Containerized etching solution composition

Abstract

To provide a packed-in-container etchant composition, of which the number of particles in liquid is reduced according to an embodiment.SOLUTION: The disclosure hereof relates to a packed-in-container etchant composition in one embodiment. The packed-in-container etchant composition is an etchant composition for etching an etching-target layer containing at least one kind of metal, which is set in a container. In the packed-in-container etchant composition, the number of in-liquid particles of 200 nm or larger in particle size is 0 / mL or more and 100 / mL or less; the number of in-liquid particles of 300 nm or larger in particle size is 0 / mL or more and 50 / mL or less; and the number of in-liquid particles of 500 nm or larger in particle size is 0 / mL or more and 20 / mL or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a containerized etching solution composition, a method for filling the etching solution composition, and a method for producing the containerized etching solution composition. [Background technology]

[0002] In the manufacturing process of a semiconductor device, a step is carried out in which a layer to be etched, which contains at least one metal such as tungsten, tantalum, zirconium, hafnium, molybdenum, niobium, ruthenium, osmium, rhenium, rhodium, copper, nickel, cobalt, titanium, titanium nitride, alumina, aluminum, and iridium, is etched into a predetermined pattern shape. Typically, an etching solution composition is filled into a container and then commercialized. When the etching solution composition is filled into the container, a filtration process using a filter or the like is carried out to reduce the content of foreign matter (particles) in the etching solution composition.

[0003] As a method for reducing the content of foreign matter in a liquid composition, for example, Patent Document 1 proposes a method in which, when filling multiple containers, the opening of the filling valve is adjusted so that the total filling flow rate through multiple filling nozzles is constant, thereby suppressing pressure fluctuations across the filter caused by the opening and closing operation of the filling valve, thereby preventing foreign matter from passing through the filter. Patent document 2 proposes a method for improving the filtering accuracy of a filter by controlling the opening degree of the recovery valve (circulation valve) so that the pressure between the upstream and downstream sides of the filter, which is generated by the opening and closing operation of the filling valve, does not fluctuate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-114067 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-83882 Summary of the Invention [Problem to be solved by the invention]

[0005] The presence of foreign matter (particles) in an etching solution composition can lead to problems such as poor cleanliness of the substrate after etching and contamination of the inside of the etching treatment equipment. In particular, when a filter for removing foreign matter is installed in the chemical solution supply line of an etching treatment equipment, the filter can become clogged in a short period of time, resulting in a decrease in productivity. Therefore, an etching solution composition with a low particle count is desired. However, conventional filling systems are insufficient to sufficiently reduce the number of particles in the etching solution composition filled in a container.

[0006] Therefore, in one aspect, the present disclosure provides an etching solution composition in which the number of particles in the liquid is reduced when the etching solution composition is filled into a container, and a method for filling the same. [Means for solving the problem]

[0007] In one aspect, the present disclosure relates to a container-packed etching solution composition in which a container is filled with an etching solution composition for etching a layer to be etched that contains at least one metal, wherein the number of in-solution particles having a particle diameter of 200 nm or more in the container-packed etching solution composition is 0 particles / mL or more and 100 particles / mL or less, the number of in-solution particles having a particle diameter of 300 nm or more in the container-packed etching solution composition is 0 particles / mL or more and 50 particles / mL or less, and the number of in-solution particles having a particle diameter of 500 nm or more in the container-packed etching solution composition is 0 particles / mL or more and 20 particles / mL or less.

[0008] In one aspect, the present disclosure provides a method for manufacturing an etching solution comprising: a tank for storing an etching solution composition; a pump provided downstream of the tank for delivering the etching solution composition; a filter provided downstream of the pump for filtering the etching solution composition; an outlet valve provided downstream of the filter for controlling the flow rate of the etching solution composition discharged from an outlet; piping connecting the tank, the pump, the filter, the outlet valve, and an outlet; a circulation path branching from the piping between the filter and the outlet valve and connecting to the upstream side of the pump; and a circulation valve for controlling the flow rate of the etching solution composition circulating through the circulation path; The etching solution composition is filled into a container using a filling system that is configured to: pump a substance, filter it with a filter, open an outlet valve, discharge the etching solution composition from the outlet, fill a container with the etching solution composition; open a circulation valve while the outlet valve is open and while the outlet valve is closed, and circulate the etching solution composition through a circulation path; and adjust the flow rate of the etching solution composition circulating through the circulation path to be 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet.

[0009] In one aspect, the present disclosure provides a method for filling a container with an etching solution composition for etching a layer to be etched that contains at least one metal, the method comprising: a step of pumping the etching solution composition in the tank and filtering it using a filling system comprising: a tank for storing the etching solution composition; a pump provided downstream of the tank for pumping the etching solution composition; a filter provided downstream of the pump for filtering the etching solution composition; an outlet valve provided downstream of the filter for controlling the flow rate of the etching solution composition discharged from an outlet; piping connecting the tank, the pump, the filter, the outlet valve, and the outlet; a circulation path branching from the piping between the filter and the outlet valve and connecting to the upstream side of the pump; and a circulation valve for controlling the flow rate of the etching solution composition circulating through the circulation path; a step of opening an outlet valve and filling a container with the etching solution composition discharged from the outlet, The method further includes a step of opening the circulation valve while the outlet valve is open and while the outlet valve is closed, and circulating the etching solution composition through the circulation path; The flow rate of the etching solution composition circulating through the circulation path is adjusted to 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet.

[0010] In one aspect, the present disclosure relates to a method for producing a containerized etching solution composition, in which an etching solution composition filled in a container is produced using the filling method of the present disclosure. [Effects of the Invention]

[0011] According to one aspect of the present disclosure, an etching solution composition in which the number of particles in the liquid in the etching solution composition filled in a container is reduced, and a method for filling the same can be provided. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram illustrating one embodiment of a filling system. [Figure 2] FIG. 2 is a schematic diagram illustrating the filtration process by a filter when a conventional filling system is used. DETAILED DESCRIPTION OF THE INVENTION

[0013] As a result of extensive research, the present inventors have surprisingly found that the above-mentioned problems can be solved by circulating the etching solution composition from the downstream side of the filter to the upstream side of the pump under predetermined conditions not only while the outlet valve is closed (i.e., while filling into the container is stopped) but also while the outlet valve is open (i.e., while filling into the container).

[0014] That is, in one aspect, the present disclosure relates to a container-packed etching solution composition in which a container is filled with an etching solution composition for etching a layer to be etched that contains at least one metal, wherein the number of submerged particles having a particle diameter of 200 nm or more in the container-packed etching solution composition is 0 particles / mL or more and 100 particles / mL or less, the number of submerged particles having a particle diameter of 300 nm or more in the container-packed etching solution composition is 0 particles / mL or more and 50 particles / mL or less, and the number of submerged particles having a particle diameter of 500 nm or more in the container-packed etching solution composition is 0 particles / mL or more and 20 particles / mL or less. In one aspect, the present disclosure provides an etching solution composition storage system including: a tank for storing an etching solution composition; a pump that is provided downstream of the tank and delivers the etching solution composition; a filter that is provided downstream of the pump and filters the etching solution composition; an outlet valve that is provided downstream of the filter and controls the flow rate of the etching solution composition discharged from an outlet; piping that connects the tank, the pump, the filter, the outlet valve, and the outlet; a circulation path that branches off from the piping between the filter and the outlet valve and connects to the upstream side of the pump; and a circulation valve that controls the flow rate of the etching solution composition circulated through the circulation path; the etching solution composition for etching a layer to be etched that contains at least one metal is filled into a container using a filling system configured to: pump a composition, filter it with a filter, open an outlet valve, discharge the etching solution composition from an outlet, fill a container with the etching solution composition; open a circulation valve while the outlet valve is open and while it is closed to circulate the etching solution composition through a circulation path; and adjust the flow rate of the etching solution composition circulating through the circulation path to 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet. Hereinafter, these containerized etching solution compositions will also be collectively referred to as "containerized etching solution compositions of the present disclosure." According to the container-packed etching solution composition of the present disclosure, it is possible to provide a container-packed etching solution composition with a reduced number of particles in the solution.

[0015] Although the details of the mechanism by which the effects of the present disclosure are manifested are not clear, it is presumed as follows. In conventional filling methods, the etching solution composition is filtered using a filter before being filled into a container. As shown in FIG. 2(a), particles A in the etching solution composition are trapped by filter 3, and aggregates of particles A are formed on the upstream side (inlet side) of filter 3. The arrows in FIG. 2 indicate the direction of liquid flow. When replacing a container, the outlet valve is closed to stop filling the container. After the container replacement, the outlet valve is opened and filling into a new container is resumed. However, this opening and closing of the outlet valve changes the amount of liquid passing through the filter, causing the pressure on the downstream side (outlet side) of filter 3 to become greater than the pressure on the upstream side (inlet side). This creates back pressure, causing the etching solution composition to flow back from the downstream side (outlet side) of filter 3 to the upstream side (inlet side), as shown in FIG. 2(b). This is thought to cause the aggregates of particles A trapped by filter 3 to collapse. Then, as shown in FIG. 2(c), it is considered that particles A that had been captured by filter 3 before the container replacement pass through filter 3 (are not filtered), and the number of particles in the liquid of the etching solution composition filled in the new container 6 increases. Therefore, in one or more embodiments of the present disclosure, regardless of the opening and closing operation of the outlet valve, the filtered etching solution composition is circulated from the downstream side of the filter to the upstream side of the pump while the outlet valve is open or closed. This presumably prevents the pressure on the outlet side of the filter from becoming larger than that on the inlet side due to the opening and closing operation of the outlet valve, and thus prevents an increase in the number of particles in the etching solution composition filled into the container after filling is resumed. However, the present disclosure need not be construed as being limited to these mechanisms.

[0016] [Containerized Etching Solution Composition] In one or more embodiments, the containerized etching solution composition of the present disclosure is an etching solution composition for etching a layer to be etched that contains at least one metal, filled in a container. In one or more embodiments, the containerized etching solution composition of the present disclosure is an etching solution composition filled into a container using the filling method of the present disclosure described below.

[0017] In one or more embodiments, the containerized etching solution composition of the present disclosure may be a containerized etching solution composition containing at least an acid containing nitric acid and water.

[0018] (acid) In one or more embodiments, the acid contained in the containered etching liquid composition of the present disclosure is an acid containing at least nitric acid. The acid may be used alone (nitric acid only), or two or more types may be used in combination.

[0019] In one or more embodiments, the acid in the present disclosure may further include an acid other than nitric acid. From the viewpoint of uniform etching of the layer to be etched, the acid other than nitric acid is preferably at least one selected from inorganic acids such as sulfuric acid, hydrochloric acid, and phosphoric acid; and organic acids such as citric acid, formic acid, tartaric acid, oxalic acid, sulfamic acid, acetic acid, and malonic acid. From the viewpoint of uniform etching of the layer to be etched, the acid in the present disclosure is preferably a combination of an inorganic acid and an organic acid, and among these, a mixed acid consisting of phosphoric acid, acetic acid, and nitric acid is more preferred.

[0020] The amount of acid in the containered etching solution composition of the present disclosure is preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more, from the viewpoint of uniform etching of the layer to be etched. From the same viewpoint, it is preferably 98% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less. More specifically, the amount of acid in the containered etching solution composition of the present disclosure is preferably 70% by mass or more and 98% by mass or less, more preferably 75% by mass or more and 95% by mass or less, and even more preferably 80% by mass or more and 90% by mass or less. When two or more acids are used in combination, the amount of acid is the total amount of the acids.

[0021] When a mixed acid containing phosphoric acid, acetic acid, and nitric acid is used as the acid in the present disclosure, the amount of phosphoric acid in the mixed acid is preferably 50% by mass or more and 95% by mass or less, more preferably 55% by mass or more and 93% by mass or less, even more preferably 60% by mass or more and 90% by mass or less, still more preferably 70% by mass or more and 90% by mass or less, and even more preferably 80% by mass or more and 90% by mass or less, from the viewpoint of uniform etching of the layer to be etched. From the same viewpoint, the amount of acetic acid in the mixed acid is preferably 2% by mass or more and 80% by mass or less, more preferably 3% by mass or more and 70% by mass or less, even more preferably 5% by mass or more and 60% by mass or less, even more preferably 5% by mass or more and 50% by mass or less, even more preferably 5% by mass or more and 40% by mass or less, even more preferably 5% by mass or more and 30% by mass or less, even more preferably 5% by mass or more and 20% by mass or less, and even more preferably 5% by mass or more and 10% by mass or less. From the same viewpoint, the amount of nitric acid in the mixed acid is preferably 0.5% by mass or more and 20% by mass or less, more preferably 1% by mass or more and 15% by mass or less, even more preferably 1.5% by mass or more and 10% by mass or less, even more preferably 2% by mass or more and 8% by mass or less, and even more preferably 2% by mass or more and 6% by mass or less. In one or more embodiments of the present disclosure, the blending amount of each component in the mixed acid can be regarded as the content of each component in the mixed acid. The mass ratio of phosphoric acid to acetic acid to nitric acid (phosphoric acid / acetic acid / nitric acid) can be appropriately set.

[0022] (water) Examples of water contained in the container-packed etching solution composition of the present disclosure include distilled water, ion-exchanged water, pure water, and ultrapure water. The amount of water in the containered etching solution composition of the present disclosure is preferably 2% by mass or more, more preferably 5% by mass or more, even more preferably 7% by mass or more, and even more preferably 10% by mass or more, from the viewpoint of uniform etching of the layer to be etched, and from the same viewpoint, is preferably 30% by mass or less, more preferably 25% by mass or less, even more preferably 20% by mass or less, and even more preferably 15% by mass or less. More specifically, the amount of water in the containered etching solution composition of the present disclosure is preferably 2% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 25% by mass or less, even more preferably 7% by mass or more and 20% by mass or less, and even more preferably 10% by mass or more and 15% by mass or less.

[0023] (nitrogen-containing compounds) The containered etching solution composition of the present disclosure may further contain a nitrogen-containing compound. The nitrogen-containing compound is not particularly limited, but may be at least one selected from the group consisting of polyalkyleneimine, alkylamine, compound having an amino group and an ethylenically unsaturated double bond, polymer having a structural unit derived from a compound having an amino group and an ethylenically unsaturated double bond, alkanolamine, alicyclic amine, and polyalkylenepolyamine. Examples of the polyalkyleneimine include polyethyleneimine. Examples of the alkylamine include pentaethylenehexamine. Examples of the compound having an amino group and an ethylenically unsaturated double bond include allylamine and diallylamine. Examples of the polymer containing a structural unit derived from a compound having an amino group and an ethylenically unsaturated double bond include an allylamine polymer, a diallylamine polymer, a diallylamine / sulfur dioxide copolymer, a diallyldimethylammonium chloride polymer, and a diallyldimethylammonium chloride / sulfur dioxide copolymer. Examples of the alkanolamine include 2-(2-aminoethylamino)ethanol. The alicyclic amine may, for example, be N-(2-hydroxyethyl)piperazine. Examples of the polyalkylene polyamine include pentaethylenehexamine. Among these, from the viewpoints of suppressing discoloration of the container and uniformly etching the layer to be etched, the nitrogen-containing compound is preferably at least one selected from polyalkyleneimine, alkylamine, allylamine polymer, and diallylamine / sulfur dioxide copolymer, more preferably at least one selected from polyalkyleneimine and alkylamine, even more preferably polyalkyleneimine, and even more preferably polyethyleneimine. The nitrogen-containing compounds may be used alone or in combination of two or more.

[0024] When the nitrogen-containing compound is a polyalkyleneimine, its number-average molecular weight is preferably 300 or more, more preferably 600 or more, and even more preferably 1,200 or more from the viewpoint of uniform etching of the layer to be etched, and from the viewpoint of viscosity, it is preferably 100,000 or less, more preferably 5,000 or less, and even more preferably 3,000 or less. More specifically, the number-average molecular weight of the nitrogen-containing compound is preferably 300 or more and 100,000 or less, more preferably 600 or more and 5,000 or less, and even more preferably 1,200 or more and 3,000 or less. When the nitrogen-containing compound is a (co)polymer other than polyalkyleneimine, its weight-average molecular weight is preferably 2,000 or more, more preferably 3,000 or more, and even more preferably 4,000 or more from the viewpoint of uniform etching of the layer to be etched, and from the viewpoint of viscosity, it is preferably 50,000 or less, more preferably 10,000 or less, and even more preferably 7,000 or less. More specifically, the weight-average molecular weight of the nitrogen-containing compound is preferably 2,000 or more and 50,000 or less, more preferably 3,000 or more and 10,000 or less, and even more preferably 4,000 or more and 7,000 or less.

[0025] In the present disclosure, the average molecular weight can be measured, for example, by gel permeation chromatography (GPC). Examples of the measurement conditions include the following conditions. <GPC Conditions (Polyalkyleneimine)> Sample solution: Adjusted to a concentration of 0.1 wt%. Apparatus / Detector: HLC-8320GPC (Integrated GPC) manufactured by Tosoh Corporation Column: α-M + α-M (manufactured by Tosoh Corporation) Eluent: 0.15 mol / L Na2SO4, 1% CH3COOH / water Column temperature: 40 °C Flow rate: 1.0 mL / min Sample solution injection volume: 100 μL Standard polymer: Pullulan with known molecular weight (Shodex P-5, P-50, P-200, P-800) <GPC Conditions (Copolymers other than Polyalkyleneimine)> Sample solution: Adjusted to a concentration of 0.1 wt%. Detector: HLC-8320GPC (Integrated GPC) manufactured by Tosoh Corporation Column: α-M + α-M (manufactured by Tosoh Corporation) Eluent: 0.15 mol / L Na2SO4, 1% CH3COOH / water Column temperature: 40 °C Flow rate: 1.0 mL / min Sample solution injection volume: 100 μL Standard polymer: Pullulan with known molecular weight (Shodex P-5, P-50, P-200, P-800)

[0026] When the container-packed etching solution composition of the present disclosure contains a nitrogen-containing compound, the amount of the nitrogen-containing compound in the container-packed etching solution composition of the present disclosure is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of uniform etching of the layer to be etched. Furthermore, from the viewpoint of the solution viscosity and the liquid permeability during filtration, the amount is preferably 20% by mass or less, more preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less. More specifically, the amount of the nitrogen-containing compound in the container-packed etching solution composition of the present disclosure is preferably 0.1% by mass or more and 20% by mass or less, more preferably 0.5% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass or less, and even more preferably 1% by mass or more and 5% by mass or less. When two or more nitrogen-containing compounds are used in combination, the amount of the nitrogen-containing compound is the total content of the nitrogen-containing compounds.

[0027] (Other ingredients) The containered etching solution composition of the present disclosure may further contain other components, such as chelating agents, surfactants, solubilizing agents, preservatives, rust inhibitors, disinfectants, antibacterial agents, and antioxidants, as long as the effects of the present disclosure are not impaired.

[0028] In one or more embodiments, the containerized etching solution composition of the present disclosure preferably does not contain hydrogen peroxide. Here, in one or more embodiments, "free of hydrogen peroxide" includes not containing hydrogen peroxide, not substantially containing hydrogen peroxide, or not containing an amount of hydrogen peroxide that would affect the etching result. The specific amount of hydrogen peroxide in the containerized etching solution composition of the present disclosure is not particularly limited, but is preferably 3% by mass or less, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, even more preferably 0.01% by mass or less, even more preferably 0.001% by mass or less, and even more preferably 0% by mass.

[0029] (Number of particles in liquid) The number of particles having a particle diameter of 200 nm or more in the containered etching liquid composition of the present disclosure is preferably 0 particles / mL or more and 100 particles / mL or less, more preferably 0 particles / mL or more and 50 particles / mL or less, and even more preferably 0 particles / mL or more and 20 particles / mL or less. The number of particles having a particle diameter of 300 nm or more in the containered etching solution composition of the present disclosure is preferably 0 particles / mL or more and 50 particles / mL or less, more preferably 0 particles / mL or more and 20 particles / mL or less, and even more preferably 0 particles / mL or more and 10 particles / mL or less. The number of particles having a particle diameter of 500 nm or more in the containered etching solution composition of the present disclosure is preferably 0 particles / mL or more and 20 particles / mL or less, more preferably 0 particles / mL or more and 10 particles / mL or less, and even more preferably 0 particles / mL or more and 5 particles / mL or less. In one or more embodiments of the present disclosure, the particle size and number of particles in the liquid are measured using a liquid particle counter. In one or more embodiments, the particle size and number of particles in the liquid may be calculated by passing a predetermined amount of a treatment liquid through a predetermined filter and directly measuring or counting foreign matter (particles) captured on the filter surface using a microscope or the like.

[0030] (viscosity) From the viewpoint of liquid permeability during filtration, the viscosity of the containered etching solution composition of the present disclosure at 25°C is preferably 1 mPa·s or more, and preferably 200 mPa·s or less, more preferably 150 mPa·s or less, and even more preferably 100 mPa·s or less. More specifically, the viscosity of the containered etching solution composition of the present disclosure at 25°C is preferably 1 mPa·s or more and 200 mPa·s or less, more preferably 1 mPa·s or more and 150 mPa·s or less, and even more preferably 1 mPa·s or more and 100 mPa·s or less. In the present disclosure, the viscosity of the etching solution composition can be measured using a general-purpose viscometer such as a Brookfield viscometer or an Ubbelohde viscometer, and specifically, it can be measured by the method described in the examples.

[0031] (pH) From the viewpoint of uniform etching of the layer to be etched, the pH of the containered etching solution composition of the present disclosure is preferably 1 or less, more preferably 0 or less, even more preferably less than 0, and even more preferably about -1. The pH of the containered etching solution composition of the present disclosure can be -5 or more, or -3 or more. In the present disclosure, the pH of the etching solution composition is a value at 25°C and can be measured using a pH meter, specifically, by the method described in the Examples.

[0032] In the present disclosure, the term "amount of each component in the containered etching solution composition" refers, in one or more embodiments, to the amount of each component of the etching solution composition used in the etching step, i.e., at the time of starting use in the etching treatment (at the time of use). In one or more embodiments, the blending amount of each component in the container-packed etching solution composition of the present disclosure can be considered to be the content of each component in the container-packed etching solution composition of the present disclosure. However, if there is an effect of neutralization, the blending amount and the content may differ.

[0033] The containerized etching liquid composition according to the present disclosure may be a so-called one-component type in which all components are premixed and supplied to the market, or may be a so-called two-component type in which components are mixed at the time of use.

[0034] The containered etching solution composition of the present disclosure may be stored and supplied in a concentrated state as long as its stability is not impaired. This is preferable in that production and transportation costs can be reduced. The concentrated solution can then be used in the etching process after being appropriately diluted with water or an aqueous acid solution, as needed. The dilution ratio can be, for example, 5 to 100 times.

[0035] (layer to be etched) The containered etching solution composition of the present disclosure is used for etching a layer to be etched that contains at least one metal. The metal contained in the layer to be etched is preferably at least one metal selected from tungsten, tantalum, zirconium, hafnium, molybdenum, niobium, ruthenium, osmium, rhenium, rhodium, copper, nickel, cobalt, titanium, titanium nitride, alumina, aluminum, and iridium. In one or more embodiments, the etching solution composition of the present disclosure is suitable for use in etching a tungsten film, a niobium film, a tantalum film, a zirconium film, or a molybdenum film.

[0036] (container) In one or more embodiments, the container filled with the etching solution composition may be a resin container. Examples of resin containers include containers made of polyethylene resin or polypropylene resin, and containers made of fluororesin. Examples of the polyethylene resin include low-density polyethylene, medium-density polyethylene, high-density polyethylene, and mixtures thereof. Examples of the fluororesin include polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkane (PFA). As the filling container, containers made of polyethylene or polypropylene resin, which are inexpensive from the viewpoint of production cost, are preferred. In the present disclosure, the term "polyethylene resin or polypropylene resin container" refers to a container in which at least the portion of the container that comes into contact with the etching solution composition is made of polyethylene resin or polypropylene resin. As the resin container in the present disclosure, for example, a container may be used in which a polyethylene resin or polypropylene resin layer is provided as an inner layer that comes into contact with the etching solution composition and another resin or the like is laminated on the outer surface thereof. Commercially available polyethylene resin or polypropylene resin containers generally contain an antistatic agent such as a surfactant or a metal oxide, but the etching solution composition of the present disclosure preferably does not contain an antistatic agent. Furthermore, since the etching solution composition of the present disclosure contains nitric acid as an essential component, in order to prevent decomposition due to sunlight or the like, it is preferable that the container exterior be colored or light-shielding, such as gray or blue, rather than a translucent or white container. Examples of the form of the resin container in the present disclosure include a resin container with a capacity of 0.1 to 30 L, a composite container combining a resin inner container with a capacity of 0.1 to 30 L with cardboard, a composite container combining a resin inner container with a capacity of 1 to 30 L with a metal can, a resin drum container with a capacity of 20 to 300 L, a composite container combining a resin inner container with a capacity of 20 to 300 L with a metal drum, and a composite container combining a resin inner container with a capacity of 500 to 1200 L with a metal container.

[0037] (Filling System) In one or more embodiments, the containerized etching solution composition of the present disclosure is an etching solution composition filled into a container 6 using a filling system such as that shown in Fig. 1. Examples of the container 6 include the containers described above. 1 , in one or more embodiments, the filling system of the present disclosure includes a tank 1 that stores an etching solution composition, a pump 2 that delivers the etching solution composition, a filter 3 that filters the etching solution composition, an outlet valve 4 that controls the flow rate of the etching solution composition discharged from an outlet 5, and a pipe P1 that connects the tank 1, the pump 2, the filter 3, the outlet valve 4, and the outlet 5, and further includes a circulation path P2 that branches off from the pipe P1 between the filter 3 and the outlet valve 4 and connects to the upstream side of the pump 2. In one or more embodiments, the filling system of the present disclosure further includes a circulation valve 7 that controls the flow rate of the etching solution composition circulated through the circulation path P2. In one or more embodiments, the filling system of the present disclosure is configured to pump an etching solution composition in a tank 1 with a pump 2, filter it with a filter 3, open an outlet valve 4, discharge the etching solution composition from an outlet 5, fill a container 6, and circulate the etching solution composition through a circulation path P2 by opening a circulation valve 7 whether the outlet valve 4 is open or closed. In one or more embodiments of the filling system of the present disclosure, the flow rate of the etching solution composition circulating through the circulation path P2 is adjusted to 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path P2 and the flow rate of the etching solution composition discharged from the outlet 5.

[0038] From the viewpoint of reducing the number of particles in the liquid, the flow rate of the etching solution composition circulated through the circulation path P2 (hereinafter also referred to as the "circulation flow rate") is preferably adjusted to 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet, more preferably 20% or more, and even more preferably 50% or more.

[0039] (pump) The pump 2 is a pump that sends the etching solution composition in the tank 1 into the pipe P1. The type of the pump is not particularly limited, and examples thereof include a diaphragm pump. The pump 2 stops when both the circulation valve 7 and the outlet valve 4 are closed.

[0040] (filter) The filter 3 is a filter that filters the etching solution composition. Examples of the filter 3 include conventionally used pleated filters, depth filters, and filter aid-containing filters, and these can be used in combination. From the viewpoint of reducing the number of particles in the liquid, a pleated filter is preferred, and a combination of a depth filter and a pleated filter is more preferred, and a filter aid-containing filter may also be combined. In one or more embodiments, when a filter aid-containing filter is used, it is preferable to provide a pleated filter in the subsequent stage. Pleated filters generally use a hollow cylindrical cartridge-type filter formed by shaping a filter material into a pleated shape (Advantec Toyo, Nippon Pall, CUNO, Daiwabo, 3M, Entegris, Cobetter, etc.). Unlike depth filters, which capture particles at various locations in the thickness direction, pleated filters have a thin filter material and are said to mainly capture particles on the filter surface, and are generally characterized by high filtration accuracy. Pleated filters may be used in a single stage or in multiple stages (e.g., arranged in series). Specific examples of depth filters include bag-type filters (Sumitomo 3M, etc.) and cartridge-type filters (Advantec Toyo, Nippon Pall, CUNO, Daiwabo, etc.). Depth filters are characterized by a pore structure in which the pores are coarse at the inlet side and fine at the outlet side, and the pores become finer continuously or stepwise from the inlet side to the outlet side. Therefore, larger particles are captured near the inlet side, and smaller particles are captured near the outlet side. Depth filters can be shaped like a bag or a hollow cylindrical cartridge. Filter materials with the above characteristics simply formed into pleats are classified as depth filters because they function as depth filters. Depth filters can be used in a single stage or in multiple stages (e.g., in a direct arrangement). Filters with different pore sizes can also be combined in multiple stages in descending order of pore size. Furthermore, bag-type and cartridge-type filters can be used in combination. The filter aid-containing filter is a filter containing a filter aid. Examples of the filter aid include insoluble mineral substances such as silicon dioxide, kaolin, acid clay, diatomaceous earth, perlite, bentonite, and talc. Among the filter aids, silicon dioxide, diatomaceous earth, and perlite are preferred from the viewpoint of improving dispersibility, with diatomaceous earth and perlite being more preferred, and diatomaceous earth being even more preferred. The filter aid-containing filter can contain the filter aid on either or both the filter surface and the inside of the filter.

[0041] From the viewpoints of productivity and filter life extension, the filter pore size is preferably 5 nm or more, more preferably 10 nm or more, and even more preferably 20 nm or more, and from the viewpoint of reducing the number of particles in the liquid, it is preferably 200 nm or less, more preferably 100 nm or less, and even more preferably 50 nm or less. More specifically, the filter pore size is preferably 5 nm or more and 200 nm or less, more preferably 10 nm or more and 100 nm or less, and even more preferably 20 nm or more and 50 nm or less.

[0042] The number of stages of the filter 3 is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1 or 2, from the viewpoint of reducing the number of particles in the liquid.

[0043] 1, the circulation path P2 is configured to connect the downstream side of the filter 3 and the tank 1, but is not limited to this as long as it can connect the downstream side of the filter 3 and the upstream side of the pump 2. For example, the circulation path P2 may be configured to return from the downstream side of the filter 3 to the piping P1 between the tank 1 and the pump 2. In addition, in FIG. 1, the outlet valve 4 and the circulation valve 7 are provided separately, but instead of these two valves, a three-way valve may be provided at the branch point of the pipe P1 and the circulation path P2 to switch the flow path of the etching solution composition.

[0044] [Filling method] In one aspect, the present disclosure relates to a method for filling a container with an etching solution composition for etching a layer to be etched that contains at least one metal (hereinafter also referred to as the "filling method of the present disclosure"). In one or more embodiments, the filling method of the present disclosure is a filling apparatus including: a tank for storing an etching solution composition; a pump that is provided downstream of the tank and delivers the etching solution composition; a filter that is provided downstream of the pump and filters the etching solution composition; an outlet valve that is provided downstream of the filter and controls the flow rate of the etching solution composition discharged from an outlet; piping that connects the tank, the pump, the filter, the outlet valve, and the outlet; a circulation path that branches off from the piping between the filter and the outlet valve and connects to the upstream side of the pump; and a circulation valve that controls the flow rate of the etching solution composition circulating through the circulation path. The system includes a step of pumping the etching solution composition in a tank and filtering it through a filter (hereinafter also referred to as the "filtration step"), and a step of opening an outlet valve and discharging the etching solution composition from the outlet into a container (hereinafter also referred to as the "filling step"), and further includes a step of opening a circulation valve while the outlet valve is open or closed and circulating the etching solution composition through a circulation path (hereinafter also referred to as the "circulation step"), in which the flow rate of the etching solution composition circulating through the circulation path is adjusted to 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet. According to the filling method of the present disclosure, the number of particles in the etching solution composition filled in the container can be reduced.

[0045] In one or more embodiments, the filling method of the present disclosure can be carried out using a filling system as shown in Fig. 1. Details of the filling system shown in Fig. 1 have been described above.

[0046] <Filtration process> In one or more embodiments, the filling method of the present disclosure includes a step (a filtration step) of pumping the etching solution composition in the tank 1 with a pump 2 and filtering it with a filter 3. Examples of the pump 2 and the filter 3 include those described above.

[0047] (Pre-filtration etching solution composition) In one or more embodiments, the components and their contents contained in the etching solution composition in the tank 1 (hereinafter also referred to as the "pre-filtration etching solution composition") can be the same as those of the containerized etching solution composition of the present disclosure described above. In one or more embodiments, the pH and viscosity of the pre-filtered etching solution composition can be similar to those of the containerized etching solution composition of the present disclosure described above.

[0048] (Method of producing pre-filtered etching solution composition) In one or more embodiments, the pre-filtration etching solution composition can be obtained by blending a nitric acid-containing acid, water, and, if desired, the optional components (nitrogen-containing compound, other components) described above using a known method. Therefore, in one aspect, the present disclosure relates to a method for producing an etching solution composition (hereinafter also referred to as the "etching solution production method of the present disclosure"), which includes blending at least a nitric acid-containing acid and water. In one or more embodiments, the phrase "blending at least a nitric acid-containing acid and water" in the present disclosure includes simultaneously or sequentially mixing a nitric acid-containing acid, water, and, if necessary, the optional components (nitrogen-containing compound, other components). The order of mixing is not particularly limited. The blending can be performed using a mixer such as a homomixer, homogenizer, ultrasonic disperser, or wet ball mill. The preferred amounts of each component in the etching solution production method of the present disclosure can be the same as the preferred amounts of each component in the containerized etching solution composition of the present disclosure.

[0049] In the present disclosure, pressure fluctuations may occur between the upstream and downstream sides of the filter due to the opening and closing operation of the outlet valve 4. From the viewpoint of reducing the number of particles in the liquid, when the pressure on the upstream side of the filter while the outlet valve 4 is open is defined as A, the pressure on the downstream side is defined as B, and when the pressure on the upstream side of the filter while the outlet valve 4 is closed (i.e., when filling of the etching solution composition into the container is stopped), is defined as A', and the pressure on the downstream side is defined as B', it is preferable to satisfy the following condition (1), and it is more preferable to satisfy the following condition (2). (1) A>B, A´>B´ (2)AB≧0.01MPa, A´-B´≧0.01MPa

[0050] From the viewpoint of productivity, the filtration flow rate in the filtration step is preferably 0.1 kg / (m 2 ·min) or more, more preferably 1kg / (m 2 ·min) or more, more preferably 3 kg / (m 2 ·min) or more, and from the viewpoint of reducing the number of particles in the liquid, it is preferably 30 kg / (m 2 ·min) or less, more preferably 20 kg / (m 2 ·min) or less, more preferably 15 kg / (m 2 More specifically, the filtration flow rate is preferably 0.1 kg / (m 2 · min) or more 30kg / (m 2 ·min) or less, more preferably 1 kg / (m 2 · min) or more 20kg / (m 2 ·min) or less, more preferably 3 kg / (m 2 ·min) or more than 15kg / (m 2 10 min) or less. In the present disclosure, the "filtration flow rate" refers to the weight of filtered material per unit area per time, and in one or more embodiments, this can be adjusted by adjusting the pump pressure or the degree of opening of the circulation valve. When multiple filters are used for filtration, the "filtration flow rate" refers to the weight of filtered material per unit area per time calculated from the sum of the areas of all the filters used.

[0051] The pressure of the pump 2 (hereinafter also referred to as "filtration pressure") is preferably 0.01 MPa or more and 5 MPa or less, more preferably 0.1 MPa or more and 1 MPa or less, and even more preferably 0.2 MPa or more and 0.5 MPa or less, from the viewpoints of productivity and reducing the number of particles in the liquid. In one or more embodiments, the filtration pressure can be adjusted by adjusting the output pressure with a regulator.

[0052] The filtration method may be a circulation method in which filtration is repeated, or a single-pass method. Alternatively, a batch method in which single-pass methods are repeated may be used. As a liquid passing method, a pump is preferably used in the circulation method to apply pressure, and in the single-pass method, in addition to using a pump, a pressure filtration method in which air pressure or the like is introduced into the tank to reduce fluctuations in the filter inlet pressure may be used.

[0053] <Filling process> In one or more embodiments, the filling method of the present disclosure includes a step of opening the outlet valve 4 and discharging the etching solution composition from the outlet 5 into the container 6 (filling step).

[0054] The flow rate of the etching solution composition discharged from the outlet 5 (hereinafter also referred to as the "filling flow rate") can be controlled by adjusting the aperture of the outlet valve 4. The aperture of the outlet valve 4 may be adjusted manually, or may be automatically adjusted by providing a control unit. The flow rate of the etching solution composition in the filling step is, for example, 0.1 to 30 kg / (m 2 -minutes) can be set.

[0055] <Circulation process> In one or more embodiments, the filling method of the present disclosure includes a step (circulation step) of opening the circulation valve 7 while the outlet valve 4 is open or closed, and circulating the etching solution composition through the circulation path P2.

[0056] The flow rate (circulation flow rate) of the etching solution composition circulated through the circulation path P2 can be controlled by adjusting the opening of the circulation valve 7. The opening of the circulation valve 7 may be adjusted manually, or may be automatically adjusted by providing a control unit. From the viewpoint of reducing the number of particles in the liquid, the circulation flow rate of the etching solution composition in the circulation step is preferably adjusted to 10% or more, more preferably 20% or more, and even more preferably 50% or more, of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet. The circulation flow rate of the etching solution composition in the circulation step is, for example, 0.1 to 30 kg / (m2 -minutes) can be set. In the present disclosure, the ratio of the circulation flow rate when the circulation valve is partially opened to the sum of the flow rate flowing through the circulation path and the flow rate discharged from the outlet is also referred to as the "opening degree of the circulation valve."

[0057] In one or more embodiments, the filling method of the present disclosure may be configured to close the circulation valve 7 when the amount of the etching solution composition in the tank 1 falls below a predetermined amount, or when filling of the etching solution composition into all of the multiple containers 6 has been completed.

[0058] <Etching solution composition filled in a container> In one or more embodiments, the amount of each component contained in the etching solution composition filled in the container 6, i.e., the etching solution composition after filtration, can be the same as that in the etching solution composition before filtration. Examples of the container 6 include the containers described above.

[0059] In one or more embodiments, the number of particles in the etching solution composition filled in the container 6 is preferably the same as the number of particles in the etching solution composition of the present disclosure described above.

[0060] [Method of manufacturing container-packed etching solution composition] In one or more embodiments, the filling method of the present disclosure is used to fill a container with an etching solution composition. Thus, in one aspect, the present disclosure relates to a method for producing a container-packed etching solution composition, in which the filling method of the present disclosure is used to produce an etching solution composition packed in a container. According to the production method of the present disclosure, a container-packed etching solution composition with a reduced number of particles in the liquid can be produced. [Example]

[0061] Hereinafter, the present disclosure will be described in more detail with reference to examples, but these are merely illustrative examples and the present disclosure is not limited to these examples.

[0062] 1. Preparation of Etching Solution Compositions A to C Etching solution compositions A to C were prepared by blending phosphoric acid, nitric acid, acetic acid, a nitrogen-containing compound shown in Table 1, and water. The blending amount (mass %, active content) of each component in the prepared etching solution compositions is shown in Table 1.

[0063] The components used to prepare etching solution compositions A to C were as follows. (acid) Phosphoric acid [Rinkagaku Kogyo Co., Ltd.] Nitric acid [FUJIFILM Wako Pure Chemical Corporation] Acetic acid [Fujifilm Wako Pure Chemical Corporation] (nitrogen-containing compounds) Polyethyleneimine [number average molecular weight 1800, "Epomin SP-018" manufactured by Nippon Shokubai Co., Ltd.] (water) Water [ultrapure water produced using a continuous pure water production system (Pure Conti PC-2000VRL) and a subsystem (MacAce KC-05H) manufactured by Kurita Water Industries Ltd.]

[0064] [Table 1]

[0065] 2. Preparation of container-packed etching solution composition The prepared etching solution compositions A to C were filled into containers under the following conditions using the filling system shown in FIG. 1, to obtain container-packed etching solution compositions of Examples 1 to 7 and Comparative Examples 1 to 6. In Examples 1 to 7, the etching solution composition in tank 1 was pumped by pump 2 and filtered for 60 minutes through filter 3 via circulation path P2. Thereafter, circulation valve 7 was adjusted to the opening shown in Table 2 to adjust the circulation flow rate of the etching solution composition. While maintaining the opening of circulation valve 7, outlet valve 4 was opened, and 5 kg of the composition was cut off and sampled from outlet 5. In Comparative Examples 1 to 3, the etching solution composition in tank 1 was pumped by pump 2 and filtered for 60 minutes through filter 3 via circulation path P2. Thereafter, circulation valve 7 was closed to stop pump 2 before opening outlet valve 4, and then outlet valve 4 was opened to cut off 5 kg of the solution, which was then sampled from outlet 5. In Comparative Examples 4 to 6, the etching solution composition in tank 1 was pumped by pump 2 and filtered for 60 minutes through circulation path P2 with filter 3. Thereafter, circulation valve 7 was closed and outlet valve 4 was gradually opened at the same time so that the sum of the flow rate through circulation path P2 and the flow rate discharged from outlet valve 4 was always constant, and sampling was carried out from outlet 5 after outlet valve 4 was fully opened. <Filling system> Pump 2: Diaphragm pump DP-10BPT (Yamada Corporation) Piping P1, P2: Corrugated flexible hose 15A (Flon Chemical Co., Ltd.) Filter 3: Fluoroguard FP CWEX010V1 (Entegris, 20 nm) Container 6: 20L container (polyethylene can (color: gray), manufactured by Kodama Resin Industry) <Condition> Filtration pressure: 0.3 MPa (see Table 1) Filtration flow rate: 10 kg / (m 2 min) Scale: 300 kg of etching solution composition Sampling: Circulation filtration was carried out for 60 minutes in circulation route P2, and sampling was carried out after cutting off 5 kg from outlet 5 Filling flow rate: 9, 5, 2kg / (m 2 ·min) Circulation flow rate: 1, 5, 8kg / (m 2 ·min)

[0066] 3.Measuring methods for various parameters [pH of etching solution composition] The pH value of the etching solution composition at 25° C. was measured using a pH meter (manufactured by DKK-Toa Corporation), and was the value measured one minute after the electrode of the pH meter was immersed in the etching solution.

[0067] [Viscosity of Etching Solution Composition] The viscosity of the etching solution was measured using the following viscometer under the following conditions. Device name: TVB-10 viscometer (with thermostatic bath) manufactured by Toki Sangyo Co., Ltd. Rotor: Spindle No. M1, Cord No. 20 Rotation speed: 100 rpm, viscosity measured after 60 seconds Measurement temperature: 25℃

[0068] [Circulation valve opening] The opening of the circulation valve was calculated using the following formula. Circulation valve opening (%) = (circulation flow rate when the circulation valve is partially opened / total flow rate through the circulation path P2 and the flow rate discharged from the outlet 5) × 100

[0069] 4. Evaluation [Number of particles in liquid] The number of particles in the etching solution composition was measured using the following particle counter under the following conditions. Device name: RION KS-42B Injection volume: 10mL Injection rate: 10mL / min

[0070] [Table 2]

[0071] As shown in Table 2, it was found that Examples 1 to 7, in which the opening degree of the circulation valve was 10% or more while the outlet valve was open and closed, had a reduced number of particles in the liquid compared to Comparative Examples 1 to 3, in which the opening degree of the circulation valve was 0% while the outlet valve was open, and Comparative Examples 4 to 6, in which the circulation valve opened when the outlet valve was closed. [Industrial Applicability]

[0072] The containered etching solution composition of the present disclosure is useful, for example, in a method for producing a large-capacity semiconductor memory. [Explanation of symbols]

[0073] 1...tank, 2...pump, 3...filter, 4...outlet valve, 5...outlet, 6...container, 7...circulation valve, P1...piping, P2...piping (circulation path), A...particle

Claims

1. A container-packed etching solution composition for etching a layer to be etched that contains molybdenum, the container being filled with the etching solution composition, the number of particles in the container having a particle diameter of 200 nm or more is 0 particles / mL or more and 100 particles / mL or less, the number of particles in the container having a particle diameter of 300 nm or more is 0 particles / mL or more and 50 particles / mL or less, and the number of particles in the container having a particle diameter of 500 nm or more is 0 particles / mL or more and 20 particles / mL or less; and A containerized etching solution composition comprising polyethyleneimine.

2. 2. The container-packed etching solution composition according to claim 1, wherein the container-packed etching solution composition comprises an acid containing at least nitric acid and water, and has a pH of 1 or less.

3. 3. The container-packed etching solution composition according to claim 1, wherein the container-packed etching solution composition has a viscosity at 25°C of 1 mPa·s or more and 200 mPa·s or less.

4. A method for filling a container with an etching solution composition for etching a layer to be etched, the etching solution composition comprising at least one metal, the method comprising the steps of: a step of pumping the etching solution composition in the tank and filtering it using a filling system comprising: a tank for storing the etching solution composition; a pump provided downstream of the tank for pumping the etching solution composition; a filter provided downstream of the pump for filtering the etching solution composition; an outlet valve provided downstream of the filter for controlling the flow rate of the etching solution composition discharged from an outlet; piping connecting the tank, the pump, the filter, the outlet valve, and the outlet; a circulation path branching from the piping between the filter and the outlet valve and connecting to the upstream side of the pump; and a circulation valve for controlling the flow rate of the etching solution composition circulating through the circulation path; a step of opening an outlet valve and filling a container with the etching solution composition discharged from the outlet, The method further includes a step of opening the circulation valve while the outlet valve is open and while the outlet valve is closed, and circulating the etching solution composition through the circulation path; The flow rate of the etching solution composition circulating through the circulation path is adjusted to 10% or more of the sum of the flow rate of the etching solution composition circulating through the circulation path and the flow rate of the etching solution composition discharged from the outlet.

5. 5. The filling method according to claim 4, wherein the following condition (1) is satisfied, when the pressure on the upstream side of the filter while the outlet valve is open is A, the pressure on the downstream side is B, and the pressure on the upstream side of the filter while the outlet valve is closed is A', and the pressure on the downstream side is B'. (1) A>B, A'>B'

6. 6. The filling method according to claim 4 or 5, wherein the following condition (2) is satisfied, when the pressure on the upstream side of the filter while the outlet valve is open is A, the pressure on the downstream side is B, and the pressure on the upstream side of the filter while the outlet valve is closed is A', and the pressure on the downstream side is B': (2) A-B≧0.01MPa, A′-B′≧0.01MPa

7. 7. The method according to claim 4, wherein the circulation path connects the downstream side of the filter with the tank.

8. A method for producing a container-packed etching solution composition, comprising producing an etching solution composition packed in a container using the filling method according to any one of claims 4 to 7.

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