JP2012027508A - Mask blank and photomask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mask blank and a photomask reducing obstacles to higher quality of a large-sized mask blank and mask for future FPD.SOLUTION: A mask blank 10 for producing an FPD device comprises a glass substrate 12, a light-transmissive film 14 having light transmissivity through a light in a wavelength region over i line to g line, and a metal silicide-based film, where the metal silicide-based film is a film patterned by wet-etching using an etching liquid as an aqueous solution in which one or more fluorine compounds selected from ammonium hydrogen fluoride, ammonium fluoride and fluoroboronic acid is mixed with an oxidant and where the light-transmissive film 14 is a film formed of a material having etching selectivity for an etching liquid used in wet-etching of a metal silicide-based film.

Description

  The present invention relates to a mask blank and a photomask.

  In recent years, attempts have been made to reduce the number of masks using a gray-tone mask in the field of photomasks (FPD masks) for manufacturing large FPD devices (Non-patent Document 1). The gray tone mask is a photomask having a light shielding portion, a transmission portion, and a gray tone portion on a transparent substrate. The gray tone portion is, for example, a semi-transparent region in which a semi-transparent film (half-transparent film) is formed or a semi-transparent region in which a gray tone pattern is formed, and the function of adjusting the amount of exposure light transmitted. Have As a result, the gray tone portion reduces the amount of light transmitted through the region, reduces the irradiation amount by the region, and reduces the film thickness after development of the photoresist corresponding to the region to a desired value. To control. The gray tone pattern is a pattern having a fine light-shielding pattern and a fine transmissive portion that are less than the resolution limit of a large FPD exposure machine, and is formed by patterning a light-shielding film.

  When the gray tone mask is mounted and used in a large projection apparatus of a mirror projection system or a lens projection system using a lens, the exposure light passing through the gray tone portion does not have a sufficient exposure amount as a whole. Therefore, the positive photoresist exposed through the gray tone portion remains on the substrate only by reducing the film thickness. In other words, the resist can have a difference in solubility in the developer between the portion corresponding to the normal light-shielding portion and the portion corresponding to the gray tone portion, depending on the exposure amount. Therefore, the resist shape after development is, for example, a portion corresponding to a normal light-shielding portion is about 1 μm, a portion corresponding to a gray tone portion is about 0.4 to 0.5 μm, and a portion corresponding to a transmission portion has no resist. Part. Then, the first etching of the substrate to be processed is performed in the portion without the resist, the thin portion of the resist corresponding to the gray tone portion is removed by ashing or the like, and the second etching is performed in this portion, so that one sheet is obtained. The process for two conventional masks is performed with a mask to reduce the number of masks.

  Conventionally, in the field of photomasks (LSI masks) for manufacturing LSIs, it has been proposed to use a light shielding film of metal silicide (such as molybdenum silicide) (Patent Document 1). In Patent Document 1, this light shielding film is proposed as a material suitable for patterning by wet etching.

  Subsequently, with the improvement of dry etching technology, patterning by dry etching has become common in the field of LSI masks in order to achieve high pattern dimensional accuracy. As a light shielding film material that can be patterned by dry etching, a metal silicide light shielding film has been proposed (Patent Document 2). Further, a configuration has been proposed in which an oxidized metal silicide film is formed on a metal silicide film to form a light-shielding film with an antireflection function (Patent Document 3). Thus, in recent years, in the LSI mask, the metal silicide film has been developed as a film dedicated to dry etching, and the development of a film made of a metal silicide-based material suitable for wet etching has progressed since Patent Document 1. Not in.

Conventionally, a configuration in which an etching stopper layer is provided on the surface of a substrate has been proposed in order to accurately set a phase shift amount in an LSI phase shift mask (Patent Documents 4 and 5). In Patent Document 4, the phase shifter film is a film mainly composed of silicon oxide. The etching stopper layer is a film made of a material in which Al ₂ O ₃ is an essential constituent and MgO, ZrO, Ta ₂ O ₃ , or HfO is mixed. In Patent Document 5, the phase shifter film is a film of coated glass. The etching stopper layer is a film mainly composed of hafnium oxide.
Monthly FPD Intelligence, p. 31-35, May 1999 JP 62-218585 A Japanese Examined Patent Publication No. 3-66656 Japanese Examined Patent Publication No. 4-35743 Japanese Patent Laid-Open No. 5-134386 Japanese Patent Laid-Open No. 7-36176

  The LSI mask is a photomask for manufacturing a semiconductor device such as a microprocessor, a semiconductor memory, or a system LSI, and is relatively small at a maximum of about 6 inches square. Therefore, it is often used by being mounted on a reduction projection exposure apparatus using a stepper (shot-step exposure) method. In the LSI mask, monochromatic exposure light is used from the viewpoint of eliminating chromatic aberration due to the lens system and improving the resolution. In recent years, in an LSI mask, the exposure wavelength has been shortened in order to overcome the resolution limit determined by the exposure wavelength. The shortening of the monochromatic exposure wavelength has progressed to g-line (436 nm), i-line (365 nm), KrF excimer laser (248 nm), and ArF excimer laser (193 nm) for ultra-high pressure mercury lamps. In addition, since a small mask blank for manufacturing an LSI mask requires high pattern dimensional accuracy, a thin film is patterned by dry etching.

  On the other hand, a large mask for FPD (flat panel display) is relatively large, for example, 330 mm × 450 mm to 1220 mm × 1400 mm. Therefore, it is often used by being mounted on an exposure apparatus of a mirror projection (equal-size projection exposure by scanning exposure method) method or a lens projection method using a lens. In these exposure apparatuses, multi-color wave exposure using a wide band of ig lines of an ultrahigh pressure mercury lamp is performed with an emphasis on cost and throughput. In addition, in a large mask blank for manufacturing a large mask for FPD, an etching solution (etchant) is emphasized in consideration of cost and throughput rather than emphasizing very high pattern dimensional accuracy comparable to LSI masks. The thin film is patterned by wet etching using ().

  Here, the inventor of the present application considers using a metal silicide-based film formed of a metal silicide-based material as a semi-transparent film or a light-shielding film of a mask blank (FPD mask blank) for manufacturing an FPD device. did. The metal silicide film has good adhesion to the substrate and high chemical resistance. Further, it has good optical characteristics for exposure light in a multicolor wave exposure band as a semi-transparent film or a light-shielding film. However, it has been found that there are the following problems (1) and (2) when used for an FPD mask blank.

(1) The substrate may be damaged by the etching solution for etching the metal silicide film.
As an etching solution for the metal silicide film, for example, an aqueous solution of ammonium hydrogen fluoride or the like is used. In this case, for example, if the substrate is a glass substrate, the substrate surface is damaged, and there is a problem that the surface roughness is rough or the transmittance is lowered. Such a problem has been found to be an obstacle to the future improvement of the quality of large FPD mask blanks and masks.

  In addition, when the substrate is a substrate such as soda lime glass, in addition to this problem, it has been found that there is a problem that white turbidity occurs on the substrate surface and the transmittance further decreases. The reason for this is that the etching solution for metal silicide films (ammonium hydrogen fluoride, etc.) has an etching action on the glass substrate, and when the etching solution contacts the glass substrate surface for a relatively long time, This is thought to be due to the fact that this problem becomes apparent. An aqueous solution of ceric ammonium nitrate and perchloric acid used as an etching solution when patterning a Cr-based material does not have an etching action on the glass substrate. Therefore, such a problem does not occur.

(2) There is a possibility that sufficient pattern dimensional accuracy cannot be obtained.
As described above, in recent years, in the field of LSI masks, a film having the same configuration as a metal silicide film has been developed as a film dedicated to dry etching. Therefore, sufficient studies have not been made on patterning metal silicide films by wet etching. Therefore, for example, even if the films disclosed in Patent Documents 2 and 3 are used as they are for FPD mask blanks, it is difficult to perform patterning with sufficient pattern dimension accuracy by wet etching.

  For example, when the films disclosed in Patent Documents 2 and 3 are used as they are as a semi-transparent film or a light-shielding film of an FPD mask blank and the wet etching with an aqueous solution of ammonium hydrogen fluoride or the like is applied, the cross-sectional shape is poor. Turned out to be. As a result, the pattern dimensional accuracy is reduced as compared with, for example, a patterning of a chromium-based material film. Therefore, when the metal silicide film is patterned by wet etching, there is a possibility that sufficient pattern dimensional accuracy cannot be obtained. Such deterioration of the cross-sectional shape of the pattern and deterioration of the pattern dimension accuracy lead to a decrease in pattern line width uniformity (CD accuracy), and when an FPD device (liquid crystal display device or the like) is manufactured using a large mask. This causes uneven display. For this reason, such a problem may be an obstacle to improving the quality of future large-sized FPD mask blanks and masks.

  Then, an object of this invention is to provide the mask blank and photomask which can solve said subject.

Under the above purpose, the inventors of the present application have conducted intensive research and have arrived at the present invention. The present invention has the following configuration.
(Configuration 1) A mask blank for manufacturing an FPD device, which is a translucent substrate and a translucent substrate that is formed on the substrate and is transparent to light in a wavelength region extending from the i-line to the g-line. A metal silicide film comprising: a light film; and a semi-light-transmitting film or a light-shielding film formed on the light-transmitting film, and a metal silicide-based film formed of a metal silicide-based material including metal and silicon. Is a film patterned by wet etching, and the translucent film is a film of a material having etching selectivity with the metal silicide film. The metal silicide material is, for example, metal silicide or a material obtained by adding an additive element to metal silicide.

  If comprised in this way, a board | substrate can be protected from the etching liquid for wet-etching a metal silicide type | system | group film | membrane. Therefore, it is possible to prevent the substrate from being damaged by the etching solution. Thereby, the above problem (1) can be solved.

  Further, by providing such a light-transmitting film, for example, overetching of the metal silicide film can be appropriately performed without affecting the substrate. Thereby, since the skirting in the cross-sectional shape of the metal silicide film can be reduced, the cross-sectional shape stands up and becomes favorable. Therefore, with this configuration, the pattern dimension accuracy in the wet etching of the metal silicide film can be improved. Thereby, the above problem (2) can be solved. Furthermore, when an FPD device is manufactured using a photomask formed from this mask blank, the occurrence of display unevenness can be suppressed.

  Here, the translucent film is a film having a function as an etching stopper layer, for example. In this case, the translucent film is formed of a material that has etching selectivity with the metal silicide film and is not substantially etched with respect to an etching solution for wet etching the metal silicide film. The translucent film may be a sacrificial layer that is partially etched during wet etching of the metal silicide film. In this case, the translucent film preferably has a thickness that is not completely removed even when the metal silicide film is over-etched. In addition, the translucent film is preferably formed of a material having an etching rate slower than that of the metal silicide film.

  This mask blank is, for example, a gray-tone mask mask blank. This gray tone mask may be a gray tone mask of a type that forms a gray tone portion with a light shielding film, or may be a gray tone mask of a type that forms a gray tone portion with a semi-translucent film.

(Configuration 2) The translucent film is selected from the group consisting of calcium fluoride, magnesium fluoride, tin oxide, indium oxide, indium-tin oxide, tin-antimony oxide, aluminum oxide, hafnium oxide, and lithium fluoride. It is formed of a material containing two or more. These materials have high translucency with respect to light in the wavelength region extending from the i-line to the g-line, and are not substantially etched with an etchant for wet-etching the metal silicide film. Therefore, if comprised in this way, a translucent film | membrane can be formed appropriately. Note that when Al ₂ O ₃ is used as the material of the light-transmitting film, it is preferable to sufficiently oxidize aluminum by heating the light-transmitting film. Thereby, the etching tolerance of a translucent film | membrane can be improved.

  (Configuration 3) The metal silicide-based film is formed of a molybdenum silicide-based material containing molybdenum and silicon. Such a configuration is preferable because it has high chemical resistance (acid resistance) at the time of manufacturing a photomask and less defects during film formation.

  (Configuration 4) The translucent film is a metal nitride film. If comprised in this way, adhesiveness with a board | substrate will be good and a translucent film | membrane can be formed appropriately.

  (Configuration 5) The translucent film is formed of a metal silicide in which at least one of nitrogen and carbon is added as an additive element. As described above, it is preferable to form the same metal silicide material as the semi-transparent film and the light-shielding film because the film is easily formed and the adhesion to the semi-transparent film and the light-shielding film is improved. In this case, not only the semi-transparent film or the light-shielding film but also the translucent film is formed of a silicide-based material. In this case, the light-transmitting film is preferably formed of a silicide-based material whose etching rate is slower than that of the semi-transparent film or the light-shielding film.

  (Configuration 6) The translucent film is a chromium film or a chromium oxide film. If comprised in this way, a translucent film | membrane can be formed appropriately. When the chromium film (Cr film) or the chromium oxide film (CrO film) is thickened, it becomes a light-shielding film against light in a wavelength region extending from the i-line to the g-line. Therefore, it is necessary to sufficiently reduce the thickness of the translucent film so that the necessary transmittance can be obtained.

  (Configuration 7) The translucent film is a diamond-like carbon film. If comprised in this way, a translucent film | membrane can be formed appropriately. Moreover, when comprised in this way, the heat conductivity of a translucent film | membrane can be improved. In a large photomask such as an FPD mask, the effect of uneven temperature distribution on the substrate due to heat generated during exposure is large. However, with this configuration, the temperature distribution in the substrate surface can be made uniform in a photomask manufactured from this mask blank. Thereby, the accuracy of pattern transfer can be increased. Further, this can suppress display unevenness of an FPD device manufactured using this photomask.

  (Configuration 8) A photomask for manufacturing an FPD device, wherein the mask blank according to any one of Configurations 1 to 7 is used and a metal silicide film is patterned by wet etching. If comprised in this way, the effect similar to the structures 1-7 can be acquired.

  In each of the above-described configurations, the mask blank and mask for FPD include mask blanks and masks for manufacturing FPD devices such as LCD (liquid crystal display), plasma display, and organic EL (electroluminescence) display. .

  LCD masks include all masks necessary for LCD production, such as TFT (thin film transistor), especially TFT channel and contact hole, low-temperature polysilicon TFT, color filter, reflector (black matrix), etc. A mask for forming the is included. Other masks for manufacturing display devices include all masks necessary for manufacturing organic EL (electroluminescence) displays, plasma displays, and the like.

  ADVANTAGE OF THE INVENTION According to this invention, the mask blank and photomask which aimed at improvement of both the subject (1) mentioned above and (2) can be provided.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.
FIG. 1 shows a first example of a configuration of a mask blank 10 according to an embodiment of the present invention. The mask blank 10 is a mask blank for manufacturing an FPD device. The mask blank 10 is a large mask blank having a side of 330 mm or more (for example, 330 mm × 450 mm to 1220 mm × 1400 mm), for example.

  The photomask for FPD manufactured from the mask blank 10 is a type of gray tone mask in which a gray tone portion is formed by a light shielding film. For example, a mirror projection (scanning exposure method, equal magnification projection exposure) method or a lens is used. It is mounted and used in the used lens projection type exposure apparatus. This photomask is, for example, a photomask for multi-color wave exposure using light in a wavelength band extending from i-line to g-line, and has, for example, a gray tone pattern of 1 μm or less.

  In this example, the mask blank 10 includes a substrate 12, a translucent film 14, and a light shielding film 16. The mask blank 10 may further include a resist film on the light shielding film 16. Further, an antireflection film may be further provided on the light shielding film 16. As the antireflection film, for example, an oxidized metal silicide film can be used. As the substrate 12, for example, a substrate made of synthetic quartz, soda lime glass, alkali-free glass or the like can be used. A synthetic quartz substrate is particularly preferable from the viewpoints of exposure light for multicolor wave exposure and chemical resistance.

  The translucent film 14 is a translucent film with respect to light in a wavelength region extending from i-line to g-line. The transmissivity of the translucent film 14 is, for example, 80% or more, and more preferably 90% or more, with respect to light in a wavelength region extending from i-line to g-line. The transmittance of the translucent film 14 is preferably higher than the transmittance of the substrate 12. When forming the translucent film | membrane 14 with a material with low transmittance | permeability, it is preferable to form the translucent film | membrane 14 with the film thickness which satisfy | fills this transmittance | permeability.

  The translucent film 14 is, for example, one or two selected from calcium fluoride, magnesium fluoride, tin oxide, indium oxide, indium-tin oxide, tin-antimony oxide, aluminum oxide, hafnium oxide, and lithium fluoride. The material including the above is formed on the substrate 12. In this case, the film thickness of the translucent film 14 is, for example, 20 to 500 angstroms, and more preferably 50 to 350 angstroms. Preferred materials are tin oxide, indium-tin oxide, tin oxide-antimony, hafnium oxide. These materials have good chemical resistance against chemicals used in manufacturing photomasks.

  The translucent film 14 may be a metal nitride film. As the metal nitride film, for example, a SiN film, a TaN film, a CrN film, or the like can be used. In this case, the film thickness of the translucent film 14 is, for example, 20 to 200 Å in the case of a SiN film, and 20 to 50 Å in the case of a TaN film or a CrN film. A SiN film is particularly preferable in that high translucency can be obtained with respect to light in a wavelength region extending from the i-line to the g-line.

  The translucent film 14 may be formed of a metal silicide in which at least one of nitrogen and carbon is added as an additive element. In this case, the film thickness of the translucent film 14 is, for example, 20 to 100 angstroms, and more preferably 20 to 50 angstroms. As the translucent film 14, for example, a MoSiN film, a MoSiC film, a MoSiON film, a MoSiCO film, a MoSiCON film, or the like can be used. It is also conceivable to use a film in which molybdenum (Mo) in each of the above films is replaced with tantalum (Ta), titanium (Ti), tungsten (W), or the like.

  The translucent film 14 may be a thinned chromium film (Cr film) or a chromium oxide film (CrO film). In this case, the film thickness of the translucent film 14 is, for example, 20 to 50 Å in the case of a chromium film, and 20 to 100 Å in the case of a chromium oxide film.

  The translucent film 14 may be a diamond-like carbon film. In this case, the film thickness of the translucent film 14 is, for example, 20 to 50 angstroms. Moreover, the translucent film | membrane 14 is formed by CVD method, for example. The translucent film 14 may be formed by a sputtering method.

  The light shielding film 16 is a metal silicide film formed of a metal silicide material containing a metal and silicon, and is formed on the translucent film 14. The light shielding film 16 is formed to have a film thickness with an optical density of 3 or more. The thickness of the light shielding film 16 is, for example, 850 to 1800 angstroms.

Examples of the light shielding film 16 that is a metal silicide film include molybdenum silicide (MoSi), tantalum silicide (TaSi), titanium silicide (TiSi), tungsten silicide (WSi), oxides thereof (MoSiO, etc.), and nitrides. (MoSiN or the like) or an oxynitride (MoSiON or the like) film or the like can be used. Further, a stacked film of these films may be used. In addition, the ratio of a metal and silicon can be changed suitably. For example, molybdenum silicide-based metal silicide films include MoSi films (Mo: Si = 50: 50 (atomic% ratio)), MoSi ₂ films (Mo: Si = 33: 67 (atomic% ratio)), MoSi ₄ A film (Mo: Si = 20: 80 (atomic% ratio)) or the like can be used.

  The light shielding film 16 is a film that is patterned by wet etching. At least a part of the light shielding film 16 is a part to be a gray tone part in the gray tone mask, and is patterned into a gray tone pattern having a fine light shielding pattern and a fine transmission part below the resolution limit of the exposure apparatus for large FPD. . Examples of the etchant used for wet etching of the light shielding film 16 include fluorine compounds such as ammonium hydrogen fluoride, ammonium fluoride, silicohydrofluoric acid, boron fluoride acid, hydrofluoric acid, hydrogen peroxide, nitric acid, and the like. An aqueous solution in which an oxidizing agent such as sulfuric acid is mixed can be used.

  Here, in the present example, the translucent film 14 has resistance to an etching solution for wet etching of the light shielding film 16. Therefore, the translucent film 14 remains on the substrate 12 without being removed by wet etching of the light shielding film 16. As a result, the substrate 12 can be appropriately protected from the etchant for wet etching of the light shielding film 16. Further, it is possible to prevent the substrate 12 from being damaged by this etching solution.

  Furthermore, by providing the translucent film 14, the light shielding film 16 can be overetched appropriately without affecting the substrate 12. Therefore, according to this example, the pattern dimension accuracy in the wet etching of the light shielding film 16 can be improved. Moreover, when an FPD device is produced using the photomask produced from the mask blank 10 by this, generation | occurrence | production of display nonuniformity can be suppressed.

  FIG. 2 shows a second example of the configuration of the mask blank 10. In this example, the photomask for FPD manufactured from the mask blank 10 is a type of gray tone mask in which a gray tone portion is formed with a semi-transparent film. The mask blank 10 is an underlay type (advanced type) mask blank, and includes a substrate 12, a light transmissive film 14, a semi-light transmissive film 18, and a light shielding film 20. The mask blank 10 may further include a resist film on the light shielding film 20. Except for the points described below, the configuration denoted by the same reference numerals in FIG. 2 as in FIG. 1 is the same as or similar to the configuration in FIG.

  The translucent film 18 is the same or similar metal silicide film as the light shielding film 16 described with reference to FIG. The semi-transparent film 18 is formed on the substrate 12 and the translucent film 14 prior to the light shielding film 16 and below the light shielding film 16. The transmissivity of the semi-transmissive film 18 is, for example, 10 to 60%. The film thickness of the translucent film 18 is, for example, 20 to 100 angstroms, and more preferably 40 to 60 angstroms.

  The light shielding film 20 is a light shielding film formed of a chromium-based material. The light shielding film 20 may be a film obtained by adding one or more additive elements selected from oxygen, nitrogen, and carbon to chromium (Cr), or a laminated film thereof. For example, the light shielding film 20 is a laminated film in which chromium nitride (CrN), chromium carbide (CrC), and chromium oxynitride (CrON) are laminated in this order from the substrate 12 side.

  The semi-transparent film 18 and the light shielding film 20 are patterned by wet etching using different etching solutions. As an etchant for wet etching of the light shielding film 20, for example, various known etchants for etching a chromium-based film can be used. As the etchant for wet etching of the semi-transparent film 18, the same or similar etchant as the etchant used for wet etching of the light shielding film 16 described with reference to FIG. 1 can be used. The semi-transparent film 18 is patterned by wet etching to form a gray tone portion in the gray tone mask.

  Also in this example, the translucent film 14 is resistant to an etching solution for wet etching of the semi-transparent film 18. Therefore, the translucent film 14 remains on the substrate 12 without being removed by wet etching of the semi-transparent film 18. Thereby, the substrate 12 can be appropriately protected from the etching solution for wet etching of the semi-transparent film 18. Further, it is possible to prevent the substrate 12 from being damaged by this etching solution.

  Furthermore, by providing the translucent film 14, the semi-transparent film 18 can be appropriately over-etched without affecting the substrate 12. Therefore, according to this example, the pattern dimension accuracy in the wet etching of the semi-transparent film 18 can be improved. In addition, when an FPD device is manufactured using a photomask formed from the mask blank 10, the occurrence of display unevenness can be suppressed.

Hereinafter, the present invention will be described in more detail based on examples.
Example 1
On a large glass substrate (synthetic quartz (QZ) 10 mm thickness, size 850 mm × 1200 mm), a light transmitting film, a light shielding film, and an antireflection film were formed using a large in-line sputtering apparatus. Films are formed in each space (sputter chamber) continuously arranged in a large in-line sputtering apparatus, with a hafnium oxide (HfO ₂ ) target and a molybdenum silicide (MoSi ₂ ) target (Mo: 33 mol%, Si: 67). First, in the first sputtering chamber, a transparent film of HfO ₂ film was formed to 100 Å using Ar gas as a sputtering gas with respect to the hafnium oxide target. Next, in the next sputtering chamber, a light shielding film of MoSi ₂ film was formed to 1000 Å on the MoSi ₂ target using Ar gas as a sputtering gas. Further, an anti-reflection film of MoSi ₂ O film was formed to 400 Å using Ar gas and O ₂ gas as sputtering gas, and a large mask blank for FPD was produced.

  Using the mask blank prepared above, after a cleaning process (pure water, room temperature), a resist solution is applied using a known slit coater (slit coater described in JP-A-2005-286232), and developed. A resist pattern is formed. Using this resist pattern as a mask, an anti-reflective film and a light-shielding film are patterned by wet etching using an aqueous solution obtained by mixing ammonium hydrogen fluoride and hydrogen peroxide as an etching solution. A mask was prepared. This photomask has a normal pattern with a width of 5 μm and a gray tone pattern with a width of 1 μm.

  When this large-sized mask for FPD was observed with a scanning electron microscope (SEM), the cross-sectional shape was good and the pattern dimensional accuracy was good for any of the mask patterns. Further, when an FPD device was produced using this large FPD mask and display unevenness was confirmed, it was confirmed that the produced FPD device had no display unevenness.

  Furthermore, this large-sized mask for FPD was observed with a scanning electron microscope (SEM) and the transmittance was measured. There was no damage to the substrate surface or rough surface roughness that was thought to be based on the etching action of the substrate surface by the etching solution, and no reduction in transmittance was confirmed.

  Furthermore, the state of the substrate surface was confirmed in the same manner as in Example 1 except that the substrate was replaced with soda lime glass. There was no damage to the substrate surface, rough surface roughness, or white turbidity on the substrate surface, which seemed to be based on the etching action of the glass substrate surface by the etching solution, and no decrease in transmittance was confirmed.

(Comparative Example 1)
A large-sized mask for FPD according to Comparative Example 1 was produced in the same manner as in Example 1 except that the translucent film of the HfO ₂ film was not formed. When this large FPD mask was observed with a scanning electron microscope (SEM), the mask pattern was skirted and the cross-sectional shape was deteriorated. Therefore, the pattern dimensional accuracy by wet etching was insufficient.

  In addition, an FPD device was fabricated using this FPD large mask. In this FPD device, it was confirmed that display unevenness caused by poor pattern cross-sectional shape and pattern dimensional accuracy occurred. Further, display unevenness occurred particularly in a region corresponding to a gray tone pattern having a width of 1 μm.

  Furthermore, this large-sized mask for FPD was observed with a scanning electron microscope (SEM) and the transmittance was measured. Damage to the glass substrate surface, which appears to be based on the etching action of the glass substrate surface by the etching solution, and rough surface roughness were confirmed, and a decrease in transmittance was also confirmed.

  Furthermore, the state of the substrate surface was confirmed in the same manner as in Example 1 except that the substrate was replaced with soda lime glass. It was confirmed that the glass substrate surface was damaged due to the etching action of the substrate surface by the etching solution, the surface roughness was rough, the white turbidity of the glass substrate surface was generated, and the transmittance was also lowered.

(Example 2)
On a large glass substrate (synthetic quartz (QZ) 10 mm thickness, size 850 mm × 1200 mm), a light transmitting film, a semi-light transmitting film, and a light shielding film were formed using a large in-line sputtering apparatus. Film formation is performed in each space (sputter chamber) continuously arranged in a large in-line sputtering apparatus, a hafnium oxide (HfO ₂ ) target, a MoSi ₂ target (Mo: 33 mol%, Si: 67 mol%), and Each Cr target was arranged, and first, in the first sputtering chamber, a transparent film of HfO ₂ film was formed to 100 Å using Ar gas as a sputtering gas with respect to the hafnium oxide target. Next, in the next sputtering chamber, a semi-transparent film of MoSi ₂ film was formed to a thickness of 45 Å using Ar gas as a sputtering gas with respect to the MoSi ₂ target.

Next, a light shielding film was formed using a Cr target. First, CrN film is 150 Å using Ar gas and N ₂ gas as sputtering gas, then CrC film is 620 Å using Ar gas and CH ₄ gas as sputtering gas, then CrON film is 250 Å using Ar gas and NO gas as sputtering gas Then, a large film blank for FPD (gray tone mask blank) was prepared by continuous film formation.

  Using the mask blank produced above, the light-shielding film was patterned by a known method after cleaning treatment (pure water, room temperature). Next, in the same manner as the patterning of the light shielding film of Example 1, the semi-transparent film was patterned to produce a large gray tone mask for FPD. The patterned semi-transparent film has a normal pattern with a width of 5 μm.

  When this large-sized mask for FPD was observed with a scanning electron microscope (SEM), the cross-sectional shape was good and the pattern dimensional accuracy was good for any of the mask patterns. Further, when an FPD device was manufactured using this large gray-tone mask for FPD and display unevenness was confirmed, it was confirmed that there was no display unevenness in the manufactured FPD device. Further, the state of the substrate was also good as in Example 1. The same applies when the substrate is replaced with soda lime glass.

(Examples 3 to 7)
In Example 1 described above, as the light-transmitting film, a tin oxide-antimony (Sn _x Sb _y O _z ) film (thickness 150 Å) (Example 3), a silicon nitride (SiN) film (thickness 170 Å) (Example 4), nitrided molybdenum silicide (MoSiN) film (film thickness 45 angstroms) (example 5), chromium oxide (CrO) film (film thickness 80 angstroms) (example 6), diamond-like carbon ( A large-size mask blank for FPD and a large-size mask for FPD were produced in the same manner as in Example 1 except that a diamond-like carbon film (film thickness 20 Å) (Example 7) was used.

  When this large-sized mask for FPD was observed with a scanning electron microscope (SEM), the cross-sectional shape was good and the pattern dimensional accuracy was good for any of the mask patterns. Further, when an FPD device was produced using this large FPD mask and display unevenness was confirmed, it was confirmed that the produced FPD device had no display unevenness.

  Furthermore, this large-sized mask for FPD was observed with a scanning electron microscope (SEM) and the transmittance was measured. There was no damage to the substrate surface or rough surface roughness that was thought to be based on the etching action of the substrate surface by the etching solution, and no reduction in transmittance was confirmed. The same result was obtained when the substrate was replaced with soda lime glass.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the description of the scope of claims that embodiments with such changes or improvements can be included in the technical scope of the present invention.

  The present invention can be suitably applied to, for example, a mask blank and a mask for manufacturing an FPD device.

It is a figure which shows the 1st example of a structure of the mask blank 10 which concerns on one Embodiment of this invention. It is a figure which shows the 2nd example of a structure of the mask blank.

DESCRIPTION OF SYMBOLS 10 ... Mask blank, 12 ... Substrate, 14 ... Translucent film, 16 ... Light shielding film (metal silicide film), 18 ... Semi-transparent film (metal silicide film), 20 ... Light-shielding film

Claims (12)

A mask blank for manufacturing an FPD device,
A glass substrate;
A translucent film that is formed in contact with the glass substrate and is translucent to light in a wavelength region extending from i-line to g-line;
A semi-transparent film or a light-shielding film formed in contact with the translucent film, and a metal silicide-based film formed of a metal silicide-based material containing metal and silicon,
The metal silicide film is a film that is patterned by wet etching using an etchant that is an aqueous solution in which one or more fluorine compounds selected from ammonium hydrogen fluoride, ammonium fluoride, and fluorinated boronic acid and an oxidizing agent are mixed. And
2. The mask blank according to claim 1, wherein the translucent film is a film formed of a material having etching selectivity with respect to the etchant used when wet etching the metal silicide film.   The mask blank according to claim 1, wherein the translucent film has a thickness of 20 to 500 angstroms.   The translucent film includes one or more selected from calcium fluoride, magnesium fluoride, tin oxide, indium oxide, indium oxide-tin, tin oxide-antimony, aluminum oxide, hafnium oxide, and lithium fluoride. The mask blank according to claim 1, wherein the mask blank is made of a material containing the mask blank.   The translucent film is formed of a material containing one or more selected from calcium fluoride, magnesium fluoride, tin oxide-antimony, aluminum oxide, hafnium oxide, and lithium fluoride. The mask blank according to claim 1.   The mask blank according to claim 1, wherein the metal silicide film is made of a molybdenum silicide material containing molybdenum and silicon.   The mask blank according to claim 1, wherein the translucent film is a chromium film or a chromium oxide film.   The mask blank according to claim 1, wherein the glass substrate is made of synthetic quartz.   8. The metal silicide film according to claim 1, wherein the metal silicide film is a semi-transparent film, and includes a light-shielding film formed of a material containing chromium on the metal silicide film. 9. Mask blank.   A photomask for manufacturing an FPD device, wherein the mask blank according to any one of claims 1 to 7 is used and the metal silicide film is patterned by wet etching.   A photomask for manufacturing an FPD device, wherein the mask blank according to claim 8 is used to pattern the light shielding film and the metal silicide film by wet etching. A photomask for manufacturing an FPD device,
A glass substrate;
A translucent film formed in contact with the glass substrate and translucent to light in a wavelength region extending from i-line to g-line;
A light-shielding film formed in contact with the light-transmitting film, made of a metal silicide-based material containing metal and silicon, and patterned by wet etching using an etchant;
The translucent film is formed of a material having etching selectivity with respect to an etchant used for wet etching of the light shielding film, and remains in a region on the glass substrate where the light shielding film is removed by patterning. And
The photomask according to claim 1, wherein the etching solution is an aqueous solution in which one or more fluorine compounds selected from ammonium hydrogen fluoride, ammonium fluoride, and boron fluoric acid are mixed with an oxidizing agent. A photomask for manufacturing an FPD device,
A glass substrate;
A translucent film formed in contact with the glass substrate and translucent to light in a wavelength region extending from i-line to g-line;
A semi-transparent film formed in contact with the translucent film, made of a metal silicide-based material containing metal and silicon, and patterned by wet etching using an etchant;
A light-shielding film formed on the semi-transparent film, made of a material containing chromium, and patterned;
The translucent film is formed of a material having etching selectivity with respect to an etchant used for wet etching of the semi-translucent film, and is formed in a region on the glass substrate where the semi-transparent film is removed by patterning. Also remains,
The photomask according to claim 1, wherein the etching solution is an aqueous solution in which one or more fluorine compounds selected from ammonium hydrogen fluoride, ammonium fluoride, and boron fluoric acid are mixed with an oxidizing agent.

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