Apparatus for producing ph / redox potential-adjusted water, method for producing ph / redox potential-adjusted water, and method for producing semiconductor device

Abstract

This apparatus for producing pH / redox potential-adjusted water comprises: a degassing membrane device having a degassing membrane that removes dissolved gas, as an impurity, from pure water; a pH adjustment device that adjusts the pH of the pure water; and a dissolution membrane device that has a gas dissolution membrane for dissolving an inert gas in the pure water. The pH / redox potential-adjusted water production apparatus produces pH / redox potential-adjusted water that has a redox potential equal to or greater than -0.40 V and less than +0.40 V (vs Ag / AgCl) at a pH of 9 to 14 and 25°C.

Description

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

[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. This application claims priority based on Japanese Patent Application No. 2024-022868, filed February 19, 2024, the contents of which are incorporated herein by reference.

[0002] Among semiconductor manufacturing processes, a dicing process is one of the post-processes for assembling semiconductor chips. The dicing process is a process in which a semiconductor substrate on which a large number of integrated circuits (ICs) are formed is cut into individual IC chips. In the dicing process, for example, the semiconductor substrate after the integrated circuits are formed is attached to a dicing tape, the semiconductor substrate is cut into individual integrated circuits, and then individual IC chips are manufactured 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. 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] By the way, the dicing blade used in blade dicing has a disc-shaped blade with a thickness of about 15 μm, and diamond abrasive grains are fixed to the outer peripheral end 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 they are used, the outer peripheral end surface of the blade is physically worn, which leads to a decrease in dicing performance, so they are regularly replaced and 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.

[0007] Japanese Patent Application Publication No. 2022-78489

[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.

[0009] To solve the above problems, the present invention employs the following configuration: [1] An apparatus for producing pH / oxidation-reduction potential adjusted water, comprising: a degassing membrane device having a degassing membrane that removes gases dissolved as impurities from pure water; a pH adjustment device that adjusts the pH of the pure water; and a dissolution membrane device having a gas dissolution membrane that dissolves an inert gas in the pure water, and producing pH / oxidation-reduction potential adjusted water having a redox potential of -0.40 V or greater and less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and at 25°C. [2] The pH adjustment device, degassing membrane device, and dissolution membrane device are arranged in this order along the direction of flow of pure water, and the pH adjustment device adds a liquid pH adjuster to the pure water. [3] The apparatus for producing pH / oxidation-reduction potential adjusted water according to [1], wherein the pH adjustment device, degassing membrane device, and dissolution membrane device are arranged in this order along the direction of flow of pure water, and the pH adjustment 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 pH / oxidation-reduction potential adjusted water producing apparatus according to [1], wherein the degassing membrane device and the dissolution membrane device are arranged in this order along the direction of flow of pure water, the pH adjuster supplies a gaseous pH adjuster to the gas dissolution membrane of the dissolution membrane device, and the dissolution membrane 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 pH / oxidation-reduction potential adjusted water producing device comprising: a degassing membrane device equipped with a degassing membrane that removes gases dissolved as impurities from pure water; and a pH adjusting device that adjusts the pH of pure water, the device producing 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 and less than +0.40 V (vs. Ag / AgCl).[8] The pH / oxidation-reduction potential adjusted water producing apparatus according to [7], wherein the degassing membrane device and the pH adjuster are arranged in this order along the direction of flow of pure water, and 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 contains at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine, and an inert gas.

[11] The 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 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 dissolved oxygen concentration of 50 ppb or less at 25° C.

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

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

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

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

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

[10] , which is provided with a supply flow path that supplies the produced pH / oxidation-reduction potential adjusted water as cooling water in a dicing step of a semiconductor manufacturing process.

[17] A method for producing pH / oxidation-reduction potential adjusted water, which produces pH / oxidation-reduction potential adjusted water having a redox potential of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and 25°C, by sequentially carrying out the following steps: 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 of removing gases dissolved as impurities from the pure water using a degassing membrane, and a gas dissolution step of dissolving an inert gas into the pure water using a gas dissolution membrane.

[18] The 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 method for producing pH / oxidation-reduction potential adjusted water, which produces pH / oxidation-reduction potential adjusted water having a redox potential of -0.40 V or greater and less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and 25°C, by sequentially performing a degassing step of removing gases dissolved as impurities from the pure water using a degassing membrane and a step of adjusting the pH of the pure water by supplying a gaseous pH adjuster to the pure water using a gas dissolution membrane.

[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 method for producing pH / oxidation-reduction potential adjusted water, the method comprising the steps of: a degassing step of removing gases dissolved as impurities from the pure water using a degassing membrane; and a pH adjustment 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, thereby producing pH / oxidation-reduction potential adjusted water having a redox potential of −0.40 V or greater and 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] A method for producing pH / oxidation-reduction potential adjusted water according to

[22] , wherein the pH adjuster contains 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 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 dissolved oxygen concentration of 50 ppb or less at 25° C.

[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 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.

[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 an oxidation-reduction potential of −0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at a pH of 9 to 14 and 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] A method for producing pH / oxidation-reduction potential adjusted water according to

[17] , which comprises, before the pH adjustment step, a hydrogen peroxide removal step of removing hydrogen peroxide dissolved as an impurity in the pure water from the pure water.

[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 from the pure water.

[30] A method for producing semiconductor device, wherein the pH / oxidation-reduction potential adjusted water produced by the method for producing pH / oxidation-reduction potential adjusted water according to 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 producing semiconductor device, wherein the pH / oxidation-reduction potential adjusted water produced by the method for producing pH / oxidation-reduction potential adjusted water according to any one of

[17] to

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

[0010] The apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention can produce pH / oxidation-reduction potential adjusted water that has a low concentration of dissolved gases, a pH adjusted to 9 to 14, and a stabilized pH and oxidation-reduction potential due to the dissolution of an inert gas. Such pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of a dicing blade. 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 apparatus for producing pH / oxidation-reduction potential adjusted water 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 does not fluctuate even when the pure water after pH adjustment is degassed, so pH / oxidation-reduction potential adjusted water with stabilized pH and oxidation-reduction potential can be produced.

[0012] According to the pH / oxidation-reduction potential adjusted water manufacturing apparatus 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, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted 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 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.

[0014] According to the apparatus for producing pH / oxidation-reduction potential adjusted water of the present invention, the gas dissolving 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 a dicing blade. 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 apparatus for producing pH / oxidation-reduction potential adjusted water 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 produced.

[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 pH / oxidation-reduction potential adjusted water manufacturing apparatus 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 the dicing blade, and therefore can produce pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing, which can reduce 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 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, 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 the dicing blade, thereby reducing the frequency of dicing blade replacement, and can produce pH / oxidation-reduction potential adjusted water for use as cooling water in blade dicing.

[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 at 25°C of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl), 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 the dicing blade, 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 that supplies 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 the binder of the dicing blade from dissolving 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 replacing dicing blades.

[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 does not fluctuate even when the pure water after pH adjustment is degassed, so 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, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted 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 the pure water that has been degassed in advance, 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 pH / oxidation-reduction potential adjusted water manufacturing apparatus of the present invention, dissolved gases in the 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, so that the pH of the pH / oxidation-reduction potential adjusted water can be adjusted 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 at 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.This pH / oxidation-reduction potential adjusted water can suppress the dissolution of various metals that make up the binder of a dicing blade, 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 and 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 a dicing blade, 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 at 25°C of -0.40 V or more but less than +0.40 V (vs. Ag / AgCl), 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 a dicing blade, 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.

[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 process of the semiconductor manufacturing process, thereby making it possible to reduce the frequency of replacing the dicing blade.

[0040] 1 is a schematic diagram showing a pH / oxidation-reduction potential adjusted water manufacturing apparatus according to a first embodiment of the present invention, 2 is a schematic diagram showing a pH / oxidation-reduction potential adjusted water manufacturing apparatus according to a second embodiment of the present invention, and 3 is a schematic diagram showing a pH / oxidation-reduction potential adjusted water manufacturing apparatus according to a third embodiment of the present invention.

[0041] The pH / oxidation-reduction potential adjusted water production apparatus of the present invention includes 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 the pure water. The pH / oxidation-reduction potential adjusted water production apparatus of the present invention may further include 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 pH / oxidation-reduction potential adjusted water production apparatus 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 greater but less than +0.40 V (vs. Ag / AgCl) at 25°C. The pH / oxidation-reduction potential adjusted water production apparatus and production method according to embodiments of the present invention are described in detail below with reference to the drawings.

[0042] [First embodiment] <pH / oxidation-reduction potential adjusted water manufacturing apparatus> Figure 1 shows a pH / oxidation-reduction potential adjusted water manufacturing apparatus according to a first embodiment of the present invention. The pH / oxidation-reduction potential adjusted water manufacturing apparatus 1 shown in Figure 1 is provided with a pure water W supply line 2, a platinum group metal-supported resin column 3 serving as a hydrogen peroxide removal mechanism, a pH adjuster injection line 4 (pH adjuster), a degassing membrane device 5 that degasses dissolved gases in the pure water, a gas dissolver 6 that dissolves an inert gas in the pure water, and a storage tank 7 that stores the adjusted pH / oxidation-reduction potential adjusted water (hereinafter sometimes referred to as adjusted water).

[0043] The platinum group metal-supported resin column 3, 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.

[0044] In this embodiment, examples of platinum group metals supported on the platinum group metal-supported resin used in 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 with two or more, or as an alloy of two or more, or as a purified product of a naturally occurring mixture can be used without separating the individual elements. Among these, platinum, palladium, and platinum / palladium alloys, either alone or as a mixture of two or more of these, are preferred due to their strong catalytic activity. Nanoparticles of these metals can also be particularly preferred.

[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, anion exchange resins are 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 groups of the anion exchange resin are 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 Figure 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 purge the pH adjuster tank 4A with an inert gas or to provide a mechanism for removing dissolved oxygen from the pH adjuster in the tank using a degassing membrane.

[0048] The liquid supply mechanism 4B can use a pump such as a diaphragm pump to supply the liquid pH adjuster. ２ A pressure pump can also be suitably used in which the agent is placed in the container together with an inert gas such as gas, and the agent 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, polyurethane, etc. Various commercially available degassing membranes can be used.

[0050] The gas dissolving device 6 is disposed after the degassing membrane device 5. The gas dissolving device 6 is provided with a gas dissolving membrane, and the gas phase chamber side of the gas dissolving membrane is filled with N 2 as an inert gas. ２ The gas-dissolving membrane device 6 is connected to a gas source. The gas-dissolving membrane device 6 is configured to have the adjusting water W1 flow on one side (liquid phase side) of the gas-dissolving membrane and the N2 gas flow on the other side (gas phase side). ２ By supplying the gas, an inert gas is dissolved in the adjusted water W1. ２ The gas is not limited to argon and helium, and other gases 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 the dicing device is a dicing device that cuts semiconductor substrates with a dicing blade. An example of the dicing blade is a disc-shaped blade with diamond abrasive grains fixed to the outer peripheral end surface with a binder. Examples of the binder for the diamond abrasive grains include those made of metals such as nickel, cobalt, copper, tin, silver, and tungsten.

[0053] In this embodiment, downstream of the gas dissolver 6 on the supply line 2, for example in the storage tank 7, 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 3 based on the values ​​measured by the pH meter and ORP meter.

[0054] <Pure Water> In this embodiment, the pure water W serving as raw water is preferably ultrapure water having, for example, a resistivity of 18.1 MΩ cm or more, fine particles having a particle size of 50 nm or more and 1,000 particles / L or less, viable bacteria of 1 particle / 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 this embodiment, the pure water W serving as raw water may contain more than 30 ppb of hydrogen peroxide, 50 ppb or more of dissolved oxygen, and a pH of less than 9.

[0055] <pH Adjuster> In this embodiment, there are no particular limitations on the pH adjuster injected from the pH adjuster tank 4A. To adjust the pH of the adjusted 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 adjusted water is used as cooling water in the dicing process, it is preferable to make the adjusted water alkaline to prevent dissolution of the metal in the binder. However, alkali metal solutions such as sodium hydroxide may be inappropriate because they contain metal components. Therefore, in this embodiment, it is most preferable to use ammonia, tetrahydroammonium, choline, methylamine, dimethylamine, trimethylamine, or the like.

[0056] <Method for Producing pH / oxidation-reduction potential adjusted water> A method for producing pH / oxidation-reduction potential adjusted water using the pH / oxidation-reduction potential adjusted water producing apparatus 1 of this embodiment having the above-described configuration will be described below.

[0057] In this embodiment, a hydrogen peroxide removal step, a pH adjustment step, a degassing step, a gas dissolving step, and a supplying step are performed.

[0058] The hydrogen peroxide removal process is a process of removing hydrogen peroxide dissolved in the pure water W to reduce the hydrogen peroxide concentration to 30 ppb or less. However, the hydrogen peroxide removal process is not necessarily required in this embodiment. If the hydrogen peroxide concentration of the pure water W is 30 ppb or less, the hydrogen peroxide removal process may be omitted. Pure water with a 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). Furthermore, the pH adjustment process adjusts the pH of the pure water after the hydrogen peroxide removal process to a range of 9 to 14. Furthermore, the degassing process removes dissolved gases contained in the pure water to reduce the dissolved oxygen concentration to 50 ppb or less. Furthermore, the gas dissolution process stabilizes the pH and oxidation-reduction potential of the adjusted water by dissolving an inert gas in the pure water. The supply process supplies the adjusted water W1 to the semiconductor manufacturing process via a supply line 2. Each process will be described in detail below.

[0059] Pure water W as raw water generally contains hydrogen peroxide at a 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 in advance. 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 from the pure water W, i.e., 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 adjusted water W1 after pH adjustment 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 of 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 deaeration step using a gas dissolution membrane device 6 to stabilize the properties of the adjusted water W1, thereby producing stabilized adjusted water W1. It is preferable that the inert gas is dissolved up to a saturated amount.

[0063] Once the 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 regulated 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 regulated water W1 may also have a dissolved oxygen concentration of 50 ppb or less at 25°C. The produced regulated water W1 may also have a hydrogen peroxide concentration of 30 ppb or less. The produced regulated water W1 may also have a pH of 9 to 14, a 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 of 50 ppb or less at 25°C, and a hydrogen peroxide concentration of 30 ppb or less.

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

[0066] (Example of Supply of pH / Oxidation-Reduction Potential Adjusted Water) Hereinafter, a case where the adjusted water W1 produced as described above is used as cooling water in a dicing process will be described.

[0067] In this embodiment, the adjusted water W1 is supplied to the semiconductor manufacturing process via the supply line 2. Here, an example of the semiconductor manufacturing process is a dicing device that cuts a semiconductor substrate using a dicing blade. 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, conditioned water is supplied as cooling water. The conditioned water has a pH of 9 to 14 and an oxidation-reduction potential at 25°C of -0.40 V or greater but less than +0.40 V (vs. Ag / AgCl). Furthermore, the conditioned water has a dissolved oxygen concentration of 50 ppb or less and a hydrogen peroxide concentration of 30 ppb or less at 25°C. Because such conditioned water is alkaline and has an oxidation-reduction potential in the range of ±0.40 V, it does not dissolve the metals that make up the binder of the dicing blade. This prevents deterioration of the dicing blade and reduces the frequency of dicing blade replacement.

[0069] Second Embodiment <pH / oxidation-reduction potential adjusted water manufacturing apparatus> Fig. 2 shows a pH / oxidation-reduction potential adjusted water manufacturing apparatus 11 according to a second embodiment of the present invention. In Fig. 2, the same components as those in the first embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted.

[0070] The pH / oxidation-reduction potential adjusted water producing apparatus 11 shown in Figure 2 is provided with a degassing membrane device 5 that degasses dissolved gases in the pure water and a gas dissolver 16 that dissolves gases in the pure water, on a supply line 2 for pure water W. The pH / oxidation-reduction potential adjusted water producing apparatus 11 shown in Figure 2 is also provided with a pH adjuster injection line 14 (pH adjuster) that supplies a pH adjuster to the gas dissolver 16.

[0071] 2 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 pH / oxidation-reduction potential adjusted water (adjusted water) downstream of the gas dissolving device 16 may be provided.

[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 that of the first embodiment.

[0074] The gas dissolver 16 is disposed downstream of the degassing membrane device 5. The gas dissolver 16 is provided 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 on 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 in the pure water W together with the pH adjuster. Examples of the inert gas include N ２ In addition to the gas, argon, helium, etc. can be suitably used. The inert gas should be 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 the 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 apparatus 16 along with the gaseous pH adjuster. That is, the pH adjuster injection line 14 can supply a mixed gas of the pH adjuster and the inert gas to the gas dissolution apparatus 16. A pH adjuster tank filled with the pH adjuster, an inert gas source, a gas pressure mechanism for pressurizing and supplying the pH adjuster and the inert gas, and the like may be provided upstream of the pH adjuster injection line 14.

[0076] The storage tank may be 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 a 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 first embodiment.

[0080] <pH Adjuster> In this embodiment, the pH adjuster injected through the pH adjuster injection line 14 is not particularly limited as long as it is a gas, and at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine can be used to adjust the pH of the pure water to 9 to 14. The pH adjuster can also be mixed with an inert gas such as nitrogen, argon, or helium. All of these pH adjusters are supplied in a gaseous state.

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

[0082] In this embodiment, a degassing step, a gas dissolving step in which a pH adjuster is dissolved, and a supplying step are performed. Also, a hydrogen peroxide removing step may be performed before the degassing step.

[0083] The hydrogen peroxide removal process is a process of removing hydrogen peroxide dissolved in the pure water W to reduce the hydrogen peroxide concentration to 30 ppb or less. However, the hydrogen peroxide removal process is not necessarily required in this embodiment. If the hydrogen peroxide concentration of the pure water W is 30 ppb or less, the hydrogen peroxide removal process may be omitted. Pure water with a 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 process removes dissolved gases contained in the pure water to reduce the dissolved oxygen concentration to 50 ppb or less. The gas dissolution process adjusts the pH of the pure water by dissolving a pH adjuster in the pure water. The pH and oxidation-reduction potential of the pH-adjusted adjusted water are stabilized by supplying an inert gas. The supply process supplies the adjusted water W1 to the semiconductor manufacturing process via a supply line 2. Each process is described in detail below.

[0084] Pure water W as raw water generally contains hydrogen peroxide at a 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 in advance. 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 from 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 the liquid-phase chamber and the 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 will be degassed, and the pH of the adjusted water may fall outside the range of 9 to 14.

[0087] Next, in the gas dissolution process, a gaseous pH adjuster is supplied to the gas dissolution membrane through the pH adjuster injection line 14, and the gaseous pH adjuster is dissolved in the pure water through the gas dissolution membrane to adjust the pH of the pure water. The amount of pH adjuster added can be appropriately determined 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 process is to be alkaline, an amount sufficient to bring the pH of the pure water to a range of 9 to 14 can be added. Additionally, an inert gas may be dissolved in the pure water W along with the pH adjuster. Dissolving the inert gas prevents the incorporation of oxygen and carbon dioxide and stabilizes the pH and redox potential. The inert gas should be dissolved to a saturated amount.

[0088] Once the adjusted water W1 is produced in this manner, 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 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 amount of pH adjuster added from the pH adjuster injection line 14 and the platinum group metal-supported resin column are controlled by a control device 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.

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

[0090] 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.

[0091] [Third Embodiment] <pH / oxidation-reduction potential adjusted water manufacturing apparatus> Figure 3 shows a pH / oxidation-reduction potential adjusted water manufacturing 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 designated by the same reference numerals, and detailed description thereof will be omitted. The pH / oxidation-reduction potential adjusted water manufacturing 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) downstream of the pH adjustment device 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 that of 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. In addition, the pH adjuster is supplied to the pH adjuster tank 24A by N ２ A pressure pump can also be suitably used in which the agent is placed in the container together with an inert gas such as gas, and the agent is pushed out by the pressure of the inert gas.

[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 use point UP. An example of the use point UP to which the supply line 2 reaches is a dicing device that cuts a semiconductor substrate with a dicing blade. 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 a 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.

[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, the pH adjuster injected through the pH adjuster injection line 24 is not particularly limited as long as it is at least one pH adjuster selected from the group consisting of gases and liquids. Specifically, 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 as a liquid pH adjuster for adjusting the pH of pure water to 9 to 14. Furthermore, a gaseous pH adjuster 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 pH / oxidation-reduction potential adjusted water producing apparatus 21 of this embodiment having the above-described configuration will be described below.

[0104] In this embodiment, a degassing step for degassing the pure water, a pH adjusting step for adjusting the pH of the pure water, and a supplying step are performed. Furthermore, a hydrogen peroxide removing step may be performed before the degassing step.

[0105] The hydrogen peroxide removal process is a process of removing hydrogen peroxide dissolved in the pure water W to reduce the hydrogen peroxide concentration to 30 ppb or less. However, the hydrogen peroxide removal process is not necessarily required in this embodiment. If the hydrogen peroxide concentration of the pure water W is 30 ppb or less, the hydrogen peroxide removal process may be omitted. Pure water with a 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 process removes dissolved gases contained in the pure water to reduce the dissolved oxygen concentration to 50 ppb or less. The pH adjustment process adjusts the pH of the pure water by adding at least one pH adjuster selected from gases and liquids. Furthermore, the pH and oxidation-reduction potential of the pH-adjusted adjusted water are stabilized by supplying an inert gas. The supply process supplies the adjusted water W1 to a semiconductor manufacturing process via a supply line 2. Each process is described in detail below.

[0106] Pure water W as raw water generally contains hydrogen peroxide at a 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 in advance. 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 from 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 the liquid-phase chamber and the 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 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. 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.

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

[0114] [Production of Adjusted Water in Example 1] Using the pH / oxidation-reduction potential adjusted water production 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 ammonia / hydrogen peroxide solution (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 in Example 3] In the same manner as in Example 1, an aqueous ammonia / hydrogen peroxide solution (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 in Example 4] Using the pH / oxidation-reduction potential adjusted water production 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 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 the 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 in Example 5] Using the pH / oxidation-reduction potential adjusted water production 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. After that, an aqueous sodium hydroxide solution was added from the pH adjuster tank 24A to produce an aqueous sodium hydroxide / hydrogen peroxide solution (sodium hydroxide concentration: 1000 ppm, pH 12 (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: +0.05 V) as adjusted water W1.

[0119] [Production of Adjusted Water in Example 6] Using the pH / oxidation-reduction potential adjusted water production 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. After that, an aqueous sodium hydroxide solution was added from pH adjuster tank 24A to produce an aqueous sodium hydroxide / hydrogen peroxide solution (sodium hydroxide concentration: 5%, pH 14 (23°C), hydrogen peroxide concentration: 30 ppb, oxidation-reduction potential: -0.20 V) as adjusted water W1.

[0120] [Production of Adjusted Water in Comparative Example 1] Using the pH / oxidation-reduction potential adjusted water production 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 in Comparative Example 2] Using the pH / oxidation-reduction potential adjusted water production 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.Furthermore, carbon dioxide was added to the pure water from the 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) 20 mm x 20 mm rectangular test pieces were cut from a 300 mm diameter nickel-coated substrate. These test pieces were immersed in the adjusted waters of Examples 1 to 6 and Comparative Examples 1 and 2 at 23°C for 20 minutes. The surfaces of the nickel films on the test pieces after immersion were observed with an atomic force microscope (AFM) to confirm the surface roughness (double mean 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. The reliability of the dicing blade was evaluated based on this dissolution rate. Furthermore, the charging potential of the test pieces 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 mean surface roughness (Rms) of the nickel film is less than 1 nm. Good: The double mean surface roughness (Rms) of the nickel film is 1 nm or more and less than 3 nm. Poor: The double mean 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 waters of Examples 1 to 6 and Comparative Examples 1 and 2, based on the rate of dissolution of the nickel film, and the smaller the amount of wear, the better the reliability was evaluated. The dicing blade and dicing processing conditions were as follows. There is a correlation between the rate of dissolution of the nickel film and the amount of blade wear when dicing was performed under the conditions below, 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" and "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 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 amount is less than 20 μm. Fair: Blade wear amount is 20 μm or more and less than 40 μm. Poor: Blade wear amount is 40 μm or more.

[0130] As shown in Table 1, in Examples 1 to 6, the Ni dissolution rate was low, ranging from 0.002 to 0.003 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 nickel film was observed, some deterioration in surface roughness due to etching was confirmed, but this was determined to be negligible. 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 wear in the dicing blade was large. 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. Furthermore, the charging potential was −15 V, raising concerns about electrostatic breakdown of 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]

[0134] (Solubility in Cu Film) A rectangular test piece measuring 20 mm x 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. The surface of the Cu film on the test piece after immersion 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 Cu dissolution rate was low, ranging from 0.001 to 0.005 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 Cu film was observed, some deterioration in surface roughness due to etching was confirmed, but this was determined to be no 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 worsened due to etching, and it was determined to be defective. Furthermore, the charging potential was -15 V, raising concerns about electrostatic breakdown of 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 deteriorated due to etching, and it was determined to be defective.

[0139]

[0140] (Solubility in Co Film) A 20 mm × 20 mm rectangular test piece 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. After immersion, the surface of the Co film on the test piece 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 no problem. Furthermore, the charging potential observed was -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 value of 0.3 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 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 breakdown of the semiconductor element.

[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]

[0146] INDUSTRIAL APPLICABILITY The present invention has industrial applicability in that it can be used as cooling water for blade dicing to reduce the frequency of replacing dicing blades.

[0147] 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... degassing membrane device, 6, 16... gas dissolution device, 7... storage tank.

Claims

1. A pH / oxidation-reduction potential adjusted water manufacturing device comprising: a degassing membrane device having a degassing membrane that removes gases dissolved as impurities from pure water; a pH adjustment device that adjusts the pH of pure water; and a dissolving membrane device having a gas dissolving membrane that dissolves an inert gas in pure water, and which produces pH / oxidation-reduction potential adjusted water with 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).

2. A pH / oxidation-reduction potential adjusted water manufacturing apparatus as described in claim 1, wherein the pH adjustment device, the degassing membrane device, and the dissolving membrane device are arranged in this order along the direction of flow of pure water, and the pH adjustment device adds a liquid pH adjuster to the pure water.

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. A pH / oxidation-reduction potential adjusted water manufacturing apparatus as described in claim 1, wherein the degassing membrane device and the dissolution membrane device are arranged in this order along the direction of flow of pure water, the pH adjustment device supplies a gaseous pH adjuster to the gas dissolution membrane of the dissolution membrane device, and the dissolution membrane device dissolves at least the pH adjuster in the pure water.

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

7. A pH / oxidation-reduction potential adjusted water manufacturing device comprising a degassing membrane device equipped with a degassing membrane that removes gases dissolved as impurities from pure water, and a pH adjustment device that adjusts the pH of pure water, and which produces pH / oxidation-reduction potential adjusted water with 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).

8. A pH / oxidation-reduction potential adjusted water manufacturing apparatus as described in claim 7, wherein the degassing membrane device and the pH adjustment device are arranged in this order along the direction of flow of pure water, and the pH adjustment device dissolves at least one pH adjuster selected from a gas and a liquid into 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. 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. A pH / oxidation-reduction potential adjusted water manufacturing apparatus according to any one of claims 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 claims 1 to 10, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at a pH of 9 to 14 and at 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 claims 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 as described in any one of claims 1 to 10, wherein a hydrogen peroxide removal mechanism for removing hydrogen peroxide dissolved as an impurity from the pure water is provided upstream of the degassing membrane device.

15. A pH / oxidation-reduction potential adjusted water manufacturing device as described in any one of claims 1 to 10, which is provided with 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, copper, tin, silver, tungsten, and iron.

16. A pH / oxidation-reduction potential adjusted water manufacturing device as described in any one of claims 1 to 10, which is provided with a supply flow path that supplies the manufactured pH / oxidation-reduction potential adjusted water as cooling water in the dicing process of a semiconductor manufacturing process.

17. A method for 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 and less than +0.40 V (vs. Ag / AgCl) at 25°C, by sequentially carrying out the following steps: a pH adjustment step in which the pH of pure water is adjusted 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; and a gas dissolution step in which an inert gas is dissolved in the pure water using a gas dissolution membrane.

18. A method for producing pH / oxidation-reduction potential adjusted water as described in claim 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 method for 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 and less than +0.40 V (vs. Ag / AgCl) at 25°C, by sequentially carrying out 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 process in which a gaseous pH adjuster is supplied to the pure water using a gas dissolving membrane to adjust the pH of the pure water.

20. The method for producing pH / oxidation-reduction potential adjusted water according to claim 19, wherein the pH adjuster is at least one selected from the group consisting of ammonia, methylamine, dimethylamine, and trimethylamine.

21. A method for producing pH / oxidation-reduction potential adjusted water according to claim 20, wherein the pH adjuster further contains an inert gas.

22. A method for producing pH / oxidation-reduction potential adjusted water, which has a pH of 9 to 14 and an oxidation-reduction potential of -0.40 V or more and less than +0.40 V (vs. Ag / AgCl) at 25°C, by sequentially carrying out 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 adjustment process in which the pH of the pure water is adjusted by adding at least one pH adjuster selected from gases and liquids to the pure water.

23. A method for producing pH / oxidation-reduction potential adjusted water as described in claim 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. A method for producing pH / oxidation-reduction potential adjusted water according to claim 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 claims 17 to 24, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at a pH of 9 to 14 and at 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.

26. A method for producing pH / oxidation-reduction potential adjusted water according to any one of claims 17 to 24, which produces pH / oxidation-reduction potential adjusted water having an oxidation-reduction potential at a pH of 9 to 14 and at 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 claims 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 but 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.

28. A method for producing pH / oxidation-reduction potential adjusted water as described in claim 17, wherein a hydrogen peroxide removal step is carried out before the pH adjustment step to remove hydrogen peroxide dissolved as an impurity in the pure water from the pure water.

29. A method for producing pH / oxidation-reduction potential adjusted water as described in claim 19 or claim 22, wherein a hydrogen peroxide removal step is carried out before the degassing step to remove hydrogen peroxide dissolved in the pure water as an impurity 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 claims 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 according to any one of claims 17 to 24 is used as cooling water in the dicing process of the semiconductor manufacturing process.

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