TWI789538B - Membrane complex and method for producing the same - Google Patents

Abstract

The coating composite of the present invention has a carbon film (A), a film part (B) surface-bonded to one side of the carbon film, and a frame part (C) arranged along the outer edge of the film part (B), And the element which comprises the said frame part (C) is contained in the said film part (B) as at least a part of its constituent elements. Preferably, the element constituting the frame portion (C) is one or more elements selected from the group consisting of silicon, zirconium, niobium, molybdenum, titanium, and tungsten. Preferably, the film portion (B) is at least one of a layer made of the same material as that of the frame portion (C), or a layer containing both elements constituting the frame portion (C) and carbon.

Description

Membrane complex and method for producing the same

The invention relates to a protective film complex and a manufacturing method thereof.

The miniaturization of semiconductor devices continues to develop year by year, and the pattern with a line width of about 45 nm is achieved by excimer exposure. In recent years, the industry has also required narrower patterns such as a line width of about 32 nm or less. In response to this, the industry is researching to change the exposure light to a shorter wavelength of extreme ultraviolet (EUV, Extreme Ultra Violet). In EUV lithography, the resist is exposed using EUV reflected by a mask (master mask, working mask, etc.) that reflects the exposure pattern. In addition, in the above photomask, a pellicle composite provided with a protective film for dust prevention is used (for example, Patent Document 1, Patent Document 2, etc.). As shown in FIG. 4 , the pellicle complex 1 of Patent Document 1 and Patent Document 2 is disposed on the pattern forming surface of the photomask 80, and includes a pellicle 25 functioning as a dustproof film, and a pellicle disposed on the pellicle 25. The frame part 40 of the outer edge. By bonding the pellicle composite 1 to the photomask 80 from the frame portion 40 side, the pattern formation surface can be protected from dust. In addition, the protective film 25 of Patent Document 1 is DLC (Diamond-like Carbon, diamond-like carbon), and the protective film 25 of Patent Document 2 is a graphene film or graphite film, and the protective film 25 and the frame portion 40 are made of an adhesive 70 engagement. [Prior Art Literature] [Patent Document]

Patent Document 1: Specification WO2014/188710 Patent Document 2: Japanese Patent Laid-Open No. 2015-18228

[Problem to be solved by the invention]

However, the above-mentioned pellicle complex has problems in terms of durability, outgassing, hydrogen radical resistance, and the like. The present invention is made focusing on the above situation, and its purpose is to improve at least one (preferably all) of durability, outgassing, and hydrogen radical resistance. [Technical means to solve the problem]

The inventors of the present invention have made intensive research to solve the above-mentioned problems. As a result, they have found that the reduction in durability or the generation of outgassing is caused by the adhesive, and a part of the coating is made of a carbon film, and the carbon film is placed on top of the carbon film. A film composed of specific elements is formed on the frame side, and if the two are surface-bonded, even without using an adhesive, the peel strength between the two can be maintained at a specified level or higher, and the hydrogen resistance of the coating can also be improved. Free radical property, and can also improve durability, reduce outgassing, etc., thereby completing the present invention. That is, the present invention is as follows. [1] A protective film composite, characterized in that it has: a carbon film (A), a film part (B) surface-bonded to one side of the carbon film, and a film part (B) arranged along the outer edge of the above-mentioned film part (B). The frame portion (C), and elements constituting the frame portion (C) are contained in the film portion (B) as at least a part of its constituent elements. [2] The coating composite as described in [1], wherein the element constituting the frame portion (C) is one or more elements selected from the group consisting of silicon, zirconium, niobium, molybdenum, titanium, and tungsten . [3] The pellicle composite as described in [1] or [2], wherein the above-mentioned film part (B) satisfies a layer of the same material as the frame part (C), or includes a material constituting the frame part (C). At least one of layers of both elements and carbon. [4] The coating composite according to any one of [1] to [3], wherein the carbon film (A) is directly bonded to the film part (B). [5] The coating complex according to any one of [1] to [4], wherein the carbon film (A) is a carbon film or a graphite film (A1). [6] A method of manufacturing the pellicle composite as described in any one of [1] to [5], wherein the single-layer layer on the substrate (C') made of the same material as the frame portion (C) is After heating the laminate with the carbonized raw material film (A') to form the carbonized raw material film (A') into a carbon film (A), the laminated body is etched from the substrate (C') side to leave the substrate (C') The frame part (C) is formed by making the outer edge thicker than the other part, and the film part (B) is formed by leaving the part other than the outer edge part. [7] A method of manufacturing the pellicle composite as described in any one of [1] to [5], wherein the single-layer layer on the substrate (C') made of the same material as the frame portion (C) is Heating the layered body with the carbonized raw material film (A') to turn the carbonized raw material film (A') into a carbonaceous film or a graphite film (A1) and a layer containing both the elements constituting the frame (C) and carbon 2 layers of (B2), forming the above-mentioned carbon film (A) and the above-mentioned film part (B), thereafter, The outer edge of the substrate (C') is left as the frame portion (C), and the above-mentioned laminate is etched from the substrate (C') side. [8] The method for producing a pellicle composite as described in [7], wherein the substrate other than the remaining portion of the frame portion (C) is etched while remaining, and the remaining portion is combined with the above-mentioned layer ( B2) is collectively referred to as the above-mentioned film part (B). [9] The method for producing a pellicle composite as described in [7], wherein the substrate (C') other than the remaining portion of the frame portion (C) is completely removed by the etching. [Effect of Invention]

According to the coating composite of the present invention, at least one (preferably all) of durability, outgassing, and hydrogen radical resistance can be improved.

1. Terms Explain the meaning of terms used in this manual. (1) Extreme Ultraviolet (EUV, Extreme Ultra Violet) In this specification, EUV refers to light with a wavelength of 5 nm to 30 nm, preferably 5 nm to 13.5 nm. The pellicle composite of the present invention is preferably used in lithography using the EUV.

(2) Membrane Complex The pellicle composite system is used to protect the pattern surface of the photomask reflecting the exposure pattern, including a pellicle and a frame (pellet frame) arranged on the outer edge of the pellicle. The shape of the pellicle is not particularly limited, and may be appropriately selected from circular, elliptical, polygonal, and the like. Preferable shapes are quadrilaterals such as squares and rectangles.

(3) protective film The pellicle refers to the membrane portion of the pellicle complex. In the present invention, it is composed of a carbon film (A) and a film portion (B). About film part (B), it demonstrates below.

(4) Carbon film (A) The carbon film (A) refers to a film substantially composed of carbon atoms, and is used as a constituent member of the above coating in the present invention. The thickness of the carbon film is, for example, not more than 1000 nm, preferably not less than 5 nm and not more than 100 nm, more preferably not less than 5 nm and not more than 50 nm, especially preferably not less than 5 nm and not more than 30 nm. The area of the carbon film is, for example, not less than 100 cm ² , preferably not less than 120 cm ² , more preferably not less than 150 cm ² and not more than 3000 cm ² . The shape of the carbon film is not particularly limited, but it is preferably a rectangle or a square, and the length of one side is, for example, more than 10 cm, preferably more than 15 cm, and more preferably more than 20 cm. The transmittance of the carbon film for EUV at a wavelength of 13.5 nm is, for example, not less than 55% and not more than 97%, preferably not less than 74% and not more than 97%, more preferably not less than 84% and not more than 97%. The surface roughness (Sa) of the carbon film is, for example, not less than 0.1 nm and not more than 500 nm. The surface roughness is preferably at least 0.2 nm, more preferably at least 0.5 nm, further preferably at least 1 nm, and preferably at most 200 nm, more preferably at most 100 nm, further preferably at most 50 nm. In addition, the surface roughness Sa means the arithmetic mean height obtained based on ISO25178. The smaller the surface roughness, the higher the EUV transmittance.

The carbon film includes a carbon film, a diamond-like carbon film (DLC), a graphene film, a graphite film, and the like, and the carbon film includes an amorphous carbon film, an amorphous carbon film, and the like. Preferred carbon films are carbonaceous films, graphene films, graphite films, etc., more preferably carbonaceous films and graphite films (A1).

A carbonaceous film can be distinguished from a graphene film or a graphite film based on the results of laser Raman measurement. In the case of laser Raman spectroscopy, the G band caused by the graphite structure appears around 1575~1600 cm ^-1 , and the D frequency band caused by the amorphous carbon structure appears around 1350~1360 cm ^-1 . In the Raman spectrum, the ratio of the intensity of the G band (I(G)) to the intensity of the D band (I(D)) (I(D)/I(G); D/G band intensity ratio) exceeds 0.5 and is classified A carbonaceous film with a D/G band intensity ratio of 0.5 or less is classified as a graphene film or a graphite film.

The D/G band intensity ratio of the carbonaceous film is preferably 2.5 or less, more preferably 0.7 or more and 1.5 or less, particularly preferably 0.9 or more and 1.3 or less. The D/G frequency band intensity ratio of typical amorphous carbon (Glassy carbon) produced by vapor deposition or sputtering is about 1.8~2.0. A carbonaceous film having a D/G band intensity ratio of 1.5 or less can be obtained or produced by an appropriate method, for example, preferably produced by carbonizing an aromatic polyimide film. The above-mentioned aromatic polyimide film is, for example, preferably a film using a chemical curing method using a dehydrating agent represented by an acid anhydride such as acetic anhydride, or picoline, quinoline, isoquinoline, pyridine, etc. Tertiary amines are used as imidization accelerators for polyamides produced by combining pyromellitic dianhydride with 4,4-diaminodiphenyl ether (ODA) and p-phenylenediamine (PDA). acid for imide conversion. The carbonization treatment (heat treatment) of the aromatic polyimide film only needs to be carried out at 900-2000°C for 15-30 minutes in an inert gas atmosphere such as nitrogen, argon or a mixture of argon and nitrogen. The rate of temperature increase to the carbonization treatment temperature is not particularly limited, and is, for example, 5° C./min or more and 15° C./min or less. After carbonization heat treatment, what is necessary is just to cool to room temperature by natural cooling etc.

The thickness of the carbonaceous film can be selected from the same range as the thickness of the above-mentioned carbon film. The surface roughness (Sa) of the carbonaceous film is also the same as the surface roughness (Sa) of the above-mentioned carbon film.

The D/G band intensity ratio of the graphene film or the graphite film is 0 to 0.5, preferably 0 to 0.1, more preferably 0 to 0.05.

Examples of the above-mentioned graphene film include a graphene single-layer film or a graphene multilayer film with a thickness of less than 5 nm. The graphite film is a film with a thickness of 5 nm or more, and the preferred range of its thickness is the same as that of the carbon film. The surface roughness (Sa) of the graphite film is the same as the surface roughness (Sa) of the above-mentioned carbon film.

Graphene film or graphite film can be formed by the temperature higher than the carbonization temperature, for example, more than 2000°C and less than 3300°C, preferably more than 2200°C and less than 3200°C, more preferably more than 2400°C and less than 3000°C. The carbonaceous film obtained from the aromatic polyimide film is obtained by heat treatment.

(5) Protective film frame The pellicle frame refers to the frame portion formed on the pellicle and used to cover the photomask with the pellicle complex. The pellicle frame may have ventilation holes in order to stabilize the air pressure in the exposure device and in the pellicle complex. As the material of the above-mentioned protective film frame, elements such as cesium, potassium, sodium, rubidium and the like that form interlayer compounds with the carbon film; elements such as nickel, bismuth, and iron that dissolve (solid solution) or dissolve in carbon, etc. Preferably, it contains elements including silicon, zirconium, niobium, molybdenum, titanium, and tungsten. Silicon, molybdenum, titanium, tungsten, etc. are elements that form metal carbides (metal carbides), which are superior to elements such as zirconium and niobium that are not easy to react with carbon atoms. These elements are preferably the most numerous elements among the elements constituting the frame (excluding carbon, hydrogen, oxygen, and nitrogen). The material of the protective film frame is preferably a semi-metal or metal such as silicon, zirconium, niobium, molybdenum, titanium, and tungsten, more preferably a metal such as zirconium, niobium, molybdenum, titanium, and tungsten.

2. Cuticle complex Hereinafter, the pellicle complex 1 of the present invention will be described in detail with reference to the illustrated examples. In addition, the same code|symbol is attached|subjected to the same component, and duplication of description is avoided. Fig. 1 (a) is a schematic sectional view showing an example of the pellicle complex 1 of the present invention, as the pellicle complex 1 (2) of the example has a carbonaceous film (A1) 21 as a carbon film (A) 20, And the frame portion (C) 40 provided along the outer edge of the carbon film 20 (21). Moreover, the above-mentioned pellicle composite 2 has a film portion (B) 30 surface-bonded to one side of the carbon film (A) 20 (the side where the frame portion (C) 40 exists), and the film portion (B) of the illustrated example ) 30 is a film part (hereinafter referred to as "homogeneous film" (B1)) 31 made of the same material as the frame part (C) 40 and integrated with the frame part (C) 40 . If the film portion (B) 30(31) and the carbon film (A) 20(21) are bonded, the two are directly bonded, so even without using an adhesive, the peel strength between the two can be maintained at a specified level. above. In addition, it is possible to prevent durability reduction, outgassing, etc. caused by adhesives. Furthermore, since the carbon film 20 ( 21 ) is protected by the film portion 30 ( 31 ), hydrogen radical resistance can also be improved.

The thickness of the carbon film (A) 20 (in the illustrated example, the thickness of the carbon film (A1) 21) is as described in the column of terms. The thickness of the film portion (B) 30 (in the illustrated example, the thickness of the homogeneous film (B1) 31 ) is, for example, not less than 0.5 nm and not more than 100 nm, preferably not less than 0.5 nm and not more than 10 nm, more preferably 0.5 nm Above and below 5 nm.

The surface roughness of the carbon film (A) 20 (in the illustrated example, the surface roughness of the carbonaceous film (A1) 21 ) is as described in the column of terms. The surface roughness mentioned here refers to the roughness of the outer surface side (the side opposite to the contact surface with the film portion 30 ) of the carbon film (A) 20 . The surface roughness (Sa) of the outer surface of the film portion (B) 30 (in the example of the figure, the homogeneous film (B1) 31) (that is, the surface roughness of the side not in contact with the carbon film (A) 20 ) is, for example, 0.1 nm to 1000 nm, preferably 0.1 nm to 500 nm, more preferably 0.1 nm to 200 nm. The smaller the surface roughness, the higher the EUV transmittance. The bonding strength between the carbon film (A) 20 and the film portion (B) 30 is sufficient as long as the strength of the bonding between the two is not peeled off during manufacture or use of the pellicle composite 1 . Preferably, the strength is such that material failure (for example, material failure of the carbon film (A) 20 ) occurs preferentially over interface failure during the peeling test.

The film portion (B) 30 does not need to be made of the same material as the frame portion (C) 40 , as long as it contains elements constituting the frame portion (C) 40 as at least a part of its constituent elements. For example, regarding the pellicle complex 3 (1) of Fig. 1(b), the above-mentioned film portion (B) 30 has a two-layer structure, and the two-layer structure is composed of a homogeneous film (B1) 31 on the side of the frame portion (C) 40 , and a film on the side of the carbonaceous film (A1) 21 (hereinafter referred to as "film containing frame elements and carbon" (B2)) 35. And this film (B2) 35 contains both the element which comprises the frame part (C)40, and carbon. The film (B2) 35 improves the bondability with the carbon film (A) 20 (in the illustrated example, the carbon film (A1) 21) by including carbon, and the film (B2) 35 improves the bondability with the carbon film (A1) 21 by including the frame portion (C ) 40 constituent elements, thereby improving the bondability with the frame portion (C) 40 .

As the film (B2) 35 containing a frame element and carbon, various films can be exemplified depending on elements constituting the frame. For example, when the element constituting the frame (hereinafter, sometimes referred to as "frame element") is a metal element or a semi-metal element, a metal carbide film or a semi-metal carbide film may be mentioned, and these may include metal carbides. , semi-metallic carbide, etc. layer. Also, it may be a layer containing an interlayer compound of a frame element and a carbon film, or may be a layer in which carbon is solid-dissolved in a frame element. A metal carbide film is preferred. The formation of the metal carbide film can be measured by mapping the element distribution obtained by scanning transmission electron microscopy (STEM, Scanning transmission electron microscopy) and energy dispersive X-ray analysis (EDS, Energy dispersive X-ray spectrometry). The measurement system uses a laser engraving machine to cut out a few millimeters square film composite. After embedding the cut-out pellicle complex in resin such as epoxy resin, it is cut together with the resin to expose the cross section of the pellicle complex, and processed into a cross-sectional TEM (Transmission Electron Microscope, transmission electron microscope) ) samples for measurement. The cutting of the cross-section is not a mechanical treatment such as grinding or cutting that affects the shape of the cross-section. It is more ideal such as focused ion beam (FIB, Focused Ion Beam) or electron beam (EB, Electron Beam), Ar ion beam (Ar Ion Beam) ) and other methods that can perform cross-section processing with high precision. STEM/EDS analysis is performed on the cross-sectioned samples to confirm the formation of the metal carbide film and measure the film thickness. At the same time, it can also confirm the carbon film and homogeneous film and measure the film thickness.

When the film part (B) 30 has a two-layer structure, the total thickness of the two layers is the same as the thickness of the above-mentioned film part (B) 30 . In addition, in the film portion (B) 30 of the two-layer structure, the thickness of the film on the side of the frame portion (C) 40 (in the illustrated example, the homogeneous film (B1) 31) is, for example, 0.3 nm to 60 nm. Preferably, it is not less than 0.3 nm and not more than 6 nm, more preferably not less than 0.3 nm and not more than 3 nm. In the film part (B) 30 of the two-layer structure, the film on the side of the carbon film (A) 20 (in the illustrated example, the film (B2) 35 containing frame element and carbon) has a thickness of, for example, 0.2 nm or more and 40 nm or less, preferably 0.2 nm or more and 4 nm or less, more preferably 0.2 nm or more and 2 nm or less.

The film portion (B) 30 of the pellicle composite 4 illustrated in FIG. 1( c ) includes a film ( B2 ) 35 including a frame element and carbon. Homogeneous membrane (B1) 31 is not necessary, as shown in the example of this figure.

The pellicle composite 5 of FIG. 1( d ) is obtained by changing the carbonaceous film ( A1 ) 21 of the pellicle composite 2 of FIG. 1 ( a ) into a graphite film ( A1 ) 22 . The pellicle complex 6 of FIG. 1( e ) is obtained by changing the carbonaceous film ( A1 ) 21 of the pellicle complex 3 of FIG. 1 ( b ) into a graphite film ( A1 ) 22 . The pellicle complex 7 of Fig. 1(f) is obtained by changing the carbonaceous film (A1) 21 of the pellicle complex 4 of Fig. 1(c) into a graphite film (A1) 22. As shown in these figures, the carbon film (A) 20 can be a carbon film (A1) 21 or a graphite film (A1) 22 . Furthermore, as described in the column of terms, as long as the film is substantially composed of carbon atoms, various films can be used as the carbon film (A) 20 .

3. Manufacturing method Fig. 2 is a schematic flow chart for illustrating the manufacturing method of the pellicle complexes 2-4 of Fig. 1(a)-(c). In this production example, first, the first laminate 60 is produced on a single-layer carbonized raw material film (A') 50 having a substrate (C') 45 made of the same material as the frame portion 40 . As the carbonization raw material film (A') 50, a well-known carbonization raw material can be used, Preferably the above-mentioned aromatic polyimide film can be used.

The obtained first laminate 60 is heated at a carbonization temperature (when the carbonization raw material film (A') 50 is an aromatic polyimide film, for example, about 900 to 2000° C.) (carbonization step : S11), thereby, the second laminated body 61 in which the carbonized raw material film (A') 50 becomes the carbonaceous film (A1) 21 can be obtained. By masking the outer edge of the substrate (C') of the second laminate 61 and performing etching (etching step: S13) to form the frame portion (C) 40 and the film portion (B) 30, a protective film can be produced. Complex 2. The film portion (B) 30 is removed by etching, and a part of the substrate (C′) remains as the homogeneous film (B1) 31 . Details of the etching method are described below.

In the carbonization step of the first laminate 60, depending on the carbonization conditions (for example, heating at 1000°C or higher when the carbonization raw material film (A') 50 is aromatic polyimide), A case where the film (B2) 35 containing frame element and carbon is formed not only on the carbonaceous film (A1) 21 but also on the interface side with the substrate (C′) 45 (carbonization step: S12 ). The product of the carbonization step S12 (the third layered body 62) can also be processed by treating the above-mentioned second layered body 61 under carbonization conditions stronger than the manufacturing conditions (higher temperature, longer time, etc.). and manufactured (carbonization step: S16). The frame portion (C) 40 and the film portion ( B) 30, the pellicle complex 3 can be manufactured. By further enhancing the etching conditions, the homogeneous film (B1) 31 of the film portion (B) 30 can also be removed (etching step: S15), so that the pellicle complex 4 can be produced.

Furthermore, depending on the type of the carbonaceous film (A1) 21, the above-mentioned first laminated body 61 can also be formed directly (that is, without a carbonization step) by vapor deposition or sputtering. In addition, the pellicle complex 3 can also be produced by subjecting the pellicle complex 2 to carbonization treatment of the same intensity as in step S12 or S16 (carbonization step: S17).

Fig. 3 is a schematic flow chart for illustrating the manufacturing method of the pellicle complexes 5-7 of Fig. 1(d)-(f). In this production example, the third laminate 62 obtained in the production example of FIG. The carbonaceous film (A1) 21 of the laminate 62 is changed to the fourth laminate 63 of the graphite film (A1) 22 . The fourth laminate 63 can also be processed by treating the first laminate 60 at the graphitization temperature (graphitization step: S22), or by treating the second laminate 61 at the graphitization temperature ( Graphitization step: S23) and manufacture. And, by processing the obtained fourth laminated body 63 in the same etching step as the above-mentioned step S14 (etching step: S24), or by processing the obtained fourth laminated body 63 in the same etching step as the above-mentioned step S15 Body 63 is processed (etching step: S25), and pellicle complex 6 or pellicle complex 7 can be manufactured.

On the other hand, by forming the graphite film (A1) 22 on one side of the substrate (C') 45 by vapor deposition or sputtering, a film (B2) 35 that does not interpose frame elements and carbon can be formed. On the other hand, the fifth laminate 64 in which the graphite film (A1) 22 is directly laminated on the substrate (C′) 45 . Also, depending on the constituent elements of the substrate (C') 45, when the first laminate 60 or the second laminate 61 is processed at the graphitization temperature (graphitization steps: S26, S27), the frame-containing portion may not be formed. Element, carbon film (B2) 35 is formed to form graphite film (A1) 22, and the above-mentioned fifth laminated body 64 can be produced. The pellicle composite 5 can be manufactured by performing the same etching as in the above-mentioned step S13 on the fifth laminate 64 thus obtained (etching step: S28 ).

4. Etching As the etching method, a known etching method can be appropriately selected according to the material constituting the substrate (C′) 45 . For example, when the substrate (C') 45 is molybdenum, etc., a 25 wt% nitric acid aqueous solution can be used as an etchant. In other substrates (C'), etching can also be performed using an appropriate known etchant regardless of acid or alkali. In addition, a dry etching process such as RIE (Reactive Ion Etching) may also be used.

This case is based on claiming the benefit of priority based on Japanese Patent Application No. 2018-129343 filed on July 6, 2018. The entire contents of the specification of Japanese Patent Application No. 2018-129343 filed on July 6, 2018 are incorporated herein by reference. [Example]

Hereinafter, the present invention is described in more detail by enumerating the examples, but the present invention is certainly not limited by the following examples, and of course it can also be appropriately modified and implemented within the scope of meeting the above and the following gist, all of which are included in within the technical scope of the present invention. In addition, various evaluations in the Examples were performed as follows.

1. Thickness of protective film (carbon film (A), film part (B)) The thickness of the pellicle was measured using a gradient meter (manufactured by Bruker Veeco: Dektak 150). Attach a film cut to a size of 1 cm×1 cm on a smooth glass substrate, measure the step difference between the four sides of the film and the glass substrate, and set the average value as the thickness of the protective film.

2. The carbon film (A) 20 (in the embodiment is the carbonaceous film (A1) 21 or the graphite film (A1) 22) that constitutes the protective film, the film (B2) 35 (B2) 35 (B2) that contains the frame portion element, carbon (in the embodiment The thicknesses of the molybdenum carbide film in the center) and the homogeneous film (B1) 31 (the molybdenum film in the examples) were measured using cross-sectional TEM and mapping of element distribution.

3. EUV transmittance of protective film (T) The EUV transmittance (T) of the protective film is specified as the EUV transmittance relative to the wavelength of 13.5 nm, and according to (a) carbon film (A) 20 (in the embodiment, carbon film (A1) 21 or graphite film EUV transmittance (Ta) of (A1) 22), (b) transmittance (Tb) of film (B2) 35 (molybdenum carbide film in the embodiment) containing frame elements and carbon, (c) homogeneous film (B1) Calculated by multiplying the transmittance (Tc) of 31 (molybdenum film in the example).

(1) (a1) EUV transmittance (Ta) of graphite film (A1) 22 In carbon film (A) 20, (a1) EUV transmittance (Ta=T _G [%]) of graphite film (A1) 22 is The value of the film thickness D _G (nm) of the graphite film (A1) 22 was substituted into the following formula (1), and it calculated|required. In the formula, 0.998 refers to the transmittance of one graphite layer (single-layer graphene) forming the film, and 0.3354 refers to the thickness (nm) of the one-layer graphite layer (single-layer graphene). Formula: Thickness D _G (nm)=Log _0.998 (T _G [%]/100)×0.3354 (1)

(2) The EUV transmittance (Ta) of the carbonaceous film (A1) 21 The EUV transmittance is defined by the amount of carbon that actually exists in the light path through which EUV passes, and the amount of carbon can be estimated by density. Therefore, the EUV transmittance (T _C [%]) of the carbonaceous film (A1) 21 takes into account the transmittance T _G [%] of the graphite film (A1) 22, the density of the graphite film (A1) 22 (2.24 g/cm ³ ) The density of the carbonaceous film (A1) (assumed to be 2.0 g/cm ³ ) was obtained by the following formula. The T _G of formula (2) adopts the following T _G value, and this T _G value is to measure the thickness of the carbonaceous film (A1) 21, and this carbonaceous film (A1) 21 is assumed to be the graphite film (A1) of the same thickness, and It can be obtained by applying the above formula (1). Ta(%)=T _C (%)=T _G (%)×2.24/2.0 (2)

(b) EUV transmittance (Tb) of molybdenum carbide film (B2) 35 EUV transmittance (Tb [%]) is to substitute the value of film thickness Db (nm) of molybdenum carbide film (B2) 35 into It can be calculated|required by following formula (3). In the formula, 0.993 refers to the EUV transmittance per 1 nm of the molybdenum carbide film (B2) (%/nm). Film thickness Db(nm)=Log _0.993 (Tb[%]/100) (3)

(c) EUV transmittance (Tc) of the molybdenum film (B1) The EUV transmittance (Tc[%]) of the molybdenum film (B1) 31 is substituted into the value of the film thickness Dc (nm) of the molybdenum film (B1) 31 It can be calculated|required by following formula (4). In the formula, 0.994 refers to the EUV transmittance per 1 nm of the molybdenum film (B1) (%/nm). Film thickness Dc(nm)=Log _0.994 (Tc[%]/100) (4)

4. Surface roughness The carbon film (A) 20 (in the embodiment is carbonaceous film (A1) 21 or graphite film (A1) 22) that constitutes protective film, the film (B2) 35 (B2) 35 that contains frame portion element, carbon (in the embodiment is Molybdenum carbide film), the surface roughness (Sa) of the homogeneous film (B1) 31 (molybdenum film in the embodiment) was measured using a laser microscope, and calculated based on ISO 25178. Set the magnification of the laser microscope: 50 times, the critical value (λc): 80 μm. The measurement position of the surface roughness (Sa) is to measure a plurality of positions including 1 center part and 4 end parts, and set the average value as the surface roughness (Sa).

5. D/G band intensity ratio The Raman spectrum of the carbon film (A) 20 was measured using a laser Raman microscope. The measurement position includes multiple positions at the center and 4 ends, and the intensity (I(G)) of the G band caused by the graphite structure around 1575 to 1600 cm ^-1 is obtained at each place, and the intensity (I(G)) and 1350 to 1360 The intensity (I(D)) of the D-band caused by the amorphous carbon structure around cm ^-1 , and its ratio (I(D)/I(G)), and the ratio (I(D)/I( The average value of G)) was set as the D/G band intensity ratio of the carbon film (A).

6. Hydrogen free radical resistance The resistance to hydrogen free radicals is based on the PC-300 dry cleaner manufactured by Samco, according to (A) protective film (carbon film (A) 20, frame elements, carbon film (B2) 35, homogeneous film (B1) The total of 31) was evaluated for film thickness reduction. In addition to the carbon film (A) 20, when the protective film also has non-carbon films such as the film (B2) 35 containing frame elements and carbon, and the homogeneous film (B1) 31, the carbon film (A) 20 side faces The following method is configured on a test bench with a ground electrode. When the protective film is only the carbon film (A) 20 (the case without the above-mentioned non-carbon film), the carbon film (A) 20 is arranged on the above-mentioned test stand. A power supply electrode connected with a DC blocking capacitor and an RF (Radio Frequency, radio frequency) power supply is arranged on the upper part of the platform. Under the following conditions, the protective film was exposed to hydrogen radicals from above, and the film thickness reduction of the metal carbide film was measured. B2) 35 or homogeneous film (B1) 31; in the case of the comparative example where the protective film is only composed of carbon film (A), it is the reduction in film thickness of the carbon film (A)), and is set as the film thickness of the protective film reduce the amount. [Hydrogen radical exposure conditions] Power output during test: 100 W Process Gas Flow: 100 sccm Gas pressure: 10Pa Processing time: 30 minutes

Production Example 1-1: Fabrication of Molybdenum Substrate (C') (ie, First Laminated Body 60) Equipped with Polyimide Film (A') 50 (Refer to FIG. 2 ) Synthesis of 4.0% by mass of polyamic acid obtained by mixing pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, and p-phenylenediamine at a molar ratio of 2:1:1 Methylformamide solution was coated on a 5 cm square molybdenum substrate (C') 45 (thickness 100 μm) using a spin coater. The substrate (C') was heated at 125°C, 250°C, and 450°C for 60 seconds each to produce a molybdenum substrate (C') (first laminate 60) provided with a polyimide film (A') 50 . Furthermore, the thickness of the polyimide film (A') on the substrate (C') is 80 nm.

Production Example 2-1: Fabrication of Molybdenum Substrate (C') (ie, Second Laminated Body 61) Equipped with Carbonaceous Film (A1) 21 (Refer to FIG. 2 ) The molybdenum substrate (C') (the first laminate 60) provided with the polyimide film (A') 50 of Production Example 1-1 was heated up to 900°C at a rate of 10°C/min under a nitrogen atmosphere, and kept After 15 minutes, it was left to cool naturally (step S11), and the molybdenum substrate (C') (2nd laminated body 61) provided with the carbonaceous film (A1) 21 was produced. Furthermore, the thickness of the carbonaceous film (A1) 21 on the substrate (C') is 60 nm.

Production Example 2-2: Fabrication of a molybdenum substrate (C') (that is, a third laminate 62) having a carbonaceous film (A1) 21 and a molybdenum carbide film (B2) 35 (see FIG. 2 ) The molybdenum substrate (C') (first laminate 60) with the polyimide film (A') 50 of Production Example 1-1 was heated up to 1100°C at a rate of 10°C/min under a nitrogen atmosphere, and kept Let it cool naturally after 15 minutes (step S12), and the molybdenum substrate (C') (3rd laminated body 62) provided with the carbonaceous film (A1) 21 and the molybdenum carbide film (B2) 35 was produced. Furthermore, the carbonaceous film (A1) 21 on the substrate (C') has a thickness of 47 nm, and the molybdenum carbide film (B2) 35 has a thickness of 7 nm.

Production Example 2-3: Fabrication of a molybdenum substrate (C') (that is, the fourth laminate 63) having a graphite film (A1) 22 and a molybdenum carbide film (B2) 35 (see FIG. 3 ) The molybdenum substrate (C') (third laminate 62) provided with the carbonaceous film (A1) 21 and the molybdenum carbide film (B2) 35 of Production Example 2-2 was placed under an argon atmosphere at a rate of 5°C/min. Raise the temperature to 2800° C., keep it for 20 minutes, and let it cool naturally (step S21 ), and make a molybdenum substrate (C′) (fourth laminate 63 ) with graphite film (A1) 22 and molybdenum carbide film (B2) 35 . Furthermore, the thickness of the graphite film (A1) 22 on the substrate (C′) is 13 nm, and the thickness of the molybdenum carbide film (B2) 35 is 12 nm.

Manufacturing Example 3-1: Fabrication of a coating complex 2 with a carbonaceous film (A1) 21 and a molybdenum film (B1) 31 (see FIG. 2 ) After protecting the 4 sides of the substrate (C') side of the molybdenum substrate (C') (second laminate 61) with the carbonaceous film (A1) 21 in Production Example 2-1 with a water-resistant adhesive tape with a width of 10 mm , immersed in 25 wt% nitric acid at a liquid temperature of 20°C for 50 minutes, and wet-etched the substrate (C') with a part remaining as the frame (C) (step S13), and produced a 3 cm square carbon Sheath complex 2 of plasma membrane (A1)21 and molybdenum membrane (B1)31.

Manufacturing Example 3-2: Fabrication of a protective film composite 4 with a carbonaceous film (A1) 21 and a molybdenum carbide film (B2) 35 (see FIG. 2 ) In Manufacturing Example 3-1, the molybdenum substrate (C') (third laminate 62) provided with the carbonaceous film (A1) 21 and the molybdenum carbide film (B2) 35 of Manufacturing Example 2-2 was used instead of Manufacturing Example 2- 1 molybdenum substrate (C') (second laminated body 61), and the film composite body 4 having the carbonaceous film (A1) 21 and the molybdenum carbide film (B2) 35 is produced.

Manufacturing Example 3-3: Fabrication of a coating composite 3 with a carbonaceous film (A1) 21, a molybdenum carbide film (B2) 35 and a molybdenum film (B1) 31 The substrate (C') of the molybdenum substrate (C') (third laminated body 62) having the carbonaceous film (A1) 21 and the molybdenum carbide film (B2) 35 of Production Example 2-2 was made using a water-resistant adhesive tape with a width of 10 mm ) after protecting the 4 sides on the side, dip in 25 wt% nitric acid at a liquid temperature of 20°C for 45 minutes, and wet-etch the substrate (C') in such a way that a part remains as the frame (C), and make a 3 cm Square protective film complex 3 with carbonaceous film (A1) 21, molybdenum carbide film (B2) 35 and molybdenum film (B1) 31.

Manufacturing Example 3-4: Fabrication of a coating composite 7 with a graphite film (A1) 22 and a molybdenum carbide film (B2) 35 (refer to FIG. 3 ) On the 4 sides of the substrate side of the molybdenum substrate (C') (fourth laminate 63) with the graphite film (A1) 22 and the molybdenum carbide film (B2) 35 in Manufacturing Example 2-3 using a water-resistant adhesive tape with a width of 10 mm After protection, dip in 25 wt% nitric acid at a liquid temperature of 20°C for 50 minutes, and wet-etch the substrate (C') in such a way that a part remains as the frame (C), and make a 3 cm square graphite film (A1) 22 and molybdenum carbide film (B2) 35 coating complex 7.

Manufacturing Example 3-5: Fabrication of a protective film composite 6 with graphite film (A1) 22, molybdenum carbide film (B2) 35 and molybdenum film (B1) 31 The immersion time in 25 wt% nitric acid was changed from 50 minutes to 45 minutes. In addition, a graphite film (A1) 22, a molybdenum carbide film (B2) 35 and a molybdenum Membrane complex 6 of membrane (B1) 31.

Example 1 For the protective film composite 2 with the carbonaceous film (A1) 21 and the molybdenum film (B1) 31 in Production Example 3-1, evaluate the thickness and surface roughness of each film, and the Raman spectrum of the carbonaceous film (A1) 21 Peak intensity ratio, hydrogen free radical resistance of coating complex 2. The EUV transmittance of the pellicle is calculated based on the theoretical value of the EUV transmittance of each film. The results are shown in Table 1.

Example 2~5 Except for using the pellicle complexes 3, 4, 6, and 7 disclosed in Production Examples 3-2 to 3-5, it was the same as Example 1. The results are shown in Table 1.

Comparative example 1 A carbonaceous film (A1) 21 was produced in the same manner as in Production Example 2-1 except that the substrate (C') was not used. The obtained carbonaceous film (A1) 21 was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative example 2 Graphite film (A1) 22 was produced in the same manner as in Production Example 2-3 except that the substrate (C') was not used. The obtained graphite film (A1) 22 was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[產業上之可利用性][Table 1] Table 1

[Industrial availability]

The pellicle complex of the present invention is useful for protecting the photomask used in various lithography methods such as EUV lithography.

1‧‧‧Membrane Complex 2‧‧‧Membrane Complex 3‧‧‧Membrane complex 4‧‧‧Membrane complex 5‧‧‧Membrane complex 6‧‧‧Membrane complex 7‧‧‧Membrane complex 20‧‧‧Carbon film (A) 21‧‧‧Carbon film (A1) 22‧‧‧Graphite film (A1) 25‧‧‧Protective film 30‧‧‧Membrane (B) 31‧‧‧Homogeneous Membrane (B1) 35‧‧‧Film containing frame elements and carbon (B2) 40‧‧‧Frame (C) 45‧‧‧Substrate (C') 50‧‧‧Carbonized raw film (A') 60‧‧‧1st laminate 61‧‧‧The second laminated body 62‧‧‧The third laminated body 63‧‧‧4th laminate 70‧‧‧adhesive 80‧‧‧Reticle S11‧‧‧Carbonization step S12‧‧‧Carbonization step S13‧‧‧etching step S14‧‧‧etching step S15‧‧‧etching step S16‧‧‧Carbonization step S17‧‧‧Carbonization step S21‧‧‧Graphitization step S22‧‧‧Graphitization step S23‧‧‧Graphitization step S24‧‧‧etching step S25‧‧‧etching step S26‧‧‧Graphitization step S27‧‧‧Graphitization step S28‧‧‧etching step

1 (a) to (f) are schematic cross-sectional views showing examples of the pellicle complex of the present invention. Fig. 2 is a schematic flow chart showing an example of the manufacturing method of the pellicle complex of the present invention. Fig. 3 is a schematic flow chart showing another example of the manufacturing method of the pellicle complex of the present invention. Fig. 4 is a schematic cross-sectional view showing a photomask provided with a conventional pellicle complex.

1‧‧‧Membrane Complex

2‧‧‧Membrane Complex

3‧‧‧Membrane complex

4‧‧‧Membrane complex

5‧‧‧Membrane complex

6‧‧‧Membrane complex

7‧‧‧Membrane complex

20‧‧‧Carbon film (A)

21‧‧‧Carbon film (A1)

22‧‧‧Graphite film (A1)

30‧‧‧Membrane (B)

31‧‧‧Homogeneous Membrane (B1)

35‧‧‧Film containing frame elements and carbon (B2)

40‧‧‧Frame (C)

Claims (10)

A protective film composite, characterized in that it has: a carbon film (A), a film part (B) surface-bonded to one side of the carbon film, and a frame part ( C) The element constituting the above-mentioned frame part (C) is one or more kinds selected from the group consisting of zirconium, niobium, molybdenum, titanium, and tungsten, and is used as a constituent element in the above-mentioned film part (B) at least partially contained. The protective film composite as claimed in claim 1, wherein the above-mentioned film part (B) satisfies being a layer of the same material as the frame part (C), or at least one of the layers containing both elements and carbon constituting the frame part (C) one. The coating composite according to claim 1 or 2, wherein the carbon film (A) is directly bonded to the film part (B). The protective film composite according to claim 1 or 2, wherein the carbon film (A) is a carbon film or a graphite film (A1). The coating composite according to claim 1 or 2, wherein the surface roughness of the carbon film (A) and/or the film part (B) is not less than 0.1 nm and not more than 500 nm. A method of manufacturing a protective film composite as claimed in any one of claims 1 to 5, wherein a carbonized raw material film (A' is layered on a single layer of a substrate (C') made of the same material as the frame portion (C) above ) laminated body is heated to make the above-mentioned carbonized raw material film (A') into a carbon film (A), and then etched from the substrate (C') side In the laminated body, the outer edge of the substrate (C') is left thicker than the other parts to form the frame part (C), and on the other hand, the film part ( B). A method of manufacturing a protective film composite as claimed in any one of claims 1 to 5, wherein a carbonized raw material film (A' is layered on a single layer of a substrate (C') made of the same material as the frame portion (C) above ) laminated body is heated, so that the above-mentioned carbonized raw material film (A') becomes a carbonaceous film or a graphite film (A1) and a layer (B2) containing both elements and carbon constituting the frame part (C) Two layers, The above-mentioned carbon film (A) and the above-mentioned film part (B) are formed, and then the outer edge of the substrate (C') is left as the above-mentioned frame part (C), and the above-mentioned laminate is etched from the substrate (C') side. The method of manufacturing a pellicle composite according to Claim 7, wherein the substrate other than the remaining portion of the frame portion (C) is etched while remaining, and the remaining portion and the above-mentioned layer (B2) are set as the above-mentioned Membrane part (B). The method of manufacturing a pellicle composite according to claim 7, wherein the substrate (C') other than the remaining portion of the frame portion (C) is completely removed by the etching. The method for producing a protective film composite according to any one of claims 6 to 9, wherein the above-mentioned carbonized raw material film (A') is an aromatic polyimide film.

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