KR100961570B1 - Mask blank and photomask - Google Patents

Abstract

A mask blank for producing an FPD device having at least one of a semi-translucent film and a light-shielding film on a light-transmissive substrate, wherein the semi-translucent film or the light-shielding film contains a metal and silicon. The semi-translucent film made of the metal silicide-based material and made of the metal silicide-based material, or the light-shielding film made of the metal silicide-based material, is subjected to wet etching in the depth direction of the film of the semi-translucent film or the light-shielding film. It is characterized by the fact that the film is configured to have a high etching rate.

Light Transmissive Substrate, Translucent Film, Light Blocking Film, FPD Device, Mask Blank

Description

Mask blanks and photomasks {MASK BLANK AND PHOTOMASK}

BRIEF DESCRIPTION OF THE DRAWINGS It is typical sectional drawing for demonstrating the mask pattern obtained by wet-etching the MoSi type film which has a predetermined | prescribed film structure of this invention.

FIG. 2 is a schematic cross-sectional view for explaining a mask pattern obtained by wet etching a MoSi-based film developed as a film dedicated to dry etching. FIG.

FIG. 3 is a schematic cross-sectional view for explaining a mask pattern obtained by wet etching a MoSi-based film having a film structure which merely accelerates the wet etching rate of the layer immediately adjacent to the substrate.

4 is a view for explaining an aspect of a large-sized mask for FPD.

5 is a diagram for explaining another embodiment of the large-sized mask for FPD.

Fig. 6 is a view for explaining a gray tone mask having a semi-transmissive film, in which Fig. 6 (1) is a partial plan view and Fig. 6 (2) is a partial sectional view.

FIG. 7 is a view for explaining a gray tone mask having a fine light shielding pattern below a resolution limit, in which FIG. 7 (1) is a partial plan view, and FIG. 7 (2) is a partial sectional view.

<Explanation of symbols for the main parts of the drawings>

10: translucent substrate

11: semipermeable membrane

12: light transmitting film

22: upper floor

[Non-Patent Document 1] Monthly FPD Intelligence, p.31-35, May 1999

[Patent Document 1] Japanese Patent Application Laid-Open No. 3-66656

[Patent Document 2] Japanese Patent Application Laid-Open No. 4-35743

[Patent Document 3] Japanese Patent Application Laid-Open No. 62-218585

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to mask blanks and photomasks, and more particularly to mask blanks for manufacturing FPD devices, photomasks fabricated using such mask blanks, and the like.

In recent years, in the field of masks for large-scale FPDs, attempts have been made to reduce the number of masks by using a gray tone mask having a semi-transmissive region (so-called gray tone portion) (Non-Patent Document 1).

Here, as shown in Figs. 6 (1) and 7 (1), the gray tone mask includes a light blocking portion 1, a transmitting portion 2, and a gray tone portion (a semi-transmissive region) on a transparent substrate. Have 3). The gray tone part 3 has a function of adjusting the transmission amount, for example, a region in which a semi-transmissive film (half transmissive film) 3a 'for a gray tone mask is formed, as shown in Fig. 6 (1), Alternatively, as shown in Fig. 7 (1), it is a region in which a gray tone pattern (fine light shielding pattern 3a and fine transmitting portion 3b below the resolution limit of a large FPD exposure machine using a gray tone mask) is formed, It is formed for the purpose of reducing the amount of light transmitted through these areas and reducing the amount of irradiation by this area to control the reduced film thickness after development of the photoresist corresponding to this area to a desired value.

When a large-scale gray tone mask is mounted on a large-scale exposure apparatus of a mirror projection method or a lens projection method using a lens, the exposure light passing through the gray tone part 3 becomes insufficient in overall exposure amount. The positive photoresist exposed through 3) only becomes thin and remains on the substrate. That is, since the difference in the solubility with respect to a developing solution arises in the part corresponding to the normal light-shielding part 1 and the part corresponding to the gray tone part 3 by a difference in an exposure amount, the resist shape after image development is shown in FIG. 2) and part 2 'corresponding to the normal light shielding part 1, for example, about 1 micrometer and the part 3 corresponding to the gray tone part 3 as shown to (2) of FIG. ') Is, for example, about 0.4 to 0.5 mu m, and the part corresponding to the permeation part 2 becomes the part 2' without a resist. Then, a first etching of the substrate to be processed is performed in the resistless portion 2 ', and the resist of the thin portion 3' corresponding to the gray tone portion 3 is removed by ashing or the like, and the second etching is performed in this portion. By performing a process of two conventional masks with one mask, the number of masks is reduced.

By the way, LSI masks for manufacturing semiconductor devices such as microprocessors, semiconductor memories, and system LSIs are relatively small, up to about 6 by 6 inches, and are mounted in a reduced projection exposure apparatus by a stepper (shot step exposure) method. Often used. In such a mask for LSI, shortening of the exposure wavelength is aimed at breaking the resolution limit determined by the exposure wavelength. Here, in the LSI mask, monochromatic exposure light is used from the viewpoint of eliminating chromatic aberration by the lens system and thereby improving resolution. The shortening of the monochromatic exposure wavelength with respect to this LSI mask proceeds with g line (436 nm), i line (365 nm), KrF excimer laser (248 nm), ArF excimer laser (193 nm) of an ultra-high pressure mercury lamp. have.

Moreover, in the small mask blank for manufacturing the mask for LSI, since high etching precision is needed, patterning of the thin film formed on the mask blank by dry etching is performed.

Initially, in the LSI mask, as a light-shielding film material which can be patterned by dry etching, for example, a film composed of Mo and Si (hereinafter referred to as MoSi film) has been proposed (Patent Document 1). In the LSI mask, as a light-shielding film material having an antireflection function that can be patterned by dry etching, for example, a film composed of a substrate / MoSi film / Mo, and Si and O (hereinafter referred to as MoSi0 film) is It was proposed (Patent Document 2). As described above, in the LSI mask, a film made of a material containing Mo and Si (hereinafter referred to as MoSi-based material) (hereinafter referred to as MoSi-based film) has been developed as a film dedicated to dry etching, whereas MoSi There is also a proposal for patterning a light-shielding film made of a system material by wet etching (Patent Document 3).

With respect to the mask for LSI described above, the large size mask for FPD (flat panel display) is relatively large from 330 mm x 450 mm to 1220 mm x 1400 mm, and it is a mirror projection (equivalent projection exposure by scanning exposure method) method or a lens. It is often mounted on and used in an exposure apparatus of a lens projection method using the same. Moreover, polychromatic wave exposure is performed using the wide band of i-g line | wires, such as an ultrahigh pressure mercury lamp.

In addition, in the large-sized mask blank for manufacturing the large-sized mask for FPD, the mask blank is made by wet etching using the etching liquid with an emphasis on the cost surface and throughput, rather than the very high etching precision of the same level as the LSI mask. Patterning of the thin film formed on it is performed.

Here, as a large-sized mask blank for FPD and a mask, as shown in FIG. 4, the translucent film 12 is formed on the translucent board | substrate 10, this is patterned by wet etching, and a light shielding film is performed. In a large-sized mask blank for FPD and a mask (hereinafter, referred to as a light shielding film type) of the type for forming the pattern 12, a Cr-based material is optimally considered as a light shielding material and is currently used.

In addition, as the large-sized mask blank and mask for FPD, as shown in FIG. 5 (1), the translucent film 11 for light shielding and the light-shielding film 12 for a gray tone mask are carried out on the translucent board | substrate 10 in this order. And a semi-transmissive film formed by wet etching of these films to form a semi-transmissive film pattern for a gray tone mask and a light-shielding film pattern (pre-mounted) type (the semi-transmissive film is below the light-shielding film). Greytone mask blanks and masks of the type (formed first at) are proposed. In this underlaying type gray tone mask blank and mask, MoSi-based materials are optimally considered as semi-transmissive films and Cr-based materials are used at present. In this case, as the wet etching solution of the MoSi-based material, the inventors of the present invention apply the "aqueous solution of ammonium hydrogen fluoride and hydrogen peroxide" proposed in Patent Document 1. In addition, in this laying type gray tone mask blank and mask, the film (for example, MoSiO film, MoSiON film, etc.) currently developed and used as a halftone phase shifter material in LSI conventionally as a MoSi material is CT. Since the etching selectivity with respect to the etchant of a system material is high, it is excellent also in acid resistance, and is considered optimal, it is used as it is.

However, it was found that the following problems exist in the large mask blank and mask for FPD.

(1) As described above, in recent years, MoSi-based materials have been developed as a film dedicated to dry etching, and a MoSi based film developed as a film dedicated to such dry etching, for example, a substrate described in Patent Document 1 / MoSi film or the substrate / MoSi film / MoSi0 film described in Patent Document 2) or a film (for example, a MoSiO film or a MoSiON film) developed as the above-described half-tone phase shifter film dedicated to dry etching, as it is, a large mask blank. When wet etching with an aqueous solution (such as ammonium hydrogen fluoride) is used as a material of a semi-transmissive film or a light-shielding film of the film, damage occurs on the surface of the glass substrate, and the surface roughness becomes rough or the transmittance decreases. There has been a problem, and it has been found that this problem will be a problem in the future of the large mask blank for FPD and the high quality of the mask. In addition, in the case of a glass substrate such as soda lime glass, in addition to the problem that damage occurs on the surface of the glass substrate, the surface roughness is rough or transmittance is lowered, furthermore, there is a problem in that the glass substrate surface has a turbidity and the transmittance is further lowered. I knew there was. These reasons are that aqueous solutions such as ammonium hydrogen fluoride (etchants) used when patterning MoSi-based materials have an etching action with respect to the glass substrate. Therefore, these problems occur when the etchant contacts the glass substrate surface for a relatively long time. Is considered to be present. Incidentally, since the aqueous solution of dicerium ammonium acetate and perchloric acid (etchant) used when patterning the Cr-based material does not have an etching effect on the glass substrate, such a problem does not occur.

(2) MoSi-based films developed as the films for dry etching as described above, for example, the substrate / MoSi film described in Patent Document 1 and the substrate / MoSi film / MoSi0 Film described in Patent Document 2); A film (e.g., a MoSiO film and a MoSiON film) developed as the half-tone phase shifter film dedicated to dry etching described above is used as it is as a material of a semi-transmissive film or a light-shielding film of a large-sized mask blank. When wet etching with an aqueous solution (etchant) was applied, it was found that the cross-sectional shape was bad, and the pattern accuracy due to wet etching had a problem inferior to Cr-based materials. Such deterioration of the pattern cross-sectional shape and deterioration of the pattern accuracy cause display unevenness when the FPD device (liquid crystal display device) is manufactured using a large-sized mask. Therefore, in order to improve the quality of the large-sized mask blank for FPD and the mask in the future, it is necessary to improve the semi-translucent film made of MoSi-based material in the laying-down type gray tone mask blank and mask. In addition, in the light-shielding film type gray tone mask blank and mask, it is difficult to replace the material of the light-shielding film with the Cr-based material from the MoSi-based material.

In detail, as shown in Fig. 2, in the case of the film 30 developed as the above-described film for exclusive use of dry etching, the edges are formed in any case and the cross-sectional shape is bad. The cross-sectional shape is the same even if overetched as shown by the dotted line of FIG. In addition, in the case of Cr, when overetching by wet etching, the edge becomes small and a cross-sectional shape stands. This tendency is remarkable for Cr having a high etching rate.

An object of the present invention is to provide a large-sized mask blank for FPD and a large-sized photomask for FPD in which the problems of (1) and (2) of the present invention are improved.

Under the above object, the present inventors earnestly researched and developed the large mask blank for FPD and the large photomask for FPD.

As a result, when wet-etching a semi-translucent film or light-shielding film made of a MoSi-based material formed directly on a light-transmissive substrate with an aqueous solution (such as an etchant) such as ammonium hydrogen fluoride, in the semi-translucent film or light-shielding film, i) the cross-sectional shape of the pattern right next to the substrate is a layer where the cross-sectional shape is well etched without edges, and (ii) the etching time near the substrate is relatively short relative to the top layer (at the same time as the material directly next to the conventional substrate). A layer having a film structure in which the wet etching rate is increased in the depth direction of the film so as to be suitable for realizing the characteristics of both (i) and (ii), by forming a layer capable of being directly next to the substrate. By setting it as a light-transmissive film or a light-shielding film, it is borne in mind that improvement of the subject (1) and (2) of this invention can be aimed at, and reached this invention. .

In detail, by setting it as the film structure of the said invention, the cross-sectional shape of a pattern will become favorable like FIG. 1 (the cross section of a pattern will become easy to stand perpendicular to the surface of the board | substrate 10). For this reason, as shown in Fig. 1, for example, the main portion (upper layer 22) of the film from the surface side of the film to the layer 21 immediately adjacent to the substrate is made of MoSi film or the like, and the cross-sectional shape is good. In addition to utilizing the wet etching characteristics, the wet etching rate to the side of the substrate is slowed to uniformly wet etch in the plane of the large area. The layer 21 to be etched &quot; is formed right next to the substrate (the layer 21 is formed next to the substrate with a predetermined thickness with a high wet etching rate in a predetermined range relative to the upper layer 22), as shown in FIG. It becomes a cross-sectional shape as a whole pattern, and pattern precision is inferior to a Cr type material. Thereby, when a FPD device (liquid crystal display device) is manufactured using a large mask, generation | occurrence | production of a display nonuniformity can be avoided. That is, the subject of said (2) can be eliminated.

In addition, by forming the layer 21 directly adjacent to the substrate (2) which allows the etching time at the immediate side of the substrate to be relatively short with respect to the upper layer 22 (at the same time with respect to the material immediately adjacent to the conventional substrate), Since the etching time in the immediate vicinity of a board | substrate can be shortened compared with the past, and since the cross-sectional shape is favorable as mentioned above, the over-etching time can also be shortened, and the time which the surface of a board | substrate is exposed to etching liquid can be shortened. Thereby, the subject of said (1) can be eliminated.

In addition, since the film of the structure is a MoSi film or the like as its main part, the optical density or semi-transmittance required as a light-shielding film or a semi-transmissive film can be realized with a somewhat thin film thickness. Moreover, the film | membrane of the said structure has high chemical-resistance of the outermost layer of a film | membrane, and therefore there is little change of the optical characteristic by washing | cleaning etc.

In addition, if the wet etching rate of the layer 21 immediately adjacent to the substrate is simply increased, if the wet etching rate is too fast, the cross-sectional shape will not be good as shown in FIG. 3. In the case where the thickness of the layer 21 immediately adjacent to the substrate (the layer 21 whose wet etching rate is relatively fast relative to the upper layer 22) is too thick, the cross-sectional shape is not good as well.

As described above, in the case of a film having a structure in which the wet etching rate is slowed in the depth direction of the film (for example, the substrate / MoSi film / MoSiO film described in Patent Document 2), (1) of the present invention Cannot solve the problem of (2) (refer FIG. 2).

In addition, when wet-etching the translucent film or the light-shielding film which consists of MoSi type material formed directly on the translucent board | substrate by aqueous solution (such as an ammonium hydrogen fluoride), these semi-translucent film or light-shielding film is Mo and Si In the case of a single layer of a film composed of and O (hereinafter referred to as a MoSi0 film), the entire etching rate is high. However, as shown in Fig. 2, the edges are formed and the cross-sectional shape is not bad. The problem of (2) of the present invention cannot be solved. In addition, in this way, the etching rate of the entire film is simply increased, and the time that the surface of the substrate is exposed to the etching solution is shortened by the same amount (as much as the etching rate of the material immediately adjacent to the substrate). In consideration of the edges, overetching for dimensional accuracy adjustment is necessary, and therefore, the problem (1) of the present invention cannot be solved. In addition, in the case of a single layer of MoSi0, in order to obtain the optical properties (transmittance, optical density, etc.) required as a semi-transmissive film or a light-shielding film, it is necessary to increase the thickness of the film, and the etching time also increases with the substrate surface. The time exposed to this etching liquid becomes long.

This invention has the following structures.

(Configuration 1)

As a mask blank for manufacturing an FPD device which has at least one of the translucent film | membrane which has a function which adjusts the transmittance | permeability, and a light-shielding film | membrane on a translucent board | substrate,

The semi-transmissive film or the light-shielding film is made of a metal silicide-based material containing a metal and silicon,

In addition, the semi-translucent film | membrane which consists of said metal silicide system materials, or the light-shielding film | membrane which consists of said metal silicide system materials,

A mask blank for manufacturing an FPD device, characterized in that the film is configured to increase the etching rate by wet etching in the depth direction of the semi-transmissive film or the film of the light-shielding film.

(Composition 2)

The semi-transmissive film or the light-shielding film is composed of a metal silicide-based material having a relatively high etching rate by wet etching, and the upper side thereof has a relatively high etching rate by wet etching compared to the material on the substrate side. A mask blank for producing the FPD device according to Configuration 1, which is a film composed of a slow metal silicide-based material.

(Composition 3)

The mask blank for manufacturing the FPD device according to Configuration 2, wherein the material on the substrate side in the semi-transmissive film or the light-shielding film is a material containing a large amount of oxygen as compared to the material on the upper side. .

(Composition 4)

The semi-transmissive film or the light-shielding film is selected from aluminum, titanium, silver, phosphorus, tungsten, tantalum, boron, gallium, and indium, which are additive elements that accelerate the etching rate by wet etching to a material composed of molybdenum and silicon. Molybdenum silicide-based material comprising molybdenum and silicon having a substrate side composed of a material to which one or more additional elements are added, and an upper side thereof having a relatively slow etching rate by wet etching compared to the material on the substrate side. It is a film | membrane comprised with the mask blank for manufacturing the FPD device of the structure 2 characterized by the above-mentioned.

(Configuration 5)

The semi-transmissive film or the light-shielding film is an etching rate by wet etching by changing the content ratio of the metal and silicon composed of a material containing a metal and silicon toward the depth direction of the film of the translucent film or the light-shielding film. Is the membrane that controlled

The board | substrate side is comprised from the material containing the metal and silicon which made content of metal more than 30 atomic%,

The mask blank for manufacturing the FPD device of the structure 2 characterized by the above structure being a film | membrane comprised from the material containing the metal and silicon which increased the content of silicon to 80 atomic% or more.

(Configuration 6)

The mask blank for manufacturing the FPD device according to any one of Configurations 1 to 5, wherein the composition in the semi-transmissive film or the light-shielding film is changed stepwise or continuously toward the depth direction of the film.

(Configuration 7)

A photomask for producing an FPD device, wherein the semi-transmissive film or the light-shielding film is patterned by wet etching using the mask blank according to any one of Configurations 1 to 6.

According to this invention, the large sized mask blank for FPD and the large sized photomask for FPD which aimed at the improvement of both the above-mentioned objects (1) and (2) of this invention can be provided.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

As described above, in the present invention, when the semi-transmissive film or the light-shielding film made of the metal silicide-based material formed on the light-transmissive substrate is wet-etched with an aqueous solution (such as an etchant) such as ammonium hydrogen fluoride, these semi-translucent films or In the light-shielding film, (i) the cross-sectional shape of the pattern is immediately etched without end edges in the immediate vicinity of the substrate, and (ii) the etching time in the immediate vicinity of the substrate is applied to the upper layer (at the same time as the conventional substrate By forming a layer which can be made relatively short with respect to the material, directly adjacent to the substrate, both the above-described problems (1) and (2) of the present invention can be improved.

In other words, a semi-transmissive film or light-shielding film having a film structure in which the wet etching rate is increased in the depth direction of the film so as to be suitable for realizing both the above-mentioned characteristics (i) and (ii) (constitution 1) ), The improvement of both the above-mentioned subjects (1) and (2) of this invention is aimed at.

In other words, the semi-transmissive film or the light-shielding film has a relative etching rate of wet etching on the substrate side (near the substrate) so as to be suitable for realizing both of the characteristics (i) and (ii). In this case, the upper side is formed of a material having a relatively slow etching rate due to wet etching compared to the material on the substrate side (constitution 2). Improvement of both is aimed at.

In the present invention, the thickness of each layer in the semi-translucent film or the light-shielding film having the film structure of the present invention is predetermined so as to be suitable for realizing both of the characteristics (i) and (ii). It is necessary to adjust the range (Requirement 1). Specifically, it can be represented by the ratio of the area | region which consists of a material with the etching rate by the wet etching of the board | substrate side (right side of the board | substrate) which occupies the thickness of the whole translucent film or light-shielding film. For example, in the translucent film, the ratio is preferably 0.2 to 0.5, and in the light-shielding film, the ratio is preferably 0.05 to 0.3.

In addition, as a semi-transmissive film, in addition to the said requirement 1, the film thickness of each layer and the composition of each layer are adjusted so that the transmittance | permeability in the range over i line | wire may be 10 to 60%, for example. There is a need.

Moreover, as a light-shielding film, in addition to said requirement 1, it is necessary to adjust the film thickness of each layer and the composition of each layer so that the optical density in the range over i line | wire may be 3 or more.

As a semi-transmissive film or light-shielding film which has the film | membrane structure of the said invention, the following specific correspondence is mentioned.

(Aspect 1)

The material on the substrate side in the semi-transmissive film or the light-shielding film according to Embodiment 1 is a material containing a large amount of oxygen as compared to the material on the upper side (constitution 3).

Specifically, when oxygen is added to the metal silicide (eg, molybdenum silicide (MoSi)), the etching rate is increased. Therefore, the substrate side (near the substrate) has an oxide of the metal silicide (eg, MoSi0) or metal silicide. Formed of a material of oxynitride (e.g., MoSiON (content of oxygen> content of nitrogen, i.e., oxygen rich)), and a laminated film of an oxide film of metal silicide and a metal silicide (for example, , Substrate / MoSi0 / MoSi), metal silicide oxynitride film (but oxygen content> nitrogen content, ie oxygen rich) and metal silicide laminated film (eg substrate / MoSiON / MoSi), substrate from substrate side From the side, a laminated film of an oxide film of metal silicide, a metal silicide film, and an oxynitride film of metal silicide (however, nitrogen content> oxygen content, that is, nitrogen rich) (for example, substrate / MoSiO / MoSi) / MoSiON) A substrate / MoSiO / MoSi / MoSiON film is a type which has an antireflection function.

Alternatively, when nitrogen is added to the metal silicide, the etching rate is lowered. Therefore, the laminated film of the metal silicide film and the nitride film of the metal silicide (for example, substrate / MoSi / MoSiN) from the substrate side, and the metal silicide film and metal silicide from the substrate side To a laminated film (eg, substrate / MoSi / MoSiON (however, nitrogen content> oxygen content, ie, nitrogen rich)) of an oxynitride film (content of nitrogen> content of oxygen, that is, nitrogen rich). The film | membrane of a structure is a type which gave antireflection function.

The film | membrane which concerns on Embodiment 1 can be obtained by controlling the gas system of sputtering gas using the sputtering target containing a metal and silicon.

In the film structure, the composition may be changed step by step or may be changed continuously (constitution 6).

In the film structure, the ratio of the region of the material having a relatively high wet etching rate on the substrate side (near the substrate) to the thickness of the entire translucent film is set to 0.2 to 0.5, and the overall light blocking film As for the ratio of the area | region which consists of a material with a relatively quick wet etching rate on the board | substrate side (right side of a board | substrate) to thickness, 0.05-0.3 are preferable.

(Aspect 2)

The semi-transmissive film or the light-shielding film according to Embodiment 2 is an additive element which accelerates the etching rate by wet etching to a material composed of molybdenum and silicon (molybdenum silicide), which is aluminum, titanium, silver, phosphorus, tungsten, tantalum and boron. Molybdenum having a relatively low etching rate due to wet etching compared to the material on the substrate side, wherein the substrate side is composed (formed) with a material to which one or two or more additional elements selected from gallium and indium are added. A film made of (molded) a molybdenum silicide-based material containing silicon and silicon (constituent 4).

In Embodiment 2, additional elements (such as alloy forming elements or other elements) that accelerate the wet etching rate to molybdenum silicide (MoSi), for example, aluminum, titanium, silver, phosphorus, tungsten, tantalum, boron, gallium A material to which one or two or more additional elements selected from among indium and the like is added is formed on the substrate side (near the substrate). More specifically, for example, the substrate / MoSiAl / MoSi, the substrate / MoSiAl / MoSi / MoSiON (however, nitrogen content> oxygen content, that is, nitrogen rich). The film | membrane of this board | substrate / MoSiAl / MoSi / MoSiON (it is content of nitrogen> content of oxygen, ie, nitrogen rich) is a type which provided the antireflection function.

The film according to Embodiment 2 can be obtained by controlling the gas system in the sputtering gas by using a sputtering target containing molybdenum, silicon and an additional element, and containing molybdenum and silicon (not including the additional element). have.

In the film structure, the composition may be changed step by step or may be changed continuously (constitution 6).

As described above, in the film structure, the ratio of the region made of the material having a relatively high wet etching rate on the substrate side (near the substrate) to the thickness of the entire translucent film is 0.2 to 0.5, and As for the ratio of the area | region which consists of a material with a relatively fast wet etching rate on the board | substrate side (right side of a board | substrate) which occupies for the thickness of the whole light shielding film, 0.05-0.3 are preferable.

(Aspect 3)

The semi-transmissive film or the light-shielding film according to Embodiment 3 is subjected to wet etching by changing the content ratio of metal and silicon composed of a material containing metal and silicon toward the depth direction of the film of the semi-translucent film or the light-shielding film. The film which controlled the etching rate by this is comprised, The board | substrate side is comprised from the material containing the metal and silicon which increased the metal content to 30 atomic% or more, and the upper side was the metal which increased the silicon content to 80 atomic% or more. A film composed of a material containing silicon and silicon (Structure 5).

The film | membrane which concerns on Embodiment 3 can be obtained by using the some metal silicide target which changed the content ratio of the metal and silicon in the metal silicide target containing a metal and silicon.

As described above, in the film structure, the ratio of the region made of the material having a relatively high wet etching rate on the substrate side (near the substrate) to the thickness of the entire translucent film is 0.2 to 0.5, and As for the ratio of the area | region which consists of a material with a relatively fast wet etching rate on the board | substrate side (right side of a board | substrate) which occupies for the thickness of the whole light shielding film, 0.05-0.3 are preferable.

In the present invention, as a material constituting each layer in the semi-translucent film or the light-shielding film having the film structure of the present invention, as the metal, molybdenum (Mo), tantalum (Ta), tungsten (W), titanium Molybdenum silicide (MoSi), tantalum silicide (TaSi), tungsten silicide (WSi), titanium silicide (TiSi) using (Ti) or the like, and at least one of oxygen, nitrogen, and carbon to MoSi, TaSi, WSi, TiSi And a material containing the same.

The semi-transmissive film having the film structure of the present invention is suitable for use as a semi-transmissive film in a gray tone mask of a semi-transmissive film-type (pre-mounted) type.

In addition, the semi-transmissive film which has the film | membrane structure of the said invention can be used also as a semi-transmissive film | membrane in the gray-tone mask of the type (post-mounted) of a semi-transmissive film | membrane.

In the mask blank and mask for manufacturing the FPD device according to the present invention, at least, there is included an aspect in which the semi-transparent film for the gray tone mask and the light-shielding film according to the present invention are arranged on the light-transmitting substrate in no order. That is, the aspect which forms a light-shielding film | membrane for the purpose of blocking an exposure wavelength apart from a semi-transmissive film | membrane is included. Specifically, for example, as shown in FIG. 5 (1), the semi-transmissive film 11 for light shielding and the light-shielding film 12 are formed in this order on the light-transmissive substrate 10. These films are patterned to form a semi-transparent film underlay formed by forming a semi-transmissive film pattern for a gray tone mask and a light-shielding film pattern, and as shown in FIG. 5 (2), light-shielding properties are provided on the light-transmissive substrate. A semi-transmissive film-laid type formed by forming a film and a semi-transmissive film for a gray tone mask in this order and patterning these films to form a light-shielding film pattern and a semi-transmissive film pattern for a gray tone mask may be cited. have.

As the material of the light-shielding film in these mask blocking and masks, chromium, nitride of chromium, carbide of chromium, fluoride of chromium, and the material containing at least one of them are preferable, for example.

Moreover, the light-shielding film which has the film | membrane structure of the said invention is suitable for use as a light-shielding film (it may have antireflection function) which is a substitute for the Cr-based light-shielding film material in a large mask blank for FPDs, and a mask. .

In the mask blank and mask for manufacturing the FPD device according to the present invention, an aspect having at least the light-shielding film according to the present invention is included on the light transmissive substrate. Specifically, for example, as shown in FIG. 4, the light-transmissive film 12 is formed on the light-transmissive substrate 10, and patterned thereon, whereby the gray tone pattern 12a and the general light-shielding film pattern are provided. The aspect formed by forming (12b) is included.

In the present invention, as the etching liquid (etchant) used for wet etching of the semi-translucent film or the light-shielding film having the film structure of the present invention, ammonium hydrogen fluoride, ammonium fluoride, hydrofluoric acid, boric fluoride acid, hydrofluoric acid and the like The aqueous solution which mixed the fluorine compound and oxidizing agents, such as hydrogen peroxide, acetic acid, and sulfuric acid, is mentioned.

In the present invention, examples of the light transmissive substrate include substrates such as synthetic quartz, soda lime glass, and alkali free glass.

In the present invention, mask blanks and masks for manufacturing FPD devices include mask blanks and masks for manufacturing FPD devices, such as LCD (liquid crystal display), plasma display, organic EL (electroluminescence) display, and the like. Can be.

Here, the mask for manufacturing LCD includes all the masks necessary for manufacturing LCD, for example, a TFT (thin film transistor), especially a TFT channel part or a contact hole part, a low temperature polysilicon TFT, a color filter, a reflecting plate (black matrix), etc. Included is a mask for forming. Other masks for manufacturing display devices include all masks necessary for manufacturing organic EL (electroluminescent) displays, plasma displays and the like.

The photomask for manufacturing the FPD device according to the present invention is prepared using a mask blank for manufacturing the FPD device according to the present invention, and is formed on a mask blank by wet etching and / or light-shielding. The film is patterned to produce a mask pattern (constitution 7).

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on an Example.

(First embodiment)

The light-shielding film was formed on a large glass substrate (synthetic quartz (QZ) 10 mm thick, size 850 mm x 1200 mm) using a large inline sputtering device. Specifically, a film made of molybdenum, silicon, and oxygen (MoSi0) was formed to a film thickness of 100 angstroms using Ar and O2 as sputtering gases using a target of Mo: Si = 1: 1 (atomic% ratio). Then, using the same target, using Ar as a sputtering gas, a film (MoSi) made of molybdenum and silicon was formed to a film thickness of 1000 angstroms, and a mask blank having a light shielding film was produced on a transparent substrate. . At this time, the thickness of each layer and the etching rate ratio of each layer were adjusted to the predetermined range so that it might be suitable to implement | achieve both the characteristics of (i) and (ii) mentioned above. In addition to this, the film thickness of each layer and the composition of each layer were adjusted so that the optical density in the range over i line | wire to g line | wire which is a wavelength of an exposure light source may be three or more.

After the cleaning process (pure, room temperature) using the mask blank produced by the above, a resist is apply | coated using a slit coater apparatus, a resist pattern is formed by image development, and this resist pattern is used as a mask and light-shielding The film is patterned by wet etching with an aqueous solution of ammonium bifluoride and hydrogen peroxide (etchant) to form a normal pattern 12b having a width of 5 μm and a gray tone pattern having a width of 1 μm (a fine light-shielding pattern below the resolution limit of a large FPD exposure machine). And a large-size mask for FPD having a pattern (12a) composed of micro-transmissive portions (see FIG. 4).

As a result of observing the large-sized mask for FPD with a scanning electron microscope (SEM), it was confirmed that any mask pattern had a cross-sectional shape as a whole as shown in FIG. 1, and that the pattern precision was inferior to that of the Cr-based material.

Moreover, when the FPD device was produced using the said large sized mask for FPD, and display unevenness was confirmed, it confirmed that there was no display unevenness in the produced FPD device.

In addition, when the observation by a scanning electron microscope (SEM) and the measurement of the transmittance | permeability were performed with respect to the said large sized mask for FPD, the damage of the glass substrate surface considered to be due to the etching effect of the glass substrate surface by the said etchant. There was no occurrence of surface roughness and no decrease in transmittance was observed.

In addition, except that the glass substrate was changed to soda-lime glass, the same investigation was conducted as in the first embodiment, and as a result, the damage and the surface roughness of the surface of the glass substrate, which are thought to be due to the etching operation of the surface of the glass substrate by the etchant, were investigated. There was no roughness or the occurrence of turbidity on the surface of the glass substrate, and no decrease in transmittance was observed.

(Comparative Example 1)

The light-shielding film was formed on a large glass substrate (synthetic quartz (QZ) 10 mm thick, size 850 mm x 1200 mm) using a large inline patterning device. Specifically, using a target of Mo: Si = 1: 2 (atomic% ratio), using Ar as a sputtering gas, a film (MoSi) made of molybdenum and silicon was formed at a film thickness of 1000 angstrom, and then Using the same target, a film made of molybdenum, silicon, and oxygen (MoSi0) was formed with a film thickness of 400 angstroms using Ar and O2 as sputtering gases, and a mask blank having a light shielding film was produced on a transparent substrate. . At this time, the film thickness of each layer and the composition of each layer were adjusted so that the optical density in the range over i line | wire to g line | wire which is a wavelength of an exposure light source may be three or more.

After the cleaning process (pure, room temperature) using the mask blank produced by the above, a resist is apply | coated using a slit coater apparatus, a resist pattern is formed by image development, and this resist pattern is used as a mask and light-shielding The film is patterned by wet etching with an aqueous solution of ammonium bifluoride and hydrogen peroxide (etchant) to form a normal pattern 12b having a width of 5 μm and a gray tone pattern having a width of 1 μm (a fine light-shielding pattern below the resolution limit of a large FPD exposure machine). And a large-size mask for FPD having a pattern (12a) composed of micro-transmissive portions (see FIG. 4).

As a result of observing the large-sized mask for FPD with a scanning electron microscope (SEM), as for the mask pattern, the edges are formed as shown in FIG. 2 and the cross-sectional shape is bad, and the pattern precision by wet etching is worse than that of Cr-based material. Confirmed that.

Moreover, when the FPD device was produced using the said large sized mask for FPD, and the display unevenness was confirmed, it was confirmed that the produced FPD device has display unevenness considered to be the cause of a bad pattern cross-sectional shape and a pattern precision. In addition, the display nonuniformity confirmed that it was easy to come out from the gray-tone pattern (pattern consisting of the fine light-shielding pattern below the resolution limit of a large FPD exposure machine and a micro-transmissive part) 12a of 1 micrometer width.

In addition, when the observation by a scanning electron microscope (SEM) and the measurement of the transmittance | permeability were performed with respect to the said large sized mask for FPD, the damage of the glass substrate surface considered to be due to the etching effect of the glass substrate surface by the said etchant. The occurrence of surface roughness was confirmed, and the decrease in transmittance was also confirmed.

In addition, except that the glass substrate was replaced with soda lime glass, the same result as in the first comparative example was investigated, and as a result of the damage and surface roughness of the surface of the glass substrate, which is thought to be due to the etching action of the surface of the glass substrate by the etchant. Roughness and the occurrence of turbidity on the surface of the glass substrate were confirmed, and a decrease in the transmittance was also confirmed.

(2nd Example)

On the large size glass substrate (10 mm thickness of synthetic quartz (QZ), size 850 mm x 1200 mm), the semi-transmissive film for gray tone masks was formed using the large size inline sputtering apparatus. Specifically, a film made of molybdenum, silicon, and oxygen (MoSi20) was formed to a film thickness of 40 Angstroms using Ar and O2 as sputtering gases using a target of Mo: Si = 1: 1 (atomic% ratio). Then, using the same target, using Ar as a sputtering gas, a film (MoSi2) made of molybdenum and silicon was formed to a film thickness of 60 angstroms, and a mask having a translucent film for gray tone mask on a transparent substrate. Made a blank. At this time, the thickness of each layer and the etching rate ratio of each layer were adjusted to the predetermined range so that it might be suitable for realizing both the above-mentioned characteristics (i) and (ii). In addition, the film thickness of each layer and the composition of each layer were adjusted so that the transmittance | permeability in the range over i line | wire to g line | wire which is a wavelength of an exposure light source may be 40%.

Next, the Cr light-shielding film was formed on the said semi-transmissive film for gray tone masks using the large size inline sputtering apparatus. The film formation is performed by using a Cr target, first using Ar and N2 as a sputtering gas, 150 angstroms of CrN film, followed by Ar and CH4 gas as sputtering gas, 620 angstroms of CrC film (light-shielding film), and subsequently, A 250 angstrom and a CrON film (film surface antireflection film) were continuously formed using NO gas as a sputtering gas, and the large mask blank for FPD was produced.

After the cleaning process (pure, room temperature) using the mask blank produced by the above, a resist is apply | coated using a slit coater apparatus, a resist pattern is formed by image development, this resist pattern is used as a mask, and the Cr difference The photosensitive film is patterned by wet etching with an aqueous solution of di-celium ammonium acetate and perchloric acid (etchant), and then the MoSi-based translucent film is patterned by wet etching with an aqueous solution of ammonium bifluoride and hydrogen peroxide (etchant). A large-sized mask for FPD having a Cr light-shielding film pattern and a MoSi semi-transmissive film pattern of a semi-transmissive film-laying type as shown in (1) of was manufactured.

As a result of observing the large-sized mask for FPD with a scanning electron microscope (SEM), as for all mask patterns, it becomes a cross-sectional shape as a whole as shown in FIG. 1, and the precision of MoSi semi-transmissive film pattern is also inferior to Cr type material. Confirmed that there is no.

Moreover, when the FPD device was produced using the said large sized mask for FPD, and display unevenness was confirmed, it confirmed that there was no display unevenness in the produced FPD device.

In addition, when the observation by a scanning electron microscope (SEM) and the measurement of the transmittance | permeability were performed with respect to the said large sized mask for FPD, the damage of the glass substrate surface considered to be due to the etching effect of the glass substrate surface by the said etchant. There was no occurrence of surface roughness and no decrease in transmittance was observed.

In addition, except that the glass substrate was replaced with soda lime glass, the result of the investigation in the same manner as in the second embodiment showed that the glass substrate was damaged due to the etching effect of the surface of the glass substrate, which is thought to be due to the etching action of the surface of the glass substrate. There was no occurrence of roughness or turbidity on the surface of the glass substrate, and no decrease in transmittance was observed.

(Third Embodiment)

In the above-described first embodiment, as the light shielding film, a film made of molybdenum and silicon (MoSi 2 film, Mo: 33 atomic%, Si: 67 atomic%) from the substrate side, and a film made of molybdenum and silicon (MoSi 4 film) , Mo: 20 atomic%, Si: 80 atomic%) in the same manner as in the first embodiment, a large size mask blank for FPD and a large size mask for FPD were produced.

As a result of observing the large-sized mask for FPD with a scanning electron microscope (SEM), it was confirmed that any mask pattern had a cross-sectional shape as a whole in FIG. 1 and that the pattern precision was inferior to that of the Cr-based material.

Moreover, when the FPD device was produced using the said large sized mask for FPD, and display unevenness was confirmed, it confirmed that there was no display unevenness in the produced FPD device.

In addition, when the observation by a scanning electron microscope (SEM) and the measurement of the transmittance | permeability were performed with respect to the said large sized mask for FPD, the damage of the glass substrate surface considered to be due to the etching action of the glass substrate surface by the said etching, There was no occurrence of surface roughness and no decrease in transmittance was observed.

In addition, except that the glass substrate was changed to soda lime glass, the result of the investigation in the same manner as in the first embodiment showed that damage of the surface of the glass substrate and surface roughness, which are thought to be due to the etching action of the surface of the glass substrate by the etchant, were observed. There was no occurrence of roughness or turbidity on the surface of the glass substrate, and no decrease in transmittance was observed.

(Example 4)

In the above-described first embodiment, as the light shielding film, the film is made of a laminated film of a film made of molybdenum, aluminum and silicon (MoSiAl film) and a film made of molybdenum and silicon (MoSi film) from the substrate side. In the same manner as in Example 1, a large mask blank for FPD and a large mask for FPD were produced.

As a result of observing the large-sized mask for FPD with a scanning electron microscope (SEM), it was confirmed that any mask pattern had a cross-sectional shape as a whole in FIG. 1 and that the pattern precision was inferior to that of the Cr-based material.

Moreover, when the FPD device was produced using the said large sized mask for FPD, and display unevenness was confirmed, it confirmed that there was no display unevenness in the produced FPD device.

In addition, when the observation by a scanning electron microscope (SEM) and the measurement of the transmittance | permeability were performed with respect to the said large sized mask for FPD, the damage of the glass substrate surface considered to be due to the etching effect of the glass substrate surface by the said etchant. There was no occurrence of surface roughness and no decrease in transmittance was observed.

In addition, except that the glass substrate was changed to soda lime glass, the result of the investigation in the same manner as in the first embodiment showed that damage of the surface of the glass substrate and surface roughness, which are thought to be due to the etching action of the surface of the glass substrate by the etchant, were observed. There was no occurrence of roughness or turbidity on the surface of the glass substrate, and no decrease in transmittance was observed.

As mentioned above, although this invention was demonstrated when a preferable Example was given, this invention is not limited to the said Example.

Therefore, according to the present invention, it is possible to solve the problem of damage occurring on the surface of the glass substrate, resulting in roughness of the surface or decrease in transmittance, thereby achieving high quality of the large-sized mask blank and mask for the FDD.

Claims (14)

delete delete As a mask blank for manufacturing an FPD device which has at least one of the translucent film | membrane which has a function which adjusts the transmittance | permeability, and a light-shielding film | membrane on a translucent board | substrate, The semi-transmissive film or the light-shielding film is made of a metal silicide-based material containing a metal and silicon, The semi-transmissive film made of the metal silicide-based material or the light-shielding film made of the metal silicide-based material is configured such that the etching rate by wet etching is increased in the depth direction of the film of the translucent film or the light-shielding film, The semi-transmissive film or the light-shielding film is composed of a metal silicide-based material having a relatively high etching rate by wet etching, and the upper side thereof has a relatively high etching rate by wet etching compared to the material on the substrate side. Consists of a slow metal silicide-based material, The mask blank for manufacturing an FPD device characterized in that the material on the substrate side of the semi-transmissive film or the light-shielding film is a material containing a larger amount of oxygen than the material on the upper side thereof. As a mask blank for manufacturing an FPD device which has at least one of the translucent film | membrane which has a function which adjusts the transmittance | permeability, and a light-shielding film | membrane on a translucent board | substrate, The semi-transmissive film or the light-shielding film is made of a metal silicide-based material containing a metal and silicon, The semi-transmissive film made of the metal silicide-based material or the light-shielding film made of the metal silicide-based material is configured such that the etching rate by wet etching is increased in the depth direction of the film of the translucent film or the light-shielding film, The semi-transmissive film or the light-shielding film is composed of a metal silicide-based material having a relatively high etching rate by wet etching, and the upper side thereof has a relatively high etching rate by wet etching compared to the material on the substrate side. Consists of a slow metal silicide-based material, The semi-transmissive film or the light-shielding film is selected from aluminum, titanium, silver, phosphorus, tungsten, tantalum, boron, gallium, and indium, which are additive elements that accelerate the etching rate by wet etching to a material composed of molybdenum and silicon. The substrate side is constituted by a material to which one or more additional elements are added, and the upper side is formed of a molybdenum silicide-based material including molybdenum and silicon having a relatively slow etching rate by wet etching compared to the material on the substrate side. The mask blank for manufacturing an FPD device characterized by the above-mentioned film. As a mask blank for manufacturing an FPD device which has at least one of the translucent film | membrane which has a function which adjusts the transmittance | permeability, and a light-shielding film | membrane on a translucent board | substrate, The semi-transmissive film or the light-shielding film is made of a metal silicide-based material containing a metal and silicon, The semi-transmissive film made of the metal silicide-based material or the light-shielding film made of the metal silicide-based material is configured such that the etching rate by wet etching is increased in the depth direction of the film of the translucent film or the light-shielding film, The semi-transmissive film or the light-shielding film is composed of a metal silicide-based material having a relatively high etching rate by wet etching, and the upper side thereof has a relatively high etching rate by wet etching compared to the material on the substrate side. Consists of a slow metal silicide-based material, The semi-transmissive film or the light-shielding film is an etching rate by wet etching by changing the content ratio of the metal and silicon composed of a material containing a metal and silicon toward the depth direction of the film of the translucent film or the light-shielding film. The film | membrane which controlled the film | membrane, the board | substrate side is comprised from the material containing the metal and silicon which made the content of metal more than 30 atomic%, and the upper side was made into the metal and silicon which increased the content of silicon to 80 atomic% or more. It is a film | membrane comprised with the material containing, The mask blank for manufacturing FPD devices characterized by the above-mentioned. The method according to any one of claims 3 to 5, The composition of the semi-transmissive film or the light-shielding film is mask blank for manufacturing an FPD device, characterized in that it changes stepwise or continuously toward the depth direction of the film. A photomask for manufacturing an FPD device, wherein the semi-transmissive film or the light-shielding film is patterned by wet etching using the mask blank of any one of claims 3 to 5. delete The method according to any one of claims 3 to 5, A mask blank for manufacturing an FPD device, wherein a ratio of a region made of a material having a relatively high etching rate by wet etching on the substrate side that occupies the entire thickness of the semi-translucent film is 0.2 to 0.5. The method according to any one of claims 3 to 5, A mask blank for manufacturing an FPD device, wherein a ratio of a region made of a material having a relatively high etching rate by wet etching on the substrate side occupying the entire thickness of the light-shielding film is 0.05 to 0.3. The method according to any one of claims 3 to 5, The etching liquid used for the said wet etching is an aqueous solution which mixed the fluorine compound and the oxidizing agent, The mask blank for manufacturing an FPD device characterized by the above-mentioned. The method according to any one of claims 3 to 5, The mask blank is a mask that is exposed by exposure light including a wavelength across i-g lines when fabricating an FPD device after the semi-transmissive film and the light-shielding film are patterned by wet etching to form a photomask. A blank for manufacturing an FPD device, characterized in that it is blank. The method of claim 12, The transmittance | permeability in the range over the i line | wire to g line | wire of the said translucent film is 10 to 60%, The mask blank for manufacturing an FPD device characterized by the above-mentioned. The method of claim 12, The optical density in the range over the said i line | wire to the g line | wire of the said light-shielding film is 3 or more, The mask blank for manufacturing an FPD device characterized by the above-mentioned.

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