pH / oxidation-reduction potential adjusted water manufacturing device, pH / oxidation-reduction potential adjusted water manufacturing method and semiconductor device manufacturing method

Abstract

To provide a pH / oxidation-reduction potential adjusted water producing device for producing pH / oxidation-reduction potential adjusted water that can be used as cooling water for dicing blade, making it possible to reduce a frequency of replacing dicing blades.SOLUTION: A pH / oxidation-reduction potential adjusted water producing device 1 includes: a degassing membrane device 5 having a degassing membrane for removing a gas dissolved as an impurity from pure water; a pH adjusting device 4 for adjusting pH of the pure water; and a dissolving membrane device 6 having a gas dissolving membrane for dissolving an inert gas in the pure water, thereby producing pH / oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an apparatus for producing pH / oxidation-reduction potential adjusted water, a method for producing pH / oxidation-reduction potential adjusted water, and a method for producing a semiconductor device. [Background technology]

[0002] Among the semiconductor manufacturing processes, the dicing process is one of the post-processes used to assemble semiconductor chips. The dicing process involves cutting a semiconductor substrate on which numerous integrated circuits (ICs) are formed into individual ICs to produce IC chips. In the dicing process, for example, the semiconductor substrate after the integrated circuits have been formed is attached to dicing tape, the semiconductor substrate is cut into individual ICs, and then individual IC chips are produced through a series of steps, including cleaning, removal of the dicing tape, and extraction of the semiconductor chips.

[0003] Known methods for cutting semiconductor substrates include blade dicing and laser ablation dicing. Blade dicing is a method in which an extremely thin blade called a dicing blade is rotated at high speed to cut the semiconductor substrate. Laser ablation dicing is a method in which a high-energy laser is irradiated to partially evaporate and sublimate the semiconductor substrate, cutting it. Of these, blade dicing is considered the most common method.

[0004] When blade dicing separates integrated circuits arranged on a semiconductor substrate, friction between the dicing blade and the semiconductor substrate generates heat and chips. Therefore, blade dicing is typically performed while spraying cooling water to suppress heat generation and remove chips. Pure water or carbonated water is used as the cooling water. Pure water has a high resistivity, which can cause charging of the substrate and electrostatic breakdown of devices due to friction between the dicing blade and the semiconductor substrate. Therefore, carbonated water, which has a lower resistivity due to the dissolution of carbon dioxide gas in pure water, is more commonly used.

[0005] The dicing blade used in blade dicing is a disc-shaped blade about 15 μm thick, with diamond abrasive grains fixed to the outer edge surface with a binder. Metals such as nickel, cobalt, copper, tin, silver, and tungsten are used as binders for diamond abrasive grains. Dicing blades are used repeatedly in the dicing process, and as use causes physical wear around the outer edge surface of the blade, leading to a decrease in dicing performance, so they are periodically replaced or discarded.

[0006] However, deterioration of dicing blade performance is not limited to physical factors such as wear. Carbonated water, which is a weak acid used as cooling water during dicing, dissolves various metals that serve as binders. Therefore, in addition to wear, there is also concern about deterioration of dicing performance due to the consumption of binders. Therefore, the use of carbonated water as cooling water is one of the factors that increases the frequency of dicing blade replacement. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2022-78489 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the above circumstances, and its objective is to provide a manufacturing apparatus for producing pH / oxidation-reduction potential adjusted water as cooling water for blade dicing, which can reduce the frequency of dicing blade replacement, a manufacturing method for pH / oxidation-reduction potential adjusted water, and a manufacturing method for semiconductor devices. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention employs the following configuration. [1] A degassing membrane device having a degassing membrane that removes gases dissolved as impurities from pure water; A pH adjuster that adjusts the pH of pure water; a dissolving film device having a gas dissolving film that dissolves an inert gas in pure water; This pH / oxidation-reduction potential adjusted water manufacturing device produces pH / oxidation-reduction potential adjusted water with an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at pH 9-14 and 25°C. [2] The pH adjusting device, the degassing membrane device, and the dissolving membrane device are arranged in this order along the direction of flow of pure water; The pH / oxidation-reduction potential adjusted water producing apparatus according to [1], wherein the pH adjusting device adds a liquid pH adjuster to the pure water. [3] The pH / oxidation-reduction potential adjusted water producing apparatus according to [2], wherein the pH adjuster is an aqueous solution of at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine. [4] The degassing membrane device and the dissolving membrane device are arranged in this order along the direction of flow of pure water, the pH adjusting device supplies a gaseous pH adjusting agent to the gas dissolution film of the dissolution film device; The pH / oxidation-reduction potential adjusted water producing apparatus according to [1], wherein the dissolving film device dissolves at least the pH adjuster in the pure water. [5] The pH / oxidation-reduction potential adjusted water producing apparatus according to [4], wherein the pH adjuster is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine. [6] The pH / oxidation-reduction potential adjusted water producing apparatus according to [5], wherein the pH adjuster further contains an inert gas. [7] A degassing membrane device equipped with a degassing membrane that removes gases dissolved as impurities from pure water; A pH adjusting device for adjusting the pH of the pure water; This pH / oxidation-reduction potential adjusted water manufacturing device produces pH / oxidation-reduction potential adjusted water with an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at pH 9-14 and 25°C. [8] The degassing membrane device and the pH adjusting device are arranged in this order along the direction of flow of pure water, The pH / oxidation-reduction potential adjusted water producing apparatus according to [7], wherein the pH adjuster dissolves at least one pH adjuster selected from a gas and a liquid in the pure water. [9] The pH / oxidation-reduction potential adjusted water producing apparatus according to [7], wherein the pH adjuster is an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine and trimethylamine.

[10] The pH / oxidation-reduction potential adjusted water producing apparatus according to [7], wherein the pH adjuster comprises at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas.

[11] An apparatus for producing pH / oxidation-reduction potential adjusted water according to any one of [1] to

[10] , which produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at 25°C, and a dissolved oxygen concentration of 50 ppb or less at 25°C.

[12] A pH / oxidation-reduction potential adjusted water manufacturing apparatus according to any one of [1] to

[10] , which produces pH / oxidation-reduction potential adjusted water having a redox potential at pH 9 to 14 and 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) and a hydrogen peroxide concentration of 30 ppb or less.

[13] A pH / oxidation-reduction potential adjusted water manufacturing apparatus according to any one of [1] to

[10] , which produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential at 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl), a dissolved oxygen concentration at 25°C of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less.

[14] A pH / oxidation-reduction potential adjusted water manufacturing apparatus according to any one of [1] to

[10] , wherein a hydrogen peroxide removal mechanism for removing hydrogen peroxide dissolved as an impurity from pure water is provided upstream of the degassing membrane device.

[15] A pH / oxidation-reduction potential adjusted water manufacturing apparatus according to any one of [1] to

[10] , which is provided with a supply flow path for supplying the produced pH / oxidation-reduction potential adjusted water as cooling water for a dicing blade having diamond abrasive grains fixed thereto by a binder containing at least one selected from the group consisting of nickel, cobalt, copper, tin, silver, tungsten, and iron.

[16] A pH / oxidation-reduction potential adjusted water manufacturing apparatus according to any one of [1] to

[10] , comprising a supply flow path for supplying the manufactured pH / oxidation-reduction potential adjusted water as cooling water in a dicing process in a semiconductor manufacturing process.

[17] A pH adjustment step of adjusting the pH of the pure water by adding a liquid pH adjuster to the pure water; a degassing step in which gases dissolved as impurities are removed from the pure water using a degassing membrane; This is followed by a gas dissolution process in which an inert gas is dissolved in pure water using a gas dissolution membrane. A method for producing pH / oxidation-reduction potential adjusted water, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and at 25°C.

[18] A method for producing pH / oxidation-reduction potential adjusted water according to

[17] , wherein the pH adjuster is an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine and trimethylamine.

[19] A degassing process in which gases dissolved as impurities in the pure water are removed from the pure water using a degassing membrane; and a step of supplying a gaseous pH adjuster to the pure water using a gas-dissolved membrane to adjust the pH of the pure water. A method for producing pH / oxidation-reduction potential adjusted water, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and at 25°C.

[20] The method for producing pH / oxidation-reduction potential adjusted water according to

[19] , wherein the pH adjuster is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine.

[21] The method for producing pH / oxidation-reduction potential adjusted water according to

[20] , wherein the pH adjuster further contains an inert gas.

[22] A degassing process in which gases dissolved as impurities in the pure water are removed from the pure water using a degassing membrane; and a pH adjusting step of adjusting the pH of the pure water by adding at least one pH adjuster selected from a gas and a liquid to the pure water, A method for producing pH / oxidation-reduction potential adjusted water, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and at 25°C.

[23] A method for producing pH / oxidation-reduction potential adjusted water according to

[22] , wherein the pH adjuster is an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine and trimethylamine.

[24] The method for producing pH / oxidation-reduction potential adjusted water according to

[22] , wherein the pH adjuster comprises at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas.

[25] A method for producing pH / oxidation-reduction potential adjusted water according to any one of

[17] to

[24] , which produces pH / oxidation-reduction potential adjusted water having a redox potential at pH 9 to 14 and 25°C of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) and a dissolved oxygen concentration at 25°C of 50 ppb or less.

[26] A method for producing pH / oxidation-reduction potential adjusted water according to any one of

[17] to

[24] , which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at pH 9 to 14 and 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) and a hydrogen peroxide concentration of 30 ppb or less.

[27] A method for producing pH / oxidation-reduction potential adjusted water according to any one of

[17] to

[24] , which produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, a dissolved oxygen concentration of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less at 25°C.

[28] The method for producing pH / oxidation-reduction potential adjusted water according to

[17] , further comprising a hydrogen peroxide removal step of removing hydrogen peroxide dissolved as an impurity in the pure water from the pure water prior to the pH adjustment step.

[29] A method for producing pH / oxidation-reduction potential adjusted water according to

[19] or

[22] , wherein a hydrogen peroxide removal step is carried out before the degassing step to remove hydrogen peroxide dissolved as an impurity in the pure water from the pure water.

[30] A method for manufacturing a semiconductor device, in which the pH / oxidation-reduction potential adjusted water produced by the method for producing pH / oxidation-reduction potential adjusted water described in any one of

[17] to

[24] is used as cooling water for a dicing blade in which diamond abrasive grains are fixed by a metal layer containing at least one selected from the group consisting of nickel, cobalt, copper, tin, silver, tungsten and iron.

[31] A method for manufacturing a semiconductor device, in which the pH / oxidation-reduction potential adjusted water manufactured by the method for manufacturing pH / oxidation-reduction potential adjusted water described in any one of

[17] to

[24] is used as cooling water in a dicing process of a semiconductor manufacturing process. [Effects of the Invention]

[0010] The apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention can produce pH / oxidation-reduction potential adjusted water with a low concentration of dissolved gases, an adjusted pH of 9 to 14, and stabilized pH and oxidation-reduction potential by dissolving an inert gas. Such pH / oxidation-reduction potential adjusted water can suppress dissolution of various metals that make up the binder of dicing blades. Therefore, the present invention can provide an apparatus for producing pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing, which can reduce the frequency of dicing blade replacement.

[0011] The pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention adjusts the pH of pure water using a pH adjustment device that adds a liquid pH adjuster to the pure water, removes dissolved gases in the pure water using a degassing membrane device, and dissolves an inert gas in the pure water using a dissolution membrane device.By using a liquid pH adjuster, the pH of the pure water does not fluctuate even when it is degassed after pH adjustment, so it is possible to produce pH / oxidation-reduction potential adjusted water with stabilized pH and oxidation-reduction potential.

[0012] According to the apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention, the pH adjustment device adds at least one aqueous solution selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine to pure water as a pH adjuster, thereby making it possible to adjust the pH of the pH / oxidation-reduction potential adjusted water to a range of 9 to 14.

[0013] The pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention removes dissolved gases from pure water using a degassing membrane device, supplies a gaseous pH adjuster to a gas dissolution device using a pH adjustment device, and adds the gaseous pH adjuster to the pure water using the gas dissolution device.Since the pH is adjusted for pre-degassed pure water, the pH of the pure water does not fluctuate, and pH / oxidation-reduction potential adjusted water with stabilized pH and oxidation-reduction potential can be manufactured.

[0014] According to the apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention, the gas dissolution device adds a pH adjuster, which is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, to pure water, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted to a range of 9 to 14.

[0015] According to the pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention, the gas dissolving device dissolves an inert gas together with a gaseous pH adjuster into pure water, thereby stabilizing the pH and oxidation-reduction potential of the pH / oxidation-reduction potential adjusted water.

[0016] The apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention can produce pH / oxidation-reduction potential adjusted water with a low concentration of dissolved gases and an adjusted pH of 9 to 14. Such pH / oxidation-reduction potential adjusted water can suppress dissolution of various metals that make up the binder of dicing blades. Therefore, the present invention can provide an apparatus for producing pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing, which can reduce the frequency of dicing blade replacement.

[0017] The pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention removes dissolved gases from pure water using a degassing membrane device and adjusts the pH of the pure water using a pH adjustment device that adds at least one pH adjuster selected from gases and liquids.Since the pH adjustment is performed on pure water that has been degassed in advance, the pH of the pure water does not fluctuate, and pH / oxidation-reduction potential adjusted water with stabilized pH and oxidation-reduction potential can be manufactured.

[0018] According to the pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention, the pH adjustment device adds a pH adjuster, which is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, to pure water, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted to a range of 9 to 14.

[0019] According to the apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention, the pH adjustment device adds a pH adjuster containing at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas to pure water, thereby adjusting the pH of the pH / oxidation-reduction potential adjusted water to a range of 9 to 14 and stabilizing the pH and oxidation-reduction potential.

[0020] The pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, and a dissolved oxygen concentration of 50 ppb or less at 25°C.This pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of dicing blades, and therefore can be used as cooling water for blade dicing, thereby reducing the frequency of dicing blade replacement.

[0021] The pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, and a hydrogen peroxide concentration of 30 ppb or less.This pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of dicing blades, and therefore can be used as cooling water for blade dicing, thereby reducing the frequency of dicing blade replacement.

[0022] The pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, a dissolved oxygen concentration of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less at 25°C.This pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of dicing blades, and therefore can be used as cooling water for blade dicing, thereby reducing the frequency of dicing blade replacement.

[0023] According to the pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention, a hydrogen peroxide removal mechanism that removes hydrogen peroxide dissolved as an impurity from pure water is provided upstream of the degassing membrane device, making it possible to reduce the hydrogen peroxide concentration in the pure water and stably maintain the oxidation-reduction potential of the pH / oxidation-reduction potential adjusted water in the range of -0.40 V or more and less than +0.40 V (vs Ag / AgCl).

[0024] According to the pH / oxidation-reduction potential adjusted water manufacturing device of the present invention, a supply flow path is provided for supplying the manufactured pH / oxidation-reduction potential adjusted water as cooling water for a dicing blade in which diamond abrasive grains are fixed by a binder, thereby preventing dissolution of the binder in the dicing blade and reducing the frequency of replacement of the dicing blade.

[0025] According to the pH / oxidation-reduction potential adjusted water manufacturing device of the present invention, a supply flow path is provided for supplying the manufactured pH / oxidation-reduction potential adjusted water as cooling water in the dicing process of the semiconductor manufacturing process, thereby making it possible to reduce the frequency of dicing blade replacement.

[0026] The method for producing pH / oxidation-reduction potential adjusted water of the present invention involves adjusting the pH of pure water by adding a liquid pH adjuster to pure water in a pH adjustment process, removing dissolved gases in the pure water in a degassing process, and dissolving an inert gas in the pure water in a gas dissolution process.By using a liquid pH adjuster, the pH of the pH-adjusted pure water does not fluctuate even when it is degassed, so that pH / oxidation-reduction potential adjusted water can be produced whose pH and oxidation-reduction potential are adjusted to the desired range.

[0027] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, in the pH adjustment step, an aqueous solution of at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine is added to pure water as a pH adjuster, thereby making it possible to adjust the pH of the pH / oxidation-reduction potential adjusted water to a range of 9 to 14.

[0028] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, dissolved gases in pure water are removed in the degassing process, and then a gaseous pH adjuster is added to the pure water in the gas dissolution process.Since the pH is adjusted for pure water that has already been degassed, fluctuations in the pH of the pure water can be prevented.

[0029] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, the pH adjuster is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted to a range of 9 to 14.

[0030] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, the pH adjuster contains an inert gas, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted to a range of 9 to 14, and the pH and oxidation-reduction potential of the pH / oxidation-reduction potential adjusted water can be stabilized.

[0031] According to the apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention, dissolved gases in pure water are removed in the degassing process, and the pH of the pure water is adjusted by adding a liquid pH adjuster to the pure water in the pH adjustment process, thereby making it possible to produce pH / oxidation-reduction potential adjusted water whose pH and oxidation-reduction potential are adjusted to the desired range.

[0032] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, in the pH adjustment step, an aqueous solution of at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine is added to pure water as a pH adjuster, thereby making it possible to adjust the pH of the pH / oxidation-reduction potential adjusted water to a range of 9 to 14.

[0033] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, in the pH adjustment step, a pH adjuster containing at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas is added to pure water, thereby adjusting the pH of the pH / oxidation-reduction potential adjusted water to a range of 9 to 14 and stabilizing the pH and oxidation-reduction potential.

[0034] The method for producing pH / oxidation-reduction potential adjusted water of the present invention produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, and a dissolved oxygen concentration of 50 ppb or less at 25°C.This pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of dicing blades, and therefore can be used to produce pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing, which can reduce the frequency of dicing blade replacement.

[0035] The method for producing pH / oxidation-reduction potential adjusted water of the present invention produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, and a hydrogen peroxide concentration of 30 ppb or less.This pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of dicing blades, and therefore can be used to produce pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing, which can reduce the frequency of dicing blade replacement.

[0036] The method for producing pH / oxidation-reduction potential adjusted water of the present invention produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C, a dissolved oxygen concentration of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less at 25°C.This pH / oxidation-reduction potential adjusted water can be used to suppress the dissolution of various metals that make up the binder of dicing blades, thereby reducing the frequency of dicing blade replacement, and can be used to produce pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing.

[0037] According to the method for producing pH / oxidation-reduction potential adjusted water of the present invention, a hydrogen peroxide removal process is carried out before the degassing process in which hydrogen peroxide dissolved as an impurity is removed from the pure water. This makes it possible to reduce the hydrogen peroxide concentration in the pure water, and to stably maintain the oxidation-reduction potential of the pH / oxidation-reduction potential adjusted water in the range of -0.40 V or more and less than +0.40 V (vs Ag / AgCl).

[0038] According to the semiconductor device manufacturing method of the present invention, the produced pH / oxidation-reduction potential adjusted water is used as cooling water for a dicing blade in which diamond abrasive grains are fixed by a binder, thereby preventing the binder in the dicing blade from dissolving and reducing the frequency of dicing blade replacement.

[0039] According to the semiconductor device manufacturing method of the present invention, the produced pH / oxidation-reduction potential adjusted water is used as cooling water in the dicing step of the semiconductor manufacturing process, thereby making it possible to reduce the frequency of replacing dicing blades. [Brief explanation of the drawings]

[0040] [Figure 1] 1 is a schematic diagram showing an apparatus for producing pH / oxidation-reduction potential adjusted water according to a first embodiment of the present invention. [Figure 2] FIG. 3 is a schematic diagram showing an apparatus for producing pH / oxidation-reduction potential adjusted water according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a schematic diagram showing an apparatus for producing pH / oxidation-reduction potential adjusted water according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0041] The apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention comprises at least a degassing membrane device having a degassing membrane that removes gases dissolved as impurities from pure water, and a pH adjustment device that adjusts the pH of pure water. The apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention may further comprise a gas-dissolving membrane device having a gas-dissolving membrane that dissolves an inert gas in pure water. The pH adjustment device may also supply a gaseous pH adjuster to the gas-dissolving membrane device. The apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention is capable of producing pH / oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) at 25°C. Hereinafter, a manufacturing apparatus and a manufacturing method of pH·redox potential adjusted water, which are embodiments of the present invention, will be described in detail with reference to the drawings.

[0042] 〔First Embodiment〕 <Manufacturing Apparatus of pH·Redox Potential Adjusted Water> FIG. 1 shows a pH·redox potential adjusted water manufacturing apparatus according to the first embodiment of the present invention. The pH·redox potential adjusted water manufacturing apparatus 1 shown in FIG. 1 includes a platinum group metal supported resin column 3 as a hydrogen peroxide removing mechanism, a pH adjuster injection line 4 (pH adjusting device), a degassing membrane device 5 for degassing dissolved gas in pure water, a gas dissolving device 6 for dissolving inert gas in pure water, and a storage tank 7 for storing the adjusted pH·redox potential adjusted water (hereinafter sometimes referred to as adjusted water).

[0043] The platinum group metal supported resin column 3 as a hydrogen peroxide removing mechanism is provided to make the hydrogen peroxide concentration of pure water W, which is raw water, 30 ppb or less. However, the hydrogen peroxide removing mechanism is not necessarily essential in this embodiment. If the hydrogen peroxide concentration of pure water W is 30 ppb or less, the hydrogen peroxide removing mechanism may not be provided.

[0044] In this embodiment, examples of the platinum group metal supported on the platinum group metal supported resin used for the platinum group metal supported resin column 3 include ruthenium, rhodium, palladium, osmium, iridium, and platinum. These platinum group metals can be used alone, in combination of two or more, as an alloy of two or more, or as a purified product of a naturally produced mixture without being separated into a single body. Among these, platinum, palladium, platinum / palladium alloy alone or a mixture of two or more of these can be preferably used because of their strong catalytic activity. Also, nanoparticles of these metals can be particularly preferably used.

[0045] In the platinum group metal-supported resin column 3, an ion exchange resin can be used as the carrier resin for supporting the platinum group metal. Among these, an anion exchange resin is particularly suitable. Since platinum-based metals are negatively charged, they are stably supported on the anion exchange resin and are not easily peeled off. The exchange group of the anion exchange resin is preferably in the OH form. The OH form anion exchange resin makes the resin surface alkaline, accelerating the decomposition of hydrogen peroxide.

[0046] The pH adjuster injection line 4 (pH adjuster) is not particularly limited, and a general chemical injection device can be used. For example, the pH adjuster injection line 4 shown in Fig. 1 merges with the supply line 2 and adds a liquid pH adjuster to pure water. The pH adjuster injection line 4 is equipped with a pH adjuster tank 4A and a liquid supply mechanism 4B that communicates with the pH adjuster tank 4A.

[0047] The pH adjuster tank 4A is capable of storing a liquid pH adjuster. The pH adjuster tank 4A may have an inert gas supply mechanism. It is desirable to provide a mechanism for purging the pH adjuster tank 4A with an inert gas or for removing dissolved oxygen from the pH adjuster in the tank using a degassing membrane.

[0048] The liquid supply mechanism 4B can be a pump such as a diaphragm pump to supply the liquid pH adjuster. Alternatively, a pressure pump can be suitably used in which the pH adjuster is placed in a sealed container such as the pH adjuster tank 4A together with an inert gas such as N2 gas, and the pH adjuster is pushed out by the pressure of the inert gas.

[0049] The degassing membrane device 5 is disposed downstream of the pH adjuster injection line 4. The degassing membrane device 5 is a membrane-type degassing membrane device having a degassing membrane. A vacuum pump (VP) 5A is connected to the gas phase side of the degassing membrane of the degassing membrane device 5. The degassing membrane device 5 is configured such that pure water flows through one side (liquid phase side) of the degassing membrane and the other side (gas phase side) is suctioned by the vacuum pump (VP) 5A, thereby allowing dissolved gases such as dissolved oxygen to pass through the degassing membrane and migrate to the gas phase chamber side for removal. The degassing membrane may be any membrane that allows gases such as oxygen, nitrogen, and steam to pass through but does not allow water to pass through, such as silicone rubber, polytetrafluoroethylene, polyolefin, or polyurethane. Various commercially available degassing membranes can be used.

[0050] The gas dissolving device 6 is disposed downstream of the degassing membrane device 5. The gas dissolving device 6 is equipped with a gas dissolving membrane, and the gas phase chamber side of the gas dissolving membrane is connected to a source of N2 gas as an inert gas. The gas dissolving membrane device 6 flows the adjusted water W1 into one side (liquid phase side) of the gas dissolving membrane and supplies N2 gas to the other side (gas phase side), thereby dissolving the inert gas into the adjusted water W1. Note that the inert gas is not limited to N2 gas, and argon, helium, etc. can also be suitably used.

[0051] The storage tank 7 is disposed downstream of the gas dissolver 6. The storage tank 7 is capable of storing the adjusted water W1. In this embodiment, the storage tank 7 is purged with an inert gas.

[0052] The supply line 2 then passes through the storage tank 7 and reaches the point of use UP. An example of the point of use UP to which the supply line 2 reaches is a dicing device for dicing semiconductor substrates. An example of a dicing device is a dicing device that cuts semiconductor substrates with a dicing blade. An example of a dicing blade is one in which diamond abrasive grains are fixed to the outer peripheral end surface of a disc-shaped blade with a binder. Examples of binders for diamond abrasive grains include those made of metals such as nickel, cobalt, copper, tin, silver, and tungsten.

[0053] Further, in the present embodiment, on the downstream side of the gas dissolving device 6 in the supply line 2, for example, in the storage tank 7, a pH meter as pH measuring means (not shown) and an adjustment water quality monitoring mechanism such as an ORP meter as oxidation-reduction potential measuring means are provided respectively. Further, these pH meters and ORP meters are connected to a control device such as a personal computer. And this control device can control the injection amount of the pH adjuster and the platinum group metal-supported resin column 3 based on the measured values of these pH meters and ORP meters.

[0054] <Pure water> In the present embodiment, the pure water W serving as raw water is, for example, ultrapure water having a resistivity of 18.1 MΩ·cm or more, fine particles of 1000 pieces / L or less with a particle size of 50 nm or more, viable bacteria of 1 piece / L or less, TOC (Total Organic Carbon) of 1 μg / L or less, total silicon of 0.1 μg / L or less, metals of 1 ng / L or less, ions of 10 ng / L or less, hydrogen peroxide of 30 μg / L or less, and a water temperature of 25 ± 2°C. However, in the present embodiment, the pure water W as raw water may contain hydrogen peroxide exceeding 30 ppb, dissolved oxygen of 50 ppb or more, and further may have a pH of less than 9.

[0055] <pH adjuster> In the present embodiment, there is no particular limitation on the pH adjuster injected from the pH adjuster tank 4A. In order to adjust the pH of the adjustment water to 9 to 14, at least one aqueous solution selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine can be used. When the adjustment water is used as the cooling water in the dicing process, it is preferably made alkaline to prevent the dissolution of the metal of the binder, but an alkali metal solution such as sodium hydroxide may not be suitable because it contains a metal component. Therefore, in the present embodiment, it is most preferable to use ammonia, tetrahydroammonium, choline, methylamine, dimethylamine, trimethylamine, etc.

[0056] <Method for Producing pH and Redox Potential Adjusted Water> A method for producing pH and redox potential adjusted water using the production apparatus 1 of pH and redox potential adjusted water of the present embodiment having the configuration as described above will be described below.

[0057] In the present embodiment, a hydrogen peroxide removal step, a pH adjustment step, a degassing step, a gas dissolution step, and a supply step are performed.

[0058] The hydrogen peroxide removal step is a step of removing hydrogen peroxide dissolved in pure water W to make the hydrogen peroxide concentration 30 ppb or less. However, the hydrogen peroxide removal step is not necessarily essential in the present embodiment. If the hydrogen peroxide concentration of pure water W is 30 ppb or less, the hydrogen peroxide removal step may not be performed. Pure water with the hydrogen peroxide concentration limited to 30 ppb or less has a redox potential in the range of -0.40 V or more and less than +0.40 V (vs Ag / AgCl). Also, in the pH adjustment step, the pH of the pure water after the hydrogen peroxide removal step is adjusted to the range of 9 to 14. Also, in the degassing step, the dissolved gas contained in the pure water is removed to make the dissolved oxygen concentration 50 ppb or less. Furthermore, in the gas dissolution step, an inert gas is dissolved in the pure water to stabilize the pH and redox potential of the adjusted water. In the supply step, the adjusted water W1 is supplied to the semiconductor manufacturing process through the supply line 2. Details of each step will be described below.

[0059] Since pure water W as raw water generally contains hydrogen peroxide at the level of several tens of ppb, it is necessary to remove the hydrogen peroxide in pure water W in advance in order to accurately control the redox potential of the adjusted water. Therefore, as the hydrogen peroxide removal step, pure water W is supplied from the supply line 2 to the platinum group metal supported resin column 3. In this platinum group metal supported resin column 3, the hydrogen peroxide in pure water W is decomposed and removed by the catalytic action of the platinum group metal, that is, it functions as a hydrogen peroxide removal mechanism.

[0060] Next, in the pH adjustment step, a liquid pH adjuster is injected from the pH adjuster tank 4A into the pure water W. The amount of pH adjuster added can be set appropriately depending on the desired pH, the flow rate in the supply line 2, and the concentration of the pH adjuster. For example, if the adjusted water used as cooling water in the dicing step is to be alkaline, an amount of pH adjuster that brings the pH of the pure water into the range of 9 to 14 should be added.

[0061] Next, in the degassing process, the pH-adjusted adjusted water W1 is degassed in a degassing membrane device 5. In the degassing membrane device 5, the adjusted water W1 is passed through the liquid-phase compartment of a liquid-phase compartment and a gas-phase compartment formed by a hydrophobic gas-permeable membrane, and the gas-phase compartment is depressurized using a vacuum pump (VP) 5A. This removes dissolved gases, such as dissolved oxygen, contained in the adjusted water W1 by transferring them to the gas-phase compartment through the hydrophobic gas-permeable membrane. This reduces the dissolved oxygen concentration in the adjusted water W1 to an extremely low level. Furthermore, because liquid pH adjusters are not degassed, degassing them after preparing the adjusted water W1 reduces the risk of chemical leakage during vacuum degassing of these agents.

[0062] Next, in the gas dissolution step, an inert gas is supplied to the adjusted water W1 after the degassing step using a gas dissolution membrane device 6 to stabilize the properties of the adjusted water W1, thereby producing stabilized adjusted water W1. The inert gas is preferably dissolved up to a saturated amount.

[0063] Once adjusted water W1 is produced in this manner, it is stored in the storage tank 7. Since the storage tank 7 is purged with an inert gas, it is possible to prevent oxygen or carbon dioxide from dissolving in the adjusted water W1 while the adjusted water W1 is being stored, which would cause fluctuations in pH and oxidation-reduction potential. At this time, the control device controls the amount of pH adjuster added from the pH adjuster tank 4A and the platinum group metal-supported resin column 3 based on the measurement results of a pH meter and an ORP meter (not shown), thereby enabling a stable supply of adjusted water W1 adjusted to the desired pH and oxidation-reduction potential.

[0064] The water quality of the produced adjusted water W1 is such that the pH is 9 to 14 and the oxidation-reduction potential at 25° C. is −0.40 V or more and less than +0.40 V (vs Ag / AgCl). The produced adjusted water W1 may have a dissolved oxygen concentration at 25°C of 50 ppb or less. The produced adjusted water W1 may have a hydrogen peroxide concentration of 30 ppb or less. Furthermore, the produced adjusted water W1 may have a pH of 9 to 14, an oxidation-reduction potential at 25°C of -0.40 V or more and less than +0.40 V (vs Ag / AgCl), a dissolved oxygen concentration at 25°C of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less.

[0065] The adjusted water W1 thus produced is then sent to the point of use UP via the supply line 2 in the supply step.

[0066] (Example of supplying pH / oxidation-reduction potential adjusted water) Hereinafter, a case where the adjusted water W1 produced as described above is used as cooling water in the dicing process will be described.

[0067] In this embodiment, the adjusted water W1 is supplied to the semiconductor manufacturing process via a supply line 2. An example of the semiconductor manufacturing process is a dicing machine that uses a dicing blade to cut a semiconductor substrate. The dicing blade is a disk-shaped blade with diamond abrasive grains fixed to the outer peripheral end surface with a binder. The binder for the diamond abrasive grains is made of any metal, such as nickel, cobalt, copper, tin, silver, or tungsten.

[0068] When cutting a semiconductor substrate with a dicing blade, conditioning water is supplied as cooling water. The quality of the conditioning water is such that the pH is 9 to 14, and the oxidation-reduction potential at 25°C is -0.40 V or more and less than +0.40 V (vs Ag / AgCl). Further, the quality of the conditioning water satisfies either or both of the conditions that the dissolved oxygen concentration at 25°C is 50 ppb or less and the hydrogen peroxide concentration is 30 ppb or less. Such conditioning water is alkaline and has an oxidation-reduction potential in the range of ±0.40 V, so it does not dissolve the metal constituting the binder of the dicing blade. Therefore, deterioration of the dicing blade can be prevented, and the frequency of replacing the dicing blade can be reduced.

[0069] 〔Second Embodiment〕 <pH·Oxidation-Reduction Potential Conditioning Water Production Apparatus> FIG. 2 shows a pH·oxidation-reduction potential conditioning water production apparatus 11 according to the second embodiment of the present invention. In FIG. 2, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

[0070] The pH·oxidation-reduction potential conditioning water production apparatus 11 shown in FIG. 2 is provided with a degassing membrane device 5 for degassing the dissolved gas in pure water and a gas dissolution device 16 for dissolving gas in pure water in the supply line 2 of pure water W. Further, the pH·oxidation-reduction potential conditioning water production apparatus 11 shown in FIG. 2 is provided with a pH adjuster injection line 14 (pH adjustment device) for supplying a pH adjuster to the gas dissolution device 16.

[0071] Note that the pH·oxidation-reduction potential conditioning water production apparatus 11 shown in FIG. 2 may be provided with a platinum group metal-supported resin column as a hydrogen peroxide removal mechanism in the front stage of the degassing membrane device 5. Further, a storage tank for storing the adjusted pH·oxidation-reduction potential conditioning water (conditioning water) may be provided in the subsequent stage of the gas dissolution device 16.

[0072] The platinum group metal-supported resin column, which serves as a hydrogen peroxide removal mechanism, is provided to reduce the hydrogen peroxide concentration in the raw pure water W to 30 ppb or less. However, the hydrogen peroxide removal mechanism is not necessarily required in this embodiment, and if the hydrogen peroxide concentration in the pure water W is 30 ppb or less, the hydrogen peroxide removal mechanism does not need to be provided. The details of the platinum group metal-supported resin column are the same as those in the first embodiment.

[0073] The degassing membrane device 5 is a membrane-type degassing membrane device and has a degassing membrane. A vacuum pump (VP) 5A is connected to the gas phase side of the degassing membrane of the degassing membrane device 5. The detailed configuration is the same as in the first embodiment.

[0074] The gas dissolver 16 is disposed downstream of the degassing membrane device 5. The gas dissolver 16 is equipped with a gas dissolution membrane, and the gas phase chamber side of the gas dissolution membrane is connected to a pH adjuster injection line 14 (pH adjuster). The gas dissolution membrane device 16 flows pure water W into one side (liquid phase side) of the gas dissolution membrane and supplies a gaseous pH adjuster to the other side (gas phase side), thereby dissolving the pH adjuster in the pure water W and adjusting the pH of the pure water W1 to 9 to 14. The gas dissolver 16 may also dissolve an inert gas into the pure water W along with the pH adjuster. Suitable inert gases include N2 gas, argon, and helium. The inert gas is preferably dissolved to a saturated amount.

[0075] The pH adjuster injection line 14 (pH adjuster) is not particularly limited, and may be any pipe capable of supplying a gaseous pH adjuster. The pH adjuster injection line 14 shown in FIG. 2 is connected to the gas phase chamber side of the gas dissolution membrane of the gas dissolution membrane, and supplies a gaseous pH adjuster to the gas phase chamber side of the gas dissolution membrane. The pH adjuster injection line 14 can also supply an inert gas to the gas dissolution device 16 along with the gaseous pH adjuster. That is, the pH adjuster injection line 14 can supply a mixed gas of a pH adjuster and an inert gas to the gas dissolution device 16. A pH adjuster tank filled with a pH adjuster, an inert gas source, a gas pressure mechanism for pressurizing and supplying the pH adjuster and inert gas, and the like may be provided upstream of the pH adjuster injection line 14.

[0076] The storage tank is disposed downstream of the gas dissolver 16, as required. The storage tank is capable of storing the adjusted water W1. In this embodiment, the storage tank is purged with an inert gas.

[0077] The supply line 2 then passes through the gas dissolving device 16 or the storage tank and reaches the point of use UP. An example of the point of use UP to which the supply line 2 reaches is a dicing device that uses a dicing blade to cut a semiconductor substrate. An example of a dicing blade is a disc-shaped blade with diamond abrasive grains fixed to the outer peripheral end surface with a binder. Examples of binders for diamond abrasive grains include those made of metals such as nickel, cobalt, copper, tin, silver, and tungsten.

[0078] In this embodiment, downstream of the gas dissolver 6 on the supply line 2, for example in the storage tank, are provided with an adjusted water quality monitoring mechanism, such as a pH meter serving as a pH measurement means and an ORP meter serving as an oxidation-reduction potential measurement means, both of which are not shown. These pH meter and ORP meter are connected to a control device such as a personal computer. This control device can control the amount of pH adjuster injected and the platinum group metal-supported resin column based on the measurements of the pH meter and ORP meter.

[0079] <Pure water> In this embodiment, the pure water W serving as raw water is the same as in the case of the first embodiment.

[0080] <pH adjuster> In this embodiment, as the pH adjuster injected from the pH adjuster injection line 14, there is no particular limitation as long as it is a gas. In order to adjust the pH of pure water to 9 to 14, at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine can be used. Further, an inert gas such as nitrogen, argon, or helium can be mixed into the pH adjuster. These pH adjusters are all supplied in a gaseous state.

[0081] <Method for producing pH-adjusted and redox potential-adjusted water> A method for producing pH-adjusted and redox potential-adjusted water using the production apparatus 11 for pH-adjusted and redox potential-adjusted water of this embodiment having the configuration described above will be described below.

[0082] In this embodiment, a degassing step, a gas dissolution step for dissolving a pH adjuster, and a supply step are performed. Further, a hydrogen peroxide removal step may be performed before the degassing step.

[0083] The hydrogen peroxide removal step is a step of removing hydrogen peroxide dissolved in the pure water W to make the hydrogen peroxide concentration 30 ppb or less. However, the hydrogen peroxide removal step is not necessarily essential in this embodiment. If the hydrogen peroxide concentration of the pure water W is 30 ppb or less, the hydrogen peroxide removal step may not be performed. The pure water with the hydrogen peroxide concentration limited to 30 ppb or less has a redox potential in the range of -0.40 V or more and less than +0.40 V (vs Ag / AgCl). Also, the degassing step removes the dissolved gas contained in the pure water to make the dissolved oxygen concentration 50 ppb or less. Furthermore, the gas dissolution step adjusts the pH of the pure water by dissolving a pH adjuster in the pure water. Also, by supplying an inert gas, the pH and the redox potential of the pH-adjusted adjusted water are stabilized. In the supply step, the adjusted water W1 is supplied to the semiconductor manufacturing process through a supply line 2. Each step will be described in detail below.

[0084] Pure water W as raw water generally contains hydrogen peroxide at the level of several tens of ppb, and therefore, in order to accurately control the oxidation-reduction potential of the adjusted water, it is necessary to remove the hydrogen peroxide from the pure water W beforehand. Therefore, as a hydrogen peroxide removal step, the pure water W is supplied from a supply line 2 to a platinum group metal-supported resin column 3. In this platinum group metal-supported resin column 3, the catalytic action of the platinum group metal decomposes and removes the hydrogen peroxide in the pure water W, i.e., it functions as a hydrogen peroxide removal mechanism.

[0085] Next, in the degassing step, the pure water W1 is degassed in a degassing membrane device 5. In the degassing membrane device 5, the pure water W is passed through the liquid-phase chamber side of a liquid-phase chamber and a gas-phase chamber formed with a hydrophobic gas-permeable membrane, and the gas-phase chamber is depressurized with a vacuum pump (VP) 5A, thereby removing dissolved gases such as dissolved oxygen contained in the pure water W by transferring them to the gas-phase chamber through the hydrophobic gas-permeable membrane. This allows the dissolved oxygen concentration in the pure water W to be reduced to a very low level, for example, to 50 ppb or less.

[0086] In this embodiment, the degassing step must be performed before the gas dissolving step in order to adjust the pH of the adjusted water to a range of 9 to 14. If the degassing step is performed after the gas dissolving step, the pH adjuster added to the pure water in the gas dissolving step may be degassed, causing the pH of the adjusted water to deviate from the range of 9 to 14.

[0087] Next, as the gas dissolution step, a gaseous pH adjuster is supplied from the pH adjuster injection line 14 to the gas dissolution membrane, and the gaseous pH adjuster is dissolved in pure water through the gas dissolution membrane to adjust the pH of the pure water. The addition of the pH adjuster may be appropriately set according to the desired pH, the flow rate of the supply line 2, and the concentration of the pH adjuster. For example, when the conditioning water as the cooling water in the dicing process is made alkaline, an amount that makes the pH of the pure water fall within the range of 9 to 14 may be added. Also, an inert gas may be dissolved in the pure water W together with the pH adjuster. By dissolving the inert gas, it is possible to prevent the mixing of oxygen and carbon dioxide and stabilize the pH and the redox potential. The inert gas may be dissolved to the saturation amount.

[0088] After producing the conditioning water W1 in this way, it may be stored in the storage tank 7. Since the storage tank 7 is purged with an inert gas, it is possible to prevent oxygen and carbon dioxide from dissolving in the obtained conditioning water W1 and the pH and the redox potential from fluctuating while the conditioning water W1 is being stored. At this time, based on the measurement results of a pH meter and an ORP meter (not shown), by controlling the addition amount of the pH adjuster from the pH adjuster injection line 14 and controlling the platinum group metal-supported resin column with a control device, it is possible to stably supply the conditioning water W1 adjusted to the desired pH and redox potential.

[0089] The quality of the produced conditioning water W1 is the same as in the case of the first embodiment.

[0090] Then, the conditioning water W1 produced in this way is sent as a supply step through the supply line 2 to the use point UP and used as the cooling water in the dicing process.

[0091] 〔Third Embodiment〕 <Apparatus for Producing pH and Redox Potential Adjusted Water> Figure 3 shows a pH / oxidation-reduction potential adjusted water producing apparatus 21 according to a third embodiment of the present invention. In Figure 3, the same components as those in the first embodiment described above are given the same reference numerals, and detailed description thereof will be omitted. The pH / oxidation-reduction potential adjusted water producing apparatus 21 shown in Figure 3 is provided with a degassing membrane device 5 for degassing dissolved gases in the pure water, and a pH adjuster injection line 24 as a pH adjuster for adjusting the pH of the pure water, in a supply line 2 for pure water W.

[0092] 3 may be provided with a platinum group metal-supported resin column as a hydrogen peroxide removal mechanism upstream of the degassing membrane device 5. Furthermore, a storage tank for storing the adjusted pH / oxidation-reduction potential adjusted water (adjusted water) may be provided downstream of the pH adjuster 24.

[0093] The platinum group metal-supported resin column, which serves as a hydrogen peroxide removal mechanism, is provided to reduce the hydrogen peroxide concentration in the raw pure water W to 30 ppb or less. However, the hydrogen peroxide removal mechanism is not necessarily required in this embodiment, and if the hydrogen peroxide concentration in the pure water W is 30 ppb or less, the hydrogen peroxide removal mechanism does not need to be provided. The details of the platinum group metal-supported resin column are the same as those in the first embodiment.

[0094] The degassing membrane device 5 is a membrane-type degassing membrane device and has a degassing membrane. A vacuum pump (VP) 5A is connected to the gas phase side of the degassing membrane of the degassing membrane device 5. The detailed configuration is the same as in the first embodiment.

[0095] The pH adjuster injection line 24 as a pH adjuster is not particularly limited as long as it can add at least one pH adjuster selected from gas and liquid to pure water. The pH adjuster injection line 24 is equipped with a pH adjuster tank 24A and a supply mechanism 24B connected to the pH adjuster tank 24A. The pH adjuster tank 24A may also have a supply mechanism for an inert gas such as nitrogen.

[0096] When the pH adjuster is a liquid, a pump such as a diaphragm pump can be used as the supply mechanism 24B. In this case, it is desirable to purge the pH adjuster tank 24A with an inert gas or to provide a mechanism for removing dissolved oxygen from the pH adjuster liquid in the tank using a degassing membrane. Alternatively, a pressure pump can be used in which the pH adjuster is placed in the pH adjuster tank 24A together with an inert gas such as N2 gas, and the pressure of the inert gas is used to push out the pH adjuster.

[0097] Furthermore, when the pH adjuster is a gas, the supply mechanism 24B can be a direct gas-liquid contact device such as a gas permeable membrane module or an ejector.

[0098] The storage tank is disposed downstream of the pH adjuster injection line 24, as required. The storage tank is capable of storing the adjusted water W1. In this embodiment, the storage tank is purged with an inert gas.

[0099] The supply line 2, which passes through the pH adjuster injection line 24 or the storage tank, reaches the point of use UP. An example of the point of use UP to which the supply line 2 reaches is a dicing device that uses a dicing blade to cut a semiconductor substrate. An example of a dicing blade is a disc-shaped blade with diamond abrasive grains fixed to the outer peripheral end surface with a binder. Examples of binders for diamond abrasive grains include those made of metals such as nickel, cobalt, copper, tin, silver, and tungsten.

[0100] In this embodiment, downstream of the pH adjuster injection line 24 of the supply line 2, for example in the storage tank, are provided an adjusted water quality monitoring mechanism, such as a pH meter serving as a pH measurement means and an ORP meter serving as an oxidation-reduction potential measurement means, both of which are not shown. These pH meter and ORP meter are connected to a control device such as a personal computer. Based on the measured values ​​of the pH meter and ORP meter, this control device can control the amount of pH adjuster injected and the platinum group metal-supported resin column.

[0101] <Pure water> In this embodiment, the pure water W serving as raw water can be the same as that in the first embodiment.

[0102] <pH adjuster> In this embodiment, there is no particular limitation on the pH adjuster injected from the pH adjuster injection line 24, and it may be at least one pH adjuster selected from gases and liquids. Specifically, as the liquid pH adjuster for adjusting the pH of pure water to 9 - 14, an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine can be used. Further, as the gaseous pH adjuster, one containing at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine and an inert gas can be used.

[0103] <Method for producing pH·oxidation-reduction potential adjusted water> A method for producing pH·oxidation-reduction potential adjusted water using the production apparatus 21 for pH·oxidation-reduction potential adjusted water of this embodiment having the configuration as described above will be described below.

[0104] In this embodiment, a degassing step for degassing pure water, a pH adjustment step for adjusting the pH of pure water, and a supply step are performed. Further, a hydrogen peroxide removal step may be performed before the degassing step.

[0105] The hydrogen peroxide removal step is a step of removing hydrogen peroxide dissolved in pure water W to make the hydrogen peroxide concentration 30 ppb or less. However, the hydrogen peroxide removal step is not necessarily essential in this embodiment. If the hydrogen peroxide concentration of pure water W is 30 ppb or less, the hydrogen peroxide removal step may not be performed. Pure water with the hydrogen peroxide concentration limited to 30 ppb or less has an oxidation-reduction potential in the range of -0.40 V or more and less than +0.40 V (vs Ag / AgCl). The degassing step removes the dissolved gas contained in pure water to make the dissolved oxygen concentration 50 ppb or less. In the pH adjustment step, the pH of the pure water is adjusted by adding at least one pH adjuster selected from gases and liquids, and the pH and redox potential of the pH-adjusted water are stabilized by supplying an inert gas. In the supply step, the adjusted water W1 is supplied to the semiconductor manufacturing process through a supply line 2. Each step will be described in detail below.

[0106] Pure water W as raw water generally contains hydrogen peroxide at the level of several tens of ppb, and therefore, in order to accurately control the oxidation-reduction potential of the adjusted water, it is necessary to remove the hydrogen peroxide from the pure water W beforehand. Therefore, as a hydrogen peroxide removal step, the pure water W is supplied from a supply line 2 to a platinum group metal-supported resin column 3. In this platinum group metal-supported resin column 3, the catalytic action of the platinum group metal decomposes and removes the hydrogen peroxide in the pure water W, i.e., it functions as a hydrogen peroxide removal mechanism.

[0107] Next, in the degassing step, the pure water W1 is degassed in a degassing membrane device 5. In the degassing membrane device 5, the pure water W is passed through the liquid-phase chamber side of a liquid-phase chamber and a gas-phase chamber formed with a hydrophobic gas-permeable membrane, and the gas-phase chamber is depressurized with a vacuum pump (VP) 5A, thereby removing dissolved gases such as dissolved oxygen contained in the pure water W by transferring them to the gas-phase chamber through the hydrophobic gas-permeable membrane. This allows the dissolved oxygen concentration in the pure water W to be reduced to a very low level, for example, to 50 ppb or less.

[0108] Next, in the pH adjustment step, at least one pH adjuster selected from a gas and a liquid is injected from the pH adjuster tank 24A into the pure water W. The amount of pH adjuster added can be set appropriately depending on the desired pH, the flow rate of the supply line 2, and the concentration of the pH adjuster. For example, if the adjusted water used as cooling water in the dicing step is to be alkaline, an amount of pH adjuster added will be enough to bring the pH of the pure water to a range of 9 to 14. Furthermore, when adjusting the pH with a gaseous pH adjuster, adding an inert gas to the pure water together with the pH adjuster can prevent the incorporation of oxygen or carbon dioxide and stabilize the pH and oxidation-reduction potential.

[0109] Once the adjusted water W1 is produced in this manner, it may be stored in a storage tank. Because the storage tank is purged with an inert gas, it is possible to prevent oxygen and carbon dioxide from dissolving in the adjusted water W1 while the adjusted water W1 is being stored, which would cause fluctuations in pH and oxidation-reduction potential. Based on the measurement results of a pH meter and an ORP meter (not shown), the control device controls the amount of pH adjuster added through the pH adjuster injection line 24 and the platinum group metal-supported resin column, thereby enabling a stable supply of adjusted water W1 adjusted to the desired pH and oxidation-reduction potential.

[0110] The quality of the adjusted water W1 produced is the same as in the first embodiment.

[0111] The adjusted water W1 thus produced is sent to the use point UP via the supply line 2 in the supply step, and is used as cooling water in the dicing step.

[0112] As described above, the apparatus and method for producing pH / oxidation-reduction potential adjusted water of this embodiment can produce conditioned water with a low concentration of dissolved gases, an adjusted pH of 9 to 14, and an adjusted oxidation-reduction potential of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl). Such conditioned water can suppress dissolution of various metals that make up the binder of the dicing blade. Therefore, this embodiment can provide an apparatus and method for producing pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing, which can reduce the frequency of dicing blade replacement. [Example]

[0113] The present invention will be described in more detail below with reference to examples.

[0114] [Production of adjusted water of Example 1] Using the pH / oxidation-reduction potential adjusted water manufacturing apparatus shown in Figure 3, the hydrogen peroxide in pure water was reduced to 30 ppb or less using a hydrogen peroxide removal mechanism, and then the amount of dissolved oxygen in the pure water was reduced to 50 ppb or less using a degassing membrane device 5.Ammonia water was then added from pH adjuster tank 24A to produce an ammonia / hydrogen peroxide aqueous solution (ammonia concentration: 1 ppm, pH 9 (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: +0.31 V) as adjusted water W1.

[0115] [Production of adjusted water of Example 2] In the same manner as in Example 1, an aqueous solution of ammonia and hydrogen peroxide (ammonia concentration: 100 ppm, pH 10 (23° C.), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: +0.17 V) was produced as adjusted water W1.

[0116] [Production of adjusted water of Example 3] In the same manner as in Example 1, an aqueous solution of ammonia and hydrogen peroxide (ammonia concentration: 100 ppm, pH 10 (23° C.), hydrogen peroxide concentration: less than 1 ppb, oxidation-reduction potential: +0.15 V) was produced as adjusted water W1.

[0117] [Production of adjusted water of Example 4] Using the pH / oxidation-reduction potential adjusted water manufacturing apparatus shown in Figure 1, the hydrogen peroxide in pure water was reduced to 30 ppb or less using a hydrogen peroxide removal mechanism, and then the dissolved oxygen content in the pure water was reduced to 50 ppb or less using a degassing membrane device 5.Ammonia water was then added from pH adjuster tank 4A, and nitrogen was further dissolved using a gas dissolution membrane device to produce an ammonia / hydrogen peroxide aqueous solution (ammonia concentration: 100 ppm, pH 11 (23°C), hydrogen peroxide concentration: less than 1 ppb, oxidation-reduction potential: +0.15 V) as adjusted water W1.

[0118] [Production of adjusted water of Example 5] Using the pH / oxidation-reduction potential adjusted water manufacturing equipment shown in Figure 3, the hydrogen peroxide in pure water was reduced to 30 ppb or less using a hydrogen peroxide removal mechanism, and then the amount of dissolved oxygen in the pure water was reduced to 50 ppb or less using a degassing membrane device 5.After that, sodium hydroxide aqueous solution was added from pH adjuster tank 24A to produce adjusted water W1, a sodium hydroxide / hydrogen peroxide aqueous solution (sodium hydroxide concentration: 1000 ppm, pH 12 (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: +0.05 V).

[0119] [Production of adjusted water of Example 6] Using the pH / oxidation-reduction potential adjusted water manufacturing equipment shown in Figure 3, the hydrogen peroxide in pure water was reduced to 30 ppb or less using a hydrogen peroxide removal mechanism, and then the amount of dissolved oxygen in the pure water was reduced to 50 ppb or less using a degassing membrane device 5.After that, sodium hydroxide aqueous solution was added from pH adjuster tank 24A to produce adjusted water W1, a sodium hydroxide / hydrogen peroxide aqueous solution (sodium hydroxide concentration: 5%, pH 14 (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: -0.20 V).

[0120] [Production of adjusted water of Comparative Example 1] Using the pH / oxidation-reduction potential adjusted water manufacturing apparatus shown in Figure 3, the hydrogen peroxide in pure water was reduced to 30 ppb or less using a hydrogen peroxide removal mechanism, and then the amount of dissolved oxygen in the pure water was reduced to 50 ppb or less using a degassing membrane device 5, thereby producing ultrapure water (pH 9 or less (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: +0.40 V) as adjusted water W1.

[0121] [Production of adjusted water of Comparative Example 2] Using the pH / oxidation-reduction potential adjusted water manufacturing equipment shown in Figure 3, the hydrogen peroxide in pure water was reduced to 30 ppb or less using a hydrogen peroxide removal mechanism, and then the amount of dissolved oxygen in the pure water was reduced to 50 ppb or less using a degassing membrane device 5.Furthermore, carbon dioxide was added to the pure water through a pH adjustment line 24, thereby producing carbonated water (carbonate concentration: 30 ppm, pH 9 or less (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: +0.41 V) as adjusted water W1.

[0122] (Solubility in Ni film) A rectangular test piece measuring 20 mm × 20 mm was cut from a 300 mm diameter nickel-coated substrate. This test piece was immersed in the adjusted water of Examples 1 to 6 and Comparative Examples 1 and 2 at 23°C for 20 minutes. After immersion, the surface of the nickel film on the test piece was observed with an atomic force microscope (AFM) to confirm the surface roughness (double average surface roughness (Rms)) (the same applies below). The amount of nickel dissolved into the immersion solution was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The nickel dissolution rate was calculated from the amount of nickel dissolved by immersion, and the reliability of the dicing blade was evaluated based on this dissolution rate. Furthermore, the charging potential of the test piece after immersion was measured using a surface electrometer. The results are shown in Table 1.

[0123] The evaluation criteria for the surface roughness of the nickel film were as follows:

[0124] [Surface roughness] Good: The double average surface roughness (Rms) of the nickel film is less than 1 nm. Good: The double average surface roughness (Rms) of the nickel film is 1 nm or more and less than 3 nm. Poor: The double average surface roughness (Rms) of the nickel film is 3 nm or more.

[0125] The reliability of the dicing blade was evaluated by estimating the amount of blade wear when dicing was performed using the adjusted water of Examples 1 to 6 and Comparative Examples 1 and 2, based on the dissolution rate of the nickel film, and the smaller the amount of wear, the better the reliability was evaluated. The dicing blade and dicing conditions used were as follows. There is a correlation between the dissolution rate of the nickel film and the amount of blade wear when dicing was performed under the following conditions, and the reliability of the blade was evaluated based on the estimated amount of blade wear according to the following criteria. Blades evaluated as "good" or "good" were considered to be acceptable.

[0126] Dicing workpiece: 10 silicon wafers (wafer diameter 12 inches, wafer thickness 400 μm)

[0127] Dicing blade: diameter 55 mm, actual thickness 32.5 μm, diamond abrasive grain size 2000 nm, concentration 70, bond material is Ni.

[0128] Dicing conditions: cutting depth 400 μm, feed rate 30 mm / s, spindle rotation speed 30,000 / min, processing time 7 hours, processing water supply rate 2 L / min

[0129] [Dicing blade reliability] Good: Blade wear is less than 20 μm. Good: Blade wear is 20 μm or more and less than 40 μm. Poor: Blade wear is 40 μm or more.

[0130] As shown in Table 1, in Examples 1 to 6, the dissolution rate of Ni was 0.002 to 0.003 nm / min, which was a low value. As a result, it was determined that the consumption of the binder in the dicing blade was small. Furthermore, when the surface roughness of the nickel film was observed, some deterioration in surface roughness due to etching was confirmed, but it was determined that this was not a problem. Furthermore, the charging potential observed was -1 V in all cases. This value was also within the acceptable range.

[0131] On the other hand, as shown in Table 1, in Comparative Example 1, the dissolution rate was a slightly high value of 0.004 nm / min, and it was determined that the binder was consumed significantly in the dicing blade. Furthermore, when the surface roughness of the nickel film was observed, it was confirmed that the surface roughness had deteriorated due to etching, and it was determined to be defective. Furthermore, the charging potential was −15 V, raising concerns about electrostatic damage to semiconductor elements.

[0132] In Comparative Example 2, the dissolution rate was 0.005 nm / min, which was a slightly high value, and it was determined that the binder was consumed significantly in the dicing blade. Furthermore, when the surface roughness of the nickel film was observed, it was confirmed that the surface roughness had worsened due to etching, and it was determined to be defective.

[0133] [Table 1]

[0134] (Solubility in Cu film) A rectangular test piece measuring 20 mm × 20 mm was cut from a 300 mm diameter Cu film-coated substrate. This test piece was immersed in the adjusted water of Examples 1 to 4 and Comparative Examples 1 and 2 at 23°C for 20 minutes. After immersion, the surface of the Cu film on the test piece was observed with an atomic force microscope (AFM) to confirm the surface roughness. The amount of Cu dissolved into the immersion solution was analyzed by inductively coupled plasma mass spectrometry (ICP-MS), and the Cu dissolution rate was calculated from the amount of Cu dissolved by immersion. Furthermore, the charged potential of the test piece after immersion was measured using a surface electrometer. The results are shown in Table 2.

[0135] The evaluation criteria for the surface roughness of the Cu film and the reliability of the dicing blade were the same as those for the nickel film.

[0136] As shown in Table 2, in Examples 1 to 4, the dissolution rate of Cu was low, ranging from 0.001 to 0.005 nm / min. As a result, it was determined that the consumption of the binder in the dicing blade was small. Furthermore, when the surface roughness of the Cu film was observed, some deterioration in surface roughness due to etching was confirmed, but it was determined that this was not a problem. Furthermore, the charging potential observed was -1 V in all cases. This value was also within the acceptable range.

[0137] On the other hand, as shown in Table 2, in Comparative Example 1, the dissolution rate was a fairly high value of 0.05 nm / min, and it was determined that the consumption of the binder in the dicing blade was extremely large. Furthermore, when the surface roughness of the Cu film was observed, it was confirmed that the surface roughness had deteriorated due to etching, and it was determined to be defective. Furthermore, the charging potential was -15 V, raising concerns about electrostatic damage to the semiconductor element.

[0138] In Comparative Example 2, the dissolution rate was 0.1 nm / min, which was a slightly high value, and it was determined that the binder was consumed significantly in the dicing blade. Furthermore, when the surface roughness of the Cu film was observed, it was confirmed that the surface roughness had worsened due to etching, and it was determined to be defective.

[0139] [Table 2]

[0140] (Solubility in Co film) A rectangular test piece measuring 20 mm × 20 mm was cut from a 300 mm diameter Co film-coated substrate. This test piece was immersed in the adjusted water of Examples 1 to 6 and Comparative Examples 1 and 2 at 23°C for 20 minutes. The surface of the Co film on the test piece after immersion was observed with an atomic force microscope (AFM) to confirm the surface roughness. The amount of Co dissolved into the immersion solution was analyzed by inductively coupled plasma mass spectrometry (ICP-MS), and the Co dissolution rate was calculated from the amount of Co dissolved by immersion. Furthermore, the charged potential of the test piece after immersion was measured using a surface electrometer. The results are shown in Table 3.

[0141] The evaluation criteria for the surface roughness of the Co film and the reliability of the dicing blade were the same as those for the nickel film.

[0142] As shown in Table 3, in Examples 1 to 6, the Co dissolution rate was low, ranging from 0.005 to 0.008 nm / min. As a result, it was determined that the binder wear in the dicing blade was small. Furthermore, when the surface roughness of the Co film was observed, some deterioration in surface roughness due to etching was confirmed, but this was determined to be negligible. Furthermore, the charging potential was observed to be -1 V in all cases. This value was also within the acceptable range.

[0143] On the other hand, as shown in Table 3, in Comparative Example 1, the dissolution rate was a fairly high 0.3 nm / min, and it was determined that the binder wear in the dicing blade was extremely large. Furthermore, when the surface roughness of the Co film was observed, it was confirmed that the surface roughness had worsened due to etching, and it was determined to be defective. Furthermore, the charging potential was -15 V, raising concerns about electrostatic damage to semiconductor elements.

[0144] In Comparative Example 2, the dissolution rate was 0.5 nm / min, which was quite high, and it was determined that the binder was consumed significantly in the dicing blade. Furthermore, when the surface roughness of the Co film was observed, it was confirmed that the surface roughness had worsened due to etching, and it was determined to be defective.

[0145] [Table 3] [Explanation of symbols]

[0146] 1, 11, 21...pH / oxidation-reduction potential adjusted water production device, 2...supply line, 3...platinum group metal supported resin column (hydrogen peroxide removal mechanism), 4, 14, 24...pH adjuster injection line (pH adjustment device), 5...deaeration membrane device, 6, 16...gas dissolution device, 7...storage tank.

Claims

1. a degassing membrane device having a degassing membrane for removing gases dissolved as impurities from pure water; a pH adjusting device for adjusting the pH of the pure water; a dissolving film device having a gas dissolving film that dissolves an inert gas in pure water; pH and oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential at 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) is produced, A supply flow path that supplies the produced pH / oxidation-reduction potential adjusted water as cooling water for a dicing blade in which diamond abrasive grains are fixed with a binder containing at least one selected from the group consisting of nickel, cobalt, and copper; or The pH / oxidation-reduction potential adjusted water producing apparatus is provided with a supply flow path for supplying the produced pH / oxidation-reduction potential adjusted water as cooling water in a dicing step of a semiconductor manufacturing process.

2. the pH adjusting device, the degassing membrane device, and the dissolving membrane device are arranged in this order along the direction of flow of pure water; 2. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 1, wherein the pH adjuster adds a liquid pH adjuster to the pure water.

3. 3. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 2, wherein the pH adjuster is an aqueous solution of at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine.

4. The degassing membrane device and the dissolving membrane device are arranged in this order along the direction of flow of pure water, the pH adjusting device supplies a gaseous pH adjusting agent to the gas dissolution film of the dissolution film device; 2. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 1, wherein the dissolving film device dissolves at least the pH adjuster in the pure water.

5. 5. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 4, wherein the pH adjuster is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine.

6. 6. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 5, wherein the pH adjuster further contains an inert gas.

7. a degassing membrane device equipped with a degassing membrane that removes gases dissolved as impurities from pure water; a pH adjusting device for adjusting the pH of the pure water; pH and oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential at 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) is produced, A supply flow path that supplies the produced pH / oxidation-reduction potential adjusted water as cooling water for a dicing blade in which diamond abrasive grains are fixed with a binder containing at least one selected from the group consisting of nickel, cobalt, and copper; or The pH / oxidation-reduction potential adjusted water producing apparatus is provided with a supply flow path for supplying the produced pH / oxidation-reduction potential adjusted water as cooling water in a dicing step of a semiconductor manufacturing process.

8. the degassing membrane device and the pH adjusting device are arranged in this order along the direction of flow of pure water; 8. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 7, wherein the pH adjuster dissolves at least one pH adjuster selected from a gas and a liquid in the pure water.

9. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 8, wherein the pH adjuster is an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine.

10. 9. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 8, wherein the pH adjuster comprises at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas.

11. 11. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 1, which produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at 25°C, and a dissolved oxygen concentration of 50 ppb or less at 25°C.

12. 11. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 1, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential of −0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at pH 9 to 14 and 25°C, and a hydrogen peroxide concentration of 30 ppb or less.

13. 11. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 1, which produces pH / oxidation-reduction potential adjusted water having a pH of 9 to 14, an oxidation-reduction potential of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at 25°C, a dissolved oxygen concentration of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less at 25°C.

14. 11. The pH / oxidation-reduction potential adjusted water producing apparatus according to claim 1, further comprising a hydrogen peroxide removal mechanism provided upstream of the degassing membrane device for removing hydrogen peroxide dissolved as an impurity from the pure water.

15. a pH adjusting step of adjusting the pH of the pure water by adding a liquid pH adjuster to the pure water; a degassing step in which gases dissolved as impurities are removed from the pure water using a degassing membrane; This is followed by a gas dissolution process in which an inert gas is dissolved in pure water using a gas dissolution membrane. pH / oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential at 25°C of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) is produced; The pH / oxidation-reduction potential adjusted water is used as cooling water for a dicing blade in which diamond abrasive grains are fixed by a metal layer containing at least one selected from the group consisting of nickel, cobalt, and copper, or The method for producing pH / oxidation-reduction potential adjusted water is used as cooling water in a dicing step in the semiconductor manufacturing process.

16. 16. The method for producing pH / oxidation-reduction potential adjusted water according to claim 15, wherein the pH adjuster is an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine.

17. a degassing step in which gases dissolved as impurities in the pure water are removed from the pure water using a degassing membrane; and a step of supplying a gaseous pH adjuster to the pure water through the gas dissolution membrane to adjust the pH of the pure water. pH / oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential at 25°C of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) is produced; The pH / oxidation-reduction potential adjusted water is used as cooling water for a dicing blade in which diamond abrasive grains are fixed by a metal layer containing at least one selected from the group consisting of nickel, cobalt, and copper, or The method for producing pH / oxidation-reduction potential adjusted water is used as cooling water in a dicing step in the semiconductor manufacturing process.

18. 18. The method for producing pH / oxidation-reduction potential adjusted water according to claim 17, wherein the pH adjuster is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine.

19. The method for producing pH / oxidation-reduction potential adjusted water according to claim 18, wherein the pH adjuster further contains an inert gas.

20. a degassing step in which gases dissolved as impurities in the pure water are removed from the pure water using a degassing membrane; a pH adjusting step of adjusting the pH of the pure water by adding at least one pH adjuster selected from a gas and a liquid to the pure water, pH / oxidation-reduction potential adjusted water having a pH of 9 to 14 and an oxidation-reduction potential at 25°C of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl) is produced; The pH / oxidation-reduction potential adjusted water is used as cooling water for a dicing blade in which diamond abrasive grains are fixed by a metal layer containing at least one selected from the group consisting of nickel, cobalt, and copper, or The method for producing pH / oxidation-reduction potential adjusted water is used as cooling water in a dicing step in the semiconductor manufacturing process.

21. 21. The method for producing pH / oxidation-reduction potential adjusted water according to claim 20, wherein the pH adjuster is an aqueous solution containing at least one selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, tetrahydroammonium, choline, methylamine, dimethylamine, and trimethylamine.

22. 21. The method for producing pH / oxidation-reduction potential adjusted water according to claim 20, wherein the pH adjuster comprises at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas.

23. 23. The method for producing pH / oxidation-reduction potential adjusted water according to any one of claims 15 to 22, wherein the method produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at pH 9 to 14 and 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) and a dissolved oxygen concentration at 25°C of 50 ppb or less.

24. 23. A method for producing pH / oxidation-reduction potential adjusted water according to any one of claims 15 to 22, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at pH 9 to 14 and 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) and a hydrogen peroxide concentration of 30 ppb or less.

25. 23. A method for producing pH / oxidation-reduction potential adjusted water according to any one of claims 15 to 22, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at pH 9 to 14 and 25°C of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl), a dissolved oxygen concentration at 25°C of 50 ppb or less, and a hydrogen peroxide concentration of 30 ppb or less.

26. 16. The method for producing pH / oxidation-reduction potential adjusted water according to claim 15, further comprising a hydrogen peroxide removal step of removing hydrogen peroxide dissolved as an impurity in the pure water from the pure water prior to the pH adjustment step.

27. 21. The method for producing pH / oxidation-reduction potential adjusted water according to claim 17 or claim 20, further comprising a hydrogen peroxide removal step of removing hydrogen peroxide dissolved as an impurity in the pure water from the pure water prior to the degassing step.

28. A method for manufacturing a semiconductor device, in which the pH / oxidation-reduction potential adjusted water produced by the method for producing pH / oxidation-reduction potential adjusted water described in any one of claims 15 to 22 is used as cooling water for a dicing blade in which diamond abrasive grains are fixed by a metal layer containing at least one selected from the group consisting of nickel, cobalt, and copper.

29. A method for manufacturing a semiconductor device, in which the pH / oxidation-reduction potential adjusted water manufactured by the method for manufacturing pH / oxidation-reduction potential adjusted water according to any one of claims 15 to 22 is used as cooling water in a dicing process of a semiconductor manufacturing process.

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