Blank mask and method for manufacturing a 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 examples relate to a blank mask and a method for manufacturing a blank mask. [Background technology]

[0002] The increasing integration of semiconductor devices has led to a demand for miniaturization of circuit patterns in these devices. This has further emphasized the importance of lithography technology, which develops circuit patterns on the wafer surface using a photomask.

[0003] To develop miniaturized circuit patterns, the exposure light source used in the exposure process needs to have a shorter wavelength. In recent years, exposure light sources such as ArF excimer lasers (wavelength 193 nm) have been used.

[0004] On the other hand, 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 a binary mask, on the surface where the pattern is formed, the transparent areas without the light-shielding layer transmit exposure light, while the light-shielding areas with the light-shielding layer block the exposure light, thereby exposing the pattern onto the resist film on the wafer surface. However, as the pattern becomes finer, problems may arise in developing the fine pattern due to the diffraction of light generated at the edges of the transparent areas during the exposure process.

[0006] Phase shift masks include Levenson type, outrigger type, and half-tone type. Of these, the half-tone type phase shift mask has a configuration in which a pattern formed by a semi-transparent film is formed on a light-transmitting substrate 20. In the half-tone type phase shift mask, on the surface in which the pattern is formed, the transparent parts that do not contain the semi-transparent layer transmit exposure light, while the semi-transparent parts that contain the semi-transparent layer transmit attenuated exposure light. The attenuated exposure light has a phase difference compared to the exposure light that has passed through the transparent parts. As a result, the diffracted light generated at the edges of the transparent parts is canceled out by the exposure light that has passed through the semi-transparent parts, and the phase shift mask can form an even more intricate fine pattern on the wafer surface. [Prior art documents] [Patent Documents]

[0007] The relevant prior literature is as follows: [Patent Document 1] Republic of Korea Published Patent No. 10-2012-0057488 [Patent Document 2] Republic of Korea Published Patent No. 10-2014-0130420 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The embodiment aims to provide a blank mask and a method for manufacturing the same, which can be precisely patterned to provide a photomask with low optical distortion. [Means for solving the problem]

[0009] The method for manufacturing a blank mask according to the embodiment includes the steps of: forming a light-shielding film on a light-transmitting substrate to form an optical substrate; preparing a nozzle for spraying 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 inside the nozzle; and using the nozzle to form a photoresist layer on the light-shielding film.

[0010] In a method for manufacturing a blank mask according to one embodiment, the photoresist layer includes a flat portion disposed on the light-shielding film and optical irregularities having a different optical thickness from the flat portion, and the optical irregularities are detected by a 532 nm laser, with 30 / 232.26cm 2 It may be placed less than [a certain value].

[0011] In the method for manufacturing a blank mask according to one embodiment, during the step of maintaining the state in which the inside of the nozzle is filled with the photoresist resin composition, a portion of the photoresist resin composition may adhere to the nozzle so as to be exposed to the outside from the nozzle entrance.

[0012] In a method for manufacturing a blank mask according to one embodiment, the state in which the photorayst composition fills the inside of the nozzle can be maintained for about 30 seconds to about 300 minutes.

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

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

[0015] In a method for manufacturing a blank mask according to one embodiment, the optical irregularities are 20 pieces / 232.26cm 2 may be less than

[0016] A blank mask according to an 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, wherein the photoresist layer includes a flat portion disposed on the light-shielding film, the optical irregularities include optical irregularities detected by a 532 nm laser, and the optical irregularities are 30 pieces / on the light-shielding film 232.26cm 2 are arranged at a density less than

[0017] In a blank mask according to one embodiment, the optical irregularities are 20 pieces / 232.26cm 2 may be less than

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

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

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

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

[0022] In a blank mask according to one embodiment, the optical 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 the embodiment may include the steps of: forming a light-shielding film on a light-transmitting substrate to form an optical substrate; preparing a nozzle for spraying a photoresist resin composition onto the optical substrate; filling the nozzle with the photoresist resin composition and removing any residue from the inner surface of the nozzle; removing the photoresist resin composition and the removed residue from inside the nozzle; and using the nozzle to form a photoresist layer on the light-shielding film.

[0024] In the method for manufacturing a blank mask according to one embodiment, the residue can be attached to and detached from the photoresist resin composition filling the inside of the nozzle while adhering to the inner surface of the nozzle.

[0025] In a method for manufacturing a blank mask according to one embodiment, the state in which the photoresist resin composition fills the inside of the nozzle can be maintained for about 30 seconds to about 300 minutes.

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

[0027] In the method for manufacturing a blank mask according to one embodiment, the photoresist resin composition may be liquid, and the residue may be solid.

[0028] In a method for manufacturing a blank mask according to one embodiment, the optical surface is 20 / 232.26cm 2 It is acceptable to be less than [a certain value]. [Effects of the Invention]

[0029] The method for manufacturing a blank mask according to the examples includes a step of maintaining a state in which the inside of a nozzle for spraying the photoresist resin composition is filled with the photoresist resin composition. The method for manufacturing a blank mask according to the examples also includes a step of removing the photoresist resin composition from inside the nozzle. This makes it possible to easily remove any residue adhering to the inside of the nozzle.

[0030] As a result, the method for manufacturing a blank mask according to the examples can prevent the residue from flowing into the photoresist layer.

[0031] This allows the blank mask according to the example to reduce the number of optical irregularities that may be caused by the aforementioned residues, etc. The blank mask according to the example has 30 irregularities / 232.26cm 2 It may include the aforementioned optical irregularities if it is less than [a certain value].

[0032] As a result, the method for manufacturing a blank mask according to the embodiment can embody a photoresist layer that has optical flatness as a whole. This allows the photoresist layer to be precisely patterned with the light-shielding film.

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

[0034] As a result, the blank mask according to the example can provide a photomask with a precise pattern. [Brief explanation of the drawing]

[0035] [Figure 1] This is a cross-sectional view showing one cross-section of an optical substrate according to one embodiment. [Figure 2] This is a cross-sectional view showing one cross-section of an optical substrate according to another embodiment. [Figure 3]This is a cross-sectional view showing a cross-section of an optical substrate according to another embodiment. [Figure 4] This is a schematic diagram showing a blank mask manufacturing apparatus according to an example. [Figure 5] This diagram illustrates the process of removing residue adhering to the inside of the nozzle. [Figure 6] This diagram illustrates the process of removing residue adhering to the inside of the nozzle. [Figure 7] This is a cross-sectional view showing one cross-section of a blank mask according to the example. [Figure 8] This is a cross-sectional view showing an enlarged view of one cross-section of the blank mask according to the example. [Figure 9] This is a cross-sectional view showing one cross-section of a photomask according to one embodiment. [Modes for carrying out the invention]

[0036] The following descriptions detail embodiments so that they can be easily implemented by a person with ordinary skill in the art to which the embodiments belong. However, embodiments can be embodied in a variety of different forms and are not limited to the embodiments described herein.

[0037] Terms such as “approximately” and “substantially” as used herein are used to mean, in or near the numerical value of the tolerances for manufacture and material inherent to the meaning referred to, and are used to prevent unscrupulous infringers from unfairly exploiting disclosures that refer to precise or absolute numerical values ​​in order to understand the specific examples.

[0038] Throughout this specification, the term “these combinations” as used in a Markush expression means one or more mixtures or combinations selected from the group of components described in the Markush expression, and includes one or more selected from the group of components.

[0039] Throughout this specification, the phrase "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 between the same terms unless otherwise specified.

[0041] In this specification, the meaning of B being located on A means that B is located on A, or that B is located on A while other layers are located between them, and may be located on A, and is not limited to B being located in contact with the surface of A.

[0042] In this specification, singular expressions are to be interpreted as including singular or plural, as interpreted in the context, unless otherwise specified.

[0043] Figure 1 is a cross-sectional view showing a cross-section of an optical substrate according to one embodiment. Figure 2 is a cross-sectional view showing a cross-section of an optical substrate according to another embodiment. Figure 3 is a cross-sectional view showing a cross-section of an optical substrate according to yet another embodiment. Figure 4 is a schematic diagram showing a blank mask manufacturing apparatus according to an embodiment. Figures 5 and 6 show the process of removing residue adhering to the inside of the nozzle. Figure 7 is a cross-sectional view showing a cross-section of a blank mask according to an embodiment. Figure 8 is an enlarged cross-sectional view showing a cross-section of a blank mask according to an embodiment. Figure 9 is a cross-sectional view showing a cross-section of a photomask according to one embodiment.

[0044] The blank masks used in the examples may be manufactured by the following manufacturing process.

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

[0046] The light-transmitting substrate 20 may have light transmittance to exposure light. The light-transmitting substrate 20 may have a transmittance of more than 85% to exposure light with a wavelength of approximately 193 nm. The transmittance of the light-transmitting substrate 20 may be more than 87%. The transmittance of the light-transmitting substrate 10 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 the attenuation of transmitted light.

[0047] The light-transmitting substrate 20 has surface characteristics such as appropriate flatness and appropriate illuminance, so that distortion of transmitted light can be suppressed.

[0048] The light-shielding film 30 may be placed on the top surface of the light-transmitting substrate 20.

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

[0050] Furthermore, as shown in Figure 3, when a phase-shift film 40 or the like is placed 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 the process of etching the phase-shift film 40 or the like according to the pattern shape.

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

[0052] The light-shielding film 30 may contain chromium, oxygen, nitrogen, and carbon. The elemental content of the entire light-shielding film 30 may differ in the thickness direction. If the light-shielding film 30 consists of multiple layers, the elemental content may differ for each layer.

[0053] The light-shielding film 30 may contain chromium in an amount of approximately 44 atom% to approximately 60 atom%. The light-shielding film 30 may contain chromium in an amount of approximately 47 atom% to approximately 57 atom%.

[0054] The light-shielding film 30 may contain carbon in an amount of approximately 5 atom% to 30 atom%. The light-shielding film 30 may contain carbon in an amount of approximately 7 atom% to approximately 25 atom%.

[0055] The light-shielding film 30 may contain nitrogen in an amount of approximately 3 atom% to approximately 20 atom%. The light-shielding film 30 may contain nitrogen in an amount of approximately 5 atom% to approximately 15 atom%.

[0056] The light-shielding film 30 may contain oxygen in an amount of approximately 20 atom% to approximately 45 atom%. The light-shielding film 30 may contain oxygen in an amount of approximately 25 atom% to approximately 40 atom%.

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

[0058] As shown in Figure 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. The second light-shielding layer 32 may also 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 at least one element corresponding to oxygen, nitrogen, or carbon in the second light-shielding layer 32 may be about 10 atom% to about 35 atom%. The content of at least one element corresponding to oxygen, nitrogen, or carbon in the second light-shielding layer 32 may be about 15 atom% to about 25 atom%.

[0061] The second light-shielding layer 32 may contain nitrogen in an amount of approximately 5 atom% to approximately 20 atom%. The second light-shielding layer 32 may contain nitrogen in an amount of approximately 7 atom% to approximately 13 atom%.

[0062] The second light-shielding layer 32 may contain oxygen in an amount of approximately 5 atom% to approximately 20 atom%. The second light-shielding layer 32 may contain oxygen in an amount of approximately 7 atom% to approximately 13 atom%.

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

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

[0065] In such a case, the light-shielding film 30 can form a laminate together with the phase-shift film 40, thereby assisting in substantially blocking 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% to 60 atom%. The light-shielding layer 21 may contain a transition metal in an amount of 35 atom% to 55 atom%. The first light-shielding layer 31 may contain a transition metal in an amount of 40 atom% to 50 atom%.

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

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

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

[0070] In such a case, the first light-shielding layer 31 can help the light-shielding film 30 to have excellent quenching properties.

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

[0072] The thickness of the first light-shielding layer 31 may be approximately 250 Å to approximately 650 Å. The thickness of the first light-shielding layer 31 may be approximately 350 Å to approximately 600 Å. The thickness of the first light-shielding layer 31 may be approximately 400 Å to approximately 550 Å. In such cases, the first light-shielding layer 31 can assist the light-shielding film 30 in effectively blocking 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 to about 100 Å. The thickness of the second light-shielding layer 32 may be about 40 Å to about 80 Å. In such cases, the second light-shielding layer 32 can improve the quenching characteristics of the light-shielding film 30 and help to further refine the surface profile of the side surface of the light-shielding pattern film 35 formed during the 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 thickness of 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 thickness of 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 quenching properties, and the surface profile of the side surface of the light-shielding pattern film 35 formed during the patterning of the light-shielding film 30 can be controlled with even greater precision.

[0076] The transition metal content of the second light-shielding layer 32 may be even greater than the transition metal content of the first light-shielding layer 31.

[0077] To further refine the surface profile of the side surface 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 inspection light in defect inspection is at a value suitable for inspection, the second light-shielding layer 32 may be required to have a higher transition metal content than the first light-shielding layer 31.

[0078] However, in such a case, during the heat treatment process 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. If grain growth occurs in the second light-shielding layer 32, which contains a high content of transition metal, the surface illuminance characteristics of the light-shielding film 30 may fluctuate excessively due to the overgrown transition metal particles. This can increase the number of false defects detected when inspecting the surface of the light-shielding film 30 for defects with high sensitivity.

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

[0080] The light-shielding film 30 may have an optical density of approximately 1.8 to approximately 3. The light-shielding film 30 may have an optical density of approximately 1.9 to approximately 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 Figure 3, the optical substrate 10 may further include a phase-shift film 40.

[0083] The phase-shift film 40 may be placed 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 to adjust the phase difference and substantially suppresses diffracted light generated at the edges of the pattern.

[0084] The phase-shift film 40 may have a phase difference of approximately 170° to approximately 190° with respect to light with a wavelength of 193 nm. The phase-shift film 40 may have a phase difference of approximately 175° to approximately 185° with respect to light with a wavelength of 193 nm.

[0085] The phase-shift film 40 may have a transmittance of approximately 3% to approximately 10% for light with a wavelength of 193 nm. The phase-shift film 40 may have a transmittance of approximately 4% to approximately 8% for light with a wavelength of 193 nm. In such cases, the resolution of the photomask 200 containing 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 positioned on the light-shielding film 30. The hard mask can act 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 the step of forming the light-shielding film 30 on the light-transmitting 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 carried out.

[0090] The aforementioned heat treatment step can be carried out at a temperature of approximately 200°C to approximately 400°C.

[0091] The aforementioned heat treatment step can be carried out for approximately 5 to 30 minutes.

[0092] Furthermore, 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 step.

[0093] The sputtering target can be selected considering 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 include one 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 also include Cr.

[0095] The aforementioned 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 that constitute the deposited thin film. The reactive gas is a gas that contains the elements that constitute the deposited 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 contain helium.

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

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

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

[0100] The sputtering gas may be Ar gas.

[0101] The power supply used to apply power to the sputtering target can be a DC power supply or an RF power supply.

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

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

[0104] The rinsing step includes a step of treating the light-shielding film 30 with a cleaning solution. The cleaning solution may contain at least one of deionized water, hydrogen water, ozonated water, or carbonated water. The cleaning solution may also contain carbonated water.

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

[0106] The chamber 100 houses the chuck 200. The chamber 100 can house an optical substrate 10 for manufacturing a blank mask. The chamber 100 can be isolated from the outside. The inside of the chamber 100 can be sealed. The internal pressure of the chamber 100 can be a vacuum lower than atmospheric pressure.

[0107] Furthermore, the chamber 100 may include a door or cover that can be opened and closed. The chamber 100 may also be equipped with a heater or the like that can adjust 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 positioned 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 formed integrally with the support portion 210. The guide portion may be positioned 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 housing portion for housing the optical substrate 10. That is, the support portion may be positioned on the lower surface of the optical substrate 10, and the guide portion may be positioned on the side surface of the optical substrate 10 to constitute the housing portion.

[0113] The housing portion can correspond to the planar shape of the optical substrate 10. The planar shape of the housing 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 square, and the planar shape of the housing portion may also be square.

[0114] The outer casing of the guide portion may be circular in shape. The guide portion and the support portion may both be circular in shape.

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

[0116] The photoresist resin composition supply unit 500 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 located within the chamber 100. The photoresist resin composition 510 can be dropped onto the optical substrate 10 via the injection nozzle 520. In other words, the photoresist resin composition supply unit 500 can spray 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 or radiation-sensitive resin composition. The photoresist composition is a resist composition for negative-type pattern formation and may be a negative-type resist composition for organic solvent development or a negative-type resist composition for alkaline development. The photoresist resin composition may typically be a chemically amplified resist composition.

[0118] The aforementioned photoresist resin composition may contain a binder resin, a photosensitive agent, and an organic solvent.

[0119] Examples of the binder resin include novolac resin, phenolic resin, epoxy resin, or polyimide resin. Examples of the binder resin include polyvinyl pyrolidone or poly(acrylamide-co-diacetoneacrylamide).

[0120] In the example of the photosensitive agent, at least one can be selected from the group consisting of 4,4'-diazido-2,2'-stilbendisulfonate sodium salt, 4,4'-diazo-2,2'-dibenzalacetone disodium salt, 2,5-bis(4-azido-2-sulfobenzylidene)cyclopentanone disodium salt, or 4,4'-diazido-2,2'-stilbendisulfonate sodium salt (DACA).

[0121] The aforementioned solvents include ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethyl ethyl 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 cyclohexyl At least one can be selected from the group consisting of sanone, 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 solid content of the photoresist resin composition, excluding the solvent, may be about 3 wt% to about 20 wt% based on the total weight. The solid content of the photoresist resin composition, excluding the solvent, may be about 3 wt% to about 15 wt% based on the total weight. The solid content of the photoresist resin composition, excluding the solvent, 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 an amount of approximately 2 wt% to approximately 50 wt% based on the total weight. The photoresist resin composition may also contain the binder resin in an amount of approximately 3 wt% to approximately 15 wt%.

[0124] The photoresist composition may contain the photosensitive agent in an amount of about 0.5 wt% to about 40 wt%. The photoresist composition may contain the photosensitive agent in an amount of about 0.5 wt% to about 20 wt%. The photoresist composition may contain the photosensitive agent in an amount of about 0.5 wt% to about 10 wt%. The photoresist composition may contain the photosensitive agent in an amount 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 aforementioned photoresist resin composition may further contain additives such as labeling agents or adhesion aids.

[0127] As shown in Figures 5 and 6, the coating apparatus can be operated in order to form the photoresist layer 50 on the optical substrate 10.

[0128] First, the inside of the nozzle 520 of the coating apparatus can be treated in the following manner.

[0129] As shown in Figure 5, the inside of the nozzle 520 is filled with the photoresist resin composition 512. The inside of the nozzle 520 may be completely filled with the photoresist resin composition 512. In addition, a portion 511 of the photoresist resin composition may adhere to the entrance of the nozzle 520. As a result, the entire inner surface of the nozzle 520 may be in direct contact with the photoresist resin composition 512.

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

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

[0132] Furthermore, the photoresist resin composition 512 filling 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 adhering to the inside of the nozzle 520.

[0133] This can reduce the adhesion between the residue 513 and the inner surface of the nozzle 520. Furthermore, the residue can detach from the inner surface of the nozzle 520. In other words, the photoresist resin composition 512 can remain filled inside the nozzle 520 until the residue 513 detaches from the inner surface of the nozzle 520.

[0134] The residue 513 may be foreign matter generated from hardened photoresist resin composition remaining from a previous process. In other words, the residue 513 may be foreign matter other than the photoresist resin composition 512. Furthermore, the residue 513 may be solid, while the photoresist resin composition 512 may be liquid.

[0135] The residue 513 may have a refractive index different from that of the photoresist layer formed thereafter.

[0136] Subsequently, as shown in Figure 6, the photoresist resin composition 512 filling the inside of the nozzle 520 can be removed. That is, a certain amount of photoresist resin composition 512 is ejected through the nozzle 520, and the residue 513 can be removed from the nozzle 520. In other words, the detached residue can be removed together with the photoresist resin composition 512.

[0137] The residue 512 can be removed together with the sprayed photoresist resin composition 512 after it has detached from the inner surface of the nozzle 520. The residue 513 can also be detached from the inner surface of the nozzle 520 by the spraying pressure of the photoresist resin composition 512.

[0138] After the inner surface of the nozzle 520 has been treated, the coating apparatus can be installed.

[0139] Subsequently, the optical substrate 10 may be placed inside the chamber 100. The optical substrate 10 may be temporarily fixed to the chuck 200. The optical substrate 10 may be placed inside the housing. The optical substrate 10 can be securely attached to the chuck 200.

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

[0141] In order for the photoresist layer 50 to be formed, the inside 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 onto the upper surface of the optical substrate 10 by the photoresist resin composition supply unit 500. This may form a photoresist resin composition layer on the optical substrate 10.

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

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

[0144] Furthermore, during the first rotation stage, the photoresist resin composition may be dropped onto the optical substrate 10. The dropping rate of the photoresist resin composition may be approximately 0.5 ml / second to approximately 5 ml / second.

[0145] The optical substrate 10 may undergo a second rotation stage after the first rotation stage. The second rotation stage can be performed at a temperature of approximately 20°C to approximately 30°C. The second rotation stage may have a second rotation speed. The second rotation speed may be approximately 50 rpm to approximately 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 approximately 3 seconds to approximately 10 seconds.

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

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

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

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

[0150] During the six rotation steps, the photoresist resin composition layer formed on the optical substrate 10 dries, and the solvent can be removed.

[0151] As a result, the photoresist layer 50 may be formed on the optical substrate 10, as shown in Figure 7. This makes it possible to manufacture a blank mask including the optical substrate 10 and the photoresist layer 50.

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

[0153] The flat portion 51 may have a uniform thickness overall. Alternatively, the flat portion 51 may have a thickness deviation of less than approximately 100 Å overall. The flat portion 51 may have a thickness deviation of less than approximately 90 Å overall. The flat portion 51 may have a thickness deviation of less than approximately 80 Å overall. The flat portion 51 may have a thickness deviation of less than approximately 50 Å overall. The thickness deviation may be the difference between the maximum thickness and the minimum thickness of the flat portion 51.

[0154] The thickness of the flat portion 51 can be measured using a spectroscopic ellipsometer. The thickness of the flat portion 51 can be measured using Nano-View's SE MG series, SE MF series, SE MH series, or SE MI series, etc.

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

[0156] The optical irregularities 52 and 53 may have different optical thicknesses than the flat portion 51. The optical thickness of the flat portion 51 can be derived from the refractive index of the flat portion 51 and twice the thickness of the flat portion 51. Also, the optical thickness of the optical irregularities 52 and 53 can be derived from the refractive index of the optical irregularities 52 and 53 and 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 approximately 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 approximately 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 approximately 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 approximately 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 approximately 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 approximately 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 approximately 50 nm.

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

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

[0160] The maximum diameter of the optical irregularities 52 and 53 may be approximately 500 nm.

[0161] Furthermore, the optical irregularities 52, 53 may include an optical path changing section. The optical path changing section can change the path of the incident light. The optical path changing section distorts the path of the light incident on the optical irregularities 52, 53, and the angle of incidence of the light and the angle of reflection at the optical irregularities 52, 53 may differ from each other.

[0162] In other words, for light incident at the same angle, the reflection angle of the flat portion 51 and the reflection angles of the optical irregularities 52 and 53 can be different from each other.

[0163] The optical irregularities 52, 53 may include curved surfaces. The optical path changing portion may include the curved surfaces of the optical irregularities 52, 53.

[0164] As shown in Figure 8, the optical surface may include a first optical surface 52. The first optical surface 52 may be arranged within the photoresist layer 50. The first optical surface 52 may be arranged in a form immersed within the photoresist layer 50.

[0165] The first optical surface 52 may have a different refractive index than the flat portion 51. The difference between the refractive index of the first optical surface 52, 53 and the refractive index of the flat portion 51 may be about 0.05 to about 0.7. This can change the optical path at the interface between the first optical surface 52 and the flat portion 51. In other words, the reflection angle can be changed at the interface between the first optical surface 52 and the flat portion 51.

[0166] In other words, the optical path changing portion may include the interface between the first optical irregularities 52 and the flat portion 51. In other words, the optical path changing portion may include the curved surface of the first optical irregularities 52.

[0167] Furthermore, the optical irregularities may include a second optical irregularity 53. The second optical irregularity 53 may protrude from the upper surface of the photoresist layer 50. That is, the second optical irregularity 53 may cause irregularities to be generated in the photoresist layer 50. In other words, the height of the upper surface of the second optical irregularity 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 irregularity 53 and the height of the upper surface of the flat portion 51 may be about 1 nm to about 100 nm.

[0168] Furthermore, the portion of the second optical surface 53 that protrudes from the upper surface of the photoresist layer 50 may have a curved surface. That is, the upper surface of the second optical surface 53 may protrude from the photoresist layer 50 and have a curved surface.

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

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

[0171] After the laser irradiates the photoresist layer 50, 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. Subsequently, the signal sensed by the image sensor can be processed into an 8-beat, 256-level grayscale image. The image can be processed at 640 x 480 pixels.

[0172] Furthermore, when a difference exceeding approximately 3 tones occurs in the pixels of the image, it can be detected by the optical surface irregularities 52, 53. When a difference exceeding approximately 5 tones occurs in the pixels of the image, it can be detected by the optical surface irregularities 52, 53. When a difference exceeding approximately 7 tones occurs in the pixels of the image, it can be detected by the optical surface irregularities 52, 53. When a difference exceeding approximately 10 tones occurs in the pixels of the image, it can be detected by the optical surface irregularities 52, 53.

[0173] Furthermore, the average area of ​​the optical surface irregularities 52 and 53 can be calculated based on the number of pixels detected in the optical surface irregularities 52 and 53 in the image.

[0174] The optical irregularities 52, 53 can be detected by optical surface inspection equipment. The optical irregularities 52, 53 can be detected by LASERTEC's M6640S or M6641S.

[0175] The number of optical irregularities 52, 53 in the photoresist layer 50 is approximately 50 / 232.26cm2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 40 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 30 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 20 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 10 / 232.26cm 2 may be less.

[0176] The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 1 / 232.26cm 2 to about 50 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 1 / 232.26cm 2 ~ about 40 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 1 / 232.26cm 2 to about 30 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 1 / 232.26cm 2 to about 20 / 232.26cm 2 may be less. The number of said optical irregularities 52, 53 in said photoresist layer 50 is about 1 / 232.26cm 2 to about 10 / 232.26cm 2 may be less.

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

[0178] When light is selectively irradiated onto the photoresist layer 50, the light-shielding film is selectively etched to form a light-shielding pattern film 35. This makes it possible to form a photomask 2 including the light-transmitting substrate 20 and the light-shielding pattern film 35 disposed on the light-transmitting substrate 20, as shown in Figure 9.

[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] The description of the physical properties, composition, and structure of the light-shielding pattern film 35 is omitted because it overlaps with the description of 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 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.

[0183] The photomask 2 includes a light-transmitting substrate 20 and a light-shielding pattern film 35 disposed on the light-transmitting 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 stage described above, the light source is a device capable of generating short-wavelength exposure light. The exposure light may have a wavelength of 200 nm or less. The exposure light may also be ArF light with a wavelength of 193 nm.

[0186] A lens may be further placed between the photomask 2 and the semiconductor wafer. The lens has the 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 ArF semiconductor wafers. For example, the lens may be made of calcium fluoride (CaF2).

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

[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. If the coated resist film is a positive resist, the portion of the resist film that has been exposed to light can be dissolved by the developing solution. If the coated resist film is a negative resist, the portion of the resist film that has not been exposed to light can be dissolved by the developing solution. The developing solution treatment forms a resist pattern in the resist film. The resist pattern can then be used as a mask to form a pattern on the semiconductor wafer.

[0189] The explanation regarding the aforementioned photomask 2 is omitted as it overlaps with the content above.

[0190] The method for manufacturing a blank mask according to the example includes the step of maintaining a state in which the inside of the nozzle 520, which sprays the photoresist composition, is filled with the photoresist composition. The method for manufacturing a blank mask according to the example also includes the step of removing the photoresist composition from inside the nozzle 520. This makes it possible to easily remove any residue adhering to the inside of the nozzle 520.

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

[0192] This allows the blank mask according to the embodiment to reduce the number of optical irregularities 52, 53 that may be caused by the aforementioned residues, etc. The blank mask according to the embodiment has 30 irregularities / 232.26cm 2 It may also include the optical irregularities 52, 53 if it is less than the specified value.

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

[0194] As a result, the blank mask according to the embodiment can provide a photomask with a precise pattern. The method for manufacturing the blank mask according to the embodiment includes the step of maintaining a state in which the photoresist resin composition is filled inside the nozzle 520 that sprays the photoresist resin composition. The method for manufacturing the blank mask according to the embodiment also includes the step of removing the photoresist resin composition from inside the nozzle 520. As a result, any residue adhering 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 example can prevent the residue 513 from flowing into the photoresist layer 50.

[0196] This allows the blank mask according to the embodiment to reduce the number of optical irregularities 52, 53 that may be caused by the residue 513, etc. The blank mask according to the embodiment has 30 irregularities / 232.26cm 2 It may also include the optical irregularities 52, 53 if it is less than the specified value.

[0197] As a result, the method for manufacturing a blank mask according to the embodiment can embody a photoresist layer 50 that has optical flatness as a whole. This allows the photoresist layer 50 to precisely pattern the light-shielding film.

[0198] As a result, the blank mask according to the example can provide a photomask with a precise pattern.

[0199] As a result, the blank mask manufacturing apparatus according to the embodiment can minimize contamination of the blank mask produced by the above-mentioned process by-products. In particular, the blank mask according to the embodiment can prevent the above-mentioned process by-products from contaminating the sides and bottom surface of the optical substrate 10.

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

[0201] As described above, preferred embodiments of the present invention have been explained in detail, but the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art, utilizing the basic concepts of the present invention as defined in the following claims, also fall within the scope of the present invention.

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

[0203] A quartz substrate measuring approximately 6 inches x 6 inches was used, and the quartz substrate had a thickness of 0.25 inches. A MoSiON film was formed on the quartz substrate to a thickness of approximately 1000 Å by a sputtering process. Subsequently, the quartz substrate on which the MoSiON film was formed was fixed to a chuck.

[0204] Subsequently, the inside of the nozzle was filled with the FEP171 solution, and the FEP171 solution remained in contact with the end of the nozzle for approximately 5 minutes. After that, the FEP171 solution inside the nozzle was discharged and removed.

[0205] Subsequently, after the FEP171 solution was dripped onto the quartz substrate via the nozzle, the rotational speed was stepped in increments of 250 rpm (5 conditions) within the range of approximately 100 rpm to approximately 3000 rpm, and the rotational time was stepped in increments of 1 second (5 conditions) within the range of 1 second to 5 seconds. The drying rotational speed was fixed at 300 rpm, and the drying rotation was performed for approximately 40 seconds.

[0206] This resulted in the manufacture of an optical substrate on which a photoresist layer was formed.

[0207] Examples 2-5 and Comparative Examples As shown in Table 1 below, the retention time of the solution inside the nozzle was adjusted. Other steps refer to Example 1.

[0208] [Table 1]

[0209] Evaluation example 1. Number of optical surface irregularities In the optical substrates manufactured in the examples and comparative examples, the resist layer is irradiated with a laser having a wavelength of approximately 532 nm using optical surface inspection equipment (LASERTEC's M6641S), and the reflected light is sensed to measure the size and number of optical irregularities.

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

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

[0212] [Table 2]

[0213] As shown in Table 2, the photoresist layer in the examples contains optical irregularities with a small number of particles. [Explanation of Symbols]

[0214] 10 Optical board 30 Light-shielding film 50 Photoresist Layers 51 Flat area 52,53 Optical unevenness

Claims

1. The steps include forming a light-shielding film on a light-transmitting substrate to form an optical substrate, The steps include preparing a nozzle for spraying a photoresist resin composition onto the optical substrate, The steps include filling the nozzle with the photoresist resin composition and maintaining the state in which the inside of the nozzle is filled with the photoresist resin composition, A step of spraying a certain amount of the photoresist resin composition through the nozzle and removing the photoresist resin composition from inside the nozzle, The steps include forming a photoresist layer on the light-shielding film using the nozzle, Includes, The nozzle is filled with the photoresist resin composition and maintained for 30 seconds to 300 minutes. In the step of maintaining the state in which the inside of the nozzle is filled with the photoresist resin composition, any residue adhering to the inside of the nozzle is removed from the inner surface of the nozzle. A method for manufacturing blank masks.

2. The aforementioned photoresist layer is A flat portion disposed on the light-shielding film, Optical irregularities having an optical thickness different from the flat portion, Includes, The optical irregularities are detected by a 532 nm laser and arranged on the light-shielding film at a density of less than 30 per 232.26 cm². A method for manufacturing a blank mask according to claim 1.

3. In the step of maintaining the state in which the inside of the nozzle is filled with the photoresist resin composition, A portion of the photoresist resin composition is attached so as to be exposed to the outside from the nozzle entrance. A method for manufacturing a blank mask according to claim 1.

4. The step of maintaining the state in which the inside of the nozzle is filled with the photoresist resin composition is maintained until the residue is detached from the inner surface of the nozzle. A method for manufacturing a blank mask according to claim 1.

5. The optical surface features are less than 20 per 232.26 cm². A method for manufacturing a blank mask according to claim 2.

Images