Blank mask and its manufacturing method

Abstract

To provide a device for fabricating a blank mask and a method of fabricating the blank mask, the blank mask being capable of providing a photomask having low defect occurrence, an improved number of uses, and high precision.SOLUTION: A method of fabricating a blank mask includes forming a light-shielding film on a light-transmissive substrate to form an optical substrate; forming a photoresist layer on the light-shielding film; and removing droplets, generated in forming the photoresist layer, from a side surface of the light-transmissive substrate, where the number of droplet-type adsorption, derived from the droplets, on the side surface of the light-transmissive substrate is less than 3 pieces / cm2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The embodiments relate to a blank mask and a method for manufacturing the blank mask. [Background technology]

[0002] The increasing integration of semiconductor devices and other devices requires finer circuit patterns, which further emphasizes the importance of lithography, a technology for developing circuit patterns on the surface of a wafer using a photomask.

[0003] In order to develop fine circuit patterns, the exposure light source used in the exposure process must have a shorter wavelength. In recent years, the exposure light source used is the ArF excimer laser (wavelength 193 nm).

[0004] Meanwhile, photomasks include binary masks and phase shift masks.

[0005] A binary mask has a configuration in which a light-shielding layer pattern is formed on a light-transmitting substrate. In the binary mask, on the surface on which the pattern is formed, a transparent portion not including a light-shielding layer transmits the exposure light, and a light-shielding portion including a light-shielding layer blocks the exposure light, thereby exposing the pattern on a resist film on the surface of the wafer. However, as the pattern becomes finer, a binary mask may cause problems in developing fine patterns due to diffraction of light occurring at the edge of the transparent portion during the exposure process.

[0006] Phase shift masks include Levenson type, outrigger type, and half-tone type. Among them, the half-tone type phase shift mask has a structure in which a pattern formed of a semi-transmitting film is formed on a light-transmitting substrate 20. In the half-tone type phase shift mask, on the surface on which the pattern is formed, the transmissive portion not including the semi-transmitting layer transmits the exposure light, and the semi-transmitting portion including the semi-transmitting layer transmits the attenuated exposure light. The attenuated exposure light has a phase difference compared to the exposure light that has passed through the transmissive portion. As a result, the diffracted light generated at the edge of the transmissive portion is offset by the exposure light that has passed through the semi-transmitting portion, and the phase shift mask can form a more elaborate and fine pattern on the surface of the wafer. [Prior art documents] [Patent documents]

[0007] The relevant prior art documents are as follows: [Patent Document 1] Korean Patent Publication No. 10-2012-0057488 [Patent Document 2] Korean Patent Publication No. 10-2014-0130420 Summary of the Invention [Problem to be solved by the invention]

[0008] The embodiments are intended to provide an apparatus for manufacturing a blank mask and a method for manufacturing a blank mask, which can provide a photomask having fewer defects, improved number of uses, and high precision. [Means for solving the problem]

[0009] A method for manufacturing a blank mask according to an embodiment includes the steps of forming an optical substrate by forming a light-shielding film on a light-transmitting substrate, forming a photoresist layer on the light-shielding film, and removing droplets generated in the step of forming the photoresist layer from a side surface of the light-transmitting substrate, and the droplets adsorbed on the side surface of the light-transmitting substrate are less than 3 droplets / cm. 2 is less than.

[0010] According to one embodiment, the method for manufacturing a blank mask further includes a step of mounting the optical substrate on a chuck, and the step of forming the photoresist layer includes a step of dropping a photoresist composition on the light-shielding film, a step of rotating the optical substrate, and a step of injecting compressed air between the optical substrate and the chuck, and the steps of rotating the optical substrate and spraying compressed air can be performed simultaneously.

[0011] According to one embodiment, the method for manufacturing a blank mask further includes a step of mounting the optical substrate on a chuck, and the step of forming the photoresist layer includes a step of dropping a photoresist composition on the light-shielding film, a step of rotating the optical substrate, and a step of applying a vacuum pressure between a side of the optical substrate and the chuck, and the steps of rotating the optical substrate and applying the vacuum pressure can be performed simultaneously.

[0012] In one embodiment of the method for manufacturing a blank mask, the droplet adsorption rate on the lower surface of the light-transmitting substrate is 4 droplets / cm 2 It may be less than.

[0013] In one embodiment of a method for manufacturing a blank mask, the chuck may include a support portion for supporting the optical substrate and a guide portion arranged on a side of the optical substrate, and in the step of rotating the optical substrate, the optical substrate and the guide portion may be rotated simultaneously, and the compressed air may be injected between the guide portion and the side of the optical substrate.

[0014] In one embodiment of a method for manufacturing a blank mask, the chuck includes a support portion that supports the optical substrate and a guide portion that is arranged on a side of the optical substrate, and in the step of rotating the optical substrate, the optical substrate and the guide portion may be rotated simultaneously, and the vacuum pressure may be applied between the guide portion and the side of the optical substrate.

[0015] In the manufacturing method of the blank mask according to one embodiment, the optical substrate may include the droplet-like suctions, the droplet-like suctions may have an island shape, and a diameter of the droplet-like suctions may be about 0.01 μm to about 10 μm.

[0016] In one embodiment of the method for manufacturing a blank mask, the droplet adsorption on the side surface of the light-transmitting substrate is about 0.05 droplets / cm 2 ~About 1 piece / cm 2 may be also possible.

[0017] The blank mask according to the embodiment includes a light-transmitting substrate, a light-shielding film disposed on the light-transmitting substrate, and a photoresist layer disposed on the light-shielding film and containing a photosensitive resin. The droplet-like adhesion rate of the photosensitive resin on the side surface of the light-transmitting substrate is 3 droplets / cm. 2 is less than.

[0018] In one embodiment of the blank mask, the droplets adsorbed on the lower surface of the light-transmitting substrate are 4 droplets / cm 2 It may be less than.

[0019] In one embodiment of the blank mask, the droplets adsorbed on the side surface of the light-transmitting substrate are 2.5 droplets / cm 2 It may be less than.

[0020] In one embodiment of the blank mask, the droplets adsorbed on the side surface of the light-transmitting substrate are 0.5 droplets / cm 2 It may be less than.

[0021] In one embodiment of the blank mask, the droplets adsorbed on the lower surface of the light-transmitting substrate are 2 droplets / cm 2 It may be less than.

[0022] In the blank mask according to one embodiment, the droplets of adsorption may have a diameter of 0.01 μm to 10 μm.

[0023] A blank mask according to an embodiment includes a light-transmitting substrate, a light-shielding film disposed on the light-transmitting substrate, a photoresist layer disposed on the light-shielding film and containing a photosensitive resin, and droplet-like adsorptions containing the photosensitive resin and having island shapes on a side surface of the light-transmitting substrate, the density of the droplet-like adsorptions on the side surface of the light-transmitting substrate being about 0.05 pieces / cm 2 ~About 3 pieces / cm 2 It is.

[0024] In one embodiment of the blank mask, the droplets are arranged on the lower surface of the light-transmitting substrate, and the density of the droplets on the lower surface of the light-transmitting substrate is about 0.05 droplets / cm 2 ~About 3 pieces / cm 2 may be also possible.

[0025] In one embodiment of the blank mask, the droplet-shaped particles include first droplets having a diameter of about 0.01 μm or more and less than about 0.04 μm, and the number of the first droplets is about 0.05 particles / cm. 2 ~about 0.5 pieces / cm 2 may be also possible.

[0026] In one embodiment of the blank mask, the droplet-shaped adhesion includes second droplet-shaped adhesion having a diameter of about 0.04 μm or more and less than about 0.3 μm, and the number of the second droplet-shaped adhesion is about 0.05 pieces / cm 2 ~about 0.5 pieces / cm 2 may be also possible.

[0027] In one embodiment of the blank mask, the droplet-shaped adsorption includes a third droplet-shaped adsorption having a diameter of about 0.3 μm or more and less than about 3 μm, and the number of the third droplet-shaped adsorption is about 0.05 pieces / cm 2 ~about 0.5 pieces / cm 2 may be also possible.

[0028] In one embodiment of the blank mask, the droplet-shaped adsorption includes a fourth droplet-shaped adsorption having a diameter of about 3 μm or more and less than about 10 μm, and the number of the fourth droplet-shaped adsorption is about 0.05 pieces / cm 2 ~about 0.5 pieces / cm 2 may be also possible.

[0029] In one embodiment of the blank mask, the density of the droplets on the side surface of the light-transmitting substrate is about 0.05 droplets / cm 2 ~About 1 piece / cm 2 may be also possible. Effect of the Invention

[0030] The method for manufacturing a blank mask according to the embodiment includes removing splashes generated during the step of forming the photoresist layer, thereby preventing the side and / or bottom surface of the light-transmitting substrate from being contaminated by process by-products such as splashes.

[0031] In particular, in the method for manufacturing a blank mask according to the embodiment, compressed air or vacuum pressure can be used to remove droplets scattered from a photoresist composition for forming the photoresist layer from the side surface of the light-transmitting substrate.

[0032] As a result, the blank mask manufacturing method according to the embodiment can effectively prevent the droplets from being adsorbed on the side and bottom surfaces of the light-transmitting substrate.

[0033] As a result, in the method for manufacturing a blank mask according to the embodiment, the droplet adsorption on the side surface of the light-transmitting substrate is 3 droplets / cm 2In addition, in the method for producing a blank mask according to the embodiment, it is possible to provide a blank mask in which the droplet adsorption rate on the lower surface of the light-transmitting substrate is less than 4 droplets / cm. 2 A blank mask can be provided that is less than

[0034] As a result, the blank mask manufacturing method according to the embodiment may minimize optical distortion caused by droplet adsorption, and thus the blank mask manufacturing method according to the embodiment may have improved optical performance.

[0035] Furthermore, since the blank mask manufacturing method according to the embodiment suppresses droplet adsorption as described above, no additional process is required to remove droplets adsorbed to the side and bottom surfaces of the light-transmitting substrate.

[0036] Therefore, the method for manufacturing a blank mask according to the embodiment can prevent the photoresist layer from being damaged by an additional process for removing the droplet-like adhesion.

[0037] In the blank mask according to the embodiment, the droplets adsorbed on the side and bottom surfaces of the light-transmitting substrate are 4 droplets / cm 2 Since the optical distortion can be minimized, the optical performance can be improved. [Brief description of the drawings]

[0038] [Figure 1] FIG. 2 is a schematic diagram showing a blank mask manufacturing apparatus according to an embodiment. [Diagram 2] FIG. 1 is a perspective view showing a chuck according to an embodiment. [Diagram 3] FIG. 2 illustrates a top view of a chuck according to one embodiment. [Figure 4] FIG. 2 is a cross-sectional view showing one section of the chuck. [Diagram 5] 5 is an enlarged cross-sectional view of part A in FIG. 4. [Figure 6]FIG. 2 illustrates a process for removing process by-products in one embodiment. [Figure 7] FIG. 13 is a diagram showing a process for removing process by-products in another embodiment. [Figure 8] FIG. 13 is a schematic diagram showing a blank mask manufacturing apparatus according to still another embodiment. [Figure 9] FIG. 13 is a diagram showing a process for removing process by-products in yet another embodiment. [Figure 10] 2 is a cross-sectional view showing a cross section of an optical substrate according to an embodiment. [Figure 11] 11 is a cross-sectional view showing a cross section of an optical substrate according to another embodiment. [Figure 12] 11 is a cross-sectional view showing a cross section of an optical substrate according to still another embodiment. [Figure 13] 1 is a cross-sectional view showing one cross section of a blank mask according to an embodiment. [Figure 14] 1 is a cross-sectional view showing one cross section of a photomask according to an embodiment; [Figure 15] FIG. 2 is a diagram showing a part of a side surface of a light-transmitting substrate according to an embodiment. [Figure 16] 16 is a cross-sectional view showing a cross section cut along the line BB' in FIG. 15. [Figure 17] 4 is a cross-sectional view showing a portion of a lower surface of a light-transmitting substrate according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a method for manufacturing a semiconductor device according to an embodiment of the present invention;

[0040] As used herein, terms of degree such as "about," "substantially," and the like are used to mean a numerical value or close to a numerical value when the tolerances of manufacturing and materials inherent in the referred meaning are given, and are used to prevent unconscionable infringers from unfairly exploiting the contents of the disclosure in which precise or absolute numerical values ​​are referred to for the understanding of the embodiments.

[0041] Throughout this specification, the term "combinations thereof" contained in a Markush form phrase is intended to mean a mixture or combination of one or more selected from the group of elements set forth in the Markush form phrase, including one or more selected from the group of elements.

[0042] Throughout this specification, the phrase "A and / or B" means "A, B, or A and B."

[0043] Throughout this specification, terms such as "first", "second" or "A", "B" are used to distinguish between similar terms, unless otherwise specified.

[0044] In this specification, the term "B is located on A" means that B is located on A, or B is located on A with another layer therebetween, or B may be located thereon, and is not to be interpreted as being limited to B being located in contact with the surface of A.

[0045] In this specification, the singular expression is to be construed as including the singular or plural as the context requires, unless otherwise specified.

[0046] FIG. 1 is a schematic diagram showing a manufacturing apparatus for a blank mask according to an embodiment. FIG. 2 is a perspective view showing a chuck according to an embodiment. FIG. 3 is a view showing an upper surface of a chuck according to an embodiment. FIG. 4 is a cross-sectional view showing one cross section of the chuck. FIG. 5 is a cross-sectional view showing an enlarged view of part A in FIG. 4. FIG. 6 is a view showing a process of removing a process by-product in one embodiment. FIG. 7 is a view showing a process of removing a process by-product in another embodiment. FIG. 8 is a schematic diagram showing a manufacturing apparatus for a blank mask according to yet another embodiment. FIG. 9 is a view showing a process of removing a process by-product in yet another embodiment. FIG. 10 is a cross-sectional view showing one cross section of an optical substrate according to an embodiment. FIG. 11 is a cross-sectional view showing one cross section of an optical substrate according to another embodiment. FIG. 12 is a cross-sectional view showing one cross section of an optical substrate according to yet another embodiment. FIG. 13 is a cross-sectional view showing one cross section of a blank mask according to an embodiment. FIG. 14 is a cross-sectional view showing one cross section of a photomask according to an embodiment. FIG. 15 is a view showing a part of a side surface of a light-transmitting substrate according to an embodiment. Fig. 16 is a cross-sectional view showing a cross section cut along the line BB' in Fig. 15. Fig. 17 is a cross-sectional view showing a part of the lower surface of a light-transmitting substrate according to an embodiment.

[0047] Referring to FIG. 1, the manufacturing apparatus for a blank mask according to the embodiment includes a chamber 100, a chuck 200, a first air pump 300, an exhaust unit 400, a photoresist resin composition supply unit 500, an air sweep unit 610, a second air pump 600, and a spindle motor 700.

[0048] The chamber 100 accommodates the chuck 200. The chamber 100 can accommodate an optical substrate 10 for manufacturing a blank mask. The chamber 100 can have an interior isolated from the outside. The interior of the chamber 100 can be sealed. The internal pressure of the chamber 100 can be a vacuum lower than atmospheric pressure.

[0049] The chamber 100 may include a door or a lid that can be opened and closed. The chamber 100 may include a heater or the like that can adjust the internal temperature of the chamber 100.

[0050] 2 to 7, the chuck 200 includes a support portion 210, a guide portion 220, and a by-product removal portion 230. The support portion 210 is a support member.

[0051] The supporting portion 210 can support the guide portion 220 and the by-product removal portion 230. The supporting portion 210 supports the optical substrate 10. The supporting portion 210 may be disposed below the optical substrate 10.

[0052] The supporting part 210 can temporarily fix the optical substrate 10. The supporting part 210 can temporarily fix the optical substrate 10 by vacuum pressure or electrostatic force.

[0053] The guide portion 220 may be connected to the support portion 210. The guide portion 220 may be formed integrally with the support portion 210. The guide portion 220 may be disposed on a side surface 12 of the optical substrate 10. The guide portion 220 may surround the side surface 12 of the optical substrate 10.

[0054] The support portion 210 and the guide portion 220 can form a receiving portion 240 that receives the optical substrate 10. That is, the support portion 210 may be disposed on the lower surface 13 of the optical substrate 10, and the guide portion 220 may be disposed on the side surface 12 of the optical substrate 10, thereby forming the receiving portion 240.

[0055] The receiving portion 240 may correspond to a planar shape of the optical substrate 10. The planar shape of the receiving portion 240 may be substantially similar to the planar shape of the optical substrate 10. The planar shape of the optical substrate 10 may be a square, and the planar shape of the receiving portion 240 may also be a square.

[0056] The outer periphery of the guide portion 220 may have a circular shape. The guide portion 220 and the support portion 210 may have a circular shape.

[0057] The by-product removal portion 230 may be formed in the support portion 210. The by-product removal portion 230 may be formed in the guide portion 220. The by-product removal portion 230 may be formed at a portion where the support portion 210 and the guide portion 220 intersect. The by-product removal portion 230 may be formed across the support portion 210 and the guide portion 220.

[0058] The by-product removal portion 230 may be formed in a region corresponding to an edge portion of the optical substrate 10. The by-product removal portion 230 may be formed along an edge portion of the support portion 210.

[0059] The by-product removal section 230 may include a number of holes for injecting gas. The holes may extend upward. The diameter of the holes may be about 0.5 mm to about 2 mm. The distance between the holes may be about 10 mm to 100 mm.

[0060] The by-product removal portion 230 may be disposed under a space 250 between the guide portion 220 and the side surface 12 of the optical substrate 10. The by-product removal portion 230 may be disposed in correspondence with a region 250 between an inner surface of the guide portion 220 and the side surface 12 of the optical substrate 10.

[0061] The guide portion 220 and the side surface 12 of the optical substrate 10 may be spaced apart at a constant interval. The distance (D) between the inner surface of the guide portion 220 and the side surface 12 of the optical substrate 10 may be about 0.01 mm to about 1 mm. The distance (D) between the guide portion 220 and the side surface 12 of the optical substrate 10 may be less than about 1 mm.

[0062] Since the guide portion 220 and the side surface 12 of the optical substrate 10 have the above-mentioned distance (D), the inflow of the process by-products 511 into the space 250 between the guide portion 220 and the optical substrate 10 can be suppressed.

[0063] In addition, since the holes have the diameter and interval within the above range, the by-product removal unit 230 can easily inject compressed air or apply vacuum pressure to the space between the guide unit 220 and the optical substrate 10. Thus, since the holes have the diameter and interval within the above range, the by-product removal unit 230 can easily remove the process by-products 511 that flow into the space 250 between the guide unit 220 and the optical substrate 10.

[0064] The height difference (H) between the upper surface 221 of the guide part 220 and the upper surface 11 of the optical substrate 10 may be less than about 1 mm. The height difference (H) between the upper surface 221 of the guide part 220 and the upper surface 11 of the optical substrate 10 may be about 0.1 mm to about 1 mm. The upper surface 221 of the guide part 220 may be lower than the upper surface 11 of the optical substrate 10.

[0065] When the height difference (H) between the upper surface 221 of the guide portion 220 and the upper surface 11 of the optical substrate 10 is as described above, the process by-product 511 can be easily discharged when a photoresist resin composition is spin-coated onto the optical substrate 10.

[0066] The by-product removal unit 230 may be connected to the first air pump 300. The by-product removal unit 230 may be connected to the first air pump 300 via a flow path 260. The by-product removal unit 230 may push out the process by-products 511 by applying compressed air generated by the first air pump 300 via the flow path 260. That is, the process by-products 511 may be blown upward from the by-product removal unit 230 by the first air pump 300.

[0067] That is, the compressed air is generated from the first air pump 300 and is sprayed upward from the by-product removal unit 230 through the flow path 260. As a result, the process by-products that flow between the optical substrate 10 and the guide unit 220 can be discharged upward.

[0068] In addition, the compressed air may be continuously sprayed upward from the by-product removal unit 230. This can essentially prevent the process by-products from entering the space 250 between the side surface of the optical substrate 10 and the guide unit 220.

[0069] The process by-products 511 may include fine particles. The fine particles may be formed by scattering of the photoresist resin composition. The process by-products 511 may be droplets formed by scattering of the photoresist resin composition. That is, the fine particles may be the droplets.

[0070] The droplets may also include the photoresist resin composition. The droplets may include substantially the same material as a material for forming the photoresist layer. The droplets and the photoresist layer may have substantially the same composition.

[0071] The fine particles may have a particle size of less than about 10 μm.The fine particles may have a particle size of about 1 μm to about 10 μm.

[0072] The spraying speed of the by-product removal unit 230 may be about 0.3 ml / s to about 100 ml / s. The spraying speed of the by-product removal unit 230 may be about 0.4 ml / s to about 20 ml / s. The spraying speed of the by-product removal unit 230 may be about 0.5 ml / s to about 10 ml / s. Thus, the by-product removal unit 230 can easily remove the process by-products 511 contained in the space 250 between the guide unit 220 and the optical substrate 10.

[0073] The first air pump 300 may be connected to the by-product removal unit 230. The first air pump 300 may be connected to the by-product removal unit 230 via the flow path. The first air pump 300 may supply the compressed air to the by-product removal unit 230.

[0074] The exhaust unit 400 can exhaust the gas inside the chamber 100. In addition, the exhaust unit 400 can exhaust the photoresist composition remaining after being coated on the optical substrate 10. The exhaust unit 400 can exhaust the photoresist resin composition scattered to the side of the chuck 200.

[0075] The photoresist resin composition supply unit 500 may supply the photoresist resin composition 510 to the upper surface of the optical substrate 10. The photoresist resin composition 510 may include a spray nozzle disposed in the chamber 100. The photoresist resin composition 510 may be dropped onto the optical substrate 10 through the spray nozzle. That is, the photoresist resin composition supply unit 500 may spray the photoresist resin composition 510 onto the upper surface of the optical substrate 10.

[0076] The chuck 200 and the optical substrate 10 may be rotated simultaneously. That is, the guide unit 220 and the optical substrate 10 may be rotated simultaneously. In addition, while the guide unit 220 and the optical substrate 10 are rotated simultaneously, the photoresist resin composition supply unit 500 may supply the photoresist resin composition 510 onto an upper surface of the optical substrate 10.

[0077] In addition, while the guide part 220 and the optical substrate 10 are rotated simultaneously, the by-product removal part 230 can remove process by-products 511 contained in the space 250 between the guide part 220 and the optical substrate 10.

[0078] 1 and 6, the air sweep portion 610 may be disposed on the optical substrate 10. The air sweep portion 610 may be disposed on the chuck 200.

[0079] The air sweep unit 610 may inject the induced air toward an outer periphery of the optical substrate 10. The air sweep unit 610 may inject the induced air from the center of the optical substrate 10 toward the outside. The air sweep unit 610 may inject the induced air toward the outer downward direction with respect to the upper surface of the optical substrate 10. That is, the air sweep unit 610 may inject the induced air toward the outside of the optical substrate 10.

[0080] Thus, process by-products ejected from the space between the side surface of the optical substrate 10 and the guide unit 220 can flow outward. That is, the air sweep unit 610 can guide the air flow ejected upward from the space 250 between the side surface of the optical substrate 10 and the guide unit 220 to the outside of the optical substrate 10.

[0081] Thus, the air sweep unit 610 can prevent the upper surface of the optical substrate 10 from being contaminated by the ejected process by-products.

[0082] The second air pump 600 may be connected to the air sweep unit 610. The second air pump 600 may supply the induced air to the air sweep unit 610.

[0083] The second air pump 600 may be omitted, and the air sweep unit 610 may be connected to the first air pump 300. The air sweep unit 610 may be supplied with the induced air from the first air pump 300.

[0084] 7, the air sweep unit 610 may include a suction nozzle 620. The suction nozzle 620 may extend from the exhaust unit 400 and be disposed on one side of the chuck 200. The suction nozzle may suck in the photoresist composition that is laterally scattered from the chuck 200.

[0085] In addition, the air sweep unit 610 can guide the flow of compressed air ejected from the space 250 between the side surface of the optical substrate 10 and the guide unit 220 to the outside of the optical substrate 10. As a result, the air sweep unit 610 can prevent the upper surface of the optical substrate 10 from being contaminated by the ejected process by-products.

[0086] The spindle motor 700 may be connected to the chuck 200. The spindle motor 700 can rotate the chuck 200 at high speed. The chuck 200 can be rotated by the spindle motor 700 at a speed of about 500 rpm to about 7000 rpm.

[0087] As the chuck 200 rotates, centrifugal force may be applied to the dropped photoresist resin composition, so that a photoresist resin composition layer may be formed on the optical substrate 10 with a uniform thickness.

[0088] The by-product removal unit 230 can push out the process by-products 511 using the compressed air. Thus, the by-product removal unit 230 can easily remove the fine particle-like process by-products 511 that flow between the guide unit 220 and the side surface 12 of the optical substrate 10. That is, while the guide unit 220 and the optical substrate 10 are simultaneously rotating, the by-product removal unit 230 can remove the fine particle-like process by-products 511 that flow between the guide unit 220 and the side surface 12 of the optical substrate 10.

[0089] In particular, since the by-product removal unit 230 is disposed in correspondence with the region between the side surface 12 of the optical substrate 10 and the guide unit 220, the process by-products 511 can be removed efficiently.

[0090] Therefore, the blank mask manufacturing apparatus according to the embodiment can minimize contamination of the process by-products 511. In particular, the blank mask according to the embodiment can prevent the process by-products 511 from contaminating the side surface 12 and the bottom surface 13 of the optical substrate 10.

[0091] 8, the blank mask manufacturing apparatus according to another embodiment may further include a vacuum unit 310. Also, the blank mask manufacturing apparatus according to another embodiment may omit the air sweep unit.

[0092] The vacuum unit 300 may be connected to the by-product removal unit 230. The vacuum unit 300 may be connected to the by-product removal unit 230 via the flow path 260. The vacuum unit 300 may apply a vacuum pressure to the by-product removal unit 230. The vacuum unit 300 may suck in and filter the process by-products 511. The vacuum unit 300 may exhaust the process by-products 511.

[0093] 9, the by-product remover 230 may suck the process by-products 511 through vacuum pressure. Thus, the by-product remover 230 may easily remove the fine particle-like process by-products 511 that flow between the guide unit 220 and the side surface 12 of the optical substrate 10.

[0094] In particular, when the by-product remover 230 is disposed in correspondence with a corner portion where the side surface 12 and the lower surface 13 of the optical substrate 10 intersect, the process by-products 511 can be removed efficiently.

[0095] Therefore, the blank mask manufacturing apparatus according to the embodiment can minimize contamination of the process by-products 511. In particular, the blank mask according to the embodiment can prevent the process by-products 511 from contaminating the side surface 12 and the bottom surface 13 of the optical substrate 10.

[0096] The by-product removal unit 230 may suck the process by-products 511 by applying the vacuum pressure generated by the vacuum unit 300 through the flow path 260. That is, the process by-products 511 may be removed by the vacuum unit 300 through the by-product removal unit 230 and the flow path 260.

[0097] In particular, while the guide unit 220 and the optical substrate 10 rotate simultaneously, the by-product removal unit 230 can suck in the process by-products 511 between the guide unit 220 and the optical substrate 10 by applying the vacuum pressure generated by the vacuum unit 300 through the flow path 260.

[0098] The exhaust speed of the by-product removal unit 230 may be about 1 ml / s to about 100 ml / s, so that the by-product removal unit 230 can easily remove the process by-products 511 contained in the space between the guide unit 220 and the optical substrate 10.

[0099] The blank mask according to the embodiment can be manufactured by the following manufacturing process.

[0100] First, an optical substrate 10 can be provided. The optical substrate 10 includes a light-transmitting substrate 20 and a light-shielding film 30 disposed on the light-transmitting substrate 20.

[0101] The light-transmitting substrate 20 may have light transmittance to the exposure light. The light-transmitting substrate 20 may have a transmittance of more than about 85% to the exposure light having a wavelength of about 193 nm. The transmittance of the light-transmitting substrate 20 may be more than about 87%. The transmittance of the light-transmitting substrate 2010 may be less than 99.99%. The light-transmitting substrate 20 may include a synthetic quartz substrate. In such a case, the light-transmitting substrate 20 can suppress attenuation of the transmitted light.

[0102] The light-transmitting substrate 20 has surface characteristics such as appropriate flatness and appropriate illuminance, and thus can suppress distortion of the transmitted light.

[0103] The light-shielding film 30 may be disposed on the top side of the light-transmitting substrate 20 .

[0104] The light-shielding film 30 can at least selectively block exposure light incident on the bottom side of the light-transmitting substrate 20 .

[0105] Also, as shown in FIG. 10, when a phase shifting film 40 or the like is disposed between the light-transmitting substrate 20 and the light-shielding film 30, the light-shielding film 30 can be used as an etching mask in a process of etching the phase shifting film 40 or the like according to a pattern shape.

[0106] The light-shielding film 30 may contain at least one of a transition metal, oxygen, and nitrogen.

[0107] The light-shielding film 30 may include chromium, oxygen, nitrogen, and carbon. The elemental contents of the entire light-shielding film 30 may be different in the thickness direction. When the light-shielding film 30 is a multi-layered film, the elemental contents of the entire light-shielding film 30 may be different for each layer.

[0108] The light-shielding film 30 may contain chromium at a content of about 44 atom % to about 60 atom %.The light-shielding film 30 may contain chromium at a content of about 47 atom % to about 57 atom %.

[0109] The light-shielding film 30 may contain carbon at a content of about 5 atom % to about 30 atom %.The light-shielding film 30 may contain carbon at a content of about 7 atom % to about 25 atom %.

[0110] The light-shielding film 30 may contain nitrogen at a content of about 3 atom % to about 20 atom %.The light-shielding film 30 may contain nitrogen at a content of about 5 atom % to about 15 atom %.

[0111] The light-shielding film 30 may contain oxygen at a content of about 20 atom % to about 45 atom %.The light-shielding film 30 may contain oxygen at a content of about 25 atom % to about 40 atom %.

[0112] In this case, the light-shielding film 30 can have sufficient light-extinguishing properties.

[0113] As shown in FIG. 11, the light-shielding film 30 may include a first light-shielding layer 301 and a second light-shielding layer 302 each containing a transition metal and at least one of oxygen and nitrogen.

[0114] The second light-shielding layer 302 may include a transition metal at a content of about 50 at % to about 80 at %. The second light-shielding layer 302 may include a transition metal at a content of about 55 at % to about 75 at %. The second light-shielding layer 302 may include a transition metal at a content of about 60 at % to about 70 at %. In the second light-shielding layer 302, a sum of an oxygen content and a nitrogen content may be about 10 at % to about 30 at %. In the second light-shielding layer 302, a sum of an oxygen content and a nitrogen content may be about 15 at % to about 25 at %. The second light-shielding layer 302 may include a nitrogen content of about 5 at % to about 15 at %. The second light-shielding layer 22 may include a nitrogen content of about 7 at % to about 13 at %.

[0115] The first light-shielding layer 301 may include a transition metal at a content of about 30 at % to about 60 at %. The first light-shielding layer 301 may include a transition metal at a content of about 35 at % to about 55 at %. The first light-shielding layer 301 may include a transition metal at a content of about 40 at % to about 50 at %. In the first light-shielding layer 301, a sum of an oxygen content and a nitrogen content may be about 40 at % to about 70 at %. In the first light-shielding layer 301, a sum of an oxygen content and a nitrogen content may be about 45 at % to about 65 at %. In the first light-shielding layer 301, a sum of an oxygen content and a nitrogen content may be about 50 at % to about 60 at %. The first light-shielding layer 301 may include an oxygen content of about 20 at % to about 37 at %. The first light-shielding layer 301 may contain oxygen at a content of about 23 at % to about 33 at %. The first light-shielding layer 301 may contain oxygen at a content of about 25 at % to about 30 at %. The first light-shielding layer 301 may contain nitrogen at a content of about 20 at % to about 35 at %. The first light-shielding layer 301 may contain nitrogen at a content of about 26 at % to about 33 at %. The first light-shielding layer 301 may contain nitrogen at a content of about 26 at % to about 30 at %.

[0116] The transition metal may include at least one of Cr, Ta, Ti, and Hf. The transition metal may be Cr.

[0117] In this case, the first light-shielding layer 31 can help the light-shielding film 30 to have excellent extinction properties.

[0118] The first light-shielding layer 31 may have a thickness of about 250 Å to about 650 Å. The first light-shielding layer 31 may have a thickness of about 350 Å to about 600 Å. The first light-shielding layer 31 may have a thickness of about 400 Å to about 550 Å. In this case, the first light-shielding layer 31 may help the light-shielding film 30 to effectively block exposure light.

[0119] The second light-shielding layer 32 may have a thickness of about 30 Å to about 200 Å. The second light-shielding layer 32 may have a thickness of about 30 Å to about 100 Å. The second light-shielding layer 32 may have a thickness of about 40 Å to about 80 Å. In this case, the second light-shielding layer 32 may improve the extinction characteristic of the light-shielding film 30 and help to more precisely control the surface profile of the side of the light-shielding pattern film 35 formed when the light-shielding film 30 is patterned.

[0120] A ratio of a thickness of the second light-shielding layer 32 to a thickness of the first light-shielding layer 31 may be about 0.05 to about 0.3. A ratio of a thickness of the second light-shielding layer 32 to a thickness of the first light-shielding layer 31 may be about 0.07 to about 0.25. A ratio of a thickness of the second light-shielding layer 32 to a thickness of the first light-shielding layer 31 may be about 0.1 to about 0.2.

[0121] In such a case, the light-shielding film 30 has sufficient extinction properties, and the surface profile of the side surface of the light-shielding pattern film 35 formed during patterning of the light-shielding film 30 can be controlled more precisely.

[0122] The second light-shielding layer 32 may have a transition metal content greater than that of the first light-shielding layer 31 .

[0123] In order to more precisely control the surface profile of the side of the light-shielding pattern film 35 formed by patterning the light-shielding film 30 and to ensure that the surface reflectance of the light-shielding film 30 to the inspection light in defect inspection has a value suitable for inspection, the second light-shielding layer 32 is required to have a larger transition metal content than the first light-shielding layer 31.

[0124] However, in this case, recovery, recrystallization, and crystal grain growth may occur in the transition metal contained in the second light-shielding layer 32 during heat treatment of the formed light-shielding film 30. If crystal grain growth occurs in the second light-shielding layer 32 containing a high content of transition metal, the surface illuminance characteristics of the light-shielding film 30 may fluctuate excessively due to overgrown transition metal particles. This may cause an increase in the number of false defects detected when the surface of the light-shielding film 30 is inspected for defects with high sensitivity.

[0125] The light-shielding film 30 may have a transmittance of about 1% to about 2% for light with a wavelength of 193 nm. The light-shielding film 30 may have a transmittance of about 1.3% to about 2% for light with a wavelength of 193 nm. The light-shielding film 30 may have a transmittance of about 1.4% to about 2% for light with a wavelength of 193 nm.

[0126] The light-shielding film 30 may have an optical density of about 1.8 to about 3. The light-shielding film 30 may have an optical density of about 1.9 to about 3.

[0127] In this case, the thin film including the light-shielding film 30 can effectively suppress the transmission of the exposure light.

[0128] As shown in FIG. 12, the optical substrate 10 may further include a phase shift film 40 .

[0129] The phase shift film 40 may be disposed between the light-transmitting substrate 20 and the light-shielding film 30. The phase shift film 40 may be a thin film that attenuates the intensity of the transmitted exposure light, adjusts the phase difference, and substantially suppresses diffracted light generated at the edge of a pattern.

[0130] The phase shift film 40 may have a phase difference of about 170° to about 190° with respect to light having a wavelength of 193 nm. The phase shift film 40 may have a phase difference of about 175° to about 185° with respect to light having a wavelength of 193 nm.

[0131] The phase shift film 40 may have a transmittance of about 3% to about 10% for light with a wavelength of 193 nm. The phase shift film 40 may have a transmittance of about 4% to about 8% for light with a wavelength of 193 nm. In such a case, the resolution of the photomask 200 including the phase shift film 40 may be improved.

[0132] The phase shifter film 40 may contain a transition metal and silicon. The phase shifter film 40 may contain a transition metal, silicon, oxygen, and nitrogen. The transition metal may be molybdenum.

[0133] A hard mask (not shown) may be located on the light-shielding film 30. The hard mask can function as an etching mask film when etching the pattern of the light-shielding film 30. The hard mask may contain silicon, nitrogen, and oxygen.

[0134] The manufacturing method of the optical substrate 10 includes a step of forming the light-shielding film 30 on the light-transmitting film. The light-shielding film 30 may be formed by a sputtering process.

[0135] After the sputtering process, a heat treatment process may be performed.

[0136] The heat treatment step can be performed at a temperature of about 200°C to about 400°C.

[0137] The heat treatment step may be performed for about 5 minutes to about 30 minutes.

[0138] The method for manufacturing the optical substrate 10 may further include a step of cooling the light-shielding film 30 that has been subjected to the heat treatment process.

[0139] The sputtering target can be selected in consideration of the composition of the light-shielding film 30 to be formed. The sputtering target can be one target containing a transition metal. The sputtering target can be two or more targets including one target containing a transition metal. The target containing a transition metal may contain 90 atom% or more of the transition metal. The target containing a transition metal may contain 95 atom% or more of the transition metal. The target containing a transition metal may contain 99 atom% of the transition metal.

[0140] The transition metal may include at least one of Cr, Ta, Ti, and Hf. The transition metal may include Cr.

[0141] The atmospheric gas may include an inert gas, a reactive gas, and a sputtering gas. The inert gas is a gas that does not contain elements that constitute the deposited thin film. The reactive gas is a gas that contains elements that constitute the deposited thin film.

[0142] The sputtering gas is a gas that is ionized in a plasma atmosphere and collides with a target. The inert gas may include helium.

[0143] The reactive gas may include a gas containing a nitrogen element. The gas containing a nitrogen element may be, for example, N2, NO, NO2, N2O, N2O3, N2O4, or N2O5. The reactive gas may include a gas containing an oxygen element.

[0144] The gas containing oxygen may be O2, for example. The reactive gas may include a gas containing nitrogen and a gas containing oxygen. The reactive gas may include a gas containing both nitrogen and oxygen. The gas containing both nitrogen and oxygen may be NO, NO2, N2O, N2O3, N2O4, or N2O5, for example.

[0145] The reactive gas containing carbon and oxygen may also be CO2.

[0146] The sputtering gas may be Ar gas.

[0147] The power source for applying power to the sputtering target may be a DC power source or an RF power source.

[0148] Thereafter, the cooled light-shielding film 30 can be washed. The washing step may include an ultraviolet irradiation step and / or a rinsing step.

[0149] The ultraviolet ray irradiation step may include a step of irradiating the light-shielding film 30 with ultraviolet rays.

[0150] The rinsing process includes treating the light-shielding film 30 with a cleaning solution. The cleaning solution may include at least one of deionized water, hydrogen water, ozone water, and carbonated water. The cleaning solution may include the carbonated water.

[0151] The optical substrate 10 may be disposed in the chamber 100. The optical substrate 10 may be temporarily fixed to the chuck 200. The optical substrate 10 may be disposed in the receiving portion. The optical substrate 10 may be seated on the chuck 200.

[0152] As shown in FIG. 13, the method for manufacturing a blank mask according to the embodiment includes forming a photoresist layer 50 on the optical substrate 10 .

[0153] In order to form the photoresist layer 50, the inside of the chamber 100 is isolated from the outside by a lid of the chamber 100. Then, while the chuck 200 is rotating at high speed, the photoresist resin composition is dropped and coated on the upper surface of the optical substrate 10 by the photoresist resin composition supply unit 500. As a result, a photoresist resin composition layer may be formed on the optical substrate 10.

[0154] The method for manufacturing a blank mask according to the embodiment includes discharging process by-products 511 generated during the formation of the photoresist layer 50 from a space between the side surface 12 of the optical substrate 10 and the chuck 200 by the compressed air.

[0155] When the photoresist resin composition is coated on the optical substrate 10, the first air pump 300 may supply the compressed air to the by-product removal unit 230. Thus, the process by-products 511 may be removed from the space 250 between the side surface 12 of the optical substrate 10 and the chuck 200. That is, the process by-products 511 may be discharged from the space 250 between the side surface 12 of the optical substrate 10 and the guide unit 220 by the by-product removal unit 230.

[0156] When the photoresist resin composition is coated on the optical substrate 10, the vacuum unit 300 may apply the vacuum pressure to the by-product removal unit 230. Thus, the process by-products 511 may be removed from the space 250 between the side surface 12 of the optical substrate 10 and the chuck 200. That is, the process by-products 511 may be discharged from the space 250 between the side surface 12 of the optical substrate 10 and the guide unit 220 by the by-product removal unit 230.

[0157] The step of removing the process by-products 511 and the step of rotating the optical substrate 10 at high speed by the chuck 200 can be performed simultaneously. That is, the step of forming the photoresist layer 50 and the step of discharging the process by-products 511 can be performed simultaneously.

[0158] The photoresist resin composition may contain a binder resin, a photosensitive resin, and an organic solvent.

[0159] Examples of the binder resin include novolac resin, phenolic resin, epoxy resin, polyimide resin, etc. Examples of the binder resin include polyvinyl pyrolidone, poly(acrylamide-co-diacetoneacrylamide), etc.

[0160] The photosensitive resin may contain a photosensitizer.

[0161] Examples of the photosensitizer include at least one selected from the group consisting of 4,4'-diazido-2,2'-stilbenedisulfonic acid sodium salt, 4,4'-diazo-2,2'-dibenzylideneacetonedisulfonic acid disodium salt, 2,5-bis(4-azido-2-sulfobenzylidene)cyclopentanone disodium salt, and 4,4'-diazido-2,2'-stilbenedisulfonic acid sodium salt (4,4'-diazido-2,2'-dicinnamylideneacetone sulfonate salt, DACA).

[0162] The solvents include ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, methyl methoxypropionate, ethyl ethoxypropionate (EEP), ethyl lactate, propylene glycol methyl ether acetate (PGMEA), propylene glycol methyl ether, propylene glycol propyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol methyl acetate, diethylene glycol ethyl acetate, acetone, methyl isobutyl ketone, and cyclohexanone. At least one of the solvents may be selected from the group consisting of dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), γ-butyrolactone, diethyl ether, ethylene glycol dimethyl ether, diglyme, tetrahydrofuran (THF), methanol, ethanol, propanol, isopropanol, methyl cellosolve, ethyl cellosolve, diethylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol methyl ether, toluene, xylene, hexane, heptane, and octane.

[0163] The photoresist resin composition may include the binder resin in an amount of about 3 wt % to about 50 wt %, the photosensitizer in an amount of about 2 wt % to about 40 wt %, and the solvent in an amount of about 10 wt % to about 94 wt %.

[0164] The photoresist resin composition may further include additives such as a leveling agent or an adhesion promoter.

[0165] As a result, the photoresist resin composition layer formed on the optical substrate 10 is dried and the solvent is removed. As a result, the photoresist layer 50 may be formed on the optical substrate 10, as shown in Fig. 13. As a result, a blank mask including the optical substrate 10 and the photoresist layer 50 can be manufactured.

[0166] The photoresist layer 50 may be selectively irradiated with light, and the light-shielding film may be selectively etched to form the light-shielding pattern film 35.

[0167] As shown in FIG. 14, a photomask 2 including the light-transmitting substrate 20 and the light-shielding pattern film 35 disposed on the light-transmitting substrate 20 may be formed.

[0168] The light-shielding pattern film 35 contains at least one of a transition metal, oxygen, and nitrogen.

[0169] The light-shielding pattern film 35 may be formed by patterning the light-shielding film 30 of the blank mask 100 described above.

[0170] Descriptions of the properties, composition, structure, etc. of the light-shielding pattern film 35 overlap with the description of the light-shielding film 30 of the blank mask 1, and therefore will be omitted.

[0171] The manufacturing method of a semiconductor device according to the embodiment includes a preparation step of arranging a light source, a photomask 2, and a semiconductor wafer coated with a resist film, an exposure step of selectively transmitting and emitting light incident from the light source through the photomask 2 onto the semiconductor wafer, and a development step of developing a pattern on the semiconductor wafer.

[0172] The photomask 2 includes a light-transmitting substrate 20 and a light-shielding pattern film 35 disposed on the light-transmitting substrate 20 .

[0173] The light-shielding pattern film 35 contains at least one of a transition metal, oxygen, nitrogen, and carbon.

[0174] In the preparation step, the light source is a device that generates short-wavelength exposure light. The exposure light may be light with a wavelength of 200 nm or less. The exposure light may be ArF light with a wavelength of 193 nm.

[0175] A lens may be further disposed between the photomask 2 and the semiconductor wafer. The lens serves to reduce the shape of the circuit pattern on the photomask 2 and transfer it onto the semiconductor wafer. The lens is not limited as long as it is generally applicable to the exposure process of ArF semiconductor wafers. As an example, the lens may be a lens made of calcium fluoride (CaF2).

[0176] In the exposure step, the exposure light can be selectively transmitted onto the semiconductor wafer through the photomask 2. In such a case, chemical modification can occur in the portion of the resist film on which the exposure light is incident.

[0177] In the developing step, the semiconductor wafer after the exposure step can be treated with a developing solution to develop a pattern on the semiconductor wafer. If the applied resist film is a positive resist, the portion of the resist film on which the exposure light is incident can be dissolved by the developing solution. If the applied resist film is a negative resist, the portion of the resist film on which the exposure light is not incident can be dissolved by the developing solution. The resist film is formed into a resist pattern by treatment with the developing solution. A pattern can be formed on the semiconductor wafer using the resist pattern as a mask.

[0178] The description of the photomask 2 is omitted here since it overlaps with the above description.

[0179] The manufacturing method of a blank mask according to the embodiment can minimize the adhesion 51 of the droplets to the side surface 12 of the light-transmitting substrate 20. In addition, the manufacturing method of a blank mask according to the embodiment can minimize the adhesion 52 of the droplets to the lower surface 13 of the light-transmitting substrate 20. That is, the manufacturing method of a blank mask according to the embodiment can minimize the droplet-like adhesion 51, 52 formed by the droplets on the side surface 12 and / or the lower surface 13 of the light-transmitting substrate 20.

[0180] As a result, the droplet-like adsorption 51 may not be present on the side surface 12 of the light-transmitting substrate 20. In addition, the droplet-like adsorption 52 may not be present on the lower surface 13 of the light-transmitting substrate 20. In other words, the number of droplet-like adsorptions 51, 52 on the side surface 12 and the lower surface 13 of the light-transmitting substrate 20 may be zero.

[0181] Alternatively, as shown in FIGS. 15 and 16, the droplet-like adsorption 51 may be formed on the side surface 12 of the light-transmitting substrate 20. In the example shown in FIG.

[0182] The droplet-like adsorption 51 may be formed by liquid droplets adsorbing to the side surface 12 of the light-transmitting substrate 20. The liquid droplets may be the fine particles described above. That is, the photoresist composition may be scattered into fine particles and deposited on the side surface 12 of the light-transmitting substrate 20, forming the droplet-like adsorption 51.

[0183] As shown in FIG. 17, the droplet-like adsorption 52 may be formed on the lower surface 13 of the light-transmitting substrate 20 .

[0184] The droplet-like adsorption 52 may be formed by the liquid droplets being adsorbed on the lower surface 13 of the light-transmitting substrate 20. That is, the photoresist composition may be scattered into fine particles and deposited on the lower surface of the light-transmitting substrate 20, thereby forming the droplet-like adsorption 52.

[0185] The droplets 51 and 52 contain the photoresist composition, and may contain substantially the same material as the photoresist layer.

[0186] The droplet-like adsorptions 51 and 52 may have a curved surface. The droplet-like adsorptions 51 and 52 may have a curved surface formed on the opposite surface to the adsorbed surface.

[0187] The droplet-like adsorptions 51, 52 may have an island shape. The droplet-like adsorptions 51, 52 may have a diameter (DA) of about 0.01 μm to about 10 μm.

[0188] On the side surface 12 of the light-transmitting substrate 20, the number of droplets 51 is about 4 / cm 2 The number of droplets 51 on the side surface 12 of the light-transmitting substrate 20 may be less than about 3 droplets / cm. 2 The number of droplets 51 on the side surface 12 of the light-transmitting substrate 20 may be less than about 2.5 droplets / cm. 2 The number of droplets 51 on the side surface 12 of the light-transmitting substrate 20 may be less than about 2 droplets / cm. 2 The number of droplets 51 on the side surface 12 of the light-transmitting substrate 20 may be less than about 1.5 droplets / cm. 2 The number of droplets 51 on the side surface 12 of the light-transmitting substrate 20 may be less than about 1 droplet / cm. 2 It may be less than.

[0189] The minimum number of droplets 51 on the side surface 12 of the light-transmitting substrate 20 is about 0.005 droplets / cm 2 may be also possible.

[0190] The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 is about 5 droplets / cm 2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 4 droplets / cm. 2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 3.5 droplets / cm 2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 3 droplets / cm. 2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 2.5 droplets / cm 2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 2 droplets / cm. 2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 1.5 droplets / cm2 The number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 may be less than about 1 droplet / cm. 2 It may be less than.

[0191] The minimum number of droplets 52 on the lower surface 13 of the light-transmitting substrate 20 is about 0.005 droplets / cm 2 may be also possible.

[0192] The droplets 51, 52 may include first droplets having a diameter of about 0.01 μm or more and less than about 0.04 μm.

[0193] The number of the first droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 2 droplets / cm 2 The number of the first droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 may be less than about 1.8 droplets / cm. 2 It may be less than.

[0194] The minimum number of the first droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 0.005 droplets / cm 2 may be also possible.

[0195] The number of the first droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 2.5 droplets / cm 2 The number of the first droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 may be less than about 2 droplets / cm. 2 It may be less than.

[0196] The minimum number of the first droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 0.005 droplets / cm 2 may be also possible.

[0197] The droplets 51, 52 may include second droplets having a diameter of about 0.04 μm or more and less than about 0.3 μm.

[0198] The number of the second droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 1 droplet / cm 2 The number of the second droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 may be less than about 0.5 droplets / cm. 2 It may be less than.

[0199] The minimum number of the second droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 0.005 droplets / cm 2 may be also possible.

[0200] The number of the second droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 1 droplet / cm 2 The number of the second droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 may be less than about 0.5 droplets / cm. 2 It may be less than.

[0201] The minimum number of the second droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 0.005 droplets / cm 2 may be also possible.

[0202] The droplets 51, 52 may include third droplets having a diameter of about 0.3 μm or more and less than about 3 μm.

[0203] The number of the third droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 1 droplet / cm 2 The number of the third droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 may be less than about 0.5 droplets / cm. 2 It may be less than.

[0204] The minimum number of the third droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 0 droplets / cm 2 may be also possible.

[0205] The number of the third droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 1 droplet / cm 2The number of the third droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 may be less than about 0.5 droplets / cm. 2 It may be less than.

[0206] The minimum number of the third droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 0 droplets / cm 2 may be also possible.

[0207] The droplets 51, 52 may include a fourth droplet having a diameter of about 3 μm or more and less than about 10 μm.

[0208] The number of the fourth droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 1 droplet / cm 2 The number of the fourth droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 may be less than about 0.5 droplets / cm. 2 It may be less than.

[0209] The minimum number of the fourth droplets adsorbed on the side surface 12 of the light-transmitting substrate 20 is about 0 droplets / cm 2 may be also possible.

[0210] The number of the fourth droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 1 droplet / cm 2 The number of the fourth droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 may be less than about 0.5 droplets / cm. 2 It may be less than.

[0211] The minimum number of the fourth droplets adsorbed on the lower surface 13 of the light-transmitting substrate 20 is about 0 droplets / cm 2 may be also possible.

[0212] As described above, the blank mask according to the embodiment can minimize optical distortion because it minimizes the droplet-like adhesion 51, 52. In particular, the blank mask according to the embodiment can further minimize optical distortion because it minimizes the relatively large droplet-like adhesion as described above.

[0213] The method for manufacturing a blank mask according to the embodiment includes a step of removing splashes generated during the step of forming the photoresist layer, thereby preventing the side surface 12 and / or the lower surface 13 of the light-transmitting substrate 20 from being contaminated by process by-products such as splashes.

[0214] In particular, the method for manufacturing a blank mask according to the embodiment can use compressed air or vacuum pressure to remove droplets scattered from the photoresist composition to form the photoresist layer from the side surface 12 of the light-transmitting substrate 20 .

[0215] As a result, the method for manufacturing a blank mask according to the embodiment can effectively prevent the droplets from being adsorbed on the side surface 12 and the lower surface 13 of the light-transmitting substrate 20 .

[0216] As a result, in the method for manufacturing a blank mask according to the embodiment, the droplet-like adsorption 51 on the side surface 12 of the light-transmitting substrate 20 is 3 droplets / cm 2 In addition, in the method for producing a blank mask according to the embodiment, it is possible to provide a blank mask in which the droplet-like adsorption 52 on the lower surface 13 of the light-transmitting substrate 20 is less than 4 droplets / cm. 2 A blank mask can be provided that is less than

[0217] As a result, the blank mask manufacturing method according to the embodiment can minimize optical distortion caused by the droplet-like adsorption 51 and 52. As a result, the blank mask manufacturing method according to the embodiment can have improved optical performance.

[0218] In addition, as described above, the manufacturing method of the blank mask according to the embodiment does not use an additional process for removing the droplets adsorbed to the side surface 12 and lower surface 13 of the light-transmitting substrate 20 in order to suppress the droplet-like adsorption 51, 52.

[0219] Therefore, the method for manufacturing a blank mask according to the embodiment can prevent the photoresist layer from being damaged by an additional process for removing the droplet-like adhesion.

[0220] In the blank mask according to the embodiment, the number of droplet-like adsorptions 51, 52 on the side surface 12 and the bottom surface 13 of the light-transmitting substrate 20 is small, so that optical distortion can be minimized and optical performance can be improved.

[0221] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the claims below also fall within the scope of the present invention.

[0222] Example 1 The resist coating was performed using an 8.5% solution of FEP171 (manufactured by FUJIFILM Arch Co., Ltd.) FEP171 is a positron beam resist, and the solvent of the solution is a mixed solution of PGMEA (propylene glycol monomethly ether acetate) and PGME (propylene glycol monomethyl ether) in a ratio of 8:2.

[0223] A quartz substrate having a size of about 6 inches by about 6 inches was used, and the quartz substrate had a thickness of 0.25 inches. The quartz substrate was mounted on a support and inside a guide. The distance between the guide and the quartz substrate was 0.5 mm, and the height difference between the guide and the quartz substrate was 0.5 mm.

[0224] In addition, through holes having a diameter of about 1 mm are arranged at a pitch of about 25 mm along the outer periphery of the support part. Compressed air is continuously injected through the through holes at a speed of about 3 ml / sec.

[0225] After the FEP171 solution was dropped onto the quartz substrate, the main rotation speed was changed stepwise at 250 rpm intervals (five conditions) within the range of about 750 rpm to about 1750 rpm, and the main rotation time was changed stepwise at 1 sec intervals (five conditions) within the range of 1 to 5 sec. The drying rotation speed was fixed at 300 rpm.

[0226] In this way, an optical substrate having a photoresist layer formed thereon was produced.

[0227] Examples 2 to 5 and Comparative Example The speed of the compressed air is adjusted as shown in Table 1 below. The other steps refer to Example 1.

[0228] [Table 1]

[0229] Evaluation example 1. Number of droplets adsorbed The number of droplets adsorbed on the side and bottom surfaces of the quartz substrate in the optical substrates manufactured in the examples and comparative examples was measured using an optical surface inspection device (LASERTEC M6641S).

[0230] The number of droplets adsorbed on the side surface of the quartz substrate is calculated by particle size as shown in Table 2 below.

[0231] [Table 2]

[0232] The number of droplets adsorbed on the lower surface of the quartz substrate is calculated by particle size as shown in Table 2 below.

[0233] [Table 3]

[0234] As shown in Tables 2 and 3 above, in the optical substrates according to the examples, the number of droplets adsorbed was very small, and there was almost no edge bead. [Explanation of symbols]

[0235] 100 Chamber 200 Chuck 300 First Air Pump 400 Exhaust section 500 Photoresist resin composition supply section 600 Second Air Pump 610 Air Sweep Section

Claims

1. A method for manufacturing a blank mask, comprising the steps of: forming a light-shielding film on a light-transmitting substrate to form an optical substrate; forming a photoresist layer on the light-shielding film; removing splashes generated during the step of forming the photoresist layer from a side surface of the light-transmitting substrate; The droplet adsorption rate on the side surface of the light-transmitting substrate is 3 droplets / cm ２ is less than The method further includes the step of mounting the optical substrate on a chuck, The step of forming the photoresist layer comprises: Dropping a photoresist composition onto the light-shielding film; rotating the optical substrate; injecting compressed air between the optical substrate and the chuck; Including, The steps of rotating the optical substrate and spraying the compressed air are performed simultaneously. A method for manufacturing a blank mask.

2. The chuck is A support portion that supports the optical substrate; A guide portion disposed on a side surface of the optical substrate; Including, In the step of rotating the optical substrate, the optical substrate and the guide portion are rotated simultaneously, The compressed air is injected between the guide portion and the side surface of the optical substrate. A method for producing the blank mask according to claim 1 .

3. A method for manufacturing a blank mask, comprising the steps of: forming a light-shielding film on a light-transmitting substrate to form an optical substrate; forming a photoresist layer on the light-shielding film; removing splashes generated during the step of forming the photoresist layer from a side surface of the light-transmitting substrate; the number of droplets adsorbed on the side surface of the light-transmitting substrate originating from the droplets is less than 3 droplets / cm 2 ; The method further includes the step of mounting the optical substrate on a chuck, The step of forming the photoresist layer comprises: Dropping a photoresist composition onto the light-shielding film; rotating the optical substrate; applying a vacuum pressure between a side of the optical substrate and the chuck; Including, The steps of rotating the optical substrate and applying the vacuum pressure are performed simultaneously. A method for manufacturing a blank mask.

4. The chuck is A support portion that supports the optical substrate; A guide portion disposed on a side surface of the optical substrate; Including, In the step of rotating the optical substrate, the optical substrate and the guide portion are rotated simultaneously, The vacuum pressure is applied between the guide portion and the side surface of the optical substrate. The method for producing the blank mask according to claim 3 .

5. The droplet adsorption rate on the lower surface of the light-transmitting substrate is 4 droplets / cm ２ is less than A method for producing the blank mask according to claim 1 .

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