Method for producing resist

Abstract

To provide a method for producing a resist controlled in defects in liquid.SOLUTION: A method for producing a resist includes: a process of repeating a process of mixing raw materials of a resist in a tank to obtain a resist mixture, a process of sending the resist mixture to an inlet of a filter having the inlet and an outlet from a lower part of the tank, a process of filtering the resist mixture by using the filter, and a process of sending the filtered resist mixture to the tank; a process of mixing a resist mixture obtained from between the lower part and the inlet with a predetermined chemical liquid to obtain a first mixture; a process of measuring a first liquid defect in the first mixture; a process of mixing a resist mixture obtained from between the outlet and the tank with a predetermined chemical liquid to obtain a second mixture; a process of measuring a defect in the second liquid of the second mixture; and a process of comparing the defect in the first liquid with the defect in the second liquid.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a resist manufacturing method, and more specifically to a resist manufacturing method in which in-liquid defects are controlled in a resist liquid in which a high molecular weight polymer resin is dissolved, and a method for measuring in-liquid defects in such a resist liquid. [Background technology]

[0002] Various liquids (chemicals) are used in the semiconductor device manufacturing process. In particular, the resist (photoresist) used in the lithography process contains liquid defects such as bubbles, metal particles, and other particles. The presence of liquid defects causes various problems during the patterning process (resist coating, light exposure, and development), leading to defective device shapes during the fine processing of semiconductor devices. This results in reduced semiconductor device yields. Therefore, liquid defects are removed during the resist manufacturing process (mixing resist resin, additives, solvents, photosensitizers, etc., and filling resist into shipping containers) at resist manufacturers and during the patterning process at device manufacturers—specifically, the resist coating process (spin coating equipment) on semiconductor wafers—by passing the resist through a liquid filter for purification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-31835 [Patent Document 2] Patent No. 6549747 [Patent Document 3] Patent No. 6687951 [Non-Patent Document 1] Fujii Shuji, Surface Technology 59(1), 33-38, 2008 "Foam stabilized by fine particles" [Non-patent document 2] Tabuchi Takuya, “Real Time Measurement of Exact Size and Refractive Index of Particles in Liquid by Flow Particle Tracking Method”, IEEE Transactions on Semiconductor Manufacturing PP(99)1-1. Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the embodiments is to provide a method for manufacturing a resist in which in-liquid defects are controlled. [Means for solving the problem]

[0005] The resist manufacturing method of the embodiment includes the steps of: obtaining a resist mixture by mixing resist raw materials in a tank; sending the resist mixture from the bottom of the tank to the inlet of a filter having an inlet and an outlet; filtering the resist mixture using the filter; and sending the filtered resist mixture from the outlet to the tank; obtaining a first mixture by mixing the resist mixture obtained from between the bottom and the inlet with a predetermined chemical liquid; measuring defects in the first liquid of the first mixture; obtaining a second mixture by mixing the resist mixture obtained from between the outlet and the tank with a predetermined chemical liquid; measuring defects in the second liquid of the second mixture; and comparing the defects in the first liquid with the defects in the second liquid.

[0006] For example, in one embodiment, a measurement method involves placing a mixture (resist) primarily composed of an organic solvent, a polymer resin, a photosensitizer, and additives in a mixing container, stirring and mixing these components in a mixer installed inside the container, and then operating a circulation system consisting of a liquid suction / discharge pump connected to a pipe that extracts the mixture from the bottom of the mixing container, and a pipe connected to a downstream stage of the pump that returns the "filtrate" of the mixture to the mixing container after passing through various filters. The circulation pump is then operated for a certain period of time to identify defects during filtration of the mixture and perform appropriate circulation and filtration, thereby reducing defects caused by foreign matter in the resist liquid and achieving stable quality. The defect types and number of defects in the resist mixture sampled from points α and β downstream of the circulation pump, before passing through the filter, and after passing through the filter, are measured. Both the α and β liquids contain organic molecular components such as the polymer resin, the photosensitizer, and additives, as well as impurities such as metal particles, bubbles, and non-metallic defect particles. Therefore, cluster defects resulting from aggregation of organic components and impurities are present. Therefore, an appropriate amount of chemical solution X, which can dissolve cluster defects, is added to each of the α and β solutions to dissolve the cluster defects, and the α+X and β+X solutions are measured using FPT to identify the defects present in each solution. FPT measurement is a method that can separately measure "metal particles A" and "bubbles B and particles D that are different from metal particles A." By measuring the α+X and β+X solutions, in which chemical solution X has been added to the α and β solutions sampled at both defect measurement points α and β, using FPT, defect measurement and defect control in the resist solution during the resist manufacturing process are carried out. [Brief explanation of the drawings]

[0007] [Figure 1] 10A and 10B are schematic diagrams illustrating the behavior of light scattering from a light scatterer in a resist liquid in a comparative example of a method for measuring in-liquid defects in a resist liquid. [Figure 2] 1A to 1C are schematic diagrams illustrating a resist manufacturing method according to a first embodiment. [Figure 3] 3A to 3C are schematic diagrams illustrating a method for measuring defects in a resist liquid according to the first embodiment. [Figure 4] FIG. 2 is a schematic diagram of a defect detection cell according to the first embodiment. [Figure 5] 1 is an example of a liquid evaluation including submerged defects, performed using the defect detection cell of the first embodiment. [Figure 6] 10 is another example of a liquid evaluation including a liquid-submerged defect, performed using the defect detection cell of the first embodiment. [Figure 7] 10 is another example of a liquid evaluation including submerged defects, performed using the defect detection cell of the first embodiment. [Figure 8] 4 is a diagram illustrating the background scattered light intensity that changes depending on the ratio of the chemical solution X added to the resist solution of the first embodiment. FIG. [Figure 9] 10 is an example showing the circulation time dependency of the number of filter secondary defects in the resist liquid in the first embodiment (in the case of a monotonically decreasing phenomenon of filter secondary defects in the resist liquid). [Figure 10] 10 is an example showing the circulation time dependence of the number of secondary defects in the filter of defects (metal particle defects A) in the resist liquid in the first embodiment (when the decrease in the number of metal particle defects A in the secondary liquid of the filter stops midway and the number of defects reaches saturation). [Figure 11] 10 is an example showing the circulation time dependency of the number of defects (bubbles B, and the total number of bubbles B, metal particles A, and particles D different from bubbles B) in the filter secondary resist liquid of the first embodiment. [Figure 12] This is the dependency of the mixing ratio of the resist mixture and the specified chemical solution X, measured by the FPT method. [Figure 13] 10A to 10C are schematic diagrams illustrating a method for measuring defects in a resist liquid according to a second embodiment. [Figure 14] 10 is an example of a liquid evaluation including submerged defects, performed using the defect detection cell of the second embodiment. [Figure 15] 10 is an example of a liquid evaluation including submerged defects, performed using the second submerged defect measuring instrument 318 of the second embodiment. [Figure 16] 10A to 10C are schematic diagrams illustrating a method for measuring defects in a resist liquid in another aspect of the second embodiment. [Figure 17] 10A to 10C are schematic diagrams illustrating a resist manufacturing method according to a third embodiment. [Figure 18]10A to 10C are schematic diagrams illustrating a resist manufacturing method according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described with reference to the drawings. In the drawings, the same or similar parts are denoted by the same or similar reference numerals.

[0009] (First embodiment) To explain the first embodiment, a comparative embodiment will be shown first.

[0010] First, a comparative resist manufacturing method will be described. Here, a method for evaluating defects in a resist liquid used in the resist manufacturing method will be described. This method for evaluating defects in a resist liquid is a method for evaluating the presence or absence of defects in a resist liquid as the presence or absence of light scatterers using a light scattering method (liquid particle counter: LPC). More specifically, this method for evaluating defects in a resist liquid is a method for measuring the size of defects in a liquid using a measuring instrument based on the light scattering intensity of a light scatterer. The measuring instrument is calibrated using the light scattering intensity of standard particles. Here, the standard particles used are, for example, polystyrene latex particles of different sizes.

[0011] FIG. 1 is a schematic diagram illustrating the behavior of light scattering from a light scatterer in a resist liquid in a comparative embodiment of a method for measuring defects in a resist liquid.

[0012] This method utilizes the phenomenon (intensity) of light scattering caused by irradiated laser light due to defects in the resist solution, such as metal particles A, bubbles (air bubbles) B, particles D that are different from bubbles B and metal particles A, and cluster defects E. When a sufficient signal-to-noise ratio (S / N ratio) can be obtained by comparing the signal intensity with the intensity of light scattering from the liquid itself without any light scatterers, this intensity is used to evaluate defects in the resist solution.

[0013] Specifically, the comparison form is a technology that measures "in-liquid defects of over 1000 nm, such as giant bubbles B exceeding 100 nm (0.1 μm), giant metal particles A, and cluster defects E," in comparison with "scattering intensity from resist liquid, including high molecular polymer resin C and cluster defects E."

[0014] The resist solution contains a high molecular weight polymer resin C in an organic solvent at a concentration of several percent. Therefore, background scattered light is measured along with the other components dissolved in the organic solvent, such as the photosensitizer and additives.

[0015] However, in addition to the above, there are other unintended defects in the resist solution, such as "metal particle A," "bubble B," and "particle D, which is different from bubble B and metal particle A," which become in-solution defects. Reducing these unintended defects is an important task in the resist manufacturing process.

[0016] The reason for this is as follows: The resist solution contains a mixture of high-molecular-weight polymer resin C, organic molecular components such as photosensitizers and additives, and metal particles A, bubbles B, and particles D that are different from metal particles A and are impurities in the resist. Clusters of "high-molecular-weight polymer resin C," "metal particles A," and "bubbles B and particles D that are different from metal particles A" form "cluster defects E." Cluster defects E, which are aggregates of organic components and impurities, are the cause of an increase in in-liquid defects when the resist solution is stored and left unattended, affecting resist quality. These cluster defects E are also a major cause of an increase in background scattered light.

[0017] Here, "metal particles A" are particles of silver, gold, iron oxide hydroxide, chromium oxide, etc. Furthermore, here, "particles D different from metal particles A" are, for example, particles of carbon, silica (quartz), or fluororesin.

[0018] In this embodiment, an organic solvent X that dissolves the cluster defects E is added to the resist solution to eliminate background scattered light from the cluster defects E. This allows the detection of true defects in the resist solution ("metal particles A," "bubbles B and particles D different from metal particles A").

[0019] It is preferable to detect the above-mentioned in-liquid defects by, for example, a measurement method using the principle of light scattering (Flow Particle Tracking: FPT) because it is possible to detect minute in-liquid defects. However, the above-mentioned in-liquid defect detection may also be performed by other methods. For example, the above-mentioned in-liquid defect detection may also be performed by a single particle ICP-MS method (spICP-MS method).

[0020] A part of a schematic diagram of a resist manufacturing method for explaining this embodiment is shown in Fig. 2. In other words, Fig. 2 is a schematic diagram of a resist manufacturing apparatus 500 of this embodiment.

[0021] A container 101 for storing a resist solvent, a container 107 for storing a high molecular weight polymer resin, a container 102 for storing a photosensitizer, and a container 103 for storing an additive are connected to a blending and mixing container (mixing container) 100. The resist solvent, the high molecular weight polymer resin, the photosensitizer, and the additive are then charged into the blending and mixing container 100. For example, the resist solvent is first charged, followed by the high molecular weight polymer resin C, then the photosensitizer, and finally the additive. The blending and mixing container 100 is, for example, a container made of SUS and having a fluororesin coating on the inside. However, the blending and mixing container 100 is not particularly limited to this.

[0022] The high molecular weight polymer resin C contains at least one compound selected from the group consisting of pyrazine-based, thiophene-based, fullerene-based, adamantane-based, heterocyclic-based, and fluorinated-based compounds, which are photosensitive materials used for, for example, g-line, i-line, KrF, ArF, etc.

[0023] Furthermore, the high molecular weight polymer resin C contains at least one compound selected from the group consisting of halogen compounds including bromine compounds, iodine compounds and fluorine compounds, and phenols, which are photosensitive materials used in, for example, EUV (Extreme ultraviolet lithography).

[0024] Next, the mixer 104 installed in the blending container 100 is used to stir and mix the resist raw materials, including the resist solvent, high molecular weight polymer resin C, photosensitizer, and additives. This results in a resist mixture of the resist solvent, high molecular weight polymer resin C, photosensitizer 102, and additives 103. Here, the mixer 104 is, for example, a stirring blade made of PTFE (polytetrafluoroethylene). However, the mixer 104 is not particularly limited to this.

[0025] Next, the resist mixture is sent from the bottom 100a of the blending and mixing container 100 to a filter 106 using a liquid suction and discharge pump 105. Here, the high molecular weight polymer resin C, photosensitizer 102, additive 103, etc. contained in the resist mixture are retained at the bottom of the blending and mixing container 100 due to gravity. Therefore, the resist mixture is extracted from the bottom 100a of the blending and mixing container 100.

[0026] The resist mixture is filtered by a filter 106 .

[0027] The filter 106 includes, for example, a filter 106a, a filter 106b, and a filter 106c. The filters 106a, 106b, and 106c are connected to each other in series, for example. In the embodiment, the number of filters used is three. However, the number of filters is not limited to three. For example, the filters 106a, 106b, and 106c each have a different type of membrane (film) used therein. The type, number, and connection order of the filters to be combined can be changed as appropriate depending on the type of in-liquid defects to be filtered and the number of in-liquid defects required in the resist mixture.

[0028] Here, for example, bottom 100a of blending / mixing container 100 and inlet 105a of liquid suction / discharge pump 105 are connected by pipe 108a. Furthermore, outlet 105b of liquid suction / discharge pump 105 and inlet 106a1 of filter 106a are connected by pipe 108b. Furthermore, outlet 106a2 of filter 106a and inlet 106b1 of filter 106b are connected by pipe 108c. Furthermore, outlet 106b2 of filter 106b and inlet 106c1 of filter 106c are connected by pipe 108d. The resist mixture discharged from outlet 106c2 of filter 106c is returned to blending / mixing container 100 by pipe 108e. In this way, the resist mixture is circulated and filtered by filter 106 multiple times.

[0029] The resist mixture from which defects have been sufficiently filtered by the filter 106 is filled into a container 111 using a filling unit 109 connected to the pipe 108e via a pipe 110. The container 111 is, for example, a container for shipping the resist mixture.

[0030] For example, the inlet 106a1 of the filter 106a is provided above the filter 106a. For example, the outlet 106a2 of the filter 106a is provided at the bottom of the filter 106a. The polymer resin C, the photosensitizer 102, the additive 103, and the like contained in the resist mixture move from the top to the bottom of the filter 106a due to gravity. Therefore, by arranging the inlet 106a1 and the outlet 106a2 of the filter 106a as described above, efficient filtration is achieved. The same applies to the filters 106b and 106c.

[0031] The resist mixture is then collected from a collection port α provided in the pipe 108b between the outlet 105b of the liquid suction and discharge pump 105 and the inlet 106a1 of the filter 106a (between the bottom 100a of the preparation mixing container 100 and the inlet 106a1 of the filter 106a).

[0032] The resist mixture is collected from a collection port β provided in a pipe 108e connected between the outlet 106c2 of the filter 106c and the preparation mixing container 100.

[0033] The control unit 120 performs, for example, the pouring of resist solvent from container 101 into the blending and mixing container 100, the pouring of high molecular weight polymer resin C from container 107 into the blending and mixing container 100, the pouring of photosensitizer from container 102 into the blending and mixing container 100, the pouring of additives from container 103 into the blending and mixing container 100, the stirring and mixing within the blending and mixing container 100 using the mixer 104, the on / off of the liquid suction and discharge pump 105, the control of the acquisition of the resist mixture from the acquisition ports α and β, the control of the first defect measurement unit 112a, the control of the filling unit 109, etc.

[0034] The control unit 120 is, for example, an electronic circuit, or a computer configured by a combination of hardware such as an arithmetic circuit and software such as a program.

[0035] Here, the first defect measurement unit 112a measures the type and number of in-liquid defects in the resist mixture acquired from the acquisition port α and the resist mixture acquired from the acquisition port β. Then, the in-liquid defects in the resist mixture acquired from the acquisition port α and the in-liquid defects in the resist mixture acquired from the acquisition port β are compared.

[0036] For example, if the difference obtained by subtracting the number of defects in the second liquid from the number of defects in the first liquid is equal to or less than a first predetermined value, the process of repeatedly transferring the resist mixture from the bottom 100a of the blending and mixing container 100 to the filter 106, filtering the resist mixture, and transferring the filtered resist mixture to the blending and mixing container can be stopped. This is because if the difference obtained by subtracting the number of defects in the second liquid from the number of defects in the first liquid is equal to or less than the first predetermined value, it is considered that the number of defects in the resist mixture has been sufficiently reduced. Note that this operation can be performed using, for example, the control unit 120.

[0037] After that, the filtered resist mixture can be filled into a container 111 using a filling unit 109 connected from the outlet of the filter 106 via a pipe 110 to a pipe 108e.

[0038] 3 is a schematic diagram illustrating a method for measuring defects in a resist liquid according to this embodiment, and is a schematic diagram illustrating the first defect measurement unit 112a in FIG.

[0039] In the first defect measurement unit 112a, a predetermined chemical liquid X is mixed with the resist mixture obtained from the acquisition port α and the acquisition port β. This dissolves cluster defects E in the resist mixture. Then, the in-liquid defects of the mixture mixed with the predetermined chemical liquid X are measured by the FPT method.

[0040] The flow rate of the resist mixture obtained from the intake port α is measured by a flow meter 301. The flow rate of the resist mixture obtained from the intake port β is measured by a flow meter 302.

[0041] A predetermined chemical liquid X is stored in a chemical liquid storage tank 306 of a chemical liquid purification and circulation unit 305. The predetermined chemical liquid X is filtered by a chemical liquid purification filter 308. The predetermined chemical liquid X is circulated by a chemical liquid circulation pump 307. In this way, the predetermined chemical liquid X is stored in the chemical liquid purification and circulation unit 305 while being filtered by the chemical liquid purification filter 308 in order to reduce in-liquid defects of the chemical liquid X as much as possible. Note that, for example, in-liquid defects of the predetermined chemical liquid X can be measured in advance using a first in-liquid defect measuring instrument 317.

[0042] The predetermined chemical solution X is not particularly limited, but may preferably be at least one solvent selected from the group consisting of aprotic polar solvents including tetrahydrofuran (THF), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), methyl ethyl ketone (MEK), and propylene glycol dimethyl ether (PGME), protic polar solvents, toluene, and ethyl acetate. For example, the predetermined chemical solution X may be the same organic solvent as the organic solvent contained in the resist mixture and stored in container 101.

[0043] A predetermined chemical liquid X passes through a valve 309a, and after its flow rate is measured by a flow meter 303, is mixed with the resist mixture obtained from the intake port α by a first mixer 311. This results in a first mixture. The first mixture passes through a valve 309c and is then sent to a first in-liquid defect measuring instrument 317. Here, defects in the first mixture are measured using a defect detection cell 314. The first mixture after the defects in the first liquid have been measured is collected by a drain 316.

[0044] If the flow rate of the first measured substance becomes too high, it may become difficult to detect defects in the liquid using the defect detection cell 314. Therefore, the flow rate of the first measured substance is controlled by a defect measurement cell flow rate regulator 315 provided between the defect detection cell 314 and the drain 316. If the flow rate of the first measured substance becomes too high, the first mixture may be sent from the valve 309c to the drain 316 via, for example, a bypass flow meter 313 without passing through the defect detection cell 314 and the defect measurement cell flow rate regulator 315.

[0045] Furthermore, the predetermined chemical liquid X passes through valve 309b, and after its flow rate is measured by flow meter 304, it is mixed with the resist mixture obtained from the intake port β by second mixer 312. This results in a second mixture. This second mixture passes through valve 309c and is then sent to first in-liquid defect measuring instrument 317. Here, second-liquid defects in the second mixture are measured using defect detection cell 314. The second mixture after the second-liquid defects have been measured is collected by drain 316.

[0046] If the flow rate of the second measurement object becomes too high, it may become difficult to detect defects in the liquid using the defect detection cell 314. Therefore, the flow rate of the second measurement object is controlled by a defect measurement cell flow rate regulator 315 provided between the defect detection cell 314 and the drain 316. If the flow rate of the second measurement object becomes too high, the second mixture may be sent from the valve 309c to the drain 316 via, for example, a bypass flow meter 313 without passing through the defect detection cell 314 and the defect measurement cell flow rate regulator 315.

[0047] The reason why the flow rate of the resist mixture obtained from the intake port α is measured by the flow meter 301 and the flow rate of the predetermined chemical liquid X is measured by the flow meter 303 is to precisely measure the amount of in-liquid defects in the first mixture by strictly controlling the amount of the predetermined chemical liquid X mixed into the first mixture.

[0048] The reason why the flow rate of the resist mixture obtained from the intake port β is measured by the flow meter 302 and the flow rate of the predetermined chemical liquid X is measured by the flow meter 304 is to precisely measure the amount of in-liquid defects in the second mixture by strictly controlling the amount of the predetermined chemical liquid X mixed into the second mixture.

[0049] Static mixers are preferably used as the first mixer 311 and the second mixer 312 used to mix the resist mixture and the predetermined chemical solution. A static mixer is a stationary mixer without a driving unit. For example, the first mixer 311 includes a pipe 311a and a plurality of right-handed helical elements 311b and left-handed helical elements 311c arranged alternately along the extension direction of the pipe 311a. The resist mixture obtained from the intake port α and the predetermined chemical solution X that has passed through the valve 309a are mixed by passing through the first mixer 311. Similarly, the second mixer 312 includes a pipe 312a and a plurality of right-handed helical elements 312b and left-handed helical elements 312c arranged alternately along the extension direction of the pipe 312a. The resist mixture obtained from the intake port β and the predetermined chemical solution X that has passed through the valve 309b are mixed by passing through the second mixer 312. The absence of a driving unit makes it possible to suppress an increase in defects in the liquid when mixing the resist mixture with the predetermined chemical liquid X. Note that other mixers may be used as the first mixer 311 and the second mixer 312.

[0050] It is preferable that the amount of the predetermined chemical solution X to be mixed and the structure of the static mixer are appropriately determined based on the time required for dissolving (re-decomposing) the cluster defects E, the appropriate amount of the predetermined chemical solution X to be added, the flow rate of the resist mixture, etc.

[0051] FIG. 4 is a schematic diagram of a defect detection cell (evaluation unit) 314 according to the embodiment.

[0052] The defect detection cell 314 acquires the particle diameter (geometric diameter) of the defect in the liquid by the FPT (Flow Particle Tracking) method.

[0053] FIG. 4(a) is a schematic diagram of a defect detection cell 314 according to the embodiment.

[0054] Here, an X-axis, a Y-axis that intersects the X-axis perpendicularly, and a Z-axis that intersects the X-axis and Y-axis perpendicularly are defined. The Z-axis is in the direction opposite to the vertical direction.

[0055] The column 52 is a transparent container capable of storing the first mixture or the second mixture. The flow of the first mixture or the second mixture in the column 52 is a laminar flow in the Z-axis direction. The column 52 is made of, for example, synthetic quartz or sapphire. A valve 309c, for example, is connected to a column inlet 52a of the column 52. Furthermore, a defect measurement cell flow regulator 315 is connected to a column outlet 52b of the column 52.

[0056] The irradiation unit (light source) 56 irradiates the first mixture or the second mixture in the column 52 with irradiation light such as laser light. For example, when the first mixture or the second mixture in the column 52 flows in the Z-axis direction, the irradiation unit 56 irradiates the first mixture or the second mixture with irradiation light in the X-axis direction. Note that the irradiation direction of the irradiation light is not limited to the X-axis direction.

[0057] The imaging unit 58 includes a charge coupled device (CCD) sensor or a complementary metal oxide semiconductor (CMOS) sensor (not shown). The imaging unit 58 captures an image of the first mixture or the second mixture in the column 52 using the lens 54 or the like. Then, a moving image of scattered light emitted from the defect in the liquid is acquired. FIG. 3(b) is an example of a schematic diagram of a moving image of metal particle A acquired by the imaging unit 58. The analysis unit 60 calculates the diffusion coefficient D of bubbles B, metal particle A, and particle D different from bubbles B and metal particles from the moving image. Here, metal particle A is an example of a first particle. Furthermore, particle D is an example of a second particle.

[0058] When a submerged defect undergoes Brownian motion in the first or second mixture, the diffusion coefficient D of the submerged defect can be calculated from a video image of the scattered light from the submerged defect. The diffusion coefficient D and the particle diameter d of the submerged defect are related by the following equation:

number

[0059] In equation (1), D is the diffusion coefficient of the submerged defect, kB is the Boltzmann constant, T is the absolute temperature, η is the viscosity (viscosity coefficient) of the first mixture or the second mixture, and d is the particle diameter of the submerged defect. The calculation unit 62 can calculate the particle diameter d of the submerged defect from the diffusion coefficient D using equation (1).

[0060] The refractive index of the liquid defect can be calculated using the following formula:

number

[0061] In equation (2), I is the intensity of scattered light, I0 is the intensity of incident light, c is the number concentration of the in-liquid defect, r is the distance from the in-liquid defect to the imaging unit 58, λ is the wavelength of the incident light, d is the particle diameter of the in-liquid defect, and m is the relative refractive index of the in-liquid defect with respect to the first mixture or the second mixture. The relative refractive index m is the refractive index n of the defect divided by the refractive index n0 of the first mixture or the second mixture (m = n / n0). If the refractive index n0 of the first mixture or the second mixture is known, the calculation unit 62 can calculate the refractive index n of the in-liquid defect using equation (2).

[0062] The determination unit 64 uses the refractive index n calculated by the calculation unit 62 to determine whether the in-liquid defect is a bubble or metal particle A, or a particle D. For example, the determination unit 64 is connected to a database 66 that stores the refractive indexes of known substances. For example, the determination unit 64 refers to the refractive indexes of these known substances in the above determination.

[0063] 5 shows an example of evaluation of a liquid containing a liquid-borne defect, performed using the defect detection cell (evaluation unit) 314 of the embodiment. In the graph shown in FIG. 5, the horizontal axis represents the particle diameter d of the liquid-borne defect, and the vertical axis represents the refractive index n of the liquid-borne defect calculated by the calculation unit 62.

[0064] 5 shows similar distributions above and below the refractive index n0 of the first mixture or the second mixture. In other words, the calculation unit 62 obtains two refractive indices n for the same particle diameter d, with the refractive index n0 of the first mixture or the second mixture as the center. This is because equation (2) is a quadratic equation of the relative refractive index m. Therefore, by comparing the relative refractive index m obtained by equation (2) with known refractive index data, the evaluation method of the embodiment becomes a semi-qualitative technique.

[0065] Specifically, when the refractive index of the first or second mixture to be measured is n0, the judgment unit 64 preferably judges the in-liquid defect to be a metal particle if the refractive index n is greater than n0 + (n0 - 1) or less than 1. Furthermore, when the refractive index of the first or second mixture to be measured is n0, the judgment unit 64 preferably judges the in-liquid defect to be a bubble or particle D if the refractive index n is greater than 1 or less than n0 + (n0 - 1). In other words, when the refractive index of the first or second mixture is set to n0 as the center and the refractive index n is calculated to be within the range of the difference between the refractive index n0 of the first or second mixture and the refractive index 1 of the bubble, the in-liquid defect is judged to be a particle D or a bubble. When the refractive index of the first or second mixture is set to n0 as the center and the refractive index n is calculated to be outside the range of the difference between the refractive index n0 of the first or second mixture and the refractive index 1 of the bubble, the in-liquid defect is judged to be a metal particle A. The refractive index n0 of the first mixture or second mixture to be measured is, for example, 1.2 to 1.5, but is not limited to this.

[0066] It is not necessary to provide the database 66. The determination unit 64 may simply use the magnitude relationship of the refractive indexes to distinguish between bubbles and metal particles.

[0067] 6 and 7 show more specific examples of evaluation of a liquid containing liquid-borne defects.

[0068] When the total number of defects detected in the refractive index range n>n0+(n0-1) is a(1) and the total number of defects detected in the refractive index range n<1 is a(2), the number of metal particles A in the liquid can be expressed by the following formula: (a(1)+a(2)) / 2 = number of metal particles A (3)

[0069] Furthermore, when the sum of the measured values ​​in the range of refractive index n where n0+(n0-1)≧n≧1 is a(3), the number of bubbles B or particles D in the liquid can be expressed by the following formula: a(3) / 2 = number of bubbles B or particles D (4)

[0070] In addition, by applying a(1), a(2), and a(3) for a certain defect diameter d to the above equation, it is possible to determine the number of metal particles A, bubbles B, or particles D for the defect diameter d.

[0071] In both equations, the sum of the measured values ​​for each defect type is divided by 2 because the refractive index n obtained from equation (2) has two solutions for each detected defect.

[0072] The distribution of defects detected from the defect diameter d and refractive index n calculated by the calculation unit 62 is shown in Figures 6 and 7. Figure 6 shows the distribution of defects in TMAH after passing through a 50 nm pore diameter filter. Figure 7 shows the distribution of defects in TMAH after passing through a 50 nm pore diameter filter and then a 10 nm pore diameter filter. The horizontal axis is the defect diameter d, and the vertical axis is the refractive index n.

[0073] 6 and 7, the defect diameter d (horizontal axis) is divided into 2.5 nm intervals in the range of 0 to 100 nm, and the refractive index n (vertical axis) is divided into 0.05 intervals in the range of 0 to 2.6, and the number of defects detected in each interval is shown. Areas in the distribution maps where one or more defects were detected are shown with the darkest color.

[0074] For example, consider determining the number of metal particles A, or bubbles B, and particles D from Figures 6 and 7. In this case, the refractive index of TMAH is 1.337, so the number of metal particles A is the sum of the number of defects detected in the refractive index range n>1.674 and n<1, divided by 2. Similarly, the number of bubbles B or particles D is the sum of the number of defects detected in the range 1.674≧n≧1, divided by 2.

[0075] As can be seen from FIG. 6, in the case of the 50 nm filter, one or more defects are detected in the region where the defect diameter d is 30-50 nm. In particular, the number of detected defects is high in the range where the refractive index is n > 1.674, n < 1. This indicates that many metal particles, bubbles, and other particles are slipping through. On the other hand, as can be seen from FIG. 7, in the case of the 10 nm filter, the number of detected defects is low in the range where the defect diameter d is 30-50 nm and the refractive index is n > 1.674, n < 1. This indicates that the number of metal particles is decreasing. Thus, it can be seen that the evaluation method of the embodiment can more appropriately evaluate the removal performance of a filter by using FPT measurement, which can determine the correct geometric diameter from the diffusion coefficient D.

[0076] The analysis unit 60, the calculation unit 62, and the determination unit 64 are, for example, electronic circuits. The analysis unit 60, the calculation unit 62, and the determination unit 64 are, for example, a computer configured by combining hardware such as an arithmetic circuit and software such as a program.

[0077] The database 66 is, for example, a storage device such as a semiconductor memory or a hard disk.

[0078] When detecting defects in liquid using the light scattering method, bubbles in the liquid are also detected as defects in the liquid, which makes it impossible to evaluate the filter collection performance for liquids that contain a large amount of bubbles.

[0079] In contrast, the FPT method makes it possible to determine whether the in-liquid defect is a bubble or particle D or a metal particle A by using the difference in refractive index.

[0080] Furthermore, when the refractive index of the first mixture or second mixture to be measured is n0, it is preferable to determine the in-liquid defect as a metal particle M when the refractive index n is greater than n0+(n0-1) or smaller than 1, and it is preferable to determine the in-liquid defect as a bubble or particle D when the refractive index n is 1 or greater or n0+(n0-1) or smaller.

[0081] The refractive index of particles containing metal is greater than 2.0 or less than 0.5. For example, the refractive index of silver is 0.17. The refractive index of gold is 0.34. The refractive index of iron oxide hydroxide is 2.00. The refractive index of chromium oxide (trivalent) is 2.50. Therefore, in-liquid defects with a refractive index greater than 2 or less than 0.5 may be determined to be metal particles M.

[0082] The refractive index of nitrogen (bubbles) is 1. The refractive index of ultrapure water is 1.33. The refractive index of fluororesin is 1.35. The refractive index of silica (quartz) is 1.45. The refractive index of polystyrene latex (PSL) is 1.59. Therefore, a liquid defect with a refractive index between 0.5 and 2 can be determined to be a bubble or particle D.

[0083] The pore diameter of the filter 80b is preferably 100 nm or less, because defects in the liquid having particle diameters larger than 100 nm do not undergo Brownian motion, making it difficult to determine the particle diameter d.

[0084] FIG. 8 shows a conceptual diagram of the light scattering background scattered light I that changes depending on the ratio of X added to two different polymeric resists, Sample A and Sample B.

[0085] In Sample A, the background scattered light intensity decreased and saturated at a volumetric concentration of approximately 50% when the X addition ratio, which dissolves cluster defects E formed by aggregation of organic components and impurities, was about 50%. Based on this result, the condition for measuring in-liquid defects in the resist of Sample A was set to mix X at a volume concentration of 50%.

[0086] In Sample B, the background scattered light intensity decreased and saturated at a volumetric concentration of approximately 30% when the volumetric concentration of X added was about 30%, which dissolves cluster defects E, which are aggregates of organic components and impurities. Based on this result, the condition for measuring in-liquid defects in the resist of Sample B was set to mix X at a volume concentration of 30%.

[0087] In this way, by adding an appropriate amount of a clean solvent capable of dissolving the cluster defects E, it is possible to reduce the background scattered light intensity caused by the cluster defects E, even in the case of a resist liquid. This makes it possible to correctly measure the presence of defects in the mixture other than the high molecular weight polymer resin during filtration, in the resist mixture obtained from the acquisition port α before passing through the filter 106, and in the resist mixture obtained from the acquisition port β after passing through the filter 106.

[0088] Next, an example of measuring defects during the resist manufacturing process and resist mixture filtration will be described.

[0089] (Example) Examples 1 to 3 will be explained below.

[0090] A resist mixture containing an organic solvent, a high molecular weight polymer resin, a photosensitizer, and additives as its main components is placed in a blending and mixing container 100. Next, a mixer 104 installed in the blending and mixing container 100 is used to agitate and mix the resist mixture. Next, a liquid suction and discharge pump 105 is operated. Regarding the "defects during filtration of the resist mixture" obtained at the acquisition port β, the change over time in the total amount of metal particles A measured by the FPT method during circulating filtration is shown in FIGS. 9, 10, and 11 as examples.

[0091] Example 1 As shown in FIG. 9, this example shows a case where the total amount of metal particles A in the resist mixture measured by the FPT method simply decreases over time.

[0092] The "metal particles A output in the RI (refractive index) measurement mode of the FPT" monotonically decreases with the filtration time (the time during which the resist mixture is circulated in the path including the filter 106 in the resist manufacturing equipment 500). Furthermore, defects with a geometric diameter of 12 nm or more in the DC measurement mode, which is the detection limit of the FPT method, are reduced to 100 particles / ml or less.

[0093] This defect number is the defect level in the organic solvent X liquid (predetermined chemical liquid X) used to dissolve the cluster defects E. Therefore, it is clear that in order to reduce this defect number, it is necessary to purify the organic solvent X liquid (predetermined chemical liquid X).

[0094] In this way, in the resist manufacturing process, when it is determined that the number of defects has been reduced to below the detection limit of the FPT method, the circulating filtration and purification of the resist mixture can be terminated, and the next process of resist shipping and resist bottle filling (container filling) can be started.

[0095] Furthermore, in the next process, when the resist is filled into the resist shipping bottle, the β liquid (resist mixture) obtained through the intake port β can be monitored at each of the initial, middle, and final stages of filling the resist bottle. This makes it possible to check for any changes in the metal particles A while the entire resist liquid in the resist mixing container is being filled into the bottle (for example, about 12 hours). This allows for simultaneous resist quality assurance.

[0096] Let's consider a case where the total amount of metal particles A in the resist mixture measured by the FPT method does not decrease monotonically with the elapsed time of filtration, but rather the behavior becomes unstable. In this case, after checking the progress over a certain period of time and confirming that the situation does not change, the resist mixture α liquid from the sampling port α (defect measurement sampling point α) before passing through the filter 106 (primary side) is also measured using the FPT to determine the number of defects. The number of defects in the liquid obtained by FPT measurement of the resist mixture β liquid obtained from the sampling port β after passing through the filter 106 (secondary side) is compared with the number of defects in the liquid obtained by FPT measurement of the liquid before passing through the filter 106 (primary side). If the numbers are found to be the same, it can be determined that the filter 106 is not performing its particle removal performance. For example, it can be determined that a breakthrough problem has occurred in the filter 106. Therefore, it is possible to immediately stop the circulation filtration and replace the filter.

[0097] Example 2 As shown in Figure 10, this example shows a case where the total amount of metal particles A in the resist mixture measured by the FPT method monotonically decreases until halfway through the filtration elapsed time, but the defect reduction reaches a saturation point along the way.

[0098] In the example shown in Figure 10, the total amount of metal particles A in the resist mixture measured by the FPT method monotonically decreased with the filtration time until halfway through, but did not decrease to the detection limit of the FPT method shown in Figure 9 (DC (diffusion equivalent diameter) measurement mode, defects with a geometric diameter of 12 nmφ or more, 100 particles / ml or less), and saturated at 10,000 particles / ml. In other words, the saturation level of the FPT method measurement results in the example shown in Figure 10 was higher than the saturation level of the FPT method measurement results in the example shown in Figure 9.

[0099] FIG. 11 shows the change over time in the number of defects, including bubbles B and other defects D, output in the RI (refractive index) measurement mode of the FPT.

[0100] For example, as shown in Figure 10, if the total amount of metal particles A in the resist mixture measured by the FPT method does not decrease, but decreases from the state where it should decrease (100 particles / ml or less) to a high state (the decrease has saturated), check the change in the number of defects (bubbles B + other defects D output in the FPT RI (refractive index) measurement mode) over time as shown in Figure 11. If the measurement results by the FPT method and the results output in the FPT RI (refractive index) measurement mode show similar behavior, it can be confirmed that the tailgating phenomenon of metal particles A due to the presence of bubbles B is occurring.

[0101] Generally, it is difficult to suppress the tailgating phenomenon of metal particles A caused by bubbles B using a filter. Therefore, it can be concluded that further circulating filtration and purification is meaningless in terms of reducing defects. Therefore, the liquid suction and discharge pump 105 is stopped.

[0102] Furthermore, if a filter that has the effect of suppressing the entrainment of metal particles A by bubbles B can be obtained, it is thought that the number of defects can be reduced by circulating filtration and purification even in resists that tend to foam and have bubbles in the liquid.

[0103] In this way, by applying the embodiment to the resist manufacturing process, it is possible to correctly evaluate the defect amount in the resist mixed solution after circulating, filtering, and purifying, which allows for accurate quality checks in the resist circulating and purifying process, and allows for the next process, which is filling the resist bottles.

[0104] Example 4 FIG. 12 shows the dependency of the mixing ratio of the resist mixture and the predetermined chemical solution X measured by the FPT method.

[0105] When the specified chemical solution X is not mixed, the intensity of the noise signal caused by cluster defects E is very high, as shown in Figure 12(a). Therefore, only relatively large in-liquid defects with a defect particle diameter of about 100 nm can be detected.

[0106] Fig. 12(b) shows the measurement results of in-liquid defects by the FPT method when the mixing ratio of the resist mixture to the predetermined chemical liquid X is 7:3, and Fig. 12(c) shows the measurement results of in-liquid defects by the FPT method when the mixing ratio of the resist mixture to the predetermined chemical liquid X is 5:5.

[0107] 12(b) and 12(c), when the mixing ratio of the predetermined chemical liquid X is increased, the number of signals detected from in-liquid defects with a defect particle diameter of approximately 100 nm decreases. This is because the number of in-liquid defects in the solution decreases as the mixing ratio of the predetermined chemical liquid X increases.

[0108] On the other hand, in FIG. 12(b), signals from in-liquid defects with a defect particle diameter of approximately 70 nm can be measured. Also, in FIG. 12(c), signals from in-liquid defects with a defect particle diameter of approximately 50 nm can be measured. This is because, as the specified chemical solution X is mixed, cluster defects E dissolve, reducing the intensity of the noise signal caused by cluster defects E. In other words, by using the FPT method to measure the resist mixture mixed with the specified chemical solution X rather than measuring the resist mixture itself, the signal measurable range can be increased depending on the mixture ratio. As a result, the resist manufacturing method of this embodiment can appropriately control defects in the resist solution during circulating filtration and purification.

[0109] FIG. 12(d) shows the measurement results of in-liquid defects measured for a predetermined chemical liquid X using the FPT method.

[0110] (Second embodiment) The resist manufacturing method of this embodiment differs from the resist manufacturing method of the first embodiment in that it further includes a step of measuring defects in the first liquid of the first mixture irradiated with the irradiation light using an SP-ICP-MS method.

[0111] The resist manufacturing method of this embodiment also differs from the resist manufacturing method of the first embodiment in that defects in the first liquid of the first mixture are measured using an SP-ICP-MS method.

[0112] Here, the description of the contents that overlap with the first embodiment will be omitted.

[0113] 13 is a schematic diagram illustrating a method for measuring defects in a resist liquid according to this embodiment, and is a schematic diagram illustrating a first defect measurement unit 112b according to this embodiment.

[0114] After the first liquid defects of the first mixture are measured using defect detection cell 314 of first liquid defect measurement instrument 317, the first mixture is sent to second liquid defect measurement instrument 318 before being collected in drain 316. Then, the first liquid defects of the first mixture are measured using second liquid defect measurement instrument 318. Second liquid defect measurement instrument 318 measures the first liquid defects of the first mixture by SP-ICP-MS (Single-Particle ICP (Inductively Coupled Plasma)-MS (Mass Spectrometry)) method. By using the SP-ICP-MS method, it is possible to obtain elemental information of metal particle A detected by first liquid defect measurement instrument 317.

[0115] 14 shows an example of a liquid evaluation including submerged defects, performed using the defect detection cell 314 of this embodiment. As the liquid passes through the filter 106, the total number of defects, the number of metal particles A, and the number of bubbles B or particles D decrease. Then, for example, when the total number of defects, the number of metal particles A, the number of bubbles B, or particles D becomes equal to or less than a predetermined threshold, it is deemed possible to fill the container 111.

[0116] FIG. 15 shows an example of a liquid evaluation including submerged defects, performed using the second submerged defect measuring instrument 318 of this embodiment. When performing measurement using the SP-ICP-MS method, information on the time change in intensity of a specific type of atomic species (e.g., Fe, etc.) can be obtained. For example, when measuring the submerged defects of the first mixture before passing through the filter 106, high-intensity signals obtained by the SP-ICP-MS method are frequently observed. By passing through the filter 106, the intensity of the signals obtained by the SP-ICP-MS method decreases. Furthermore, by passing through the filter 106, the frequency of the signals obtained by the SP-ICP-MS method decreases. Then, for example, taking into consideration the frequency and intensity of the signals obtained by the SP-ICP-MS method, it is determined whether or not the container 111 can be filled.

[0117] 16 is a schematic diagram illustrating a method for measuring in-liquid defects in a resist liquid in another aspect of this embodiment. In the first defect diameter side portion 112c in FIG. 16, the first in-liquid defects of the first mixture are measured using a second in-liquid defect measuring instrument 318. The defect detection cell 314 of the first in-liquid defect measuring instrument 317 is not used.

[0118] By applying this embodiment to the resist manufacturing process, it becomes possible to correctly evaluate the defect amount in the resist mixture after circulating, filtering, and refining, thereby enabling accurate quality confirmation in the resist circulating and refining process.

[0119] (Third embodiment) The resist manufacturing method of this embodiment differs from the resist manufacturing methods of the first and second embodiments in that it further includes the steps of: obtaining a third mixture by mixing the filtered resist mixture with a predetermined second chemical liquid; measuring defects in the third liquid of the third mixture; obtaining a fourth mixture by mixing the resist mixture filled in a container with a predetermined second chemical liquid; measuring defects in the fourth liquid of the fourth mixture; and comparing the defects in the third liquid with the defects in the fourth liquid.

[0120] Furthermore, the resist manufacturing method of this embodiment differs from the resist manufacturing methods of the first and second embodiments in that the step of comparing the defects in the third liquid with the defects in the fourth liquid includes a step of sending the resist mixture filled in the container to a mixing container if the difference obtained by subtracting the number of defects in the third liquid from the number of defects in the fourth liquid is greater than a second predetermined value.

[0121] Here, descriptions that overlap with the resist manufacturing methods of the first and second embodiments will be omitted.

[0122] 17 and 18 are schematic diagrams illustrating a resist manufacturing method according to this embodiment.

[0123] In the resist manufacturing method, it is very important to fill the resist mixture into a container such as a resist bottle while keeping the amount of defects in the resist mixture low. Figures 17 and 18 are schematic diagrams showing the filling unit 109 (Figure 2) and the container 111 (Figure 2) into which the resist is filled.

[0124] The filtered resist mixture is filled into containers 111a, 111b, 111c, and 111d, which are resist bottles, using a pipe 109a connected to a pipe 108e. Note that although the number of containers is four here, the number of containers is not limited to four.

[0125] Here, the resist mixture before being filled into the containers 111a, 111b, 111c, and 111d is introduced into the second defect measurement unit 112d from the acquisition port α2 using the pipe 109b (FIGS. 17 and 18). The resist mixture after being filled into the containers 111a, 111b, 111c, and 111d is introduced into the second defect measurement unit 112d from the acquisition port β2 using the pipe 109d (FIG. 18). Then, the type and number of in-liquid defects are measured for the resist mixture obtained from the acquisition port α2 and the resist mixture obtained from the acquisition port β2 using the second defect measurement unit 112d. Then, the third in-liquid defects of the resist mixture obtained from the acquisition port α2 and the fourth in-liquid defects of the resist mixture obtained from the acquisition port β2 are compared.

[0126] The second defect measurement unit 112d has the same configuration as the first defect measurement unit 112a, 112b, or 112c. In the second defect measurement unit 112d, a predetermined chemical liquid Y is mixed with the resist mixture acquired from the acquisition port α2 and the acquisition port β2. Then, in-liquid defects in the mixture into which the predetermined chemical liquid Y has been mixed are measured by the FPT method.

[0127] The predetermined chemical solution Y is not particularly limited, but may preferably be at least one solvent selected from the group consisting of aprotic polar solvents including tetrahydrofuran (THF), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), methyl ethyl ketone (MEK), and propylene glycol dimethyl ether (PGME), protic polar solvents, toluene, and ethyl acetate. For example, the predetermined chemical solution Y may be the same organic solvent as the organic solvent contained in the resist mixture and stored in container 101.

[0128] The predetermined chemical liquid Y may be a chemical liquid different from the predetermined chemical liquid X, or may be the same chemical liquid as the predetermined chemical liquid X. Here, the predetermined chemical liquid X is an example of a "predetermined first chemical liquid," and the predetermined chemical liquid Y is an example of a "predetermined second chemical liquid."

[0129] For example, if the difference obtained by subtracting the number of defects in the third liquid from the number of defects in the fourth liquid is greater than a second predetermined value, the resist mixture filled in the containers 111a, 111b, 111c, and 111d can be returned to the blending and mixing container 100 via the pipe 109c. Here, "the difference obtained by subtracting the number of defects in the third liquid from the number of defects in the fourth liquid is greater than a second predetermined value" means that the number of defects in the resist mixture has increased as a result of filling the containers. According to the resist manufacturing method of this embodiment, even if the number of defects in the resist mixture has increased as a result of filling the container 111, the resist mixture can be returned to the blending and mixing container 100, the number of defects can be reduced, and the container can be filled again. This operation can be performed, for example, using the control unit 120 (FIG. 2).

[0130] In other words, according to the resist manufacturing method of this embodiment, the containers 111a, 111b, 111c, and 111d, which are resist bottles, can be cleaned using the resist mixture to be filled in. The resist mixture, which has had an increased number of in-liquid defects due to cleaning, is returned to the blending container 100, where the number of in-liquid defects is reduced before being filled into the containers.

[0131] Although several embodiments and examples of the present invention have been described, these embodiments and examples are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims.

[0132] The above-described embodiments can be summarized as the following technical proposals. (Technical proposal 1) Mixing resist raw materials in a mixing container to obtain a resist mixture; directing the resist mixture from the bottom of the mixing vessel to the inlet of a filter having an inlet and an outlet; filtering the resist mixture using the filter; delivering the filtered resist mixture through the outlet to the mixing vessel; A process of repeating the above steps; obtaining a first mixture by mixing the resist mixture obtained between the bottom of the mixing container and the inlet with a predetermined first chemical liquid; measuring defects in a first liquid of the first mixture; obtaining a second mixture by mixing the resist mixture obtained between the outlet and the mixing container with the predetermined first chemical liquid; measuring defects in a second liquid of the second mixture; comparing the first liquid-submerged defect with the second liquid-submerged defect; A resist manufacturing method comprising: (Technical proposal 2) The step of comparing the first liquid-submerged defect with the second liquid-submerged defect includes: When the difference obtained by subtracting the number of defects in the second liquid from the number of defects in the first liquid is equal to or less than a first predetermined value, directing the resist mixture from the bottom of the mixing vessel to the inlet of the filter, the filter having the inlet and the outlet; filtering the resist mixture using the filter; delivering the filtered resist mixture through the outlet to the mixing vessel; and stopping the step of repeating the steps. A resist manufacturing method according to Technical Proposal 1. (Technical proposal 3) directing the resist mixture from the bottom of the mixing vessel to the inlet of the filter, the filter having the inlet and the outlet; filtering the resist mixture using the filter; delivering the filtered resist mixture through the outlet to the mixing vessel; and after the step of stopping the step of repeating the steps of (a) and (b), a step of filling the filtered resist mixture into a container through the outlet. A resist manufacturing method according to Technical Proposal 2. (Technical proposal 4) mixing the filtered resist mixture with a predetermined second chemical liquid to obtain a third mixture; measuring defects in a third liquid of the third mixture; obtaining a fourth mixture by mixing the resist mixture filled in the container with the predetermined second chemical liquid; measuring defects in the fourth liquid of the fourth mixture; comparing the third liquid-submerged defect with the fourth liquid-submerged defect; The resist manufacturing method according to Technical Solution 3 further comprises: (Technical proposal 5) The step of comparing the third liquid-in-defect and the fourth liquid-in-defect includes: sending the resist mixture filled in the container to the mixing container when a difference obtained by subtracting the number of defects in the third liquid from the number of defects in the fourth liquid is greater than a second predetermined value; The resist manufacturing method according to Technical Solution 4, comprising: (Technical proposal 6) The step of measuring the defects in the third liquid includes: Sending the third mixture containing the predetermined second chemical solution to a transparent second column; subjecting the third mixture in the second column to a second irradiation with a second irradiation light; capturing an image of second scattered light emitted from the third submerged defect by the second irradiation; determining a second diffusion coefficient of the third submerged defect from the captured second scattered light; calculating a second particle diameter of the third in-liquid defect and a second refractive index of the third in-liquid defect using the second diffusion coefficient; Using the second refractive index, the third liquid defect is The first particle contains a metal, a foam or second particles different from the foam and the first particles; a step of determining whether having A resist manufacturing method according to Technical Proposal 4. (Technical proposal 7) The predetermined first chemical liquid and the predetermined second chemical liquid are the same chemical liquid. A resist manufacturing method according to Technical Proposal 4. (Technical proposal 8) The step of measuring defects in the first liquid includes: Sending the first mixture containing the predetermined first chemical solution to a transparent first column; applying a first irradiation of a first irradiation light to the first mixture in the first column; capturing an image of first scattered light emitted from the first submerged defect by the first irradiation; determining a first diffusion coefficient of the first submerged defect from the captured first scattered light; calculating a first particle size of the first submerged defect and a first refractive index of the first submerged defect using the first diffusion coefficient; Using the first refractive index, the first liquid-submerged defect is The first particle contains a metal, a foam or second particles different from the foam and the first particles; a step of determining whether having A resist manufacturing method according to Technical Proposal 1. (Technical proposal 9) The step of measuring defects in the first liquid includes: measuring defects in the first liquid of the first mixture irradiated with the first irradiation light by using an SP-ICP-MS method; further comprising A resist manufacturing method according to Technical Proposal 8. (Technical proposal 10) measuring defects in the first liquid of the first mixture using an SP-ICP-MS method; A resist manufacturing method according to Technical Proposal 8. (Technical proposal 11) The raw material contains at least one compound selected from the group consisting of pyrazine-based compounds, thiophene-based compounds, fullerene-based compounds, adamantane-based compounds, heterocyclic compounds, and fluorinated compounds. A resist manufacturing method according to Technical Proposal 1. (Technical proposal 12) The raw material contains at least one compound selected from the group consisting of halogen compounds including bromine compounds, iodine compounds, and fluorine compounds, and phenols. A resist manufacturing method according to Technical Proposal 1. (Technical proposal 13) The predetermined first chemical solution contains at least one solvent selected from the group consisting of aprotic polar solvents, including tetrahydrofuran (THF), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), methyl ethyl ketone (MEK), and propylene glycol dimethyl ether (PGME), protic polar solvents, toluene, and ethyl acetate; A resist manufacturing method according to Technical Proposal 1. (Technical proposal 14) The resist mixture and a predetermined first chemical solution are mixed using a static mixer. A resist manufacturing method according to Technical Proposal 1. [Explanation of symbols]

[0133] 52: Column 52a: Column inlet 52b: Column outlet 54: Lens 56: Irradiation unit 58: Imaging unit 59: Surface technology 60:Analysis Department 62: Calculation section 64: Judgment Department 66: Database 80b: Filter 100: Mixing container 100b: Bottom 101: Container for storing resist solvent 102: Container for storing additives 103: Container for storing photosensitive agent 104: Mixer 105: Liquid suction and discharge pump 105a: Entrance 105b:Exit 106: Filter 106a: Filter 106a1:Entrance 106a2:Exit 106b: Filter 106b1:Entrance 106b2:Exit 106c: Filter 106c1:Entrance 106c2:Exit 107: Container 108a: Piping 108b:Plumbing 108c:Plumbing 108d: Piping 108e:Plumbing 109: Filling section 109a:Plumbing 109b:Plumbing 109c:Plumbing 109d: Piping 110: Piping 111: Container 112a: First defect measurement unit 112b: First defect measurement unit 112c: First defect diameter side 112d: Second defect measurement section 120: Control unit 301:Flow meter 302:Flow meter 303:Flow meter 304:Flowmeter 305: Chemical purification and circulation unit 306: Chemical storage tank 307: Chemical circulation pump 308: Chemical purification filter 309a: Valve 309b: Valve 309c: Valve 311: First mixer (static mixer) 312: Second mixer (static mixer) 313: Bypass flow meter 314: Defect detection cell 315: Defective measuring cell flow regulator 316: Drain (recovery) 317: First liquid-submerged defect measuring instrument 318: Second liquid-submerged defect measuring instrument 500: Resist manufacturing equipment A: Metal particles B: Bubbles (air bubbles) C: High molecular weight polymer resin D: Foam B and metal particles different from A E: Cluster defects α: Acquisition port (defect measurement point / liquid before passing through filter 106) β: Acquisition port (defect measurement point / liquid after passing through filter 106) α2: Acquisition port (defect measurement point / liquid before filling container 111) β2: Acquisition port (defect measurement point after filling container 111 / liquid)

Claims

1. Mixing resist raw materials in a mixing container to obtain a resist mixture; directing the resist mixture from the bottom of the mixing vessel to the inlet of a filter having an inlet and an outlet; filtering the resist mixture using the filter; delivering the filtered resist mixture through the outlet to the mixing vessel; A process of repeating the above steps; obtaining a first mixture by mixing the resist mixture obtained between the bottom of the mixing container and the inlet with a predetermined first chemical liquid; measuring defects in a first liquid of the first mixture; obtaining a second mixture by mixing the resist mixture obtained between the outlet and the mixing container with the predetermined first chemical liquid; measuring defects in a second liquid of the second mixture; comparing the first liquid-submerged defect with the second liquid-submerged defect; A resist manufacturing method comprising:

2. The step of comparing the first liquid-submerged defect with the second liquid-submerged defect includes: When the difference obtained by subtracting the number of defects in the second liquid from the number of defects in the first liquid is equal to or less than a first predetermined value, directing the resist mixture from the bottom of the mixing vessel to the inlet of the filter, the filter having the inlet and the outlet; filtering the resist mixture using the filter; delivering the filtered resist mixture through the outlet to the mixing vessel; and stopping the step of repeating the steps. The resist manufacturing method according to claim 1.

3. directing the resist mixture from the bottom of the mixing vessel to the inlet of the filter, the filter having the inlet and the outlet; filtering the resist mixture using the filter; delivering the filtered resist mixture through the outlet to the mixing vessel; and after the step of stopping the step of repeating the steps of (a) and (b), a step of filling the filtered resist mixture into a container through the outlet.

3. The resist manufacturing method according to claim 2.

4. mixing the filtered resist mixture with a predetermined second chemical liquid to obtain a third mixture; measuring defects in a third liquid of the third mixture; obtaining a fourth mixture by mixing the resist mixture filled in the container with the predetermined second chemical liquid; measuring defects in a fourth liquid of the fourth mixture; comparing the third liquid-submerged defect with the fourth liquid-submerged defect; The resist manufacturing method according to claim 3, further comprising:

5. The step of comparing the third liquid-in-liquid defect with the fourth liquid-in-liquid defect includes: sending the resist mixture filled in the container to the mixing container when a difference obtained by subtracting the number of defects in the third liquid from the number of defects in the fourth liquid is greater than a second predetermined value; The resist manufacturing method according to claim 4, comprising the steps of:

6. The step of measuring the third in-liquid defect includes: Sending the third mixture containing the predetermined second chemical solution to a transparent second column; subjecting the third mixture in the second column to a second irradiation with a second irradiation light; capturing an image of second scattered light emitted from the third submerged defect by the second irradiation; determining a second diffusion coefficient of the third in-liquid defect from the captured second scattered light; calculating a second particle diameter of the third in-liquid defect and a second refractive index of the third in-liquid defect using the second diffusion coefficient; Using the second refractive index, the third liquid defect is a first particle containing a metal; a foam or second particles different from the foam and the first particles; a step of determining whether having 5. The resist manufacturing method according to claim 4.

7. The predetermined first chemical liquid and the predetermined second chemical liquid are the same chemical liquid.

5. The resist manufacturing method according to claim 4.

8. The step of measuring the defect in the first liquid includes: sending the first mixture containing the predetermined first chemical solution to a transparent first column; subjecting the first mixture in the first column to a first irradiation of a first irradiation light; capturing an image of first scattered light emitted from the first submerged defect by the first irradiation; determining a first diffusion coefficient of the first submerged defect from the captured first scattered light; calculating a first particle size of the first liquid-submerged defect and a first refractive index of the first liquid-submerged defect using the first diffusion coefficient; Using the first refractive index, the first liquid-submerged defect is a first particle containing a metal; a foam or second particles different from the foam and the first particles; a step of determining whether having The resist manufacturing method according to claim 1.

9. The step of measuring the defect in the first liquid includes: measuring defects in the first liquid of the first mixture irradiated with the first irradiation light by using an SP-ICP-MS method; further comprising 9. The resist manufacturing method according to claim 8.

10. measuring defects in the first liquid of the first mixture using an SP-ICP-MS method; 9. The resist manufacturing method according to claim 8.

11. the raw material contains at least one compound selected from the group consisting of pyrazine-based compounds, thiophene-based compounds, fullerene-based compounds, adamantane-based compounds, heterocyclic compounds, and fluorinated compounds; The resist manufacturing method according to claim 1.

12. The raw material contains at least one compound selected from the group consisting of halogen compounds including bromine compounds, iodine compounds, and fluorine compounds, and phenols. The resist manufacturing method according to claim 1.

13. The predetermined first chemical solution contains at least one solvent selected from the group consisting of aprotic polar solvents including tetrahydrofuran (THF), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), methyl ethyl ketone (MEK), and propylene glycol dimethyl ether (PGME), protic polar solvents, toluene, and ethyl acetate; The resist manufacturing method according to claim 1.

14. The resist mixture and a predetermined first chemical solution are mixed using a static mixer. The resist manufacturing method according to claim 1.

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