Blank mask and method for manufacturing blank mask

Abstract

To provide a blank mask from which a photomask that is precisely patterned and has less optical strains can be provided, and a method for manufacturing the same.SOLUTION: A method for manufacturing a blank mask includes the steps of: forming a light-shielding film on a light-transmitting substrate, and forming an optical substrate; preparing a nozzle for injecting a photoresist resin composition onto the optical substrate; filling the nozzle with the photoresist resin composition, and maintaining the state in which the nozzle is filled with the photoresist resin composition; removing the photoresist resin composition from the inside of the nozzle; and forming a photoresist layer on the light-shielding film, using the nozzle.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Due to the high integration of semiconductor devices and the like, miniaturization of the circuit patterns of semiconductor devices is required. As a result, the importance of lithography technology, which is a technique for developing circuit patterns on a wafer surface using a photomask, is further emphasized.

[0003] In order to develop miniaturized circuit patterns, a shorter wavelength of the exposure light source used in the exposure process is required. In recent years, among the exposure light sources used, there is an ArF excimer laser (wavelength 193 nm) and the like.

[0004] On the other hand, photomasks include a binary mask, a phase shift mask, and the like.

[0005] The binary mask has a configuration in which a light-shielding layer pattern is formed on a light-transmissive substrate. In the binary mask, on the surface where the pattern is formed, the transmissive portion that does not include the light-shielding layer transmits the exposure light, and the light-shielding portion that includes the light-shielding layer blocks the exposure light, thereby exposing the pattern on the resist film on the wafer surface. However, in the binary mask, as the pattern becomes more miniaturized, problems may occur in the development of the fine pattern due to the diffraction of light generated at the edge of the transmissive portion in the exposure process.

[0006] There are Levenson type, Outrigger type, and Half-tone type in phase shift masks. Among them, the half-tone type phase shift mask has a structure in which a pattern formed of a semi-transmissive film is formed on a light-transmissive substrate 20. In the half-tone type phase shift mask, in the plane where the pattern is formed, the transmissive portion that does not include the semi-transmissive layer transmits the exposure light, and the semi-transmissive portion that includes the semi-transmissive 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 canceled out by the exposure light that has passed through the semi-transmissive portion, and the phase shift mask can form a more delicate fine pattern on the wafer surface.

Prior Art Documents

Patent Documents

[0007] The prior documents related to this are as follows.

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] An embodiment aims to provide a blank mask that can be precisely patterned and provide a photomask with less optical distortion, and a method for manufacturing the same.

Means for Solving the Problems

[0009] The method for manufacturing a blank mask according to an embodiment includes forming a light-shielding film on a light-transmissive substrate to form an optical substrate, preparing a nozzle for injecting a photoresist resin composition onto the optical substrate, filling the nozzle with the photoresist resin composition, and maintaining a state in which the inside of the nozzle is filled with the photoresist resin composition, removing the photoresist resin composition from the inside of the nozzle, and forming a photoresist layer on the light-shielding film using the nozzle.

[0010] In the method for manufacturing a blank mask according to an embodiment, the photoresist layer includes a flat portion disposed on the light-shielding film and optical irregularities having an optical thickness different from that of the flat portion. The optical irregularities are detected by a laser of 532 nm and may be disposed on the light-shielding film at less than 30 pieces / 36 inches. 2 It may be arranged.

[0011] In the method for manufacturing a blank mask according to an embodiment, in the step of maintaining a state in which the inside of the nozzle is filled with the photoresist resin composition, a part of the photoresist resin composition may be exposed to the outside from the inlet of the nozzle.

[0012] In the method for manufacturing a blank mask according to an embodiment, in a state where the inside of the nozzle is filled with the photoresist composition, it can be maintained for about 30 seconds to about 300 minutes.

[0013] In the method for manufacturing a blank mask according to an embodiment, in the step of maintaining a state in which the inside of the nozzle is filled with the photoresist resin composition, the residue attached to the inside of the nozzle can be detached from the inner surface of the nozzle.

[0014] In the method for manufacturing a blank mask according to an embodiment, the step of maintaining a state in which the inside of the nozzle is filled with the photoresist resin composition can be maintained until the residue detaches from the inner surface of the nozzle.

[0015] In the method for manufacturing a blank mask according to an embodiment, the optical unevenness is 20 pieces / 36 inches 2 It may be less.

[0016] The blank mask according to the embodiment includes a light-transmissive substrate, a light-shielding film disposed on the light-transmissive substrate, and a photoresist layer disposed on the light-shielding film. The photoresist layer includes a flat portion disposed on the light-shielding film, and the optical unevenness includes optical unevenness detected by a laser of 532 nm. The optical unevenness is disposed on the light-shielding film at less than 30 pieces / 36 inches 2 It is arranged less than.

[0017] In the blank mask according to an embodiment, the optical unevenness may be less than 20 pieces / 36 inches 2 It may be less.

[0018] In the blank mask according to an embodiment, the optical unevenness may have a refractive index different from that of the photoresist layer.

[0019] In the blank mask according to an embodiment, the optical unevenness may have a thickness different from that of the photoresist layer.

[0020] In the blank mask according to an embodiment, the optical unevenness may have an optical thickness different from that of the flat portion.

[0021] In the blank mask according to an embodiment, the optical unevenness may include a light path changing portion.

[0022] In the blank mask according to an embodiment, the light path changing portion may have a refractive index different from that of the flat portion.

[0023] The method for manufacturing a blank mask according to an embodiment may include: forming a light-shielding film on a light-transmissive substrate to form an optical substrate; preparing a nozzle for injecting a photoresist resin composition onto the optical substrate; filling the nozzle with the photoresist resin composition to detach residues from the inner surface of the nozzle; removing the photoresist resin composition and the detached residues from the inside of the nozzle; and forming a photoresist layer on the light-shielding film using the nozzle.

[0024] In the method for manufacturing a blank mask according to an embodiment, the residues can adhere to and detach from the photoresist resin composition filled inside the nozzle while adhering to the inner surface of the nozzle.

[0025] In the method for manufacturing a blank mask according to an embodiment, it can be maintained for about 30 seconds to about 300 minutes with the photoresist resin composition filled inside the nozzle.

[0026] In the method for manufacturing a blank mask according to an embodiment, the residues may have a refractive index different from that of the photoresist layer.

[0027] In the method for manufacturing a blank mask according to an embodiment, the photoresist resin composition may be a liquid, and the residues may be solids.

[0028] In the method for manufacturing a blank mask according to an embodiment, the optical unevenness may be less than 20 pieces / 36 inches. 2 It may be less.

Advantages of the Invention

[0029] The method for manufacturing a blank mask according to an embodiment includes a step of maintaining the inside of a nozzle for injecting a photoresist resin composition filled with the photoresist resin composition. Further, the method for manufacturing a blank mask according to an embodiment includes a step of removing the photoresist resin composition inside the nozzle. Thereby, residues adhering to the inside of the nozzle can be easily removed.

[0030] Thereby, the method for manufacturing a blank mask according to an embodiment can prevent the residues from flowing into the photoresist layer.

[0031] Thereby, the blank mask according to an embodiment can reduce the number of optical irregularities that may be caused by the residues or the like. The blank mask according to an embodiment may include the optical irregularities of less than 30 pieces / 36 inches 2 and may include the optical irregularities.

[0032] Thereby, the method for manufacturing a blank mask according to an embodiment can implement a photoresist layer having optical flatness as a whole. Thereby, the photoresist layer can precisely pattern the light-shielding film.

[0033] In particular, since the photoresist layer has the optical irregularities detected by a laser of 532 nm in the above-described number as described above, it can be precisely developed by ultraviolet rays.

[0034] Thereby, the blank mask according to an embodiment can provide a photomask having a precise pattern.

Brief Description of Drawings

[0035]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

MODE FOR CARRYING OUT THE INVENTION

[0036] Hereinafter, the embodiments will be described in detail so that those having ordinary knowledge in the technical field to which the embodiments belong can easily implement them. However, the embodiments can be implemented in various different forms and are not limited to the embodiments described herein.

[0037] Terms such as "about" and "substantially" used in this specification are used in the meaning of or close to that numerical value when manufacturing and material tolerances inherent to the mentioned meaning are presented, and are used to prevent the content of the disclosure in which exact or absolute numerical values are mentioned for understanding the embodiments from being improperly used by unscrupulous infringers.

[0038] Throughout this specification, the term "these combinations" included in the Markush-type expressions means one or more mixtures or combinations selected from the group consisting of the components described in the Markush-type expressions, and means including one or more selected from the group consisting of the above components.

[0039] Throughout this specification, the description "A and / or B" means "A, B, or A and B".

[0040] Throughout this specification, terms such as "first", "second" or "A", "B" are used to distinguish the same terms from each other unless otherwise specified.

[0041] In this specification, the meaning that B is located on A means that B is located on A, or B may be located on A while another layer is located therebetween, and is not construed as being limited to the case where B is located in contact with the surface of A.

[0042] In this specification, a singular expression is construed to include the singular or plural as construed in the context, unless otherwise specified.

[0043] FIG. 1 is a cross-sectional view showing a cross-section of an optical substrate according to an embodiment. FIG. 2 is a cross-sectional view showing a cross-section of an optical substrate according to another embodiment. FIG. 3 is a cross-sectional view showing a cross-section of an optical substrate according to still another embodiment. FIG. 4 is a schematic view showing a manufacturing apparatus for a blank mask according to an embodiment. FIGS. 5 and 6 are views showing a process of removing residues adhered in a nozzle. FIG. 7 is a cross-sectional view showing a cross-section of a blank mask according to an embodiment. FIG. 8 is an enlarged cross-sectional view showing a cross-section of a blank mask according to an embodiment. FIG. 9 is a cross-sectional view showing a cross-section of a photomask according to an embodiment.

[0044] The blank mask according to the embodiment may be manufactured by the following manufacturing process.

[0045] First, as shown in FIGS. 1 to 3, the optical substrate 10 can be provided. The optical substrate 10 includes a light-transmissive substrate 20 and a light-shielding film 30 located on the light-transmissive substrate 20.

[0046] The light-transmissive substrate 20 may have light transmissivity with respect to exposure light. The light-transmissive substrate 20 may have a transmittance of more than about 85% with respect to exposure light having a wavelength of about 193 nm. The transmittance of the light-transmissive substrate 20 may be more than about 87%. The transmittance of the light-transmissive substrate 10 may be less than 99.99%. The light-transmissive substrate 20 may include a synthetic quartz substrate. In such a case, the light-transmissive substrate 20 can suppress attenuation of the transmitted light.

[0047] Since the light-transmissive substrate 20 has surface characteristics such as appropriate flatness and appropriate illuminance, distortion of the transmitted light can be suppressed.

[0048] The light-shielding film 30 may be disposed on the top side of the light-transmissive substrate 20.

[0049] The light-shielding film 30 can at least selectively block exposure light incident on the bottom side of the light-transmissive substrate 20.

[0050] Also, as shown in FIG. 3, when a phase shift film 40 or the like is disposed between the light-transmissive substrate 20 and the light-shielding film 30, the light-shielding film 30 can be used as an etching mask in the process of etching the phase shift film 40 or the like in accordance with the pattern shape.

[0051] The light-shielding film 30 may contain at least any one of a transition metal, oxygen, and nitrogen.

[0052] The light-shielding film 30 may contain chromium, oxygen, nitrogen, and carbon. The element-by-element content with respect to the entire light-shielding film 30 may vary in the thickness direction. The element-by-element content with respect to the entire light-shielding film 30 may vary layer by layer in the case of a multi-layer light-shielding film 30.

[0053] The light-shielding film 30 may contain chromium in a content of about 44 atom% to about 60 atom%. The light-shielding film 30 may contain chromium in a content of about 47 atom% to about 57 atom%.

[0054] The light-shielding film 30 may contain carbon in a content of about 5 atom% to 30 atom%. The light-shielding film 30 may contain carbon in a content of about 7 atom% to about 25 atom%.

[0055] The light-shielding film 30 may contain nitrogen in a content of about 3 atom% to about 20 atom%. The light-shielding film 30 may contain nitrogen in a content of about 5 atom% to about 15 atom%.

[0056] The light-shielding film 30 may contain oxygen in a content of about 20 atom% to about 45 atom%. The light-shielding film 30 may contain oxygen in a content of about 25 atom% to about 40 atom%.

[0057] In such a case, the light-shielding film 30 may have sufficient light extinction characteristics.

[0058] As shown in FIG. 2, the light-shielding film 30 may include a first light-shielding layer 31 and a second light-shielding layer 32 disposed on the first light-shielding layer 31.

[0059] The second light-shielding layer 32 contains a transition metal. Further, the second light-shielding layer 32 may contain at least one of oxygen, nitrogen, and carbon. The second light-shielding layer 32 may contain a transition metal in a content of about 50 atom% to about 80 atom%. The second light-shielding layer 32 may contain a transition metal in a content of about 55 atom% to about 75 atom%. The second light-shielding layer 32 may contain a transition metal in a content of about 60 atom% to about 70 atom%.

[0060] The content of the element corresponding to at least one of oxygen, nitrogen, or carbon in the second light-shielding layer 32 may be from about 10 atom% to about 35 atom%. The content of the element corresponding to at least one of oxygen, nitrogen, or carbon in the second light-shielding layer 32 may be from about 15 atom% to about 25 atom%.

[0061] The second light-shielding layer 32 may contain nitrogen in a content of about 5 atom% to about 20 atom%. The second light-shielding layer 32 may contain nitrogen in a content of about 7 atom% to about 13 atom%.

[0062] The second light-shielding layer 32 may contain oxygen in a content of about 5 atom% to about 20 atom%. The second light-shielding layer 32 may contain oxygen in a content of about 7 atom% to about 13 atom%.

[0063] The second light-shielding layer 32 may contain carbon in a content of about 2 atom% to about 10 atom%. The second light-shielding layer 32 may contain nitrogen in a content of about 37 atom% to about 8 atom%.

[0064] The second light-shielding layer 32 may contain all of nitrogen, oxygen, and carbon.

[0065] In such a case, the light-shielding film 30 can assist in forming a laminate with the phase shift film 40 to substantially block the exposure light.

[0066] The first light-shielding layer 31 may contain a transition metal. The first light-shielding layer 31 may contain oxygen and nitrogen. The first light-shielding layer 31 may contain a transition metal in an amount of 30 atom% or more and 60 atom% or less. The light-shielding layer 21 may contain a transition metal in an amount of 35 atom% or more and 55 atom% or less. The first light-shielding layer 31 may contain a transition metal in an amount of 40 atom% or more and 50 atom% or less.

[0067] The sum of the oxygen content and the nitrogen content of the first light-shielding layer 31 may be 40 atom% or more and 70 atom% or less. The sum of the oxygen content and the nitrogen content of the first light-shielding layer 31 may be 45 atom% or more and 65 atom% or less. The sum of the oxygen content and the nitrogen content of the first light-shielding layer 31 may be 50 atom% or more and 60 atom% or less.

[0068] The first light-shielding layer 31 may contain oxygen in an amount of 20 atom% or more and 40 atom% or less. The first light-shielding layer 31 may contain oxygen in an amount of 23 atom% or more and 33 atom% or less. The first light-shielding layer 31 may contain oxygen in an amount of 25 atom% or more and 30 atom% or less.

[0069] The first light-shielding layer 31 may contain nitrogen in an amount of 5 atom% or more and 20 atom% or less. The first light-shielding layer 31 may contain nitrogen in an amount of 7 atom% or more and 17 atom% or less. The first light-shielding layer 31 may contain nitrogen in an amount of 10 atom% or more and 15 atom% or less.

[0070] In such a case, the first light-shielding layer 31 can assist the light-shielding film 30 to have excellent light extinction characteristics.

[0071] The transition metal may contain at least one of Cr, Ta, Ti, and Hf. The transition metal may be Cr.

[0072] The thickness of the first light-shielding layer 31 may be about 250 Å to about 650 Å. The thickness of the first light-shielding layer 31 may be about 350 Å to about 600 Å. The thickness of the first light-shielding layer 31 may be about 400 Å to about 550 Å. In such a case, the first light-shielding layer 31 can assist the light-shielding film 30 to effectively block the exposure light.

[0073] The thickness of the second light-shielding layer 32 may be about 30 Å to about 200 Å. The thickness of the second light-shielding layer 32 may be about 30 Å or more and about 100 Å. The thickness of the second light-shielding layer 32 may be about 40 Å to about 80 Å. In such a case, the second light-shielding layer 32 can assist in improving the light extinction characteristics of the light-shielding film 30 and further precisely controlling the surface profile of the side surface of the light-shielding pattern film 35 formed during patterning of the light-shielding film 30.

[0074] The ratio of the thickness of the second light-shielding layer 32 to the thickness of the first light-shielding layer 31 may be about 0.05 to about 0.3. The ratio of the thickness of the second light-shielding layer 32 to the first light-shielding layer 31 may be about 0.07 to about 0.25. The ratio of the thickness of the second light-shielding layer 32 to the first light-shielding layer 31 may be about 0.1 to about 0.2.

[0075] In such a case, the light-shielding film 30 has sufficient light extinction characteristics and can further precisely control the surface profile of the side surface of the light-shielding pattern film 35 formed during patterning of the light-shielding film 30.

[0076] The content of the transition metal in the second light-shielding layer 32 may have a value even larger than the content of the transition metal in the first light-shielding layer 31.

[0077] In order to more precisely control the surface profile of the side surface of the light-shielding pattern film 35 formed by patterning the light-shielding film 30 and make the surface reflectivity of the light-shielding film 30 with respect to the inspection light in defect inspection have a value suitable for inspection, it may be required that the second light-shielding layer 32 has a value with an even larger content of transition metal with respect to the first light-shielding layer 31.

[0078] However, in such a case, during the heat treatment of the formed light-shielding film 30, the transition metal contained in the second light-shielding layer 32 may undergo recovery, recrystallization, and grain growth. When 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 vary excessively due to the overgrown transition metal particles. This may cause an increase in the number of pseudo defect detections when inspecting the surface of the light-shielding film 30 with high sensitivity.

[0079] The light-shielding film 30 may have a transmittance of about 1% to about 2% with respect to light having a wavelength of 193 nm. The light-shielding film 30 may have a transmittance of about 1.3% to about 2% with respect to light having a wavelength of 193 nm. The light-shielding film 30 may have a transmittance of about 1.4% to about 2% with respect to light having a wavelength of 193 nm.

[0080] 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.

[0081] In such a case, the thin film including the light-shielding film 30 can effectively suppress the transmission of exposure light.

[0082] As shown in FIG. 3, the optical substrate 10 may further include a phase shift film 40.

[0083] The phase shift film 40 may be disposed between the light-transmissive 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 the diffracted light generated at the edge of the pattern.

[0084] 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.

[0085] The phase shift film 40 may have a transmittance of about 3% to about 10% with respect to light having a wavelength of 193 nm. The phase shift film 40 may have a transmittance of about 4% to about 8% with respect to light having a wavelength of 193 nm. In such a case, the resolution of the photomask 200 including the phase shift film 40 can be improved.

[0086] The phase shift film 40 may contain a transition metal and silicon. The phase shift film 40 may contain a transition metal, silicon, oxygen, and nitrogen. The transition metal may be molybdenum.

[0087] 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.

[0088] The method for manufacturing the optical substrate 10 includes a step of forming the light-shielding film 30 on the light-transmissive substrate 20. The light-shielding film 30 may be formed by a sputtering process.

[0089] After the sputtering process is performed, a heat treatment process can be performed.

[0090] The heat treatment step can be performed at a temperature of about 200°C to about 400°C.

[0091] The heat treatment step can be performed for about 5 minutes to about 30 minutes.

[0092] Further, the method for manufacturing the optical substrate 10 may further include a step of cooling the light-shielding film 30 that has undergone the heat treatment process.

[0093] The sputtering target can be selected in consideration of the composition of the light-shielding film 30 to be formed. A single target containing a transition metal can be applied as the sputtering target. The sputtering target can include a single target containing a transition metal, and two or more targets can be applied. 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.

[0094] The transition metal may include at least one of Cr, Ta, Ti, and Hf. The transition metal may include Cr.

[0095] The atmosphere gas may include an inert gas, a reactive gas, and a sputtering gas. The inert gas is a gas that does not contain the elements constituting the formed thin film. The reactive gas is a gas that contains the elements constituting the formed thin film.

[0096] The sputtering gas is a gas that is ionized in a plasma atmosphere and collides with the target. The inert gas may include helium.

[0097] The reactive gas may include a gas containing a nitrogen element. Examples of the gas containing a nitrogen element may include N2, NO, NO2, N2O, N2O3, N2O4, or N2O5. The reactive gas may include a gas containing an oxygen element.

[0098] The gas containing the oxygen element may be, for example, O2. The reactive gas may include a gas containing a nitrogen element and a gas containing an oxygen element. The reactive gas may include a gas containing both a nitrogen element and an oxygen element. The gas containing both the nitrogen element and the oxygen element may be, for example, NO, NO2, N2O, N2O3, N2O4, or N2O5.

[0099] Further, the reactive gas containing carbon and oxygen may be CO2.

[0100] The sputtering gas may be Ar gas.

[0101] As the power supply for applying power to the sputtering target, a DC power supply can be used, or an RF power supply can also be used.

[0102] Thereafter, the cooled light-shielding film 30 can be washed. The washing process may include an ultraviolet irradiation process and / or a rinsing process.

[0103] The ultraviolet irradiation process may include a step of irradiating the light-shielding film 30 with ultraviolet rays.

[0104] The rinsing process includes a step of treating the light-shielding film 30 with a cleaning liquid. The cleaning liquid may include at least one of deionized water, hydrogen water, ozone water, or carbonated water. The cleaning liquid may include the carbonated water.

[0105] As shown in FIG. 4, a coating device is provided to form a photoresist layer 50 on the optical substrate 10. The coating device includes a chamber 100, a chuck 200, an exhaust unit 400, a supply unit 500 for a photoresist resin composition, and a spindle motor 700.

[0106] The chamber 100 houses the chuck 200. The chamber 100 can accommodate the optical substrate 10 for manufacturing a blank mask. The chamber 100 can isolate its interior from the outside. The interior of the chamber 100 can be sealed. The internal pressure of the chamber 100 can be under a vacuum lower than atmospheric pressure.

[0107] Also, the chamber 100 may include an openable / closable door or cover. The chamber 100 may be provided with a heater or the like capable of adjusting the internal temperature of the chamber 100.

[0108] The chuck 200 may include a support portion and a guide portion.

[0109] The support portion can support the guide portion. The support portion supports the optical substrate 10. The support portion may be disposed below the optical substrate 10.

[0110] The support portion can temporarily fix the optical substrate 10. The support portion can temporarily fix the optical substrate 10 by vacuum pressure or electrostatic force.

[0111] The guide portion may be connected to the support portion. The guide portion may be integrally formed with the support portion 210. The guide portion may be disposed on the side surface of the optical substrate 10. The guide portion may surround the side surface of the optical substrate 10.

[0112] The support portion and the guide portion can form a receiving portion for housing the optical substrate 10. That is, the support portion may be disposed on the lower surface of the optical substrate 10, and the guide portion may be disposed on the side surface of the optical substrate 10, and the receiving portion may be configured.

[0113] The accommodating portion can correspond to the planar shape of the optical substrate 10. The planar shape of the accommodating portion 240 may be substantially similar to the planar shape of the optical substrate 10. The planar shape of the optical substrate 10 is square, and the planar shape of the accommodating portion may also be square.

[0114] The outer contour of the guiding portion may be circular. The guiding portion and the supporting portion may be circular.

[0115] The exhaust portion 400 can exhaust the internal gas of the chamber 100. Further, the exhaust portion 400 can discharge the photoresist composition remaining after coating on the optical substrate 10. The exhaust portion 400 can discharge the photoresist resin composition scattered to the side of the chuck 200.

[0116] The supply portion 500 of the photoresist resin composition can supply the photoresist resin composition 510 to the upper surface of the optical substrate 10. The photoresist resin composition 510 may include an injection nozzle 520 disposed in the chamber 100. Through the injection nozzle 520, the photoresist resin composition 510 can drop onto the optical substrate 10. That is, the supply portion 500 of the photoresist resin composition can inject the photoresist resin composition 510 onto the upper surface of the optical substrate 10.

[0117] The photoresist resin composition may be a negative-type photosensitive radiation-sensitive or radiation-sensitive resin composition. The photoresist composition is a resist composition for forming a negative-type pattern, and may be a negative-type resist composition for organic solvent development or a negative-type resist composition for alkali development. The photoresist resin composition may typically be a chemically amplified resist composition.

[0118] The photoresist resin composition may include a binder resin, a photosensitizer, and an organic solvent.

[0119] Examples of the binder resin include novolak resins, phenolic resins, epoxy resins, or polyimide resins. Examples of the binder resin include polyvinyl pyrrolidone or poly(acrylamide-co-diacetone acrylamide).

[0120] Examples of the photosensitizer can include at least one selected from the group consisting of sodium 4,4'-diazido-2,2'-stilbenedisulfonate, disodium 4,4'-diazonio-2,2'-dibenzalacetone disulfonate, disodium 2,5-bis(4-azido-2-sulfobenzylidene)cyclopentanone, or sodium 4,4'-diazido-2,2'-stilbenedisulfonate (4,4'-diazido-2,2'-dicinnamylideneacetone sulfonate salt, DACA).

[0121] The solvent can be selected from at least one or more of the group consisting of ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethyl ethyl ether, dipropylene glycol dimethyl ether, methyl methoxy propionate, ethyl ethoxy propionate (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, cyclohexanone, 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.

[0122] The content of the solid component excluding the solvent in the photoresist resin composition may be about 3 wt% to about 20 wt% based on the total weight. The content of the solid component excluding the solvent in the photoresist resin composition may be about 3 wt% to about 15 wt% based on the total weight. The content of the solid component excluding the solvent in the photoresist resin composition may be about 5 wt% to about 10 wt% based on the total weight.

[0123] The photoresist resin composition may contain the binder resin in a content of about 2 wt% to about 50 wt% based on the total weight. The photoresist resin composition may contain the binder resin in a content of about 3 wt% to about 15 wt%.

[0124] The photoresist composition may contain the photosensitizer in a content of about 0.5 wt% to about 40 wt%. The photoresist composition may contain the photosensitizer in a content of about 0.5 wt% to about 20 wt%. The photoresist composition may contain the photosensitizer in a content of about 0.5 wt% to about 10 wt%. The photoresist composition may contain the photosensitizer in a content of about 0.5 wt% to about 5 wt%.

[0125] The viscosity of the photoresist composition may be about 0.5 cPs to about 10 cPs. The viscosity of the photoresist composition may be about 1 cPs to about 5 cPs. The viscosity of the photoresist composition may be about 0.5 cPs to about 5 cPs. The viscosity of the photoresist composition may be about 1 cPs to about 4 cPs.

[0126] The photoresist resin composition may further contain additives such as a leveling agent or an adhesion auxiliary agent.

[0127] As shown in FIGS. 5 and 6, in order to form the photoresist layer 50 on the optical substrate 10, the operation of the coating device can be provided.

[0128] First, the inside of the nozzle 520 of the coating device can be processed by the following method.

[0129] As shown in FIG. 5, the inside of the nozzle 520 is filled with the photoresist resin composition 512. The inside of the nozzle 520 may be entirely filled with the photoresist resin composition 512. Also, a part 511 of the photoresist resin composition may adhere to the inlet of the nozzle 520. Thereby, the photoresist resin composition 512 may be in direct contact with the entire inner surface of the nozzle 520.

[0130] The inside of the nozzle 520 can be maintained in a state filled with the photoresist resin composition 512. The state in which the photoresist resin composition 512 fills the inside of the nozzle 520 can be maintained for about 30 seconds to about 30 minutes. The state in which the photoresist resin composition 512 fills the inside of the nozzle 520 can be maintained for about 1 minute to about 30 minutes. The state in which the photoresist resin composition 512 fills the inside of the nozzle 520 can be maintained for about 2 minutes to about 30 minutes. The state in which the photoresist resin composition 512 fills the inside of the nozzle 520 can be maintained for about 3 minutes to about 30 minutes.

[0131] The photoresist resin composition 512 may be filled in a stopped state inside the nozzle 520. That is, the photoresist resin composition 512 may be filled inside the nozzle 520 with almost no flow.

[0132] Also, the photoresist resin composition 512 filled in the nozzle 520 may be in direct contact with the internal residue 513 of the nozzle 520. The photoresist resin composition 512 may be in direct contact with the residue 513 attached to the inside of the nozzle 520.

[0133] Thereby, the adhesion force between the residue 513 and the inner surface of the nozzle 520 can be reduced. Also, the residue can be detached from the inner surface of the nozzle 520. That is, until the residue 513 detaches from the inner surface of the nozzle 520, the state in which the photoresist resin composition 512 fills the inside of the nozzle 520 can be maintained.

[0134] The residue 513 may be foreign matter generated by hardening of the photoresist resin composition remaining in the previous process. That is, the residue 513 may be foreign matter other than the photoresist resin composition 512. Also, the residue 513 may be solid and the photoresist resin composition 512 may be liquid.

[0135] The residual matter 513 may have a refractive index different from that of the photoresist layer to be formed later.

[0136] Thereafter, as shown in FIG. 6, the photoresist resin composition 512 filled inside the nozzle 520 can be removed. That is, a certain amount of the photoresist resin composition 512 is ejected through the nozzle 520, and the residual matter 513 can be removed from the nozzle 520. That is, the detached residual matter can be removed together with the photoresist resin composition 512.

[0137] After the residual matter 512 detaches from the inner surface of the nozzle 520, it can be removed together with the ejected photoresist resin composition 512. Further, the residual matter 513 can be detached from the inner surface of the nozzle 520 by the injection pressure of the photoresist resin composition 512.

[0138] After the inner surface of the nozzle 520 is processed, the coating device can be provided.

[0139] Thereafter, 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 accommodating portion. The optical substrate 10 can be seated on the chuck 200.

[0140] The photoresist layer 50 on the optical substrate 10 is formed using the coating device.

[0141] To form the photoresist layer 50, the interior of the chamber 100 is isolated from the outside by the cover of the chamber 100. Then, with the chuck 200 rotating at high speed, the photoresist resin composition is dropped and coated on the upper surface of the optical substrate 10 by the supply unit 500 of the photoresist resin composition. Thus, a photoresist resin composition layer may be formed on the optical substrate 10.

[0142] At this time, the chuck 200 can rotate the optical substrate 10 by the following method.

[0143] First, the optical substrate 10 can go through a first rotation stage. The first rotation stage can be performed at a temperature of about 20°C to about 30°C. The first rotation stage may have a first rotation speed. The first rotation speed may be about 30 rpm to about 70 rpm. The first rotation stage can be performed for about 1 second to about 5 seconds.

[0144] Also, in the first rotation stage, the photoresist resin composition can be dropped onto the optical substrate 10. The dropping speed of the photoresist resin composition may be about 0.5 ml / second to about 5 ml / second.

[0145] After the first rotation stage, the optical substrate 10 can go through a second rotation stage. The second rotation stage can be performed at a temperature of about 20°C to about 30°C. The second rotation stage may have a second rotation speed. The second rotation speed may be about 50 rpm to about 100 rpm. The second rotation speed may be even greater than the speed of the first rotation stage. The second rotation stage can be performed for about 3 seconds to about 10 seconds.

[0146] After the second rotation stage, the optical substrate 10 can undergo a third rotation stage. The third rotation stage can be carried out at a temperature of about 20°C to about 30°C. The third rotation stage may have a third rotation speed. The third rotation speed may be about 100 rpm to about 150 rpm. The third rotation speed may be even greater than the second rotation speed. The third rotation stage can be carried out for about 5 seconds to about 13 seconds.

[0147] After the third rotation stage, the optical substrate 10 can undergo a fourth rotation stage. The fourth rotation stage can be carried out at a temperature of about 20°C to about 30°C. The fourth rotation stage may have a fourth rotation speed. The fourth rotation speed may be about 800 rpm to about 3000 rpm. The fourth rotation speed may be about 800 rpm to about 1500 rpm. The fourth rotation speed may be about 1500 rpm to about 2500 rpm. The fourth rotation speed may be about 2000 rpm to about 3000 rpm. The fourth rotation speed may be even higher than the third rotation speed. The fourth rotation speed may be about 500 rpm to about 2500 rpm higher than the third rotation speed. The fourth rotation stage can be carried out for about 0.5 seconds to about 2 seconds.

[0148] After the fourth rotation stage, the optical substrate 10 can undergo a fifth rotation stage. The fifth rotation stage can be carried out at a temperature of about 20°C to about 30°C. The fifth rotation stage may have a fifth rotation speed. The fifth rotation speed may be about 500 rpm to about 2500 rpm. The fifth rotation speed may be about 500 rpm to about 1200 rpm. The fifth rotation speed may be about 1000 rpm to about 2000 rpm. The fifth rotation speed may be about 1500 rpm to about 2500 rpm. The fifth rotation speed may be even lower than the fourth rotation speed. The fifth rotation speed may be about 300 rpm to about 1500 rpm lower than the fourth rotation speed. The fifth rotation stage can be carried out for about 1 second to about 5 seconds.

[0149] After the fifth rotation step, the optical substrate 10 can undergo a sixth rotation step. The sixth rotation step can be performed at a temperature of about 20°C to about 30°C. The sixth rotation step may have a sixth rotation speed. The sixth rotation speed may be about 100 rpm to about 500 rpm. The sixth rotation speed may be about 100 rpm to about 400 rpm. The sixth rotation speed may be about 100 rpm to about 300 rpm. The sixth rotation speed may be about 200 rpm to about 400 rpm. The sixth rotation step can be performed for about 30 seconds to about 60 seconds.

[0150] In the sixth rotation step, the photoresist resin composition layer formed on the optical substrate 10 can be dried to remove the solvent.

[0151] As a result, as shown in FIG. 7, the photoresist layer 50 may be formed on the optical substrate 10. Thereby, a blank mask including the optical substrate 10 and the photoresist layer 50 can be manufactured.

[0152] As shown in FIG. 8, the photoresist layer 50 may include a flat portion 51 and optical unevenness 52, 53.

[0153] The flat portion 51 may have a uniform thickness as a whole. Also, the flat portion 51 may have a thickness deviation of less than about 100 Å as a whole. The flat portion 51 may have a thickness deviation of less than about 90 Å as a whole. The flat portion 51 may have a thickness deviation of less than about 80 Å as a whole. The flat portion 51 may have a thickness deviation of less than about 50 Å as a whole. The thickness deviation may be the difference between the maximum thickness and the minimum thickness in the flat portion 51.

[0154] The thickness of the flat portion 51 can be measured by an ellipsometer. The thickness of the flat portion 51 can be measured by, for example, the SE MG series, SE MF series, SE MH series, or SE MI series of Nano-View.

[0155] The thickness of the flat portion 51 may be from about 1000 Å to about 10000 Å. The thickness of the flat portion 51 may be from about 1000 Å to about 5000 Å. The thickness of the flat portion 51 may be from about 1000 Å to about 4000 Å.

[0156] The optical irregularities 52 and 53 may have an optical thickness different from that of the flat portion 51. The optical thickness of the flat portion 51 can be derived by multiplying the refractive index of the flat portion 51 by twice the thickness of the flat portion 51. Also, the optical thickness of the optical irregularities 52 and 53 can be derived by multiplying the refractive index of the optical irregularities 52 and 53 by twice the thickness of the optical irregularities 52 and 53.

[0157] The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 5 nm. The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 10 nm. The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 15 nm. The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 20 nm. The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 30 nm. The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 40 nm. The difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 can exceed about 50 nm.

[0158] The maximum value of the difference between the optical thickness of the flat portion 51 and the optical thickness of the optical irregularities 52 and 53 may be about 500 nm.

[0159] The diameters of the optical unevennesses 52 and 53 can exceed about 10 nm. The diameters of the optical unevennesses 52 and 53 can exceed about 20 nm. The diameters of the optical unevennesses 52 and 53 can exceed about 30 nm. The diameters of the optical unevennesses 52 and 53 can exceed about 40 nm. The diameters of the optical unevennesses 52 and 53 can exceed about 50 nm. The diameters of the optical unevennesses 52 and 53 can exceed about 70 nm. The diameters of the optical unevennesses 52 and 53 can exceed about 100 nm.

[0160] The maximum value of the diameters of the optical unevennesses 52 and 53 may be about 500 nm.

[0161] Further, the optical unevennesses 52 and 53 may include a light path changing portion. The light path changing portion can change the path of incident light. Due to the light path changing portion, the path of the light incident on the optical unevennesses 52 and 53 is distorted, and the incident angle of the light and the reflection angle at the optical unevennesses 52 and 53 can be different from each other.

[0162] That is, for the light incident at the same angle, the reflection angle of the flat portion 51 and the reflection angle of the optical unevennesses 52 and 53 can be different from each other.

[0163] The optical unevennesses 52 and 53 may include a curved surface. The light path changing portion may include the curved surface of the optical unevennesses 52 and 53.

[0164] As shown in FIG. 8, the optical unevenness may include a first optical unevenness 52. The first optical unevenness 52 may be disposed in the photoresist layer 50. The first optical unevenness 52 may be disposed in a form immersed in the photoresist layer 50.

[0165] The first optical unevenness 52 may have a refractive index different from that of the flat portion 51. The difference between the refractive indices of the first optical unevennesses 52 and 53 and the refractive index of the flat portion 51 may be from about 0.05 to about 0.7. Thereby, the optical path can be changed at the boundary surface between the first optical unevenness 52 and the flat portion 51. That is, the reflection angle can be changed at the boundary surface between the first optical unevenness 52 and the flat portion 51.

[0166] That is, the optical path changing portion may include the boundary surface between the first optical unevenness 52 and the flat portion 51. That is, the optical path changing portion may include the curved surface of the first optical unevenness 52.

[0167] Further, the optical unevenness may include a second optical unevenness 53. The second optical unevenness 53 may protrude from the upper surface of the photoresist layer 50. That is, unevenness may be generated in the photoresist layer 50 by the second optical unevenness 53. That is, the height of the upper surface of the second optical unevenness 53 may be even higher than the height of the upper surface of the flat portion 51. The difference between the height of the upper surface of the second optical unevenness 53 and the height of the upper surface of the flat portion 51 may be from about 1 nm to about 100 nm.

[0168] Also, among the second optical unevennesses 53, the portion protruding from the upper surface of the photoresist layer 50 may have a curved surface. That is, the upper surface of the second optical unevenness 53 may protrude from the photoresist layer 50 and be a curved surface.

[0169] The optical path changing portion may include the curved surface of the second optical unevenness 53. The optical path changing portion may include the exposed upper surface of the second optical unevenness 53.

[0170] The optical unevennesses 52 and 53 can be detected by light of approximately 532 nm. The optical unevennesses 52 and 53 can be detected by a laser of approximately 532 nm. The laser irradiates the photoresist layer 50, and the optical unevennesses 52 and 53 can be detected by analyzing the light reflected from the photoresist layer 50.

[0171] After the photoresist layer 50 is irradiated with the laser, the reflected light can be sensed via an image sensor. The light reflected from the photoresist layer 50 can be sensed by the image sensor via a confocal and a spatial filter. Then, the signal sensed via the image sensor can be processed into an 8-bit 256-gray-scale image. The image can be processed at 640×480 pixels.

[0172] Also, when a difference exceeding approximately 3 gray levels occurs in the pixels of the image, the optical unevennesses 52 and 53 can be detected. When a difference exceeding approximately 5 gray levels occurs in the pixels of the image, the optical unevennesses 52 and 53 can be detected. When a difference exceeding approximately 7 gray levels occurs in the pixels of the image, the optical unevennesses 52 and 53 can be detected. When a difference exceeding approximately 10 gray levels occurs in the pixels of the image, the optical unevennesses 52 and 53 can be detected.

[0173] Also, the average area of the optical unevennesses 52 and 53 can be calculated based on the number of pixels detected for the optical unevennesses 52 and 53 in the image.

[0174] The optical unevennesses 52 and 53 can be detected by an optical surface inspection device. The optical unevennesses 52 and 53 can be detected by M6640S or M6641S of LASERTEC.

[0175] The number of the optical unevennesses 52 and 53 in the photoresist layer 50 is approximately 50 pieces / 36 inches. 2It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 40 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 30 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 20 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 10 pieces / 36 inches 2 It may also be less than.

[0176] The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 1 piece / 36 inches 2 ~ about 50 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 1 piece / 36 inches 2 ~ about 40 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 1 piece / 36 inches 2 ~ about 30 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 1 piece / 36 inches 2 ~ about 20 pieces / 36 inches 2 It may also be less than. The number of the optical irregularities 52 and 53 in the photoresist layer 50 is about 1 piece / 36 inches 2 ~ about 10 pieces / 36 inches 2 It may also be less than.

[0177] Since the photoresist layer 50 includes the optical irregularities 52 and 53 in the above-mentioned number, the photoresist layer 50 can be developed precisely. That is, since the photoresist layer 50 includes the optical irregularities 52 and 53 in the above-mentioned number, the precision in the exposure process of the photoresist layer 50 can be improved. Thereby, the method for manufacturing a blank mask according to the embodiment can provide a precise photomask.

[0178] Light selectively irradiates the photoresist layer 50, and the light-shielding film can be selectively etched to form a light-shielding pattern film 35. As a result, as shown in FIG. 9, a photomask 2 including the light-transmissive substrate 20 and the light-shielding pattern film 35 disposed on the light-transmissive substrate 20 can be formed.

[0179] The light-shielding pattern film 35 contains at least one of a transition metal, oxygen, and nitrogen.

[0180] The light-shielding pattern film 35 may be formed by patterning the light-shielding film 30 of the blank mask 100 described above.

[0181] Explanation regarding the physical properties, composition, structure, etc. of the light-shielding pattern film 35 is omitted because it overlaps with the explanation regarding the light-shielding film 30 of the blank mask 1.

[0182] The method for manufacturing a semiconductor device according to the embodiment includes a preparation step of disposing 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.

[0183] The photomask 2 includes a light-transmissive substrate 20 and a light-shielding pattern film 35 disposed on the light-transmissive substrate 20.

[0184] The light-shielding pattern film 35 contains at least one of a transition metal, oxygen, nitrogen, and carbon.

[0185] In the preparation step, the light source is a device capable of generating exposure light having a short wavelength. The exposure light may be light having a wavelength of 200 nm or less. The exposure light may be ArF light having a wavelength of 193 nm.

[0186] A lens may be further disposed between the photomask 2 and the semiconductor wafer. The lens has a function of reducing the shape of the circuit pattern on the photomask 2 and transferring it onto the semiconductor wafer. The lens is not limited as long as it can be generally applied to the exposure process of an ArF semiconductor wafer. As an example, a lens made of calcium fluoride (CaF2) can be applied as the lens.

[0187] In the exposure step, exposure light can be selectively transmitted onto the semiconductor wafer through the photomask 2. In such a case, chemical modification may occur in the portion of the resist film where the exposure light is incident.

[0188] In the development step, the semiconductor wafer after the exposure step can be treated with a developing solution to develop a pattern on the semiconductor wafer. When the applied resist film is a positive resist, the portion of the resist film where the exposure light is incident can be dissolved by the developing solution. When the applied resist film is a negative resist, the portion of the resist film where the exposure light is not incident can be dissolved by the developing solution. Through the developing solution treatment, the resist film is formed into a resist pattern. A pattern can be formed on the semiconductor wafer using the resist pattern as a mask.

[0189] The description of the photomask 2 is omitted because it overlaps with the above content.

[0190] The method for manufacturing a blank mask according to the embodiment includes a step of maintaining the photoresist composition filled inside the nozzle 520 that injects the photoresist composition. The method for manufacturing a blank mask according to the embodiment also includes a step of removing the photoresist composition inside the nozzle 520. Thereby, the residue adhering to the inside of the nozzle 520 can be easily removed.

[0191] As a result, the method for manufacturing a blank mask according to the embodiment can prevent the residue 513 from flowing into the photoresist layer 50.

[0192] As a result, the blank mask according to the embodiment can reduce the number of optical irregularities 52, 53 that may be caused by the residue or the like. The blank mask according to the embodiment may include the optical irregularities 52, 53 of less than 30 pieces / 36 inches. 2 even if it includes the optical irregularities 52, 53.

[0193] As a result, the method for manufacturing a blank mask according to the embodiment can realize a photoresist layer 50 having optical flatness as a whole. As a result, the photoresist layer 50 can precisely pattern the light-shielding film.

[0194] As a result, the blank mask according to the embodiment can provide a photomask having a precise pattern. The method for manufacturing a blank mask according to the embodiment includes a step of maintaining the inside of the nozzle 520 for injecting the photoresist resin composition filled with the photoresist resin composition. Further, the method for manufacturing a blank mask according to the embodiment includes a step of removing the photoresist resin composition inside the nozzle 520. As a result, the residue attached to the inside of the nozzle 520 can be easily removed.

[0195] As a result, the method for manufacturing a blank mask according to the embodiment can prevent the residue 513 from flowing into the photoresist layer 50.

[0196] As a result, the blank mask according to the embodiment can reduce the number of optical irregularities 52, 53 that may be caused by the residue 513 or the like. The blank mask according to the embodiment may include the optical irregularities 52, 53 of less than 30 pieces / 36 inches. 2 even if it includes the optical irregularities 52, 53.

[0197] Accordingly, the method for manufacturing a blank mask according to the embodiment can embody a photoresist layer 50 having overall optical flatness. Accordingly, the photoresist layer 50 can precisely pattern the light-shielding film.

[0198] Accordingly, the blank mask according to the embodiment can provide a photomask having a precise pattern.

[0199] Accordingly, the manufacturing apparatus for a blank mask according to the embodiment can minimize contamination of the blank mask manufactured by the above process by-products. In particular, the blank mask according to the embodiment can prevent the above process by-products from contaminating the side surface and the bottom surface of the optical substrate 10.

[0200] The manufacturing apparatus and the manufacturing method for a blank mask according to the embodiment can provide a blank mask having improved performance.

[0201] As described above, the preferred embodiments of the present invention have been described in detail. However, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the rights of the present invention.

[0202] Example 1 The resist coating was performed using an FEP171 (manufactured by FUJIFILM Arch Co, Ltd) solution (solid content: 8.5 wt%). FEP171 is a positron beam resist, and the solvent of the solution is a mixed solution of PGMEA (propylene glycol monomethyl ether acetate) and PGME (propylene glycol monomethyl ether) at a ratio of 8 to 2.

[0203] A quartz substrate having a size of about 6 inches × about 6 inches is used, and the quartz substrate has a thickness of 0.25 inches. A MoSiON film is formed on the quartz substrate by a sputtering process with a thickness of about 1000 Å. Then, the quartz substrate on which the MoSiON film is formed is fixed to a chuck.

[0204] Thereafter, the inside of the nozzle is filled with the FEP171 solution, and it is maintained for about 5 minutes with the FEP171 solution attached to the end of the nozzle. Then, the FEP171 solution in the nozzle is discharged and removed.

[0205] Thereafter, after the FEP171 solution is dropped onto the quartz substrate through the nozzle, the circumferential rotation speed changes stepwise at intervals of 250 rpm within the range of about 100 rpm to about 3000 rpm (5 conditions), and the circumferential rotation time changes stepwise at intervals of 1 second within the range of 1 second to 5 seconds (5 conditions). The drying rotation speed is fixed at 300 rpm, and the drying rotation is performed for about 40 seconds.

[0206] Thereby, an optical substrate on which a photoresist layer is formed is manufactured.

[0207] Examples 2 to 5 and Comparative Examples As shown in Table 1 below, the maintenance time of the solution attached in the nozzle was adjusted. For other processes, Example 1 is referred to.

[0208]

Table 1

[0209] Evaluation Examples 1. Number of optical irregularities In the optical substrates manufactured in the examples and comparative examples, the resist layer is irradiated with a laser having a wavelength of about 532 nm by an optical surface inspection equipment (M6641S of LASERTEC), and the reflected light is sensed, and the size and number of the optical irregularities are measured.

[0210] Laser Power: 0.06W Stage speed: 8.5 cm / sec

[0211] In the resist layer, the number of optical unevennesses detected by the surface inspection equipment was derived as shown in Table 2 below for each pixel size.

[0212] [Table 2]

[0213] As shown in Table 2, the photoresist layer according to the example contains optical unevennesses in a small number. [Explanation of Reference Numerals]

[0214] 10 Optical substrate 30 Light-shielding film 50 Photoresist layer 51 Flat part 52, 53 Optical unevenness

Claims

1. Forming a light-shielding film on a light-transmissive substrate to form an optical substrate; Preparing a nozzle for injecting a photoresist resin composition onto the optical substrate; Filling the nozzle with the photoresist resin composition and maintaining a state where the inside of the nozzle is filled with the photoresist resin composition; Removing the photoresist resin composition from inside the nozzle; Forming a photoresist layer on the light-shielding film using the nozzle; comprising; A method for manufacturing a blank mask.

2. The photoresist layer; A flat portion disposed on the light-shielding film; Optical unevenness having an optical thickness different from that of the flat portion; comprising; The optical unevenness is detected by a laser of 532 nm and arranged on the light-shielding film at less than 30 pieces / 36 inches. ２ ​ The method for manufacturing a blank mask according to Claim 1.

3. In the step of maintaining a state where the inside of the nozzle is filled with the photoresist resin composition, a part of the photoresist resin composition adheres so as to be exposed to the outside from the inlet of the nozzle; The method for manufacturing a blank mask according to Claim 1.

4. Maintained for about 30 seconds to about 300 minutes with the inside of the nozzle filled with the photoresist composition; The method for manufacturing a blank mask according to Claim 3.

5. In the step of maintaining a state where the inside of the nozzle is filled with the photoresist resin composition, residues adhering inside the nozzle detach from the inner surface of the nozzle; The method for manufacturing a blank mask according to Claim 4.

6. The step of maintaining a state where the inside of the nozzle is filled with the photoresist resin composition is maintained until the residues detach from the inner surface of the nozzle; The method for manufacturing a blank mask according to Claim 5.

7. The optical unevenness is less than 20 pieces / 36 inches ２ less than The method for manufacturing a blank mask according to Claim 2.

8. A transparent substrate; A light-shielding film disposed on the transparent substrate; A photoresist layer disposed on the light-shielding film; comprising; The photoresist layer; A flat portion disposed on the light-shielding film; Optical unevenness detected by a laser of 532 nm; comprising; The optical unevenness is arranged on the light-shielding film at less than 30 pieces / 36 inches. ２ and is A blank mask.

9. The optical unevenness is less than 20 pieces / 36 inches ２ less than The blank mask according to Claim 8.

10. The optical unevenness has a refractive index different from that of the photoresist layer; The blank mask according to Claim 8.

11. The optical unevenness has a thickness different from that of the photoresist layer; The blank mask according to Claim 8.

12. The optical unevenness has an optical thickness different from that of the flat portion. The blank mask according to claim 8. **Claim 13** The optical unevenness includes a light path changing portion. The blank mask according to claim 12. **Claim 14** The light path changing portion has a refractive index different from that of the flat portion. The blank mask according to claim 13.

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