WO2013136881A1 - マスクブランク、及び転写用マスクの製造方法 - Google Patents

マスクブランク、及び転写用マスクの製造方法 Download PDF

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Publication number
WO2013136881A1
WO2013136881A1 PCT/JP2013/052801 JP2013052801W WO2013136881A1 WO 2013136881 A1 WO2013136881 A1 WO 2013136881A1 JP 2013052801 W JP2013052801 W JP 2013052801W WO 2013136881 A1 WO2013136881 A1 WO 2013136881A1
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Prior art keywords
mask blank
thin film
mask
etching
tantalum
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English (en)
French (fr)
Japanese (ja)
Inventor
鈴木　寿幸
山田　剛之
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Hoya Corp
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Hoya Corp
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Priority to US14/384,953 priority Critical patent/US20150079502A1/en
Application filed by Hoya Corp filed Critical Hoya Corp
Priority to KR1020147023809A priority patent/KR101862165B1/ko
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F1/00—Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
    • G03F1/38—Masks having auxiliary features, e.g. special coatings or marks for alignment or testing; Preparation thereof
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F1/00—Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
    • G03F1/22—Masks or mask blanks for imaging by radiation of 100nm or shorter wavelength, e.g. X-ray masks, extreme ultraviolet [EUV] masks; Preparation thereof

Definitions

  • the present invention relates to a mask blank and a method for manufacturing a transfer mask.
  • a fine pattern is formed using a photolithography method.
  • a transfer mask is used in the fine pattern transfer process when the photolithography method is performed.
  • This transfer mask is generally manufactured by forming a desired fine pattern on a light shielding film of a mask blank as an intermediate. Therefore, the characteristics of the light-shielding film formed on the mask blank as an intermediate substantially affect the performance of the transfer mask.
  • Patent Document 1 a Ta metal film has an extinction coefficient (light absorption rate) higher than that of a Cr metal film with respect to light having a wavelength of 193 nm used in ArF excimer laser exposure. It is disclosed.
  • oxygen-containing chlorine-based dry Etching (Cl + O) -based) does not substantially etch, and a light-shielding layer of a metal film that can be etched by oxygen-free chlorine-based dry etching (Cl-based) and fluorine-based dry etching (F-based), oxygen Metal that is not substantially etched by non-containing chlorine-based dry etching (Cl-based) and that can be etched by at least one of oxygen-containing chlorine-based dry etching ((Cl + O) -based) or fluorine-based dry etching (F-based)
  • a transfer mask blank comprising a compound film antireflection layer is disclosed.
  • the mask blank is usually cleaned with a cleaning liquid containing cleaning water or a surfactant for the purpose of removing oil droplets or particles present on the surface of the film.
  • surface treatment for reducing the surface energy of the mask blank may be performed before applying the resist film.
  • alkylsilylation of the surface of the mask blank with hexamethyldisilazane (HMDS) or other organic silicon-based surface treatment agent is performed.
  • the defect inspection of the mask blank is performed before the resist film is formed on the surface or after the resist film is formed. Then, a mask for transfer is manufactured by etching a mask blank that satisfies a desired specification (quality).
  • a mask for transfer is manufactured by etching a mask blank that satisfies a desired specification (quality).
  • the resist film formed on the mask blank is drawn, developed, and rinsed to form a resist pattern, and then the resist pattern is used as a mask to form an antireflection layer. Etching to form an antireflection layer pattern.
  • an oxygen-containing chlorine-based gas or a fluorine-based gas is used.
  • the light shielding layer is etched to form a light shielding layer pattern.
  • an oxygen-free chlorine-based gas is used.
  • the transfer mask is completed by removing the resist film.
  • the completed transfer mask is inspected by a mask defect inspection apparatus for black defects and white defects, and if a defect is found, the defect is corrected using a correction technique such as EB irradiation.
  • This micro black defect has a spot-like size on the surface of the substrate of 20 to 100 nm and a height corresponding to the thickness of the thin film, and a transfer mask having a DRAM half pitch of 32 nm or more is manufactured according to the semiconductor design rule. It is recognized for the first time. Such micro black defects are fatal defects when manufacturing semiconductor devices and must be removed and corrected. However, if the number of defects exceeds 50, the burden of defect correction is large, and defect correction is practical. Is difficult.
  • the present invention has been made in view of the above-described circumstances, and an object thereof is to provide a mask blank that can suppress the occurrence of black defects in a transfer mask.
  • the present inventors investigated the cause of the above-mentioned fine black defect of the mask, and found that the latent defect that is not detected by the defect inspection of the mask blank is one factor. And it turned out that the defect of the above-mentioned latent mask blank has generate
  • a mask blank having a structure in which a thin film is formed on a substrate The thin film is made of a material containing one or more elements selected from tantalum, tungsten, zirconium, hafnium, vanadium, niobium, nickel, titanium, palladium, molybdenum and silicon,
  • TOF-SIMS time-of-flight secondary ion mass spectrometry
  • a primary ion species of Bi 3 ++ a primary acceleration voltage of 30 kV, and a primary ion current of 3.0 nA
  • the normalized secondary ion intensity of at least one or more ions selected from calcium ions, magnesium ions and aluminum ions is 1.0 ⁇ 10 ⁇ 3 or less.
  • the normalized secondary ion intensity referred to in this specification is the total number of secondary ions emitted from the surface of the thin film when the surface is irradiated with the primary ions and counted in the measurement range.
  • the numerical value calculated by dividing the number of target ions (calcium ions, etc.).
  • At least one or more ions selected from the calcium ions, magnesium ions and aluminum ions are etched when a pattern is formed on the thin film by dry etching using an etching gas containing fluorine or an etching gas containing chlorine.
  • etching gas containing fluorine or an etching gas containing chlorine is a substance that causes an inhibition.
  • the substrate is a glass substrate having transparency to exposure light
  • (Configuration 9) A multilayer reflective film having a function of reflecting exposure light between the substrate and the thin film, 9.
  • Configuration 10 A method for manufacturing a transfer mask, comprising a step of forming a transfer pattern by dry etching on the thin film of the mask blank according to any one of configurations 1 to 9.
  • Configuration 11 The method for manufacturing a transfer mask according to Configuration 10, wherein the dry etching uses an etching gas containing fluorine or an etching gas containing chlorine.
  • normalized secondary ions of at least one or more ions selected from calcium ions, magnesium ions, and aluminum ions when the surface of the thin film is measured by time-of-flight secondary ion mass spectrometry under predetermined measurement conditions By using a mask blank having an intensity of 1.0 ⁇ 10 ⁇ 3 or less, it is possible to suppress the occurrence of black defects when a pattern is formed on a thin film by etching to produce a transfer mask.
  • Two types of mask blanks were prepared in order to investigate the cause of micro black defects in the transfer mask.
  • One is a mask blank on which a thin film made of a tantalum-based material is formed, and the other is a mask blank on which a thin film made of a chrome-based material is formed.
  • a mask blank in which a thin film made of a tantalum-based material is formed, a light-shielding layer (film thickness: 42 nm) consisting essentially of tantalum and nitrogen on a light-transmitting substrate, and substantially consisting of tantalum and oxygen
  • a binary mask blank hereinafter referred to as a tantalum-based mask blank, which is referred to as a tantalum-based mask
  • a tantalum-based mask having a laminated structure of a TaO antireflection layer (thickness: 9 nm) was prepared.
  • a CrCON film substantially composed of chromium, oxygen, nitrogen, and carbon is formed on a translucent substrate, and substantially chromium.
  • a light-shielding layer of a CrON film (thickness: 16.5 nm) made of Cr, oxygen and nitrogen, and a CrCON antireflection layer (thickness: 14 nm) consisting essentially of chromium, oxygen, nitrogen and carbon
  • a binary mask blank having a structure hereinafter referred to as a chrome mask blank, and the mask is referred to as a chrome mask
  • the two types of binary mask blanks described above are surface active.
  • the alkaline cleaning liquid containing the agent was supplied to the mask blank surface to perform surface cleaning.
  • the defect inspection was performed with the mask blank defect inspection apparatus (M1350: product made from a Lasertec company). As a result, in any mask blank, defects such as particles and pinholes could not be confirmed on the surface of the thin film.
  • a transfer mask was prepared using two types of mask blanks subjected to the same surface cleaning as described above.
  • a resist pattern is formed on the mask blank surface, dry etching using a fluorine-based (CF 4 ) gas is performed using the resist pattern as a mask, the antireflection layer is patterned, and then the antireflection layer is formed.
  • CF 4 fluorine-based
  • CF 4 chlorine-based
  • the resist pattern was removed to produce a transfer mask (tantalum-based mask).
  • a resist pattern is formed on the mask blank surface, dry etching using a mixed gas of chlorine-based (Cl 2 ) gas and oxygen (O 2 ) gas is performed using the resist pattern as a mask, The antireflection layer and the light shielding layer were patterned, and finally the resist pattern was removed to prepare a transfer mask (chrome mask).
  • the two obtained transfer masks were subjected to defect inspection using a mask defect inspection apparatus (manufactured by KLA-Tencor). As a result, it was confirmed that a large number (more than 50) of micro black defects existed in the tantalum mask. On the other hand, almost no micro black defects were found in the chromium-based mask (the number of defects that can be corrected in practice with the mask defect correction technology). The minute black defects in the tantalum mask were confirmed in the same manner even when UV treatment, ozone treatment, or heat treatment was performed for the purpose of removing the dirt on the mask blank before forming the resist film.
  • the minute black defects of the tantalum mask were confirmed in the same manner even when the antireflection layer and the light shielding layer were patterned at once by dry etching using a fluorine (CF 4 ) gas.
  • the fine black defects of the tantalum mask detected by the defect inspection were observed in a cross-section in a bright field using a scanning transmission electron microscope (STEM).
  • STEM scanning transmission electron microscope
  • a platinum alloy was coated on the entire surface of the translucent substrate on which the thin film pattern was formed.
  • the micro black defect had a height substantially equal to the film thickness of the laminated film of the light shielding layer and the antireflection layer.
  • the micro black defect is a laminated structure in which a material that is thought to be a surface oxide having a thickness of 5 to 10 nm is laminated on a nucleus having a width of about 23 nm and a height of about 43 nm ( (See FIG. 1).
  • a substance that inhibits etching adheres to the surface of a thin film made of a tantalum-based material in a tantalum-based mask blank in a state (thickness) that is difficult to detect even with the latest mask blank defect inspection equipment. This may have caused the occurrence of micro black defects.
  • calcium (Ca), aluminum (Al), magnesium (Mg), or a compound thereof was considered as an etching inhibiting factor.
  • These substances include calcium fluoride (boiling point: 2500 ° C.), magnesium fluoride (boiling point: 1260 ° C.), aluminum fluoride (boiling point: 1275 ° C.) during dry etching of a thin film with a fluorine-based gas or a chlorine-based gas. This is because compounds such as calcium chloride (boiling point: 1600 ° C.) and magnesium chloride (boiling point: 1412 ° C.) are produced, and these compounds become etching inhibitors.
  • the etching inhibitor is the reason why a large difference in the number of micro black defects generated when the transfer mask is produced between the tantalum mask blank and the chromium mask blank. Therefore, the existence of an etching inhibiting factor on the surface of the mask blank that was not detected by the mask blank defect inspection apparatus was examined. Specifically, the above-mentioned two types of mask blanks (tantalum-based mask blanks and chromium-based mask blanks) that were surface-cleaned with an alkaline cleaning liquid were prepared for each five sheets. Then, the surface of the thin film in each mask blank was analyzed by time-of-flight secondary ion mass spectrometry (TOF-SIMS).
  • TOF-SIMS time-of-flight secondary ion mass spectrometry
  • the TOF-SIMS measurement conditions at this time are as follows: the primary ion species is Bi 3 ++ , the primary acceleration voltage is 30 kV, the primary ion current is 3.0 nA, and the primary ion irradiation region is an inner region of a square having a side of 200 ⁇ m.
  • the secondary ion measurement range was 0.5 to 3000 m / z, and the conditions were the same for all mask blanks.
  • any tantalum-based mask blank at least one of calcium, magnesium, and aluminum ions, which are substances that inhibit etching, was detected on the surface of the thin film.
  • the normalized secondary ionic strength was higher than 1.0 ⁇ 10 ⁇ 3 .
  • the etching-inhibiting factor substance presumed to be attached to the surface of the thin film of the tantalum-based mask blank is difficult to detect with a mask blank defect inspection apparatus because it is thin. Although it is not impossible to scan the entire surface of the thin film with an atomic force microscope (AFM) and identify the location where the etching inhibitory substance is attached, it takes an enormous amount of time for detection. For this reason, a thin film made of a chromium-based material with a low risk of adhesion of an etching-inhibiting substance on the thin film of a tantalum-based mask blank (tantalum-based film) that has been surface-cleaned with a cleaning solution is formed in two layers of 100 nm thickness Laminated.
  • AFM atomic force microscope
  • the chromium-based mask blank a thin film made of a chromium-based material was laminated, and a defect inspection was performed using a mask blank defect inspection apparatus. Regarding the detected convex defect, the cross-sectional observation with STEM and the element identification with EDX were performed in the same manner, but no similar layer was found. From the results of the above TOF-SIMS and STEM, the reason why there is a large difference in the number of micro black defects generated when a transfer mask is produced between a tantalum mask blank and a chromium mask blank is the etching inhibition. It became clear that this was due to the difference in the number of adherent substances.
  • the light shielding layer (TaN) is patterned by dry etching using a chlorine-based gas. At this time, since the etching rate of TaO with respect to the chlorine-based gas is significantly smaller than that of TaN, the rest of the antireflection layer serves as a mask, and a part of the light shielding layer (TaN) remains without being etched. Thereby, nuclei of minute black defects are formed (FIG. 3D).
  • the generation mechanism of the micro black defect has been described with respect to calcium, magnesium and aluminum, which are etching inhibiting substances, may react with fluorine or chlorine contained in the etching gas to form an etching inhibiting substance. Therefore, it is considered that minute black defects are generated by the same mechanism as described above.
  • calcium or magnesium etching inhibiting substances react with the chlorine gas to form calcium chloride or magnesium chloride when dry etching is performed with the chlorine gas. Since these chlorides also have a high boiling point and are difficult to dry etch, they can be etching inhibitors.
  • the etching inhibiting factor is a material that reacts with fluorine (F), chlorine (Cl), or the like contained in a dry etching gas to generate an etching inhibiting substance.
  • the mask blank of the present invention is a mask blank having a structure in which a thin film is formed on a substrate, and the thin film includes tantalum, tungsten, zirconium, hafnium, vanadium, niobium, nickel, titanium, palladium.
  • a time-of-flight secondary ion made of a material containing one or more elements selected from molybdenum and silicon, with the primary ion species being Bi 3 ++ , the primary acceleration voltage being 30 kV, and the primary ion current being 3.0 nA
  • the normalized secondary ion intensity of at least one or more ions selected from calcium ions, magnesium ions and aluminum ions is 1.0 ⁇ 10 ⁇ It is characterized by being 3 or less.
  • the surface of the thin film is measured by TOF-SIMS in order to suppress the number of micro black defects generated to less than 50 when the transfer mask is manufactured.
  • the normalized secondary ion intensity of at least one or more ions selected from calcium ions, magnesium ions and aluminum ions must be at least 1.0 ⁇ 10 ⁇ 3 or less.
  • calcium ions, magnesium ions, and aluminum when the surface of the thin film is measured by TOF-SIMS.
  • the normalized secondary ionic strength of at least one or more ions selected from ions is preferably at least 5.0 ⁇ 10 ⁇ 4 or less. More preferably, the normalized secondary ion intensity of at least one or more ions selected from calcium ions, magnesium ions and aluminum ions when the surface of the thin film is measured by TOF-SIMS is at least 1.0 ⁇ 10 ⁇ 4. It is as follows.
  • the primary ion irradiation region is an inner region of a rectangle having a side of 200 ⁇ m.
  • the measurement range of secondary ions is preferably 0.5 to 3000 m / z.
  • the mask blank is a mask blank having a structure in which a thin film is formed on a substrate, and the thin film includes tantalum, tungsten, zirconium, hafnium, vanadium, niobium, nickel, titanium, palladium, molybdenum, and silicon.
  • a time-of-flight secondary ion mass spectrometry method comprising a material containing one or more elements selected from the group consisting of Bi 3 ++ , a primary acceleration voltage of 30 kV, and a primary ion current of 3.0 nA.
  • the normalized secondary ion intensity of calcium ion, magnesium ion and aluminum ion when the surface of the thin film is measured by TOF-SIMS is 1.0 ⁇ 10 ⁇ 3 or less. Further, the normalized secondary ion intensity of calcium ions, magnesium ions and aluminum ions when the surface of the thin film is measured by TOF-SIMS is preferably 5.0 ⁇ 10 ⁇ 4 or less, and 1.0 ⁇ 10 6 -4 or less is particularly preferable.
  • the thin film formed on the substrate includes tantalum (Ta), tungsten (W), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), nickel (Ni), titanium. It is preferably formed of a material containing one or more metals selected from (Ti), palladium (Pd), molybdenum (Mo), and silicon (Si). From the viewpoint of controlling optical characteristics and etching characteristics, it is preferable that the above materials contain oxygen, nitrogen, carbon, boron, hydrogen, fluorine, or the like.
  • a thin film made of these materials forms a transfer pattern corresponding to the generation of DRAM half pitch 32 nm or later, which is a semiconductor design rule, by dry etching using a fluorine-based gas or a chlorine-based gas containing substantially no oxygen.
  • a fluorine-based gas or a chlorine-based gas containing substantially no oxygen is possible.
  • SRAF Sub-Resolution Assist Feature
  • Examples of the etching gas containing fluorine (fluorine-based gas) include CHF 3 , CF 4 , SF 6 , C 2 F 6 , and C 4 F 8 .
  • Examples of the etching gas containing chlorine (chlorine-based gas) include Cl 2 , SiCl 4 , CHCl 3 , CH 2 Cl 2 , and CCl 4 .
  • As the dry etching gas a mixed gas in which a gas such as He, H 2 , Ar, C 2 H 4 or the like is added in addition to the fluorine-based gas and the chlorine-based gas can be used.
  • anisotropic dry etching can be easily controlled, and there is an excellent effect that the verticality of the side wall of the pattern formed on the thin film can be increased.
  • anisotropic dry etching etching in the pattern side wall direction is suppressed. Therefore, if there is an etching inhibiting substance such as calcium or an etching inhibiting substance generated due to the etching on the thin film, the dry etching is performed. Will be difficult to remove.
  • the etching gas used when dry etching for forming a pattern on a thin film made of a tantalum-based material of the tantalum-based mask blank was a fluorine-based gas and a chlorine-based gas substantially containing no oxygen. It was. Therefore, the tendency of ion-based dry etching is strong, and the etching-inhibiting substance is difficult to remove.
  • the mask blanks listed above are all made of a material capable of ion-based dry etching. It can be said that micro black defects are likely to occur during etching.
  • the etching gas used when dry etching for forming a pattern on the thin film made of the chromium-based material of the chromium-based mask blank was a mixed gas of chlorine-based gas and oxygen gas. Therefore, the tendency of radical-based dry etching is strong, and etching inhibitors are relatively easily removed. This can also be cited as one of the reasons why the number of micro black defects generated is small when a transfer mask is produced from a chromium-based mask blank.
  • the mask blank thin film is preferably provided to form a thin film pattern by dry etching using an etching gas containing fluorine or an etching gas containing chlorine.
  • an etching gas containing chlorine that does not substantially contain oxygen is preferable.
  • the etching gas containing chlorine which does not substantially contain oxygen refers to an etching gas having an oxygen concentration of at least 5% by volume or less, more preferably 3% by volume or less.
  • the thin film is more preferably formed with a pattern by ion-based etching.
  • the material of the thin film of the mask blank is preferably a material containing tantalum.
  • the surface layer of the thin film is formed with an oxide layer containing more oxygen than the portion other than the surface layer.
  • the surface layer of a tantalum nitride film (TaN film) or a tantalum film (Ta film) has an oxide layer (TaO, particularly an oxygen content of 60 at% or more, and a Ta 2 O 5 bond abundance ratio.
  • a thin film in which a high highly oxidized layer is formed.
  • Many hydroxyl groups (OH groups) exist on the surface of the surface layer of the oxide layer containing tantalum. When many hydroxyl groups are present on the surface, an etching inhibiting factor such as calcium is likely to adhere for the reason described later, so that the effects of the present invention can be obtained more.
  • the thin film made of a material containing tantalum in the mask blank has a laminated structure of a lower layer and an upper layer from the substrate side, and the upper layer preferably contains oxygen. More preferably, it is a laminated film in which a lower layer made of a material containing tantalum and nitrogen and an upper layer made of a material containing tantalum and oxygen are laminated. In this case, a high oxide layer containing a larger amount of oxygen (for example, oxygen content of 60 at% or more) than that in the other upper layers in the upper surface layer and having a high ratio of Ta 2 O 5 bonds is formed. May be.
  • An oxide layer or a tantalum oxide film containing tantalum tends to have a high proportion of hydroxyl groups (OH groups) on the surface thereof.
  • OH groups hydroxyl groups
  • an etching inhibiting factor such as calcium is likely to adhere for the reason described later, so that the effects of the present invention can be obtained more.
  • examples of the material containing tantalum and nitrogen include TaN, TaBN, TaCN, TaBCN, and the like, but other elements other than tantalum and nitrogen may be included.
  • examples of the material containing tantalum and oxygen include TaO, TaBO, TaCO, TaBCO, TaON, TaBON, TaCON, TaBCON, and the like, but other elements other than tantalum and oxygen may be included.
  • the thin film made of a material containing tantalum in the mask blank may have a structure in which a lower layer made of only tantalum and an upper layer made of a material containing tantalum and oxygen are laminated from the substrate side.
  • a material consisting only of tantalum, which does not contain oxygen and nitrogen is a material whose etching rate in dry etching using an etching gas containing chlorine that does not substantially contain oxygen contains tantalum and nitrogen. Bigger than The upper layer made of a material containing tantalum and oxygen is the same as the upper layer.
  • the thin film made of a material containing tantalum in the mask blank may have a structure in which a lower layer made of a material containing tantalum and silicon and an upper layer made of a material containing tantalum and oxygen are laminated from the substrate side.
  • a material in which silicon is contained in tantalum can make the crystal state in the material more microcrystalline or amorphous than a material containing tantalum and nitrogen. Further, by adding silicon to tantalum, the optical density (extinction coefficient) with respect to exposure light can be made higher than that of a material made of tantalum alone.
  • the etching rate in dry etching using an etching gas containing chlorine that does not substantially contain oxygen can be made larger than that of a material made of tantalum alone.
  • the etching rate increases as the content of silicon in the material increases, and the mixing ratio of tantalum (Ta) and silicon (Si) in the material increases.
  • the ratio [%] of the tantalum content [atomic%] to the total content [atomic%] of tantalum and silicon in the material constituting the lower layer is preferably 20% or more, more than 30% More preferably, it is more preferably 33% or more.
  • the ratio [%] of the tantalum content [atomic%] to the total content [atomic%] of tantalum and silicon in the material constituting the lower layer is preferably 95% or less, and more preferably 90% or less. More preferably, it is 85% or less.
  • the upper layer made of a material containing tantalum and oxygen is the same as the upper layer.
  • etching inhibiting substances such as calcium, magnesium, and aluminum to adhere to the surface of the thin film of the mask blank
  • a detergent used when cleaning the surface of the thin film.
  • the surfactant used for cleaning the surface of the mask blank includes calcium ions (Ca 2+ ), magnesium ions (Mg 2+ ), aluminum ions (Al 3+ ), and aluminum hydroxide ions (impurities) depending on the production method and pH.
  • Al (OH) 4 ⁇ ) may be included, and these are ionized and are difficult to remove. It is considered that calcium and the like detected by the TOF-SIMS were contained in the surfactant contained in the cleaning solution used this time.
  • a large number of hydroxyl groups (OH groups) are present on the surface of the tantalum mask blank, and calcium ions (Ca 2+ ) and magnesium ions (Mg 2+ ) contained in the cleaning liquid are attracted to the hydroxyl groups (FIG. 4A).
  • the liquid covering the surface of the mask blank rapidly changes from alkaline (pH 10) to neutral (around pH 7) when rinsing with pure water for washing away the cleaning liquid.
  • Calcium ions and magnesium ions attracted to the surface become calcium hydroxide (Ca (OH) 2 ) and magnesium hydroxide (Mg (OH) 2 ) and are easily deposited on the film surface (FIG. 4B). It is considered that this calcium hydroxide and magnesium hydroxide became etching inhibiting substances on the mask blank surface.
  • the substrate is a glass substrate that is transparent to exposure light, and the thin film is used to form a transfer pattern when a transfer mask is produced from the mask blank.
  • the mask blank having such a configuration is also referred to as a transmission mask blank.
  • a transfer mask manufactured from the transmission mask blank is also referred to as a transmission mask.
  • examples of a thin film for forming a transfer pattern include a light-shielding film having a function of shielding exposure light, and suppressing reflection on the surface in order to suppress multiple reflection from the transfer target.
  • Examples thereof include an antireflection film having a function, and a phase shift film having a function of generating a predetermined transmittance and a predetermined phase difference with respect to exposure light in order to improve the resolution of the pattern.
  • Examples of the thin film for forming the transfer pattern include a semi-transmissive film that generates a predetermined transmittance with respect to exposure light but does not generate a phase difference that causes a phase shift effect.
  • a mask blank having such a semi-transmissive film is mainly used when manufacturing an enhancer type phase shift mask.
  • These thin films may be a single layer film or a laminated film in which a plurality of these films are laminated.
  • ArF excimer laser light, KrF excimer laser light, or the like is applied as exposure light to a transfer mask manufactured from a mask blank provided with a thin film for forming these transfer patterns.
  • the mask blank includes a multilayer reflective film having a function of reflecting exposure light between the substrate and the thin film, and the thin film is used to form a transfer pattern when a transfer mask is produced from the mask blank. It is preferable that Such a mask blank is also referred to as a reflective mask blank.
  • a transfer mask manufactured from the reflective mask blank is also referred to as a reflective mask.
  • examples of a thin film for forming a transfer pattern include an absorber film having a function of absorbing exposure light, a reflection reducing film for reducing exposure light reflection, and the patterning of the above-described absorber film. Examples include a buffer layer for preventing etching damage to the multilayer reflective film.
  • the transfer mask of the present invention includes the reflective mask described above.
  • EUV light is light (electromagnetic wave) having a wavelength between 0.1 nm and 100 nm, but light (electromagnetic wave) having a wavelength of 13 nm to 14 nm is particularly used.
  • a silicon film (Si film, film thickness 4.2 nm) and a molybdenum film (Mo film, film thickness 2.8 nm) are defined as one period, and this is a plurality of periods ( 20 cycles to 60 cycles, preferably around 40 cycles.)
  • a laminated film structure is often used.
  • a protective film for example, Ru, RuNb, RuZr, RuY, RuMo, etc.
  • Ru, RuNb, RuZr, RuY, RuMo, etc. that protects the multilayer reflective film may be provided between the multilayer reflective film and the absorber film or the buffer layer.
  • an etching mask film (or hard mask film) that functions as an etching mask (hard mask) when the lower layer film is etched may be provided in addition to the above-described thin film serving as the transfer pattern.
  • a thin film to be a transfer pattern may be a laminated film, and an etching mask (hard mask) may be provided as a part of the laminated film.
  • the substrate may be any material that transmits exposure light, for example, synthetic quartz glass.
  • any material that can prevent thermal expansion due to absorption of exposure light may be used.
  • the transfer mask is preferably manufactured by a manufacturing method including a step of forming a transfer pattern on the thin film of the mask blank by dry etching. Further, it is more preferable to use an etching gas containing fluorine or an etching gas containing chlorine for the dry etching in the method for manufacturing the transfer mask.
  • the substances inhibiting the etching include manganese, in addition to the substances listed above. There are iron and nickel. For this reason, in the mask blank described above, by the time-of-flight secondary ion mass spectrometry (TOF-SIMS) using the measurement conditions of the primary ion species Bi 3 ++ , the primary acceleration voltage 30 kV, and the primary ion current 3.0 nA.
  • TOF-SIMS time-of-flight secondary ion mass spectrometry
  • the normalized secondary ion intensity of at least one or more ions selected from manganese ions, iron ions, and nickel ions when the surface of the thin film is measured is preferably 1.0 ⁇ 10 ⁇ 3 or less. Further, the normalized secondary ionic strength is more preferably 5.0 ⁇ 10 ⁇ 4 or less, and particularly preferably 1.0 ⁇ 10 ⁇ 4 or less.
  • an alkaline cleaning liquid containing a surfactant which is performed after the thin film is formed on the substrate, is used as a major factor for the above-described etching inhibiting substances to adhere to the surface of the mask blank thin film.
  • an etching inhibiting substance such as calcium, magnesium, aluminum or the like having a detection lower limit value or less (eg, DI water).
  • the thin film of the mask blank After cleaning the surface of the thin film of the mask blank using a plurality of cleaning liquids having different concentrations of etching inhibiting factors, the thin film was dry etched to verify the number of micro black defects generated. As a result, it was confirmed that when the concentration of the etching inhibitory substance or the like in the cleaning liquid was 0.3 ppb or less, the number of minute black defects generated could be suppressed to a level that is not problematic in practice. From the above, it is preferable to use a cleaning liquid having a concentration of 0.3 ppb or less for the etching-inhibiting substance or the like for the surface cleaning performed on the mask blank thin film.
  • the mask blank thin film is formed of a material having low adhesion to the resist film (particularly, a material containing Si)
  • the mask blank is used to prevent the fine pattern formed on the resist film from peeling off or falling down.
  • a treatment for reducing the surface energy is performed.
  • a surface treatment liquid for alkylsilylating the surface of the mask blank for example, hexamethyldisilazane (HMDS) or other organic silicon type surface treatment liquid is used.
  • HMDS hexamethyldisilazane
  • the concentration of the etching inhibition factor or the like is not more than the detection lower limit value.
  • the mask blank of the present invention can be manufactured even if the concentration of the etching inhibiting factor contained in the surface treatment liquid is 0.3 ppb or less.
  • the concentration of the etching inhibitory factor contained in each of the above processing solutions is determined by inductively coupled plasma emission spectroscopy (ICP-MS) for the processing solution immediately before being supplied to the surface of the mask blank (ICP-MS).
  • ICP-MS inductively coupled plasma emission spectroscopy
  • elements can be specified, but it is difficult to specify the bonding state between the elements. Therefore, for example, the detected value of the calcium concentration in the liquid is a concentration calculated by the total amount of calcium and calcium compounds (the same applies to magnesium and aluminum).
  • Example 1 A plurality of synthetic quartz glass substrates (about 152.1 mm ⁇ about 152.1 mm ⁇ about 6.25 mm) whose main surfaces and end surfaces were precisely polished were prepared.
  • a thin film made of a material containing tantalum was formed on the main surface of each glass substrate.
  • a plurality of binary mask blanks for ArF excimer laser exposure corresponding to the semiconductor design rule DRAM half pitch 32 nm were prepared.
  • each mask blank (mask blank A1 to E1) whose surface was cleaned with each cleaning solution was rinsed with DI water (spin cleaning) and then spin-dried.
  • the normalized secondary ion intensity of calcium ions was measured by TOF-SIMS on the surface of each mask blank thin film after spin drying. The results are shown in Table 1.
  • the measurement conditions in the TOF-SIMS are as follows.
  • Secondary ion measurement range 0.5 to 3000 m / z
  • mask blanks A1 to E1 subjected to the same surface cleaning treatment as described above were prepared.
  • a positive chemically amplified resist PRL009: manufactured by Fuji Film Electronics Materials
  • PRL009 manufactured by Fuji Film Electronics Materials
  • drawing, development, and rinsing are performed on the resist film to form a resist pattern on the mask blank surface.
  • dry etching using a fluorine-based (CF 4 ) gas is performed using the resist pattern as a mask.
  • the upper layer pattern is formed by patterning (at this time, part of the lower layer is also etched), and then dry etching using a chlorine-based (Cl 2 ) gas is performed, and the lower layer is patterned using the upper layer pattern as a mask. A lower layer pattern was formed, and finally the resist pattern was removed to prepare transfer masks.
  • the obtained transfer masks were subjected to defect inspection in the transfer pattern formation region (132 mm ⁇ 104 mm) using a mask defect inspection apparatus (manufactured by KLA-Tencor).
  • Table 1 shows the number of black defects detected by each transfer mask.
  • Example 2 and Comparative Example 2 As in the case of Example 1 and Comparative Example 1, a plurality of sheets for ArF excimer laser exposure corresponding to the semiconductor design rule DRAM half-pitch 32 nm having a thin film in which a lower layer of TaN and an upper layer of TaO are laminated from the glass substrate side. A binary mask blank was prepared.
  • the normalized secondary ion intensity of magnesium ions was measured by TOF-SIMS on the surface of each mask blank thin film after spin drying. The results are shown in Table 2. Note that the measurement conditions in TOF-SIMS at this time are the same as those in Example 1 and Comparative Example 1.
  • Example 3 Comparative Example 3
  • a binary mask blank was prepared.
  • each mask blank (mask blanks K1 to P1) whose surface was cleaned with each cleaning solution was rinsed with DI water (spin cleaning) and then spin-dried.
  • the normalized secondary ion intensity of aluminum ions was measured by TOF-SIMS on the surface of each mask blank thin film after spin drying. The results are shown in Table 3. Note that the measurement conditions in TOF-SIMS at this time are the same as those in Example 1 and Comparative Example 1.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Preparing Plates And Mask In Photomechanical Process (AREA)
  • Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
  • Drying Of Semiconductors (AREA)
PCT/JP2013/052801 2012-03-14 2013-02-07 マスクブランク、及び転写用マスクの製造方法 Ceased WO2013136881A1 (ja)

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US14/384,953 US20150079502A1 (en) 2012-03-14 2013-02-02 Mask blank and method of manufacturing a transfer mask
KR1020147023809A KR101862165B1 (ko) 2012-03-14 2013-02-07 마스크 블랭크, 및 전사용 마스크의 제조방법

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180114690A1 (en) * 2015-03-19 2018-04-26 Sharp Kabushiki Kaisha Cleaning method, method for manufacturing semiconductor device, and plasma treatment device

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101862166B1 (ko) * 2012-03-14 2018-05-29 호야 가부시키가이샤 마스크 블랭크, 및 전사용 마스크의 제조방법
JP6301383B2 (ja) * 2015-03-27 2018-03-28 Hoya株式会社 フォトマスクブランク及びこれを用いたフォトマスクの製造方法、並びに表示装置の製造方法
KR102313892B1 (ko) 2016-03-29 2021-10-15 호야 가부시키가이샤 마스크 블랭크, 마스크 블랭크의 제조 방법, 전사용 마스크의 제조 방법 및 반도체 디바이스의 제조 방법
WO2018074512A1 (ja) * 2016-10-21 2018-04-26 Hoya株式会社 反射型マスクブランク、反射型マスクの製造方法、及び半導体装置の製造方法
JP6900872B2 (ja) * 2016-12-26 2021-07-07 信越化学工業株式会社 フォトマスクブランク及びその製造方法
JP6900873B2 (ja) * 2016-12-26 2021-07-07 信越化学工業株式会社 フォトマスクブランク及びその製造方法
US11454876B2 (en) * 2020-12-14 2022-09-27 Applied Materials, Inc. EUV mask blank absorber defect reduction

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003179034A (ja) * 2001-12-12 2003-06-27 Hitachi Ltd 半導体集積回路装置の製造方法
JP2007118002A (ja) * 2005-10-24 2007-05-17 Schott Ag 基板、特にマスク及びマスクブランク用酸不存在洗浄方法
JP2010244075A (ja) * 2010-07-06 2010-10-28 Hoya Corp マスクブランクスの製造方法及び転写マスクの製造方法
JP2011204712A (ja) * 2010-03-24 2011-10-13 Dainippon Screen Mfg Co Ltd 基板処理方法および基板処理装置

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4604292A (en) * 1985-04-26 1986-08-05 Spire Corporation X-ray mask blank process
JP2658966B2 (ja) * 1995-04-20 1997-09-30 日本電気株式会社 フォトマスク及びその製造方法
WO2003065433A1 (fr) * 2002-01-28 2003-08-07 Mitsubishi Chemical Corporation Detergent liquide pour substrat de dispositif semi-conducteur et procede de nettoyage
EP2056333B1 (de) * 2007-10-29 2016-08-24 ION-TOF Technologies GmbH Flüssigmetallionenquelle, Sekundärionenmassenspektrometer, sekundärionenmassenspektrometisches Analyseverfahren sowie deren Verwendungen
US20100294306A1 (en) * 2007-12-04 2010-11-25 Mitsubishi Chemical Corporation Method and solution for cleaning semiconductor device substrate
JP5638769B2 (ja) * 2009-02-04 2014-12-10 Hoya株式会社 反射型マスクブランクの製造方法及び反射型マスクの製造方法
EP2453464A1 (en) * 2009-07-08 2012-05-16 Asahi Glass Company, Limited Euv-lithography reflection-type mask blank
JP4797114B2 (ja) * 2009-10-12 2011-10-19 Ｈｏｙａ株式会社 転写用マスクの製造方法及び半導体デバイスの製造方法
JP4739461B2 (ja) * 2009-10-12 2011-08-03 Ｈｏｙａ株式会社 転写用マスクの製造方法及び半導体デバイスの製造方法
US8524421B2 (en) * 2010-03-30 2013-09-03 Hoya Corporation Mask blank, transfer mask, methods of manufacturing the same and method of manufacturing a semiconductor device
US8435704B2 (en) * 2010-03-30 2013-05-07 Hoya Corporation Mask blank, transfer mask, and methods of manufacturing the same
KR101913431B1 (ko) * 2011-04-06 2018-10-30 호야 가부시키가이샤 마스크 블랭크의 표면 처리 방법, 및 마스크 블랭크의 제조 방법과 마스크의 제조 방법
JP5925543B2 (ja) * 2011-04-06 2016-05-25 Hoya株式会社 マスクブランクの表面処理方法、マスクブランクの製造方法、およびマスクの製造方法
JP5939662B2 (ja) * 2011-09-21 2016-06-22 Hoya株式会社 マスクブランクの製造方法
KR101862166B1 (ko) * 2012-03-14 2018-05-29 호야 가부시키가이샤 마스크 블랭크, 및 전사용 마스크의 제조방법

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003179034A (ja) * 2001-12-12 2003-06-27 Hitachi Ltd 半導体集積回路装置の製造方法
JP2007118002A (ja) * 2005-10-24 2007-05-17 Schott Ag 基板、特にマスク及びマスクブランク用酸不存在洗浄方法
JP2011204712A (ja) * 2010-03-24 2011-10-13 Dainippon Screen Mfg Co Ltd 基板処理方法および基板処理装置
JP2010244075A (ja) * 2010-07-06 2010-10-28 Hoya Corp マスクブランクスの製造方法及び転写マスクの製造方法

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180114690A1 (en) * 2015-03-19 2018-04-26 Sharp Kabushiki Kaisha Cleaning method, method for manufacturing semiconductor device, and plasma treatment device
US10410855B2 (en) * 2015-03-19 2019-09-10 Sharp Kabushiki Kaisha Cleaning method, method for manufacturing semiconductor device, and plasma treatment device

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