Remover agent, remover agent for semiconductors, solvent for semiconductors, treatment liquid for semiconductors, and method for producing semiconductor element

Abstract

The present invention provides a remover agent for semiconductors, the remover agent being used for the purpose of removing a resin that has an ether bond from a substrate for semiconductors. This remover agent for semiconductors contains phosphoric acid; and the concentration of the phosphoric acid is 80% by weight to 88% by weight.

Description

Stripping agent, semiconductor stripping agent, semiconductor solvent, semiconductor processing solution, and method for manufacturing semiconductor element

[0001] The present invention relates to a stripping agent for a resin having an ether bond, a stripping agent for semiconductors, a solvent for semiconductors, and a processing liquid for semiconductors, and also to a method for manufacturing a semiconductor element using these.

[0002] In recent years, semiconductor elements have become increasingly sophisticated and highly integrated. Various resins are used in semiconductors for a variety of purposes. Examples of resins used in semiconductors include epoxy resins, phenolic resins, silicone resins, and acrylic resins for semiconductor encapsulation, and epoxy resins, urethane resins, silicone resins, and polyimide resins for conductive adhesives.

[0003] Forming semiconductor devices using these resins involves processing and removing the resin after molding. Many of these resins have high chemical resistance, making the technology for removing them from semiconductor substrates increasingly important. For example, epoxy resins after thermal curing have a three-dimensional network structure and excellent chemical resistance. The chemical resistance of epoxy resins varies primarily depending on the curing agent, with typical curing agents typically being amines or acid anhydrides. Chemical methods for removing the structures formed by these curing agents involve attacking the C-N bonds in amine-curing types and the ester bonds in acid anhydride-curing types.

[0004] Patent Document 1 describes a treatment liquid for a carbon material / acid anhydride-cured epoxy resin composite material, which is characterized by containing an alkali metal compound and a monoalcohol, and a separation method using the same.

[0005] Patent Document 2 describes a method for treating a composite material of inorganic material / cured epoxy resin, which is characterized by containing a catalyst for decomposing a cured epoxy resin and an organic solvent.

[0006] JP 2005-255899 A JP 2007-297641 A

[0007] Some epoxy resins are crosslinked by acids, lack highly chemically active bonds such as ester bonds, and have a three-dimensional structure formed by ether bonds. Patent Document 1 proposes a treatment solution containing an alkali metal compound and monoalcohols. The epoxy resin to be treated in this invention is an acid anhydride-cured epoxy resin, and its decomposition is thought to be due to transesterification and alcoholysis. Therefore, the inventors' investigations have revealed that removal efficiency is significantly reduced in the case of epoxy resins that have ether bonds and no ester crosslinks.

[0008] Furthermore, Patent Document 2 proposes a method of cleaving ether bonds using a cured epoxy resin decomposition catalyst. In this invention, it is stated that the cured epoxy resin to be treated preferably contains a halogen atom. It has been revealed that the removal efficiency is significantly reduced when used with an epoxy resin having a normal ether bond, in which the ortho-position of the benzene ring to which the ether group is bonded is not substituted with a halogen atom. Furthermore, when used in semiconductor devices, epoxy resins are sometimes used as adhesives between silicon wafers. However, the inventors' investigations have revealed that, because silicon reacts and corrodes under basic conditions, the use of the treatment solution described in Patent Document 2 can cause roughening of the Si substrate depending on the cured epoxy resin decomposition catalyst used.

[0009] Therefore, an object of the present invention is to provide a stripping agent (hereinafter referred to as stripping agent) that can efficiently strip a resin having an ether bond from a substrate at a high speed. Also, in the semiconductor field, an object of the present invention is to provide a semiconductor stripping agent (hereinafter also referred to as semiconductor stripping agent), a semiconductor solvent (hereinafter also referred to as solvent), and a semiconductor processing solution (hereinafter also referred to as processing solution) that can suppress corrosion of Si in a substrate when a resin having an ether bond contained in a semiconductor wafer is stripped from the substrate.

[0010] The present inventors have conducted extensive research to solve the above problems. They have found that resins having ether bonds can be rapidly stripped, dissolved, or treated from substrates by using a stripping agent, solvent, or treatment solution containing phosphoric acid. They have also found that the efficiency of the stripping agent can be improved by adding a stripping-promoting catalyst, which has led to the completion of the present invention.

[0011] That is, the present invention is configured as follows.

[0012] Item 1: A semiconductor stripper used to strip a resin having an ether bond from a semiconductor substrate, the semiconductor stripper containing phosphoric acid, the concentration of the phosphoric acid being 80% by weight or more and 88% by weight or less. Item 2: The semiconductor stripper according to Item 1, wherein the resin having an ether bond is an epoxy resin. Item 3: A semiconductor stripper used to strip a resin having an ether bond from a substrate, the stripper containing water, phosphoric acid, and a stripping-promoting catalyst. Item 4: The stripper according to Item 3, wherein the ratio of the stripping-promoting catalyst to the water is 0.0001 to 100,000 by weight. Item 5: The stripper according to Item 3 or 4, wherein the phosphoric acid comprises pyrophosphoric acid. Item 6: The stripper according to any one of Items 3 to 5, wherein the stripping-promoting catalyst is at least one selected from the group consisting of an oxidizing agent and an acid catalyst. Item 7: The stripper according to Item 6, wherein the oxidizing agent is at least one selected from the group consisting of hydrogen peroxide, a halogen oxygen acid, a hydrohalic acid, a halogen, and ozone. Item 8. The stripping agent according to Item 6, wherein the acid catalyst is at least one selected from the group consisting of hydrogen halide, sulfuric acid, nitric acid, and nitrous acid. Item 9. The stripping agent according to any one of Items 3 to 8, wherein the resin having an ether bond is an epoxy resin. Item 10. The stripping agent according to Item 6, wherein the oxidizing agent is hydrogen peroxide, and the ratio of the hydrogen peroxide to the water is 0.010 or more and 0.550 or less by weight. Item 11. The stripping agent according to any one of Items 3 to 10, wherein the stripping agent is a semiconductor stripper. Item 12. A semiconductor solvent used to dissolve a resin having an ether bond and strip it from a semiconductor substrate, the semiconductor solvent comprising phosphoric acid and a stripping-promoting catalyst. Item 13. A semiconductor processing liquid used to strip a resin having an ether bond from a semiconductor substrate, the semiconductor processing liquid comprising phosphoric acid and a stripping-promoting catalyst. Item 14. A method for producing a semiconductor element, comprising a stripping step of performing a treatment to strip a resin having an ether bond from a semiconductor substrate using the stripping agent according to Item 11, the semiconductor solvent according to Item 12, or the semiconductor treatment liquid according to Item 13.Item 15. A method for producing a semiconductor element, comprising a stripping step of performing a treatment to strip a resin having an ether bond from a semiconductor substrate using the stripping agent according to Item 11, the semiconductor solvent according to Item 12, or the semiconductor processing solution according to Item 13, wherein the treatment is performed at 20° C. or higher and 400° C. or lower.

[0013] By using the stripping agent, solvent, or treatment liquid of the present invention, it is possible to strip, dissolve, or treat a resin having an ether bond from a substrate efficiently at a high speed. Furthermore, when the stripping agent, solvent, or treatment liquid of the present invention is used for semiconductor applications, in addition to the above-mentioned effects, it is possible to maintain good smoothness of the Si surface after treatment, and it is possible to prevent a decrease in reliability in the production of semiconductor wafers.

[0014] The present invention will be described in detail below. The following description is an example (typical example) of the present invention, and the present invention is not limited thereto. Furthermore, the present invention can be implemented with any modifications within the scope of the gist thereof.

[0015] In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. Furthermore, in this specification, the expression "A or B" can be interpreted as "at least one selected from the group consisting of A and B." Furthermore, although multiple embodiments are described in this specification, various conditions in each embodiment can be applied to each other to the extent applicable. Furthermore, when describing component C contained in a stripper, solvent, or treatment liquid as "component C contains D," this can be interpreted as "the stripper, solvent, or treatment liquid contains at least D as component C."

[0016] (Removal Agent) In the release agent according to one embodiment of the present invention, the release agent for resins having ether bonds (hereinafter referred to as release agent) refers to a chemical solution that removes resins having ether bonds from a substrate, and is characterized by containing phosphoric acid. In the semiconductor field, the release agent refers to a chemical solution that removes resins having ether bonds contained in semiconductor wafers from a substrate. This release agent is used, for example, to remove an adhesive layer between a substrate and a resin, or to partially remove a resin from a resin layer. Therefore, the release agent according to this embodiment can be suitably used in each semiconductor manufacturing process in the semiconductor field.

[0017] (Semiconductor Solvent) The chemical solution (removal agent) according to this embodiment acts not only on the interface between the substrate and the resin having an ether bond but also on the ether bond within the resin molecule, and can therefore dissolve the resin by cleaving the ether bond. Therefore, the chemical solution according to this embodiment can also be used as a semiconductor solvent that dissolves resin whose ether bond has been cleaved.

[0018] (Semiconductor Treatment Solution) As described above, the chemical solution (stripper) according to this embodiment can be used as a semiconductor stripper (hereinafter referred to as a semiconductor stripper) that strips a resin having an ether bond from a semiconductor substrate, or as a semiconductor solvent (hereinafter referred to as a semiconductor solvent) that dissolves a resin having an ether bond. In addition, the chemical solution according to this embodiment is unlikely to corrode Si used as a substrate, and the smoothness of the Si is unlikely to be impaired by the chemical solution. Therefore, the chemical solution according to this embodiment can also be used as a semiconductor treatment solution for a substrate containing a resin having an ether bond. Note that, within the applicable range, the expressions "stripping," "removal," and "dissolution" can be used interchangeably.

[0019] The chemical solutions (strippers, solvents, or treatment solutions) will be specifically described below. As described above, these are characterized by containing phosphoric acid, and may contain any components other than phosphoric acid. However, from the viewpoint of enabling fast and efficient stripping, a configuration containing phosphoric acid at a specific concentration, a configuration containing phosphoric acid and a stripping-promoting catalyst, or a configuration further containing water are particularly preferred. However, the chemical solutions according to this embodiment are not limited to these configurations.

[0020] (Phosphoric acid) Phosphoric acid contained in the stripper, solvent, or treatment liquid has the chemical formula H ３ P.O. ４ orthophosphoric acid represented by the formula: pyrophosphoric acid (H ４ P ２ O ７ ), or triphosphate (H ５ P ３ O １０ ) and other polyphosphoric acids; trimetaphosphoric acid (H ３ P ３ O ９ ), or hyperpolyphosphate (HPO ３ ) ｎ metaphosphoric acid, etc.; monosuperphosphoric acid (H ３ P.O. ５ ), or disuperphosphate (H ４ P ２ O ８ ) and other superphosphates; salts of these phosphoric acids; diphosphorus pentoxide (P ２ O ５ ) ; or tetraphosphorus decaoxide (P ４ O １０ Although not particularly limited, solutions containing polyphosphoric acid such as orthophosphoric acid and pyrophosphoric acid, perphosphoric acid, diphosphorus pentoxide, or tetraphosphorus decaoxide are preferred from the viewpoint of the efficiency of removing resins having ether bonds. Furthermore, the phosphoric acid contained in the stripping agent, solvent, and treatment solution may be contained in a dissociated state. Furthermore, one type of phosphoric acid may be contained, or two or more types of phosphoric acid may be contained. For example, the inclusion of multiple types of phosphoric acid, such as orthophosphoric acid and pyrophosphoric acid, may enable efficient removal of resins having ether bonds. Furthermore, in particular, the inclusion of condensed phosphoric acid such as pyrophosphoric acid makes it easier to generate perphosphoric acid when hydrogen peroxide is subsequently mixed. As a result, it is believed that active oxygen species are more likely to be generated, which strengthens the effect of cleaving ether bonds and thereby improves the stripping effect.

[0021] The phosphoric acid in the stripper, solvent, or treatment solution may contain water, and the concentration of phosphoric acid may be any concentration that can strip and remove part or all of the resin having an ether bond from the substrate. The concentration of phosphoric acid in the stripper, solvent, or treatment solution can be appropriately adjusted taking into account the resin properties, such as the type, chemical resistance, amount, location, type of functional group, and glass transition temperature, of the resin contained in the semiconductor element, as well as the conditions of the treatment, such as stripping. From the viewpoint of the removal efficiency of the resin having an ether bond, the concentration of the phosphoric acid is preferably 0.1 wt% to 99.999 wt%, more preferably 10 wt% to 99.99 wt%, even more preferably 30 wt% to 99.99 wt%, and particularly preferably 40 wt% to 99.9 wt%. Furthermore, from the viewpoint of improving the removal efficiency of the resin having an ether bond, the concentration is preferably 80 wt% to 88 wt%, more preferably 82.5 wt% to 88.0 wt%, and even more preferably 83.0 wt% to 87.5 wt%. Within the above range, the resin having an ether bond can be efficiently removed.

[0022] When the pH of phosphoric acid can be measured, there are no particular limitations on the pH. However, in order to peel off and remove the resin having an ether bond, phosphoric acid acts as an acid, so a low pH of phosphoric acid is preferred.

[0023] The phosphoric acid may be produced by removing water from phosphoric acid. Examples of such a method include heating phosphoric acid to remove water; adding a dehydrating agent such as sulfuric acid or calcium chloride to phosphoric acid; or ２ O ５ Or P ４ O １０ Examples of such a method include adding phosphoric anhydride to phosphoric acid to cause hydrolysis. By adding these water removal operations, the concentration of phosphoric acid can be adjusted. These operations may be performed by a single operation or a combination of multiple operations. By combining multiple operations, the amount of water in phosphoric acid may be removed with good reproducibility.

[0024] The phosphoric acid contained in the stripping agent, solvent, or treatment liquid, or the ions generated by dissociation of phosphoric acid, is preferably phosphoric acid from which metal ions, organic impurities, particle particles, etc. have been removed by distillation, ion exchange treatment, filtration treatment, various adsorption treatments, various purification treatments, or the like.

[0025] The temperature at which the treatment using the stripping agent is performed may be any temperature at which part or all of the resin having an ether bond can be peeled and removed from the substrate, and can be appropriately adjusted taking into consideration the type of resin, chemical resistance, amount present, location present, type of functional group, resin characteristics, etc. When a peel-promoting catalyst described below is added, the preferred treatment temperature changes. However, when a stripping agent containing an aqueous phosphoric acid solution is used, the treatment temperature is preferably 20°C or higher and 400°C or lower, more preferably 80°C or higher and 400°C or lower, even more preferably 145°C or higher and 350°C or lower, and most preferably 145°C or higher and 250°C or lower, from the viewpoint of handling safety. Within the above range, the resin having an ether bond can be efficiently removed.

[0026] The inventors speculate that the reason why a stripper containing an aqueous phosphoric acid solution was effective against resins having ether bonds is that it is an acid that can be treated at high temperatures, as described above. Phosphoric acid itself is not a particularly strong acid, but at high temperatures, protons derived from high-concentration phosphoric acid act on ether bonds, cleaving the ether bonds, and oxygen atoms derived from the cleaved ether bond bond with phosphate groups derived from phosphoric acid. This decomposes the three-dimensional structure of the resins having ether bonds, and the resins having ether bonds are presumably dissolved and mixed in the phosphoric acid.

[0027] The treatment time using a stripping agent, solvent, or treatment liquid may be any time that allows for partial or complete stripping and removal of the resin having an ether bond from the substrate, and can be appropriately adjusted taking into consideration the type, chemical resistance, amount present, location present, type of functional group, or resin characteristics of the resin contained in the semiconductor element, as well as the type of stripping agent, solvent, or treatment liquid. From the viewpoint of the efficiency of removing the resin having an ether bond, the treatment time is preferably 0.1 minutes or more and 100 hours or less, more preferably 0.1 minutes or more and 50 hours or less, and even more preferably 0.1 minutes or more and 15 hours or less, and most preferably 0.1 minutes or more and 90 minutes or less from the viewpoint of economy. Within the above range, the resin having an ether bond can be efficiently removed.

[0028] The atmosphere in which the stripping agent, solvent, or treatment solution is used is not particularly limited, and may be air or an inert gas such as nitrogen or argon. The treatment may be carried out under normal pressure, reduced pressure, or increased pressure. From the viewpoint of safety during treatment, it is preferable to use the stripping agent, solvent, or treatment solution under normal pressure.

[0029] The treatment method with the stripping agent, solvent, or treatment liquid is not particularly limited, and the object may be immersed in the stripping agent, solvent, or treatment liquid, or the stripping agent may be sprayed onto the object using a single-wafer cleaning machine or a spray, etc. Furthermore, when treating at high temperatures, a cooler or the like may be attached during treatment, or the treatment may be performed under reflux in order to prevent volatilization of water, the stripping-promoting catalyst, etc.

[0030] (Strip-Promoting Catalyst) The stripping agent, solvent, or treatment liquid may contain a strip-promoting catalyst for the purpose of promoting the stripping and removal of the resin having an ether bond from the substrate. By containing these strip-promoting catalysts, the efficiency of stripping the target object from the substrate can be improved, and the time required for semiconductor manufacturing can be reduced. Furthermore, by containing these strip-promoting catalysts, the treatment temperature can be lowered, which is desirable from the viewpoint of safety in handling.

[0031] The stripping-promoting catalyst that can be contained in the stripper, solvent, or treatment liquid may be any catalyst that can act on ether bonds within resin molecules, hydrogen bonds and ether bonds between the resin and the substrate, or adhesive layers. This may be a metal catalyst or a non-metal catalyst. Among these, non-metal catalysts are preferred from the viewpoint of not containing metal atoms that are problematic in semiconductor manufacturing. Examples of such non-metal catalysts include at least one selected from the group consisting of acid catalysts and oxidizing agents. The use of such non-metal catalysts is preferred because they prevent corrosion of the Si substrate and are less likely to react with the phosphoric acid contained in the stripper, solvent, or treatment liquid. Furthermore, from the viewpoint of suppressing corrosion of the Si substrate, it is preferable that the stripper, solvent, or treatment liquid does not contain a basic component.

[0032] Examples of the acid catalyst include Lewis acids, inorganic acids, and organic acids. Examples of the non-metallic Lewis acids include BBr ３ bromides such as BF ３ , or PF ５ Examples of suitable non-metallic catalyst inorganic acids include at least one selected from the group consisting of hydrogen halides, sulfuric acid, nitric acid, and nitrous acid. Examples of suitable non-metallic catalyst organic acids include sulfonic acids such as methanesulfonic acid, p-toluenesulfonic acid, and trifluoromethanesulfonic acid, and carboxylic acids such as formic acid and acetic acid. Among these, at least one selected from the group consisting of hydrogen halides, sulfuric acid, nitric acid, nitrous acid, methanesulfonic acid, p-toluenesulfonic acid, and trifluoromethanesulfonic acid is preferred, and at least one selected from the group consisting of hydrogen halides, sulfuric acid, nitric acid, and nitrous acid is more preferred.

[0033] The oxidizing agent may be, for example, at least one selected from the group consisting of hydrogen peroxide, hydrohalic acid, halogen oxyacid, halogen, ozone, etc. Among these peel-promoting catalysts, at least one selected from the group consisting of hydrogen peroxide, hydrohalic acid, halogen oxyacid, and ozone is preferred because it has a strong effect of cleaving ether bonds, and hydrogen peroxide is more preferred. The inventors speculate that hydrogen peroxide functions as an oxidizing agent in the composition according to this embodiment.

[0034] Phosphoric acid forms complexes with various compounds and metals and induces hydrogen bonding. Therefore, it is expected to interact with these oxidizing agents and stabilize them. Phosphoric acid is known as a stabilizer for hydrogen peroxide, and is believed to be effective in extending the life of stripping agents, solvents, or treatment solutions. These stripping-promoting catalysts may also contain water.

[0035] (Concentration of peel-promoting catalyst) The concentration range of the peel-promoting catalyst may be any concentration range that can peel and remove part or all of the resin having an ether bond used from the substrate, and can be appropriately adjusted taking into consideration the type of peel-promoting catalyst used, the type, amount, location, type of functional group, peeling efficiency, handling safety, etc. of the resin contained in the semiconductor element. From the viewpoint of the removal efficiency of the resin having an ether bond, the concentration of the peel-promoting catalyst in the stripping agent, solvent, or treatment liquid is preferably 0.001 wt% or more and 50 wt% or less, more preferably 0.001 wt% or more and 30 wt% or less, and even more preferably 0.01 wt% or more and 20 wt% or less. From the viewpoint of economy and handling safety, 0.3 wt% or more and 15 wt% or less is most preferred. Within the above range, the resin having an ether bond can be efficiently removed.

[0036] When hydrogen peroxide is used as the stripping-promoting catalyst, the concentration range of hydrogen peroxide in the stripping agent, solvent, or treatment solution may be any concentration range that can strip and remove part or all of the resin having an ether bond used from the substrate, and can be appropriately adjusted taking into consideration the type, amount, location, and type of functional group of the resin contained in the semiconductor element, stripping efficiency, handling safety, etc. From the viewpoint of the removal efficiency of the resin having an ether bond, the concentration of hydrogen peroxide in the stripping agent, solvent, or treatment solution is preferably 0.001 wt % to 50 wt %, more preferably 0.01 wt % to 30 wt %, and even more preferably 0.1 wt % to 20 wt %. From the viewpoint of economy and handling safety, 0.3 wt % to 15 wt % is most preferred. Within the above range, the resin having an ether bond can be efficiently removed. When nitric acid is used as the stripping-promoting catalyst, the concentration range of nitric acid in the stripper, solvent, or treatment solution may be any concentration range that can strip and remove part or all of the resin having an ether bond used from the substrate, and can be appropriately adjusted taking into consideration the type, amount, location, type of functional group, stripping efficiency, handling safety, etc. of the resin contained in the semiconductor element. From the viewpoint of the removal efficiency of the resin having an ether bond, the concentration of nitric acid in the stripper, solvent, or treatment solution is preferably 0.001 wt% to 50 wt%, more preferably 0.01 wt% to 30 wt%, and even more preferably 0.1 wt% to 20 wt%, and from the viewpoint of economy and handling safety, most preferably 0.3 wt% to 15 wt%. Within the above range, the resin having an ether bond can be efficiently removed.

[0037] (Hydrogen Halide) The type of hydrogen halide that can be used as the peel-off promoting catalyst is not particularly limited, and examples thereof include hydrogen fluoride, hydrogen chloride, hydrogen bromide, hydrogen iodide, or ions thereof. Among these, hydrogen bromide is preferred because of its strong acidity, stability, and suitability for semiconductor applications.

[0038] (Hydrogen halide acid) The type of hydrohalogen acid that can be used as a peel-promoting catalyst is not particularly limited, and examples thereof include hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, etc. Among these, hydrobromic acid is preferred because of its strong acidity, stability, and suitability for semiconductor applications.

[0039] (Halogen Oxygen Acid) The type of halogen oxygen acid that can be used as a peeling-promoting catalyst is not particularly limited, and examples thereof include hypochlorous acid, chlorous acid, chloric acid, perchloric acid, hypobromous acid, bromous acid, bromic acid, perbromic acid, hypoiodous acid, iodous acid, iodic acid, metaperiodic acid, or orthoperiodic acid, or ions thereof.Among these, hypochlorous acid, perchloric acid, hypobromous acid, or orthoperiodic acid, or ions thereof, are preferred because of their oxidizing power, stability, and suitability for semiconductor applications, and orthoperiodic acid or orthoperiodic acid ions are most preferred.

[0040] (Halogen) The type of halogen that can be used as the peel-promoting catalyst is not particularly limited, and examples thereof include chlorine, bromine, iodine, etc. Among these, chlorine or bromine is preferred because of its oxidizing power, stability, and suitability for semiconductor applications.

[0041] (Ratio of peel-promoting catalyst to water) In a stripping agent, solvent, or treatment solution, the rate at which an object is peeled from a substrate can be stabilized by adjusting not only the concentration of the peel-promoting catalyst but also the ratio of the peel-promoting catalyst to water. For example, when the concentration of the peel-promoting catalyst is the same, temperature control can be difficult if the concentration of water is different. Therefore, adjusting the ratio of the peel-promoting catalyst to water makes it easier to control the temperature, and the rate at which an object is peeled from a substrate can be stabilized.

[0042] Furthermore, since water molecules are presumed to be involved in the reaction, controlling the amount of water makes it easier to control the reaction. Variations in the peeling speed can be suppressed and stabilized, improving the yield in semiconductor manufacturing. The ratio of the peel-promoting catalyst to water may be any ratio that can peel and remove part or all of the resin having an ether bond used from the substrate, and can be adjusted appropriately taking into account the type of peel-promoting catalyst used, the type, amount, location, and type of functional group of the resin contained in the semiconductor element, peeling efficiency, and handling safety, etc.

[0043] When the stripping agent, solvent, or treatment liquid contains water, from the viewpoint of the efficiency of removing a resin having an ether bond, the ratio of the stripping-promoting catalyst to water (stripping-promoting catalyst / water) is preferably from 0.00001 to 500,000 by weight, more preferably from 0.0001 to 100,000, even more preferably from 0.001 to 100,000, particularly preferably from 0.001 to 50,000, and from the viewpoint of economy and safety in handling, most preferably from 0.010 to 5,000. If the ratio is within the above range, the resin having an ether bond can be efficiently removed.

[0044] The water in the above ratio preferably refers to water derived from phosphoric acid, but when water is mixed in due to the addition of a stripping-promoting catalyst, the water derived from the stripping-promoting catalyst is also included, and it may also be water in the stripping agent, solvent, or treatment liquid. For example, when hydrogen bromide is used as the stripping-promoting catalyst, if the stripping agent, solvent, or treatment liquid is prepared using 47% hydrobromic acid, the water included in the 47% hydrobromic acid (if 47% hydrobromic acid consists only of hydrogen bromide and water, the water contained at 53%) is also included.

[0045] (Ratio of Hydrogen Peroxide to Water) When a stripper, solvent, or treatment solution contains water and hydrogen peroxide is used as a stripping-promoting catalyst, the ratio of hydrogen peroxide to water (hydrogen peroxide / water) in the stripper, solvent, or treatment solution may be any ratio that can strip and remove a portion or all of the resin having an ether bond used from the substrate. This ratio can be appropriately adjusted taking into consideration the type of stripping-promoting catalyst used, the type, amount, and location of the resin contained in the semiconductor element, the type of functional group, stripping efficiency, and handling safety. From the viewpoint of the removal efficiency of the resin having an ether bond, the ratio of hydrogen peroxide to water is preferably 0.00001 to 9.000 by weight, more preferably 0.0001 to 2.540, even more preferably 0.001 to 1.050, and particularly preferably 0.010 to 0.550. From the viewpoints of economy and handling safety, 0.10 to 0.400 is most preferred. When this ratio is within the above range, the resin having an ether bond can be efficiently removed. The water in the above ratio preferably refers to water derived from phosphoric acid, but may also include water derived from hydrogen peroxide when water is mixed in due to the addition of hydrogen peroxide, or may be water in the stripper, solvent, or treatment liquid. When hydrogen peroxide is used as the stripping-accelerating catalyst, for example, when a stripper, solvent, or treatment liquid is prepared using 30% hydrogen peroxide water, the water included in the 30% hydrogen peroxide water is also included.

[0046] (Ratio of nitric acid to water) When the stripping agent, solvent, or treatment solution contains water and nitric acid is used as the stripping-promoting catalyst, the ratio of nitric acid to water (nitric acid / water) in the stripping agent, solvent, or treatment solution may be any ratio that can strip and remove part or all of the resin having an ether bond used from the substrate. This can be appropriately adjusted taking into consideration the type of stripping-promoting catalyst used, the type, amount, location, and type of functional group of the resin contained in the semiconductor element, stripping efficiency, handling safety, etc. From the viewpoint of the removal efficiency of the resin having an ether bond, the ratio of nitric acid to water is preferably 0.0001 to 5.000 by weight, more preferably 0.001 to 2.500, and even more preferably 0.010 to 2.250. From the viewpoint of economy and handling safety, 0.200 to 1.500 is most preferred. When this ratio is within the above range, the resin having an ether bond can be efficiently removed. The water in the above ratio preferably refers to water derived from phosphoric acid, but may also include water derived from nitric acid when water is mixed in with the addition of nitric acid, or may be water in the stripper, solvent, or treatment liquid. When nitric acid is used as the stripping-promoting catalyst, for example, when a stripper, solvent, or treatment liquid is prepared using a 70% aqueous nitric acid solution, the water included in the 70% aqueous nitric acid solution is also included.

[0047] The method for adding the peel-promoting catalyst is not particularly limited and may be determined taking into consideration the type of catalyst used, etc. For example, the catalyst may be added by dissolving it in phosphoric acid or by dissolving phosphoric acid in a solution containing the catalyst. The method for dissolving the peel-promoting catalyst in phosphoric acid is not particularly limited and may be determined taking into consideration the properties of the catalyst, etc. The catalyst may be added to phosphoric acid and dissolved and mixed, or a solution containing the catalyst may be added to phosphoric acid and mixed. The method for dissolving phosphoric acid in a solution containing the catalyst is not particularly limited and may be determined taking into consideration the properties of the catalyst, etc. The phosphoric acid may be added to a solution containing the catalyst and dissolved and mixed, or a solution containing phosphoric acid may be added to a solution containing the catalyst and mixed. Furthermore, stirring, heating, etc. may be performed as needed. Furthermore, the peel-promoting catalyst only needs to be partially dissolved, and may exist in the form of a suspension or in a separated layer.

[0048] When hydrogen peroxide is used as the peel-accelerating catalyst, examples of the method of addition include adding and mixing liquid hydrogen peroxide directly with phosphoric acid, adding a solution containing hydrogen peroxide, such as aqueous hydrogen peroxide, to phosphoric acid, or adding phosphoric acid directly to hydrogen peroxide or aqueous hydrogen peroxide.

[0049] Examples of methods for adding hydrogen bromide when it is used as a stripping-promoting catalyst include a method of directly blowing hydrogen bromide gas into phosphoric acid, a method of adding a solution containing hydrogen bromide such as hydrobromic acid to phosphoric acid, or a method of adding a bromide salt such as sodium bromide to phosphoric acid. Examples of methods for adding nitric acid when nitric acid is used as a stripping-promoting catalyst include a method of directly adding and mixing liquid nitric acid with phosphoric acid, or a method of adding and mixing a solution containing nitric acid such as a nitric acid aqueous solution to phosphoric acid. Another method is to directly add phosphoric acid to nitric acid or a nitric acid aqueous solution.

[0050] When a peel-promoting catalyst is used, the temperature at which the treatment is performed using the stripping agent, solvent, or treatment solution may be any temperature at which part or all of the resin having an ether bond can be peeled and removed from the semiconductor substrate, and can be appropriately adjusted taking into consideration the type, chemical resistance, amount present, location of the resin, type of functional group, resin characteristics, and the type and amount of the peel-promoting catalyst added, etc., of the resin contained in the semiconductor element. From the viewpoint of the removal efficiency of the resin having an ether bond, the temperature at which the peeling treatment is performed is preferably 20°C or higher and 400°C or lower, more preferably 30°C or higher and 400°C or lower, and even more preferably 40°C or higher and 350°C or lower. From the viewpoint of handling safety, 50°C or higher and 250°C or lower are most preferred, and may be 80°C or higher and 250°C or lower. If the temperature is within the above range, the resin having an ether bond can be efficiently removed.

[0051] The stripping agent, solvent, or treatment liquid may contain one or more types of stripping-promoting catalysts. The inclusion of multiple types of catalysts may stabilize the speed at which the target object is stripped from the substrate.

[0052] (Activator) An activator that activates the peel-promoting catalyst may be added to the stripping agent, solvent, or treatment liquid. By adding the activator, the peel-promoting catalyst is activated, and the speed at which the object is peeled from the substrate may be increased. Furthermore, the reaction between the peel-promoting catalyst and the activator may generate new chemical species in the system, which may increase the speed at which the object is peeled from the substrate.

[0053] For example, when hydrogen peroxide is used as the peel-promoting catalyst, an activator such as an acid or a radical generator can be used. Examples of such acids include sulfuric acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, p-phenolsulfonic acid, benzenesulfonic acid, trifluoromethanesulfonic acid, nitric acid, nitrous acid, formic acid, acetic acid, propionic acid, butyric acid, benzoic acid, vanadic acid, tungstic acid, molybdic acid, chromic acid, osmium tetroxide, and selenium dioxide. Examples of radical generators include urea and amines.

[0054] The inclusion of these activators may cause the stripping agent, solvent, or treatment liquid to generate peracids, radicals, peroxides, or active oxygen species, which may increase the speed at which the target material is stripped from the substrate.

[0055] On the other hand, an example of an activator for hydrogen peroxide is the Fenton reagent. However, if this Fenton reagent remains on a semiconductor wafer, as described below, it can result in reduced yields of semiconductor elements. Examples of such Fenton reagents include iron ions, copper ions, and silver ions. For example, when nitric acid is used as the stripping-promoting catalyst, an activator such as an acid or hydrogen peroxide can be used. Examples of such acids include sulfuric acid, hydrobromic acid, acetic anhydride, trifluoroacetic acid, methanesulfonic acid, ethanesulfonic acid, o-toluenesulfonic acid, p-toluenesulfonic acid, p-phenolsulfonic acid, benzenesulfonic acid, m-nitrobenzenesulfonic acid, and trifluoromethanesulfonic acid. The inclusion of these activators can generate peracids, radicals, or nitrogen oxides in the stripping agent, solvent, or treatment solution, which can accelerate the rate at which the target material is stripped from the substrate.

[0056] (Water) The stripper, solvent, or treatment solution may contain water from the viewpoints of the stability of the stripping and removal speed of the resin having an ether bond from the substrate, handling safety, and the viscosity of the chemical solution. As described above, water may be contained in the stripper, solvent, or treatment solution as water contained in other components used as raw materials, or may be contained in the stripper, solvent, or treatment solution by adding only water. When water is contained by adding only water, water from which metal ions, organic impurities, particles, etc. have been removed by distillation, ion exchange treatment, filtration, various adsorption treatments, etc. is particularly preferred, and pure water or ultrapure water is particularly preferred. Such water can be obtained by known methods widely used in semiconductor manufacturing, etc.

[0057] When the stripping agent, solvent, or treatment liquid contains water, the concentration of water in the stripping agent, solvent, or treatment liquid is not particularly limited, but may be within a concentration range that can peel and remove part or all of the resin having an ether bond used from the substrate. This can be appropriately adjusted taking into consideration the type of peel-promoting catalyst used, the treatment temperature, the type, amount, and location of the resin contained in the semiconductor element, the type of functional group, peeling efficiency, and handling safety. From the viewpoint of the removal efficiency of the resin having an ether bond, the water concentration is preferably 0.5 wt% or more and 60.0 wt% or less, more preferably 1.0 wt% or more and 50.0 wt% or less, even more preferably 2.5 wt% or more and 50.0 wt% or less, and particularly preferably 4.0 wt% or more and 42.5 wt% or less. Within the above range, the resin having an ether bond can be efficiently removed.

[0058] If desired, other additives conventionally used in semiconductor processing solutions may be added to the stripper, solvent, or processing solution, provided that the purpose of the present invention is not impaired. For example, other additives may include metal corrosion inhibitors, organic solvents, catalysts, complexing agents, chelating agents, surfactants, antifoaming agents, pH adjusters, stabilizers, solubilizers, and precipitation inhibitors. These additives may be added alone or in combination.

[0059] (Stabilizer) A stabilizer may be added to the stripping agent, solvent, or treatment liquid in order to suppress decomposition of the stripping-accelerating catalyst. For example, examples of stabilizers when hydrogen peroxide is used as the stripping-accelerating catalyst include uric acid, barbituric acid, hippuric acid, cyanuric acid, amide compounds such as acetanilide, alkali metal carbonates, and alkali metal hydrogen carbonates.

[0060] The stripper, solvent, or treatment solution may contain a phosphoric acid analogue derived from phosphoric acid or for reasons of manufacturing convenience. Examples of such phosphoric acid analogues include phosphate esters, phosphines, phosphorous acids, phosphonic acids, hypophosphorous acids, and phosphinic acids. Examples of phosphate esters include phosphoric acid monoesters such as phenyl dihydrogen phosphate, benzyl dihydrogen phosphate, ethyl dihydrogen phosphate, and methyl dihydrogen phosphate; phosphoric acid diesters such as diphenyl phosphate, dibenzyl phosphate, diethyl phosphate, and dimethyl phosphate; and phosphoric acid triesters such as triphenyl phosphate, tribenzyl phosphate, triethyl phosphate, and trimethyl phosphate.

[0061] The stripping agent, solvent, or treatment liquid may contain alkali metal ions, alkaline earth metal ions, etc., derived from the stripping-promoting catalyst or additive, or for reasons of manufacturing the stripping agent, solvent, or treatment liquid. However, if these alkali metal ions and alkaline earth metal ions remain on the semiconductor wafer, they are likely to cause a decrease in the yield of semiconductor elements, etc.

[0062] Furthermore, the presence of metal ions such as chromium, manganese, iron, cobalt, copper, molybdenum, or tungsten in the stripping agent, solvent, or treatment liquid may cause decomposition of the stripping-promoting catalyst, etc. Therefore, the content of the metal in the stripping agent, solvent, or treatment liquid is preferably 1 ppb or less, more preferably 0.5 ppb or less, even more preferably 0.2 ppb or less, and most preferably 0.1 ppb or less, on a weight basis for each metal selected from lithium, sodium, potassium, aluminum, magnesium, calcium, chromium, manganese, iron, nickel, cobalt, copper, silver, cadmium, barium, tin, zinc, molybdenum, tungsten, and lead, and may be 0.01 ppt or more. Furthermore, among the above metals, the concentration of any one metal selected from iron, copper, manganese, chromium, and zinc is preferably 0.01 ppt to 1 ppb by weight, more preferably 0.01 ppt to 0.5 ppb, even more preferably 0.01 ppt to 0.2 ppb, and most preferably 0.01 ppt to 0.1 ppb. Furthermore, in the above explanation, ionic metals have been mentioned as metals that may be contained in the stripper, solvent, or treatment solution, but this is not limiting, and non-ionic metals (particulate metals) may also be contained, and the concentration thereof is preferably within the above range.

[0063] The stripping agent, solvent, or treatment liquid may contain gases such as hydrogen or oxygen due to the stripping-promoting catalyst or additive, or for reasons of manufacturing the stripping agent, solvent, or treatment liquid.

[0064] The stripping agent, solvent, or treatment liquid may contain active oxygen species, peracids such as perphosphoric acid, or nitrogen oxides derived from phosphoric acid, a stripping-promoting catalyst, or an activator, or for reasons of convenience in manufacturing the stripping agent, solvent, or treatment liquid. Examples of such active oxygen species include perhydroxy anion (O ２ H － ), or peroxide anion (.O ２ ２－ ), hydroxonium cation (OH ＋), perhydroxyl radical (.HO ２ ), hydroxyl radical (·OH), or superoxide anion radical (·O ２ － ) or singlet oxygen. Examples of such nitrogen oxides include nitrosonium ions (NO ＋ ), nitronium ion (NO ２ ＋ ), nitrate ions (NO ３ － ), nitrite ion (NO ２ － ), hyponitrite ion (NO － ), nitrogen dioxide (NO ２ ), nitrogen trioxide (N ２ O ３ ), dinitrogen tetroxide (N ２ O ４ ), or dinitrogen pentoxide (N ２ O ５ ) etc.

[0065] The inventors speculate that the reason why the stripping agent, solvent, or treatment solution was effective against resins having ether bonds is due to the active oxygen species, perphosphoric acid, or nitrogen oxides. These active oxygen species, perphosphoric acid, or nitrogen oxides act on the ether bonds of resins having ether bonds, cleaving the ether bonds and forming bonds between oxygen atoms derived from the cleaved ether and phosphate groups derived from the phosphoric acid. This decomposes the three-dimensional structure of the resins having ether bonds, leading to dissolution and miscibility in the phosphoric acid.

[0066] There are no particular limitations on the method for producing the stripping agent, solvent, or treatment liquid described above, and they can be prepared by blending the above-described components in desired amounts.

[0067] (Method for manufacturing semiconductor devices) The remover, solvent, or treatment liquid can be suitably used in a resin processing step, a resin stripping step, a resin removal step, a residue removal step, a cleaning step, or the like in the manufacture of semiconductors. The remover, solvent, or treatment liquid can also be used directly in the manufacture of semiconductor devices. The method for manufacturing semiconductor devices may include known steps used in the manufacture of semiconductor devices, such as one or more steps selected from a wafer fabrication step, an oxide film formation step, a transistor formation step, a wiring formation step, and a CMP step. In a method for manufacturing semiconductor devices according to an embodiment described below, a remover, solvent, or treatment liquid is used in a stripping step in which a resin having an ether bond is stripped from a semiconductor substrate. The above-mentioned processing step, resin removal step, residue removal step, cleaning step, or the like can be considered as one aspect of the stripping step.

[0068] (Reuse of Processing Liquid) After semiconductor devices are manufactured using a stripper, solvent, or processing liquid, the used liquid may be reused. Here, the used liquid refers to a stripper, solvent, or processing liquid that has been used at least once in a process such as a resin removal step during the manufacture of semiconductor wafers. Furthermore, when reusing the used liquid, the used liquid may be recycled, a new stripping-promoting catalyst may be added to the used liquid, or the phosphoric acid in the used liquid may be concentrated to reduce the water content before reuse.

[0069] (Object to be treated, substrate) The object to be treated with the stripping agent, solvent, or treatment solution is a resin having an ether bond attached to a substrate. The resin having an ether bond may be attached to the substrate via a chemical bond or a physical bond, or may be attached via an adhesive layer or the like. In addition, a part or all of the resin having an ether bond is the object to be treated. The material of the substrate is not particularly limited, and examples thereof include Si (silicon), Si compounds, ceramic, arsenic, phosphorus, metals, or metal compounds, and as a semiconductor substrate, Si or Si compounds are particularly preferred.

[0070] The Si compound is not particularly limited, and examples thereof include silicon oxide, silicon dioxide, glass silica, quartz, quartz, silicon carbide, silicon nitride, mica, clay, and calcium silicate. The metal is not particularly limited, and examples thereof include aluminum, gallium, chromium, cobalt, nickel, zinc, platinum, germanium, tantalum, and samarium. The metal compound is not particularly limited, and examples thereof include alumina, zirconia, ferrite, titania, magnesia, and aluminum hydroxide.

[0071] (Resin Having an Ether Bond) The resin having an ether bond is not particularly limited, but examples thereof include polyoxymethylene, polyphenylene ether, polyurethane resin, cyanate resin, phenol resin, cresol resin, xylenol resin, p-t-butylphenol resin, p-phenylphenol resin, resorcinol resin, epoxy resin, polyetherimide, polyethersulfone, polythioethersulfone, polyetherketone, polyetheretherketone, polyetherketone, polyallyletherketone, polyethernitrile, and ethyl cellulose. From the viewpoints of chemical resistance, moisture resistance, heat resistance, and suitability for use in semiconductor applications, polyurethane resin, phenol resin, cresol resin, epoxy resin, polyetherimide, and polyethersulfone are preferred, and from the viewpoints of chemical resistance, moisture resistance, heat resistance, and the like, epoxy resin or polyetherimide is most preferred.

[0072] Hereinafter, a specific description will be given of an example in which an epoxy resin is used as the resin having an ether bond.

[0073] (Epoxy Resin) Epoxy resins can be obtained by reacting pre-cured epoxy resins with their curing agents, and may also contain crosslinking agents, curing accelerators, catalysts, elastomers, or flame retardants. The pre-cured epoxy resin is not particularly limited, but examples include bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, bisphenol AD ​​epoxy resins, brominated bisphenol A epoxy resins, novolac glycidyl ethers, polyglycidyl ethers of polyhydric alcohols, polyglycidyl ethers of polybasic acids, and cresol novolac epoxy resins. Epoxy resins are excellent in terms of, for example, electrical properties, adhesiveness, and chemical resistance.

[0074] (Curing Agent) The curing agent is not particularly limited, and examples thereof include acid anhydrides, amine compounds, phenolic compounds, isocyanate compounds, organic phosphorus compounds, latent curing agents, cationic polymerization curing agents, anionic polymerization curing agents, and organic metal derivatives. Examples of acid anhydrides include phthalic anhydride, succinic anhydride, maleic anhydride, trimellitic anhydride, and nadic anhydride.

[0075] Examples of the amine compound include hexamethylenetetraamine, polyamidoamine, diaminodiphenylmethane, diaminodiphenylsulfone, and metaphenylenediamine. Examples of the phenol compound include hydroquinone, resoncinol, catechol, bisphenol A novolac, bisphenol F novolac, naphthalenediol, phenol aralkyl, biphenol novolac, and phenol novolac, as well as halides, alkyl group-substituted derivatives, and polycondensates thereof. Examples of the isocyanate compound include hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, diphenylmethane isocyanate, xylylene diisocyanate, and tolylene diisocyanate.

[0076] Examples of organic phosphorus compounds include hexamethylphosphoric triamide and triphenylphosphine. Examples of latent curing agents include dicyandiamide and ketimine. Examples of cationic polymerization curing agents include boron trifluoride-amine complexes. Examples of anionic polymerization curing agents include 2-ethyl-4-methylimidazole. Examples of metal organic derivatives include zinc naphthenate and zinc stearate. These curing agents may be used alone or in combination of two or more.

[0077] Examples of the curing accelerator include an imidazole compound, a tertiary amine compound, a quaternary ammonium salt, an organic phosphorus compound, etc. One type of curing accelerator may be used alone, or two or more types may be used in combination.

[0078] (Additives) The epoxy resin may contain various additives for the purpose of improving the resin properties of the epoxy resin. Examples of additives that can be used include inorganic fillers, emulsifiers, foaming agents, stabilizers, plasticizers, lubricants, flame retardant assistants, antistatic agents, colorants, chargeability imparting agents, and reactive diluents.

[0079] The inorganic filler is not particularly limited, and examples thereof include carbonates, sulfates, silicon compounds, titanate compounds, boron compounds, hydroxides, oxides, nitrides, and carbon-based fillers. Examples of carbonates include calcium carbonate and magnesium carbonate. Examples of sulfates include barium sulfate and calcium sulfate. Examples of silicon compounds include talc, mica, kaolin clay, wollastonite, sepiolite, hydrotalcite, montmorillonite, glass, silica, clay, and mica. Examples of titanate compounds include potassium titanate. Examples of boron compounds include aluminum borate. Examples of hydroxides include aluminum hydroxide, magnesium hydroxide, and calcium hydroxide. Examples of oxides include titanium oxide, zinc oxide, aluminum oxide, and magnesium oxide. Examples of nitrides include boron nitride and aluminum nitride. Examples of carbon-based fillers include carbon black, graphite, and carbon fiber.

[0080] The size of the resin having an ether bond to be treated is not particularly limited, and may be any size that can be treated in accordance with the scale of the treatment equipment and semiconductor element.

[0081] (Step of Peeling Off Resin Having an Ether Bond) A method for manufacturing a semiconductor device according to another embodiment of the present invention includes a step of performing a treatment (peeling treatment) to peel off a resin having an ether bond from a substrate (hereinafter referred to as the peeling step). This treatment refers to partially or completely peeling off a resin having an ether bond from a substrate using the above-mentioned peeling agent, solvent, or treatment liquid. These peeling steps include, for example, peeling off an adhesive layer between a substrate and a resin, or partially peeling off a resin from a resin layer. Furthermore, the substrate may be a semiconductor substrate.

[0082] (Speed ​​at which the object is peeled from the substrate) The speed at which the object is peeled from the substrate (hereinafter referred to as peeling speed) refers to the speed at which the above-mentioned peeling step is carried out and the resin having an ether bond attached to the substrate is partially or completely peeled from the substrate. From the viewpoint of the efficiency of removing the resin having an ether bond, a faster peeling speed is preferable. The peeling speed varies depending on the type of resin, chemical resistance, amount present, location present, type of functional group, resin characteristics, etc., but specifically, it is preferably 0.6 μm / min or more, and more preferably 2.1 μm / min or more. Furthermore, a peeling speed of 0.1 μm / min or less is not practical.

[0083] (Treatment for Swelling Resin Having Ether Bonds) In the peeling step, for the purpose of promoting peeling of the resin having an ether bond from the substrate, a treatment (hereinafter referred to as a swelling treatment) can be adopted as a pretreatment or intermediate treatment of the peeling treatment, in which the resin having an ether bond is immersed in a heated organic solvent to cause a volume change in the resin having an ether bond. By performing such a swelling treatment, it is possible to reduce the adhesive force between the resin having an ether bond and the substrate, thereby increasing the efficiency of peeling the resin having an ether bond from the substrate, reducing the time required for production, and enabling peeling from the substrate even under milder conditions.

[0084] As the organic solvent used in the swelling treatment, a polar solvent such as water may be contained in the release agent used in the peeling treatment after the swelling treatment, so it is preferable to use a polar solvent. These polar solvents may contain water, and the solvent may be one type or multiple types. Examples of polar solvents include polar solvents such as alcohols, ketones, nitriles, ethers, esters, carboxylic acids, sulfur-containing compounds, and nitrogen-containing compounds. Examples of polar alcohol solvents include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 1-hexanol, 2-hexanol, 3-hexanol, 2-methyl-1-pentanol, 1-heptanol, 2-heptanol, 3-heptanol, dodecanol, cyclohexanol, 1-methylcyclohexanol, phenol, m-cresol, benzyl alcohol, phenoxyethanol, salicylic alcohol, anisyl alcohol, anise alcohol, phenethyl alcohol, 2-methylphenethyl alcohol, 4-methylphenethyl alcohol, 2-methylbenzyl alcohol, 4-methylbenzyl alcohol, 2-ethoxybenzoic acid ... Examples of polar solvents include ethylbenzyl alcohol, 4-ethylbenzyl alcohol, 2-methoxyphenethyl alcohol, 4-methoxybenzyl alcohol, 4-ethoxybenzyl alcohol, vanillyl alcohol, veratryl alcohol, cinnamyl alcohol, benzhydrol, trityl alcohol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,5-pentanediol, and glycerin. Examples of polar solvents for ketones include acetone. Examples of polar solvents for nitriles include acetonitrile and propanenitrile.

[0085] Examples of polar solvents for ethers include tetrahydrofuran, etc. Examples of polar solvents for esters include methyl acetate, ethyl acetate, or propylene carbonate, etc. Examples of polar solvents for carboxylic acids include formic acid or acetic acid, etc. Examples of polar solvents for sulfur-containing compounds include dimethyl sulfoxide, dimethyl sulfone, or sulfolane, etc.

[0086] Examples of polar solvents for nitrogen-containing compounds include N,N,N',N'-tetramethylurea, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylformamide, N-methylacetamide, N-methyl-2-pyrrolidone, acetamide, nitromethane, etc. Among these solvents, 1-pentanol, 1-hexanol, phenol, cresol, benzyl alcohol, salicyl alcohol, anisyl alcohol, anise alcohol, phenethyl alcohol, vanillyl alcohol, veratryl alcohol, cinnamyl alcohol, benzhydrol, trityl alcohol, ethylene glycol, propylene glycol, diethylene glycol, butanediol, glycerin, dimethyl sulfoxide, dimethyl sulfone, sulfolane, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone are preferred because they have high boiling points and can be used to perform swelling treatment at high temperatures.

[0087] Furthermore, from the viewpoint of easy availability of low-cost, high-purity products, phenol, cresol, benzyl alcohol, anise alcohol, ethylene glycol, propylene glycol, glycerin, dimethyl sulfoxide, sulfolane, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone are more preferred. Furthermore, from the viewpoint of easy availability of high-purity products for semiconductors, benzyl alcohol, ethylene glycol, glycerin, dimethyl sulfoxide, and N-methyl-2-pyrrolidone are even more preferred. Furthermore, dimethyl sulfoxide is most preferred because it promotes peeling of resins having ether bonds from substrates.

[0088] The temperature of the swelling treatment, if included, may be any temperature capable of reducing the adhesive strength between the resin having an ether bond and the substrate, and can be appropriately adjusted taking into consideration the type, chemical resistance, amount present, location present, and type of functional group of the resin contained in the semiconductor element, as well as resin properties such as the resin's glass transition temperature, and the type of organic solvent. From the viewpoint of the efficiency of removing the resin having an ether bond, this temperature is preferably 20°C or higher and 400°C or lower, more preferably 20°C or higher and 300°C or lower, and even more preferably 50°C or higher and 250°C or lower, and most preferably 50°C or higher and 200°C or lower from the viewpoint of handling safety. If the temperature is within the above range, the adhesive strength between the resin having an ether bond and the substrate can be reduced, and the resin having an ether bond can be efficiently removed in the subsequent peeling step.

[0089] The present invention will be explained in more detail below with reference to experimental examples, but the present invention is not limited to these experimental examples.

[0090] (Substrate containing resin having ether bond) An epoxy resin composition was prepared using a bisphenol A type epoxy resin ("jER (registered trademark) 1001" manufactured by Mitsubishi Chemical Corporation) as the resin having an ether bond, a phenol compound ("jER Cure (registered trademark) 170" manufactured by Mitsubishi Chemical Corporation) as the curing agent, and imidazole as the curing accelerator. The compounding ratio of the epoxy resin to the curing agent was adjusted so that the epoxy equivalent / hydroxyl group equivalent was 1. Next, a silicon wafer was impregnated with the obtained epoxy resin composition and cured in a dryer at 150°C for 30 minutes, to obtain a substrate containing an epoxy resin with a resin thickness of about 0.5 to 1.0 mm. The obtained substrates were each cut into 10 mm x 20 mm to prepare test pieces.

[0091] (Evaluation of peeling rate by release agent) The test piece obtained as described above was immersed in a release agent for a predetermined time, and the peeling rate before and after was evaluated by the following method. The epoxy resin on the Si substrate was observed using a digital microscope (Keyence Corporation, VHX-8000), and the difference in thickness of the epoxy resin before and after immersion in the release agent was calculated to evaluate the amount of peeling. This amount of peeling was divided by the treatment time to evaluate the peeling rate [μm / min].

[0092] (Evaluation of the amount of dissolution in solvent) The test piece obtained as described above was immersed in a solvent for a predetermined time, and the amount of resin dissolved before and after was evaluated by the following method. Using a laser microscope (Keyence Corporation, VK-9710), the volume of the epoxy resin on the Si substrate was measured, and the rate of volume reduction before and after immersion in the solvent was calculated and evaluated according to the following criteria. In all cases, ratings A to C were acceptable levels, and rating D was unacceptable.

[0093] A: Completely dissolved (100% reduction) B: 50% or more reduction C: 10% or more but less than 50% reduction D: Reduction rate less than 10%

[0094] (Evaluation of Smoothness of Si Substrate by Treatment Solution) The test pieces obtained as described above were immersed in the treatment solution for a predetermined time, and the smoothness of the Si substrate was evaluated as follows. The surface of the Si substrate was observed using a field emission scanning electron microscope (JSM-7800F Prime, manufactured by JEOL Ltd.) to check for the presence or absence of surface roughness, and evaluated according to the following criteria. Evaluation A was an acceptable level, and evaluations B and C were unacceptable levels.

[0095] A: No surface roughness is observed. B: Surface roughness is observed. C: Surface roughness is observed, and there is a change in the surface area of ​​the Si substrate compared to before immersion. Note that a small change in the Si substrate indicates little corrosion of the Si.

[0096] (Preparation of Release Agent, Semiconductor Device Manufacturing Method) <Experimental Examples A1 to A4> A rotor (manufactured by AsOne, total length 30 mm x diameter 8 mm) was placed in a three-necked flask, a thermometer protection tube (manufactured by Cosmos Bead, bottom-sealed type) and a thermometer were placed in one opening, a PFA tube (manufactured by Flon Industries Co., Ltd., F-8011-02) connected to a nitrogen gas cylinder was connected to the other opening, and a Dimroth condenser (manufactured by AsOne, model number 4-421-04) was connected to the remaining opening. Phosphoric acid (85 wt%, manufactured by Fujifilm Wako Co., Ltd.) was added to the three-necked flask, and a release agent for a resin having an ether bond (semiconductor release agent) was obtained. The prepared release agent was heated to the temperature shown in Table 1, and then the test piece was placed in a three-neck flask and immersed for 30 minutes. The vessel was then allowed to cool naturally to 100°C, after which the test piece was removed and the release rate of the resin was evaluated by the method described above in the section (Evaluation of release rate by release agent), and the results are shown in Table 1.

[0097] Experimental Examples A5 to A18: As in Experimental Examples A1 to A4, phosphoric acid (85 wt %, Fujifilm Wako Corporation) was added to a three-neck flask. Hydrogen peroxide (30 wt %, Fujifilm Wako Corporation) was then added to obtain the composition shown in Table 1, yielding a release agent for a resin having an ether bond (semiconductor release agent). The prepared release agent was heated to the temperature shown in Table 1, and the test piece was placed in the three-neck flask. The release agent was immersed for the time shown in Table 1. The container was then allowed to cool naturally to 100°C, after which the test piece was removed. In Experimental Examples A13 to A14, the test piece was removed without cooling the container. The release rate of the resin was then evaluated using the method described above in the section (Evaluation of Release Rate by Release Agent), and the results are shown in Table 1.

[0098] Experimental Examples A19 to A29 In Experimental Examples A19 to A21, treatment with a release agent (semiconductor release agent) was carried out under the conditions shown in Table 2 in the same manner as Experimental Example A5, except that a release-promoting catalyst having the composition shown in Table 2 was used. The release rates of the resins were evaluated using the method described above in the section (Evaluation of release rate by release agent), and the results are shown in Table 2. In Experimental Example A19, orthoperiodic acid (98.5 wt % orthoperiodic acid, manufactured by FUJIFILM Wako Co., Ltd.) was used as the release-promoting catalyst, in Experimental Example A20, hydrogen bromide (47 wt % hydrobromic acid, manufactured by FUJIFILM Wako Co., Ltd.) was used as the release-promoting catalyst, and in Experimental Examples A21 to A29, nitric acid (70 wt % nitric acid, manufactured by FUJIFILM Wako Co., Ltd.) was used as the release-promoting catalyst.

[0099] Experimental Examples B1 to B8 In Experimental Examples B1 to B8, treatment with a stripper (semiconductor stripper) was carried out under the conditions shown in Table 3 in the same manner as Experimental Examples A5 to A18, except that the stripper did not contain phosphoric acid and the composition shown in Table 3 was used. The stripping rate of the resin was evaluated by the method described above in the section (Evaluation of Stripping Rate by Stripper), and the results are shown in Table 3. In Experimental Example B2, 37 wt % hydrochloric acid (manufactured by Fujifilm Wako Co., Ltd.) was used as HCl, in Experimental Example B3, 48 wt % aqueous sodium hydroxide solution (manufactured by Hayashi Pure Chemical Industries Co., Ltd.) was used as NaOH, and in Experimental Example B4, 37 wt % aqueous sodium hydroxide solution (manufactured by Hayashi Pure Chemical Industries Co., Ltd.) was used as NaOH. ２ O ２ In Experimental Example B1, 30 wt% hydrogen peroxide solution (manufactured by Fujifilm Wako Corporation) was used, in Experimental Example B5, 30 wt% hydrogen peroxide solution (manufactured by Fujifilm Wako Corporation) and N-methylpyrrolidone (manufactured by Fujifilm Wako Corporation) were used, in Experimental Example B6, 30 wt% hydrogen peroxide solution (manufactured by Fujifilm Wako Corporation) and 98 wt% sulfuric acid (manufactured by Fujifilm Wako Corporation) were used, in Experimental Example B7, benzyl alcohol (manufactured by Fujifilm Wako Corporation) and potassium phosphate (manufactured by Fujifilm Wako Corporation) were used, and in Experimental Example B8, potassium hydroxide (manufactured by Fujifilm Wako Corporation) and N-methylpyrrolidone (manufactured by Fujifilm Wako Corporation) were used.

[0100] In each experimental example, each raw material contains water, which acts as a solvent. When no other solvents are used, water is the only solvent. The type of solvent and its concentration in the stripper are shown in the following tables. When a component other than water is used as a solvent, this component is treated as the solvent, and its type and concentration are shown in each table.

[0101]

[0102]

[0103]

[0104] It can be seen from Tables 1 to 3 that the stripping agents of Experimental Examples A1 to A29 can perform stripping at a faster rate than the stripping agents of Experimental Examples B1 to B8.

[0105] <Experimental Examples A30 to A47, B9 to B11> In the same manner as in Experimental Examples A5 to A29, treatment with a solvent (semiconductor solvent) was carried out under the conditions shown in Table 4, and the amount of resin dissolved was evaluated by the method described above in the section (Evaluation of the amount dissolved by the solvent), and the results are shown in Table 4.

[0106]

[0107] <Experimental Examples A48 to A65, B12 to B14> In the same manner as in Experimental Examples A5 to A29, treatment was performed using a treatment liquid (semiconductor treatment liquid) under the conditions shown in Table 5, and the smoothness of the Si substrate was evaluated by the method described above in (Evaluation of smoothness of Si substrate using treatment liquid), and the results are shown in Table 5.

[0108]

[0109] Experimental Examples A7, A66 to A86: A rotor (manufactured by AsOne, total length 30 mm x diameter 8 mm) was placed in a three-neck flask, a thermometer protection tube (manufactured by Cosmos Bead, bottom-sealed type) and a thermometer were placed in one opening, a PFA tube (manufactured by Flon Industries Co., Ltd., F-8011-02) connected to a nitrogen gas cylinder was connected to the other opening, and a PFA tube (manufactured by Flon Industries Co., Ltd., F-8011-02) connected to an Erlenmeyer flask was connected to the remaining opening. Phosphoric acid (85 wt%, manufactured by Fujifilm Wako Co., Ltd.) was added to the three-neck flask, heated to 180 ° C, and maintained at 180 ° C for 30 minutes. The phosphoric acid was then cooled to 100 ° C to obtain 99.0 wt% phosphoric acid. Water was then added to achieve the initial phosphoric acid concentration shown in Table 6. Thereafter, treatment with a stripping agent (semiconductor stripping agent) was carried out under the conditions shown in Table 6 in the same manner as in Experimental Examples A5 to A18, except that a 30% aqueous solution of hydrogen peroxide was added to prepare a stripping agent having the composition shown in Table 6. The stripping rate of the resin was evaluated by the method described above in (Evaluation of stripping rate by stripping agent), and the results are shown in Table 6.

[0110]

[0111] Experimental Examples A21, A87 to A93: 97.0 wt % phosphoric acid was obtained in the same manner as Experimental Examples A66 to A86. Then, 70% nitric acid was added to prepare a stripper having the composition shown in Table 7. In the same manner as Experimental Examples A66 to A86, treatment with a stripper (semiconductor stripper) was carried out under the conditions shown in Table 7, and the stripping rate of the resin was evaluated by the method described above in the section (Evaluation of stripping rate by stripper), and the results are shown in Table 7.

[0112]

[0113] Experimental Examples A7 and A94: As in Experimental Examples A5 to A18, phosphoric acid (85 wt %, Fujifilm Wako Co., Ltd.) was added to a three-neck flask. Hydrogen peroxide solution (30 wt %, Fujifilm Wako Co., Ltd.) was then added to the flask to a concentration of 3 wt %. Pyrophosphoric acid (Fujifilm Wako Co., Ltd.) was then added to the flask to a concentration of 6 wt %, yielding a release agent for a resin having an ether bond (semiconductor release agent). The prepared release agent was heated to 145°C, and the test piece was placed in the three-neck flask and immersed for 30 minutes. The container was allowed to cool naturally to near room temperature, after which the test piece was removed. The release rate of the resin was evaluated using the method described above in the section (Evaluation of Release Rate by Release Agent), resulting in a value of 11.0 μm / min. The initial phosphoric acid concentration in Table 8 represents the concentration of the phosphoric acid product used.

[0114]

Claims

1. A semiconductor stripping agent used to strip a resin having an ether bond from a semiconductor substrate, wherein the stripping agent contains phosphoric acid, and the concentration of the phosphoric acid is 80% by weight or more and 88% by weight or less.

2. The semiconductor release agent according to claim 1, wherein the resin having the ether bond is an epoxy resin.

3. A release agent used to remove a resin having an ether bond from a substrate, comprising water, phosphoric acid, and a release-promoting catalyst.

4. The stripping agent according to claim 3, wherein the ratio of the stripping-promoting catalyst to the water is 0.0001 or more and 100.000 or less by weight.

5. The stripping agent according to claim 3 or 4, wherein the phosphoric acid comprises pyrophosphate.

6. The stripping agent according to claim 3 or 4, wherein the stripping-promoting catalyst is at least one selected from the group consisting of oxidizing agents and acid catalysts.

7. The stripping agent according to claim 6, wherein the oxidizing agent is at least one selected from the group consisting of hydrogen peroxide, halogen oxygen acid, hydrohalic acid, halogen, and ozone.

8. The stripping agent according to claim 6, wherein the acid catalyst is at least one selected from the group consisting of hydrogen halides, sulfuric acid, nitric acid, and nitrite.

9. The release agent according to claim 3 or 4, wherein the resin having the ether bond is an epoxy resin.

10. The stripping agent according to claim 6, wherein the oxidizing agent is hydrogen peroxide, and the ratio of hydrogen peroxide to water is 0.010 or more and 0.550 or less by weight.

11. The stripping agent according to claim 3, which is a stripping agent for semiconductors.

12. A semiconductor solvent used to dissolve a resin having an ether bond and to peel it off from a semiconductor substrate, comprising phosphoric acid and a peel-promoting catalyst.

13. A semiconductor processing solution used to peel off a resin having ether bonds from a semiconductor substrate, comprising phosphoric acid and a peel-promoting catalyst.

14. A method for manufacturing a semiconductor device, comprising a peeling step of peeling a resin having ether bonds from a semiconductor substrate using the peeling agent described in claim 11, the semiconductor solvent described in claim 12, or the semiconductor processing solution described in claim 13.

15. A method for manufacturing a semiconductor device, comprising a peeling step of peeling a resin having ether bonds from a semiconductor substrate using the peeling agent described in claim 11, the semiconductor solvent described in claim 12, or the semiconductor processing liquid described in claim 13, wherein the processing is performed at a temperature of 20°C or higher and 400°C or lower.