenum, The tantalum compound contains tantalum and one or more elements selected from silicon, nitrogen, boron, oxygen, carbon, and molybdenum, The indium compound contains indium and one or more elements selected from nitrogen, boron, oxygen, and carbon, 8. The mask blank according to claim 1, wherein the tin compound contains tin and one or more elements selected from the group consisting of nitrogen, boron, oxygen, and carbon.

9. the thin film contains at least one compound selected from a silicon compound, a tantalum compound, an indium compound, and a tin compound; The silicon compound contains silicon, oxygen, and one or more elements selected from nitrogen, boron, carbon, and molybdenum, The tantalum compound contains tantalum and one or more elements selected from nitrogen, boron, oxygen, carbon, and molybdenum, and does not contain silicon; The indium compound contains indium and one or more elements selected from nitrogen, boron, oxygen, and carbon, and contains indium in an element ratio of the entire indium compound in a range of 35 atomic % to 55 atomic %; 8. The mask blank according to claim 1, wherein the tin compound contains tin and one or more elements selected from the group consisting of nitrogen, boron, and carbon.

10. the thin film contains at least one compound selected from a silicon compound, a tantalum compound, and an indium compound; The silicon compound contains silicon, oxygen, and one or more elements selected from nitrogen, boron, carbon, and molybdenum, The tantalum compound contains tantalum and one or more elements selected from nitrogen, boron, oxygen, carbon, and molybdenum, and does not contain silicon; 8. The mask blank according to claim 1, wherein the indium compound contains indium and one or more elements selected from nitrogen, boron, oxygen, and carbon, and the indium compound contains indium in an element ratio ranging from 35 atomic % to 55 atomic % inclusive in the entire indium compound.

11. the mask blank is a transmission mask blank used in the manufacture of a transmission mask, 11. The mask blank according to claim 1, wherein the thin film is a light-shielding film having an optical density of 1 or more for light having a wavelength of 193 nm.

12. the mask blank is a transmission mask blank used in the manufacture of a transmission mask, The mask blank according to claim 11, characterized in that it has a semi-transparent film between the substrate and the light-shielding film, which has resistance to oxygen-containing chlorine-based gas etching, can be etched by a fluorine-based gas or an oxygen-free chlorine-based gas, and inverts the phase difference of light with a wavelength of 193 nm by a desired amount.

13. the mask blank is a transmission mask blank used in the manufacture of a transmission mask, 13. The mask blank according to claim 1, further comprising a protective film between the substrate and the thin film, the protective film having resistance to etching with a fluorine-based gas or an oxygen-free chlorine-based gas and capable of being etched with an oxygen-containing chlorine-based gas or an oxygen-based gas.

14. the mask blank is a transmission mask blank used in the manufacture of a transmission mask, 14. The mask blank according to claim 13, wherein the protective film contains one or more elements selected from the group consisting of chromium, ruthenium, niobium, and aluminum.

15. the mask blank is a transmission mask blank used in the manufacture of a transmission mask, 14. The mask blank according to claim 13, wherein the protective film contains one or more elements selected from the group consisting of ruthenium, niobium, and aluminum.

16. The mask blank is a reflective mask blank used in the manufacture of a reflective mask, The thin film is an absorbing film that absorbs light with a wavelength of 13.5 nm, 11. The mask blank according to claim 1, further comprising a multilayer reflective film between the substrate and the absorbing film, the multilayer reflective film having a multilayer structure and reflecting light with a wavelength of 13.5 nm.

17. A method for manufacturing a transmission mask or a reflective mask using the mask blank according to any one of claims 1 to 16, comprising the steps of: forming a resist pattern on the hard mask of the mask blank; forming a hard mask pattern by etching the hard mask with an oxygen-containing chlorine-based gas using the resist pattern as a mask; and etching the thin film with a fluorine-based gas or an oxygen-free chlorine-based gas using the hard mask pattern as a mask to form a thin film pattern.

Images