Method for manufacturing semiconductor substrate

Abstract

In one embodiment, provided is a method for manufacturing a semiconductor substrate, capable of suppressing generation of fine temporary fixing agent residue.　In one embodiment, the present disclosure relates to a method for manufacturing a semiconductor substrate, including the following steps 1 and 2. Step 1: Preparing a semiconductor substrate to which a film-form temporary fixing agent is bonded. Step 2: Peeling the film-form temporary fixing agent from the semiconductor substrate obtained in step 1 with a cleaning agent containing a glycol ether, a hydrocarbon, and an amine

Description

Semiconductor substrate manufacturing method

[0001] The present disclosure relates to a method for manufacturing a semiconductor substrate.

[0002] In recent years, the high integration of semiconductor devices has progressed dramatically, and three-dimensional integrated circuit (3DIC) technology has attracted attention. 3DIC technology is a technique for stacking substrates in multiple layers while connecting them using through-silicon vias (TSVs) and other methods. When stacking substrates in multiple layers, the backside of the substrate (the side without the circuit) on which the circuit is formed must be thinned by polishing, and further processing such as forming electrodes on the backside is required. Before thinning, the substrate is temporarily fixed (temporarily adhered) to a fixing member (support) with a temporary fixing agent (adhesive). After processing such as polishing and electrode formation, the substrate is separated from the fixing member. After the substrate is separated from the fixing member, the temporary fixing agent (adhesive) often remains, which can cause problems in subsequent processes. Therefore, various peeling and cleaning methods have been developed to reduce the amount of temporary fixing agent (adhesive) remaining on the substrate.

[0003] For example, Japanese Patent Laid-Open No. 2010-28063 (Patent Document 1) proposes a sheet peeling method in which an adhesive sheet is peeled from an adherend by relative movement between an adherend having an adhesive sheet attached to its surface and a peeling tape attached to the adhesive sheet. Japanese Patent No. 7121355 (Patent Document 2) proposes a method for producing a processed semiconductor substrate, including a first step of producing a laminate comprising a semiconductor substrate, a support substrate, and an adhesive layer obtained from an adhesive composition, a second step of processing the semiconductor substrate of the obtained laminate, a third step of peeling the semiconductor substrate after processing, and a fourth step of cleaning and removing adhesive residue remaining on the peeled semiconductor substrate with a specific cleaning composition.

[0004] In one aspect, the present disclosure relates to a method for manufacturing a semiconductor substrate, including the following steps 1 and 2: Step 1: preparing a semiconductor substrate to which a film-like temporary fixing agent is adhered; and Step 2: peeling the film-like temporary fixing agent from the semiconductor substrate obtained in Step 1 using a cleaning agent containing a glycol ether, a hydrocarbon, and an amine.

[0005] In one aspect, the present disclosure relates to a method for removing a film-like temporary fixing agent without performing a peeling treatment, the method including a step of washing a semiconductor substrate to which a film-like temporary fixing agent is adhered with a cleaning agent, and peeling off the film-like temporary fixing agent.

[0006] In the manufacturing process of three-dimensional integrated circuits (3DICs), processing such as electrode formation after polishing a substrate temporarily fixed (temporarily bonded) to a fixing member (support) with a temporary fixing agent (adhesive) can be performed at high temperatures of 150°C or higher. If the temporary fixing agent (adhesive) is altered by heating, the temporary fixing agent residue (adhesive residue) remaining on the semiconductor substrate after the fixing member is separated is difficult to remove. When a film-type temporary fixing agent (adhesive sheet) is used as the temporary fixing agent, the film-type temporary fixing agent (adhesive sheet) is typically peeled, as proposed in Patent Document 1. Here, peeling of the film-type temporary fixing agent refers to peeling off the film (temporary fixing agent) while holding the edge of the film. However, peeling the film-type temporary fixing agent (adhesive sheet) can sometimes leave small pieces of temporary fixing agent residue (adhesive residue) on the substrate. This is particularly likely to occur when bumps are present on the substrate. Such small pieces of temporary fixing agent residue (adhesive residue) are even more difficult to remove.

[0007] Therefore, the present disclosure provides a method for manufacturing a semiconductor substrate that can suppress the generation of fragmented temporary fixing agent residue.

[0008] According to the present disclosure, it is possible to provide a method for manufacturing a semiconductor substrate that can suppress the generation of fragmented temporary fixing agent residue.

[0009] The present disclosure is based on the finding that by treating a semiconductor substrate to which a film-like temporary fixing agent is adhered with a specific cleaning agent without peeling the film-like temporary fixing agent, the film-like temporary fixing agent can be peeled off (removed) and the generation of fragmented temporary fixing agent residue can be suppressed.

[0010] In one aspect, the present disclosure relates to a method for manufacturing a semiconductor substrate (hereinafter also referred to as the "semiconductor substrate manufacturing method of the present disclosure"), which includes the following steps 1 and 2: Step 1: preparing a semiconductor substrate to which a film-like temporary fixing agent is adhered; and Step 2: peeling the film-like temporary fixing agent from the semiconductor substrate obtained in Step 1 using a cleaning agent containing a glycol ether, a hydrocarbon, and an amine.

[0011] According to the present disclosure, it is possible to provide a method for manufacturing a semiconductor substrate that can suppress the generation of fragmented temporary fixing agent residue, and to obtain high-quality semiconductor substrates with a high yield.

[0012] Although the details of the mechanism by which the effects of the present disclosure manifest are unclear, it is presumed as follows. The temporary fixative hardens when subjected to a heat treatment, and a portion of the temporary fixative adheres more strongly to the bump surface. Therefore, when a film-like temporary fixative is subjected to a peeling treatment, the temporary fixative strongly adsorbed to the bump surface is likely to break apart and remain on the bump as small pieces of temporary fixative residue. Generally, cleaning agents can swell the temporary fixative and generate stress. However, in the case of such small pieces of temporary fixative residue, the stress generated by the swelling escapes to the surrounding area, making it impossible to peel. Therefore, in the present disclosure, the film-like temporary fixative can be entirely swelled by a cleaning agent containing glycol ether, hydrocarbon, and amine without a peeling treatment of the film-like temporary fixative. Therefore, it is believed that the film-like temporary fixative can be removed (peeled) without leaving small pieces of temporary fixative residue. However, the present disclosure need not be interpreted as being limited to this mechanism.

[0013] Examples of the semiconductor substrate include substrates (wafers) such as silicon substrates (wafers), silicon carbide substrates (wafers), germanium substrates (wafers), gallium nitride substrates (wafers), gallium-arsenic substrates (wafers), gallium-phosphorus substrates (wafers), and gallium-arsenic-aluminum substrates (wafers). In one or more embodiments, the semiconductor substrate may be a substrate (wafer) having pads and / or lands that are sites for bonding and mounting. In one or more embodiments, the semiconductor substrate may be a substrate (wafer) having bumps.

[0014] Examples of temporary fixing agents (adhesives) include those that can bond (temporarily fix, adhere) a semiconductor substrate to a fixing member, have durability that can withstand polishing and processing, and allow the semiconductor substrate to be easily separated from the fixing member. Examples of temporary fixing agents (adhesives) include polyimide-based, polysiloxane-based, acrylic-based, and methacrylic-based temporary fixing agents (adhesives). Examples of film-like temporary fixing agents include adhesive sheets (sheets, films, tapes, etc.). In one or more embodiments, the film-like temporary fixing agent is one that is conventionally removed by a peeling process, and in one or more embodiments, is suitable for a peeling process. Examples of the thickness of the temporary fixing agent (adhesive) include 5 μm or more and 500 μm or less, preferably 10 μm or more and 100 μm or less.

[0015] In one or more embodiments, the semiconductor substrate manufacturing method of the present disclosure does not include a step of peeling the film-like temporary fixing agent (peeling step) between step 1 and step 2. In one or more embodiments, the peeling step is a step of peeling the temporary fixing agent by peeling the semiconductor substrate to which the film-like temporary fixing agent is adhered. In one or more embodiments, peeling the film-like temporary fixing agent in the present disclosure refers to peeling the film (temporary fixing agent) while holding the edge of the film of the temporary fixing agent.

[0016] [Step 1: Preparation] Step 1 in the semiconductor substrate manufacturing method of the present disclosure is a step of preparing a semiconductor substrate to which a film-like temporary fixing agent is adhered. In one or more embodiments, Step 1 includes the following adhesion step (a), polishing step (b), processing step (c), and separation step (d): (a) an adhesion step of adhering a substrate to a fixing member with a film-like temporary fixing agent (adhesive sheet); (b) a polishing step of polishing the surface of the substrate opposite to the surface adhered to the fixing member; (c) a processing step of processing the polished surface of the substrate; and (d) a separation step of separating the fixing member from a laminate of the fixing member, the film-like temporary fixing agent (adhesive sheet), and the substrate. Each of the above steps is described below.

[0017] <Step (a): Bonding Step> Step (a) is a step (bonding step) of bonding a substrate to a fixing member with a film-like temporary fixing agent (adhesive sheet). In one or more embodiments, step (a) includes bonding the substrate and the fixing member together via the film-like temporary fixing agent (adhesive sheet), and then heat-treating the laminate of the substrate, the film-like temporary fixing agent (adhesive sheet), and the fixing member to bond them together. Examples of the substrate used in step (a) include silicon substrates (wafers) and glass substrates (wafers) having a diameter of 100 to 500 mm and a thickness of 500 to 2000 μm. Examples of the fixing member used in step (a) include, but are not limited to, silicon substrates (wafers) and glass plates having a diameter of 100 to 500 mm and a thickness of 500 to 20,000 μm. The film-like temporary fixing agent (adhesive sheet) used in step (a) is not particularly limited as long as it can bond the substrate to the fixing member, has durability sufficient to withstand the polishing and processing steps, and allows the substrate to be easily separated from the fixing member in the separation step. Examples of such temporary fixing agents include film-like temporary fixing agents (adhesive sheets) used in the manufacturing process of 3DICs. Examples of adhesive components of the film-like temporary fixing agent (adhesive sheet) used in the manufacturing process of 3DICs include polyimide-based, polysiloxane-based, acrylic-based, and methacrylic adhesives. Specific examples include the adhesives described in JP 2021-161196 A. In one or more embodiments, the film-like temporary fixing agent (adhesive sheet) used in step (a) may include an adhesive component containing polysiloxane, an acrylic acid ester, or a methacrylic acid ester, and may further contain a platinum group metal catalyst, a release agent component, and the like. The film-like temporary fixing agent (adhesive sheet) may have a thickness of, for example, 5 to 500 μm. The temperature for the heat treatment after bonding the substrate and the fixing member via the film-like temporary fixing agent (adhesive sheet) is, for example, 80°C or higher, and is preferably 150°C or lower from the viewpoint of preventing excessive hardening of the temporary fixing agent (adhesive). The time for the heat treatment is, for example, 30 seconds or longer, and is preferably 10 minutes or shorter from the viewpoint of preventing deterioration of the film-like temporary fixing agent (adhesive sheet) and other members. Heating can be performed using a hot plate, an oven, or the like.The film thickness of the film-like temporary fixing agent (adhesive sheet) after the heat treatment is, for example, 5 μm or more and 500 μm or less.

[0018] <Step (b): Polishing Step> Step (b) is a polishing step in which the back surface of the substrate opposite to the adhesive surface to be bonded to the fixing member (the surface opposite to the adhesive surface) is polished. Examples of the polishing method include mechanical polishing using abrasive grains and chemical mechanical polishing. In step (b), the thickness of the substrate (thinned substrate) after polishing is preferably 200 μm or less, and examples thereof include 50 μm to 200 μm.

[0019] <Step (c): Processing Step> Step (c) is a step (processing step) of processing the polished surface of the substrate (the back surface of the thinned substrate). In one or more embodiments, examples of step (c) include an electrode formation step, a metal wiring formation step, a protective film formation step, and the like. Examples include conventionally known processing steps such as metal sputtering for forming electrodes, wet etching, resist application, pattern formation, resist stripping, dry etching, metal plating, silicon etching for forming through-silicon vias (TSVs), and oxide film formation on silicon surfaces. In one or more embodiments, the processing in step (c) is performed at a high temperature of 150°C or higher. When forming electrodes such as TSVs, a heat treatment at, for example, 250°C to 350°C may be performed. The film thickness of the film-like temporary fixing agent (adhesive sheet) after the heat treatment at high temperature may be, for example, 5 μm to 500 μm.

[0020] <Step (d): Separation Step> Step (d) is a separation step in which the fixing member is separated from the laminate of the fixing member, the film-like temporary fixing agent (adhesive sheet), and the substrate. Examples of the separation method include solvent peeling, laser peeling, mechanical peeling, etc. In one or more embodiments, the substrate from which the fixing member has been separated is a substrate to which the film-like temporary fixing agent (adhesive) has been adhered.

[0021] [Step 2: Cleaning] Step 2 in the semiconductor substrate manufacturing method of the present disclosure is a step (hereinafter also referred to as a "cleaning step") in which a semiconductor substrate (hereinafter also referred to as an "object to be cleaned") to which a film-like temporary fixing agent is adhered is cleaned with a cleaner containing glycol ether, hydrocarbon, and amine to peel the film-like temporary fixing agent from the semiconductor substrate (object to be cleaned). This cleaning step does not include a peeling process. Examples of peeling processes include mechanical peeling. In the present disclosure, "peeling" refers to removing the temporary fixing agent from the object to be cleaned while at least a portion of the temporary fixing agent is swollen and retaining its film-like shape. In one or more embodiments, "removing" includes washing away. Therefore, in one or more embodiments, Step 2 includes swelling the film-like temporary fixing agent with the cleaner and washing away the temporary fixing agent from the semiconductor substrate. In one or more embodiments, the peeling in Step 2 may include dissolving a portion of the film-like temporary fixing agent with the cleaner, but does not include dissolving the entire film-like temporary fixing agent. In one or more embodiments, the step 2 is a step of peeling off the film-like temporary fixing agent before 50% or more, 30% or more, 20% or more, or 10% or more of the film-like temporary fixing agent is dissolved by the cleaner.

[0022] Examples of the cleaning method in step 2 include immersion cleaning and spray cleaning. The temperature of the cleaning agent is preferably, for example, 40°C or higher and 120°C or lower. The immersion time in immersion cleaning is preferably, for example, 1 minute or higher and 60 minutes or lower. Ultrasonic vibration may be applied during immersion in the cleaning agent, and examples of ultrasonic conditions include 25 to 50 kHz or 35 to 45 kHz. The spray time in spray cleaning is preferably, for example, 1 minute or higher and 60 minutes or lower.

[0023] (Cleaning Agent) In one or more embodiments, the cleaning agent used in step 2 contains a glycol ether, a hydrocarbon, and an amine.

[0024] <Glycol Ether> Examples of glycol ethers include those containing a compound represented by the following formula (I). The glycol ether may be one type or a combination of two or more types. The content of the compound represented by the following formula (I) in the glycol ether is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 100% by mass. R-O-(AO) ｎ-H (I) In the above formula (I), R represents a hydrocarbon group having from 1 to 6 carbon atoms, AO represents an ethyleneoxy group (EO) or a propyleneoxy group (PO), and n represents the number of moles of AO added, which is a number of from 1 to 3. In the above formula (I), from the viewpoint of improving the removability of the adhesive, R is preferably a phenyl group or an alkyl group having from 1 to 6 carbon atoms, more preferably an alkyl group having from 1 to 6 carbon atoms, and even more preferably an alkyl group having from 1 to 4 carbon atoms. From the same viewpoint, AO is preferably an ethyleneoxy group (EO). From the same viewpoint, n is preferably from 1 to 3. Examples of the compound represented by the above formula (I) include monophenyl ethers such as ethylene glycol monophenyl ether, diethylene glycol monophenyl ether, and triethylene glycol monophenyl ether; monoalkyl ethers having an alkyl group having from 1 to 6 carbon atoms, such as ethylene glycol monoalkyl ether, diethylene glycol monoalkyl ether, triethylene glycol monoalkyl ether, and tripropylene glycol monoalkyl ether; and the like. Among these, from the viewpoint of improving adhesive removability, the compound represented by formula (I) is preferably at least one selected from ethylene glycol monoalkyl ether, diethylene glycol monoalkyl ether, triethylene glycol monoalkyl ether, and tripropylene glycol monoalkyl ether, each having an alkyl group having from 1 to 6 carbon atoms, and even more preferably at least one selected from ethylene glycol monobutyl ether, diethylene glycol monobutyl ether (BDG), and propylene glycol monomethyl ether (PGME). In one or more embodiments, the glycol ether has a solubility in water at 20°C of greater than 10% by mass. From the viewpoint of improving adhesive removability, the glycol ether is preferably a diethylene glycol monoalkyl ether having an alkyl group having from 1 to 6 carbon atoms, and more preferably diethylene glycol monobutyl ether (BDG).When the cleaning agent contains glycol ether, the content of glycol ether in the cleaning agent is preferably 10% by mass or more, more preferably 15% by mass or more, from the viewpoints of improving adhesive removability and compatibility, and is preferably 65% ​​by mass or less, more preferably 60% by mass or less, from the viewpoint of improving adhesive removability. More specifically, the content of glycol ether in the cleaning agent is, for example, 10% by mass or more and 65% by mass or less, or 15% by mass or more and 60% by mass or less. When two or more glycol ethers are used in combination, the content of glycol ether refers to the total content of the glycol ethers.

[0025] <Hydrocarbons> In one or more embodiments, the hydrocarbon is a hydrocarbon-based organic solvent. From the viewpoint of improving adhesive removability, hydrocarbons having a cyclic structure are preferred, and organic solvents such as alicyclic hydrocarbons and aromatic hydrocarbons are more preferred. Examples of alicyclic hydrocarbons include cycloalkanes such as cyclohexane. Examples of aromatic hydrocarbons include toluene, ethylbenzene, xylene, and mesitylene (1,3,5-trimethylbenzene). The hydrocarbon may be a single type or a combination of two or more types. The total content of alicyclic hydrocarbons and aromatic hydrocarbons in the hydrocarbon is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 100% by mass. From the viewpoint of improving adhesive removability, the number of carbon atoms in the hydrocarbon is preferably 5 or more, more preferably 6 or more, and from the same viewpoint, preferably 14 or less, more preferably 12 or less, even more preferably 10 or less, and even more preferably 9 or less. When the hydrocarbon is an alicyclic hydrocarbon, from the same viewpoint, the number of carbon atoms in the alicyclic hydrocarbon is preferably 5 or more, and preferably 14 or less, more preferably 10 or less, and even more preferably 8 or less. When the hydrocarbon is an aromatic hydrocarbon, from the same viewpoint, the number of carbon atoms in the aromatic hydrocarbon is preferably 5 or more, more preferably 6 or more, and even more preferably 7 or more, and preferably 14 or less, more preferably 12 or less, more preferably 10 or less, and even more preferably 9 or less. Examples of hydrocarbons include at least one selected from ethylbenzene, xylene, mesitylene, and cyclohexane, and from the viewpoints of improving adhesive removability, storage stability, availability, and chemical substance regulations, ethylbenzene or xylene is preferred. Examples of hydrocarbons include at least one selected from alicyclic hydrocarbons and aromatic hydrocarbons. From the viewpoint of improving the removability of the adhesive, aromatic hydrocarbons are preferred, aromatic hydrocarbons having 5 to 14 carbon atoms are more preferred, aromatic hydrocarbons having 6 to 12 carbon atoms are even more preferred, aromatic hydrocarbons having 7 to 10 carbon atoms are even more preferred, aromatic hydrocarbons having 7 to 9 carbon atoms are even more preferred, at least one selected from ethylenebenzene, xylene, and methylenebenzene is even more preferred, and ethylbenzene is even more preferred.The content of hydrocarbons in the cleaning agent is preferably 10% by mass or more, more preferably 15% by mass or more, and 25% by mass or more from the viewpoint of improving adhesive removability, and is preferably 90% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less from the viewpoint of compatibility. More specifically, the content of hydrocarbons in the cleaning agent is preferably 10% by mass or more and 80% by mass or less, or 10% by mass or more and 90% by mass or less, or 15% by mass or more and 90% by mass or less, or 25% by mass or more and 80% by mass or less, or 25% by mass or more and 75% by mass or less. When two or more hydrocarbons are used in combination, the content of hydrocarbons refers to the total content of those hydrocarbons.

[0026] <Amine> Examples of amines include alkanolamines (amino alcohols). Examples of alkanolamines (amino alcohols) include those containing a compound represented by the following formula (II). The amine may be one type or a combination of two or more types. In one or more embodiments, the alkanolamine is a compound that does not have a branched carbon chain. The content of the compound represented by the following formula (II) in the alkanolamine is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 100% by mass. In the above formula (II), R １ represents a linear alkanol group having 2 to 4 carbon atoms, and R ２ represents a linear alkanol group having 2 to 4 carbon atoms, a methyl group, or a hydrogen atom; R ３ represents a methyl group or a hydrogen atom. １ From the viewpoint of improving the removability of the adhesive, R is preferably a linear alkanol group having 2 or 3 carbon atoms. ２ From the same viewpoint, R is preferably a hydrogen atom. ３is preferably a hydrogen atom from the same viewpoint. Examples of amines include at least one selected from monoethanolamine, N-methylmonoethanolamine, N-ethylmonoethanolamine, diethanolamine, N-dimethylmonoethanolamine, N-methyldiethanolamine, N-diethylmonoethanolamine, N-ethyldiethanolamine, N-(β-aminoethyl)ethanolamine, and N-(β-aminoethyl)diethanolamine. Among these, from the viewpoint of improving adhesive removability, alkylmonoalkanolamines or monoalkanolamines are preferred, and monoethanolamine is more preferred. From the viewpoint of improving adhesive removability, the content of the amine in the cleaning agent is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more. From the viewpoints of improving adhesive removability, preventing damage to components, and reducing the nitrogen content, the content is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less. More specifically, the amine content in the cleaning agent is preferably, for example, 3% by mass to 50% by mass, 5% by mass to 45% by mass, or 8% by mass to 40% by mass. When two or more amines are used in combination, the amine content refers to the total content of the amines.

[0027] <Mass Ratio (Amine / Glycol Ether)> From the viewpoint of improving adhesive removability, the mass ratio of amine to glycol ether (amine / glycol ether) in the cleaning agent is preferably 0.01 or more, more preferably 0.05 or more, even more preferably 0.1 or more, and from the same viewpoint, it is preferably 10 or less, more preferably 5 or less, and even more preferably 2 or less. <Mass Ratio (Amine / Hydrocarbon)> From the viewpoint of improving adhesive removability, the mass ratio of amine to hydrocarbon (amine / hydrocarbon) in the pre-cleaning agent is preferably 0.01 or more, more preferably 0.05 or more, and even more preferably 0.1 or more, and from the same viewpoint, it is preferably 10 or less, more preferably 5 or less, and even more preferably 1 or less. <Mass Ratio (Glycol Ether / Hydrocarbon)> From the viewpoint of improving adhesive removability, the mass ratio of glycol ether to hydrocarbon (glycol ether / hydrocarbon) in the pre-cleaning agent is preferably 0.01 or more, more preferably 0.1 or more, and even more preferably 0.2 or more, and from the same viewpoint, it is preferably 10 or less, more preferably 5 or less, and even more preferably 1 or less.

[0028] <Other Components> In one or more embodiments, the cleaning agent may further contain water and other components as needed. Examples of other components include components that can be used in ordinary cleaning agents, such as solvents other than organic solvents, alkali agents other than amines, surfactants, chelating agents, thickeners, dispersants, rust inhibitors, polymer compounds, solubilizers, antioxidants, preservatives, antifoaming agents, and antibacterial agents.

[0029] In the present disclosure, the "content of each component in the cleaning agent" refers to the content of each component at the time of cleaning, i.e., at the time when the cleaning agent starts to be used for cleaning. In one or more embodiments, the cleaning agent can be produced by blending an organic solvent and / or an amine, and, as needed, the above-mentioned optional components (water and other components) using a known method.

[0030] After cleaning in step 2, the substrate may be rinsed with water or alcohol (rinse liquid) and then dried. Examples of alcohol include at least one selected from methanol, ethanol, isopropyl alcohol, and propylene glycol monomethyl ether. Examples of the temperature of the rinse liquid include 10°C to 60°C. Examples of the rinse time include 10 seconds to 300 seconds. Here, the rinse time refers to the time during which the rinse liquid is supplied. The rinse treatment method is not particularly limited, and methods commonly used for cleaning substrates in semiconductor substrate manufacturing processes can be employed. Examples include a method of immersing the substrate in a rinse liquid, a method of pouring the rinse liquid onto the substrate, and a method of supplying the rinse liquid to the substrate while spinning the substrate. The drying method is not particularly limited, and examples include static drying. Static drying can be performed at room temperature (e.g., 25°C).

[0031] [Object to be Cleaned] Examples of objects to be cleaned include semiconductor substrates to which a film-like temporary fixing agent (adhesive sheet) is adhered. Examples of semiconductor substrates include substrates (wafers) such as silicon substrates (wafers), silicon carbide substrates (wafers), germanium substrates (wafers), gallium nitride substrates (wafers), gallium-arsenic substrates (wafers), gallium-phosphorus substrates (wafers), and gallium-arsenic-aluminum substrates (wafers). In one or more embodiments, examples of the substrate (wafer) include substrates (wafers) having pads and / or lands that serve as bonding and mounting sites. Examples of materials for the pads and lands include metals such as gold and copper. In one or more embodiments, the semiconductor substrate includes substrates (wafers) having bumps. Examples of the bumps include ball bumps and plated bumps. Examples of the bump size include a bump height of 1 to 200 μm, a bump diameter of 1 to 200 μm, and a bump pitch of 1 to 500 μm. In one or more embodiments, examples of the semiconductor substrate to which a film-like temporary fixing agent (adhesive sheet) is adhered include a semiconductor substrate to which a film-like temporary fixing agent (adhesive sheet) is adhered, a semiconductor substrate to which a film-like temporary fixing agent (adhesive sheet) has not been subjected to a peeling treatment, a semiconductor substrate after a substrate temporarily fixed (adhered) to a fixing member with a film-like temporary fixing agent (adhesive sheet) has been separated from the fixing member, and a substrate after the fixing member has been separated from a laminate of a fixing member and a substrate adhered via a film-like temporary fixing agent (adhesive sheet). In one or more embodiments, examples of the semiconductor substrate to which a film-like temporary fixing agent (adhesive sheet) is adhered include a semiconductor substrate to which a film-like temporary fixing agent (adhesive sheet) used in the manufacturing process of a three-dimensional integrated circuit (3DIC) is adhered. In one or more embodiments, the semiconductor substrate to which a film-like temporary fixing agent (adhesive sheet) is adhered has undergone a heat treatment at a temperature of 230°C or higher. In one or more embodiments, the heat treatment can be the heat treatment in the processing step described above.

[0032] [Method for Removing a Film-Like Temporary Fixing Agent] In one aspect, the present disclosure relates to a method for removing a film-like temporary fixing agent without a peeling treatment, the method including a step (cleaning step) of cleaning a semiconductor substrate (object to be cleaned) to which a film-like temporary fixing agent (adhesive sheet) is adhered with a cleaning agent, thereby peeling off the film-like temporary fixing agent (hereinafter also referred to as the "removing method of the present disclosure"). Examples of objects to be cleaned in the removing method of the present disclosure include the objects described above. Examples of cleaning agents in the removing method of the present disclosure include the cleaning agent used in step 2 of the semiconductor substrate manufacturing method of the present disclosure. Examples of cleaning methods for the cleaning step in the removing method of the present disclosure include the same method as the cleaning method in step 2 of the semiconductor substrate manufacturing method of the present disclosure. In one or more embodiments, the removing method of the present disclosure can suppress the generation of shredded temporary fixing agent residue.

[0033] The present disclosure further relates to one or more of the following embodiments. <1> A method for manufacturing a semiconductor substrate, including the following steps 1 and 2: Step 1: preparing a semiconductor substrate to which a film-like temporary fixing agent is adhered; and Step 2: peeling the film-like temporary fixing agent from the semiconductor substrate obtained in step 1 using a cleaning agent containing a glycol ether, a hydrocarbon, and an amine. <2> The manufacturing method according to <1>, in which the thickness of the temporary fixing agent is 5 μm or more and 500 μm or less. <3> The manufacturing method according to <1> or <2>, in which the thickness of the temporary fixing agent is 10 μm or more and 100 μm or less. <4> The manufacturing method according to any one of <1> to <3>, in which the glycol ether is a compound represented by the following formula (I): R-O-(AO) ｎ-H (I) In the above formula (I), R represents a hydrocarbon group having 1 to 6 carbon atoms, AO represents an ethyleneoxy group (EO) or a propyleneoxy group (PO), and n represents the number of moles of AO added, which is a number of 1 to 3. <5> The production method according to any one of <1> to <4>, wherein the hydrocarbon is at least one selected from ethylbenzene, xylene, mesitylene, and cyclohexane. <6> The production method according to any one of <1> to <5>, wherein the hydrocarbon has 5 or more or 6 or more carbon atoms and 14 or less, 12 or less, 10 or less, or 9 or less carbon atoms. <7> The production method according to any one of <1> to <6>, wherein the amine contains a compound represented by the following formula (II): In the above formula (II), R １ represents a linear alkanol group having 2 to 4 carbon atoms, and R ２ represents a linear alkanol group having 2 to 4 carbon atoms, a methyl group, or a hydrogen atom; R ３represents a methyl group or a hydrogen atom. <8> The production method according to any one of <1> to <7>, wherein the mass ratio of amine to glycol ether (amine / glycol ether) in the cleaning agent used in step 2 is 0.01 or more and 10 or less. <9> The production method according to any one of <1> to <8>, wherein the mass ratio of amine to glycol ether (amine / glycol ether) in the cleaning agent used in step 2 is 0.01 or more, or 0.05 or more, or 0.1 or more, and 10 or less, or 5 or less, or 2 or less. <10> The production method according to any one of <1> to <9>, wherein the mass ratio of amine to hydrocarbon (amine / hydrocarbon) in the cleaning agent used in step 2 is 0.01 or more and 10 or less. <11> The method according to any one of <1> to <10>, wherein the mass ratio of amine to hydrocarbon (amine / hydrocarbon) in the cleaning agent used in step 2 is 0.01 or more, or 0.05 or more, or 0.1 or more, and 10 or less, or 5 or less, or 1 or less. <12> The method according to any one of <1> to <11>, wherein the mass ratio of glycol ether to hydrocarbon (glycol ether / hydrocarbon) in the cleaning agent used in step 2 is 0.01 or more, or 0.1 or more, or 0.2 or more, and 10 or less, or 5 or less, or 1 or less. <13> The method according to any one of <1> to <12>, wherein the content of glycol ether in the cleaning agent used in step 2 is 10% by mass or more and 65% by mass or less, or 15% by mass or more and 60% by mass or less. <14> The production method according to any one of <1> to <13>, wherein the content of hydrocarbons in the cleaning agent used in step 2 is 10% by mass or more and 80% by mass or less, or 10% by mass or more and 90% by mass or less, or 15% by mass or more and 90% by mass or less, or 25% by mass or more and 80% by mass or less, or 25% by mass or more and 75% by mass or less. <15> The production method according to any one of <1> to <14>, wherein the content of amines in the cleaning agent used in step 2 is 3% by mass or more and 50% by mass or less, or 5% by mass or more and 45% by mass or less, or 8% by mass or more and 40% by mass or less.<16> The manufacturing method according to any one of <1> to <15>, wherein the temporary fixing agent is at least one selected from polyimide-based, polysiloxane-based, acrylic-based, and methacrylic-based agents. <17> The manufacturing method according to any one of <1> to <16>, wherein step 1 includes the following bonding step (a), polishing step (b), processing step (c), and separation step (d): (a) a bonding step of bonding a substrate wafer to a fixing member with a film-like temporary fixing agent, (b) a polishing step of polishing the backside of the surface of the substrate wafer bonded to the fixing member, (c) a processing step of processing the polished surface of the substrate wafer, and (d) a separation step of separating the fixing member from the laminate of the fixing member, the film-like temporary fixing agent, and the substrate wafer. <18> The manufacturing method according to any one of <1> to <17>, wherein step 2 includes swelling the film-like temporary fixing agent with the cleaning agent and washing away the temporary fixing agent from the semiconductor substrate wafer. <19> A method for removing a film-like temporary fixing agent without performing a peeling treatment, the method comprising the step of cleaning a semiconductor substrate wafer to which a film-like temporary fixing agent is adhered with a cleaning agent, and peeling off the film-like temporary fixing agent.

[0034] The present disclosure will be specifically described below using examples, but the present disclosure is not limited to these examples in any way.

[0035] 1. Preparation of Detergents The components shown in Table 1 were blended in the amounts (% by mass, active ingredient) shown in Table 1, and the mixture was stirred and mixed to prepare detergents.

[0036] The following substances were used to prepare the cleaning agent: MEA: monoethanolamine [manufactured by Nippon Shokubai Co., Ltd.] BDG: butyl diglycol [manufactured by Nippon Nyukazai Co., Ltd., diethylene glycol monobutyl ether] Ethylbenzene [manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.]

[0037]

[0038] 2. Evaluation of Cleanability (Removability of Film-Like Temporary Fixing Agent) (Example 1, Comparative Example 1) The following cleaning test was performed using the following test pieces, and the appearance was evaluated. [Test Piece] The test pieces were 40 mm x 40 mm in size. The test pieces were prepared by coating a 5 μm-thick layer of polybenzoxazole in the gaps between the bumps of a silicon wafer (thickness: 700 μm) having bumps (height: 50 μm, diameter: 60 μm, pitch: 100 μm). A film-like temporary fixing agent (thickness: 50 μm, adhesive component: acrylic) was then applied to the entire upper surface of the wafer, followed by heat treatment at high temperature (290°C) for 30 minutes. The thickness of the film-like temporary fixing agent after the heat treatment at high temperature was 50 μm. In Example 1, the test pieces were used in the cleaning test without subjecting the film-like temporary fixing agent to a peeling treatment. In Comparative Example 1, the test pieces were used in the cleaning test after subjecting the film-like temporary fixing agent to a peeling treatment. The peeling treatment was performed by pinching the edge of the film-like temporary fixing agent with tweezers and peeling it off (mechanical peeling). [Cleaning Test] 3 kg of each cleaning composition was added to a 5-L stainless steel beaker. The mixture was heated to 60°C, and the test pieces were sprayed for 30 minutes while circulating using a box-type spray washer equipped with a one-fluid nozzle (full cone-shaped) J020 (manufactured by Ikeuchi Co., Ltd.) (pressure: 0.1 MPa, spray distance: 8 cm). After rinsing with ethanol (25°C) for 20 seconds, the test pieces were allowed to dry at room temperature (25°C). The test pieces after the treatment were visually observed at 1500x magnification using a scanning electron microscope (SEM, manufactured by JEOL Ltd.) to evaluate the cleanability. The results are shown in Table 2. <Surface Cleanliness Evaluation Criteria> A: 1 μm on the bump surface ２ B: No residue less than 1 μm is found on the bump surface ２ 3 μm or more ２ C: Residue less than 3 μm is observed on the bump surface ２ More than 5 μm ２ Residue less than 5 μm is observed on the bump surface. ２The above residues were observed. Note that in the cleaning test of Example 1, it was visually observed that the temporary fixing agent on the test piece was peeled off and washed away. The temporary fixing agent on the test piece of Comparative Example 1 was roughly peeled off by the peeling treatment, so in the cleaning test of Comparative Example 1, it was not possible to visually confirm that the temporary fixing agent was washed away, but a large amount of temporary fixing agent residue remained on the bump surfaces after cleaning.

[0039]

[0040] As shown in Table 2, in Example 1, in which the film-like temporary fixing agent was treated with a cleaning agent without being subjected to a peeling treatment, no shredded residue of the temporary fixing agent was found on the wafer surface after cleaning, whereas in Comparative Example 1, in which the film-like temporary fixing agent was treated with a cleaning agent after being subjected to a peeling treatment, shredded residue of the temporary fixing agent was found on the wafer surface after cleaning. Therefore, it was found that treating the film-like temporary fixing agent with a cleaning agent without peeling it can prevent the generation of shredded residue of the temporary fixing agent on the substrate surface after cleaning.

[0041] According to the present disclosure, it is possible to provide a method for manufacturing a semiconductor substrate that can suppress the generation of fragmented temporary fixing agent residue, thereby improving the productivity of semiconductor substrates.

Claims

1. A method for manufacturing a semiconductor substrate, comprising the following steps 1 and 2: Step 1: preparing a semiconductor substrate to which a film-like temporary fixing agent is adhered; and Step 2: peeling the film-like temporary fixing agent from the semiconductor substrate obtained in Step 1 using a cleaning agent containing glycol ether, hydrocarbon, and amine.

2. The manufacturing method according to claim 1, wherein the thickness of the temporary fixing agent is 5 μm or more and 500 μm or less.

3. The manufacturing method according to claim 1 or 2, wherein the thickness of the temporary fixing agent is 10 μm or more and 100 μm or less.

4. The method of any one of claims 1 to 3, wherein the mass ratio of amine to glycol ether (amine / glycol ether) in the cleaning agent used in step 2 is 0.01 or more and 10 or less.

5. The method of any one of claims 1 to 4, wherein the mass ratio of amine to hydrocarbon (amine / hydrocarbon) in the cleaning agent used in step 2 is 0.01 or more and 10 or less.

6. A manufacturing method described in any one of claims 1 to 5, wherein the content of glycol ether in the cleaning agent used in step 2 is 10% by mass or more and 65% by mass or less.

7. A manufacturing method according to any one of claims 1 to 6, wherein the hydrocarbon content in the cleaning agent used in step 2 is 10% by mass or more and 90% by mass or less.

8. A manufacturing method described in any one of claims 1 to 7, wherein the amine content in the cleaning agent used in step 2 is 3% by mass or more and 50% by mass or less.

9. The manufacturing method according to any one of claims 1 to 8, wherein the temporary fixing agent is at least one selected from the group consisting of polyimides, polysiloxanes, acrylics, and methacrylics.

10. A manufacturing method according to any one of claims 1 to 9, wherein step 1 includes the following steps: bonding step (a), polishing step (b), processing step (c), and separation step (d). (a) a bonding step of bonding a substrate to a fixing member with a film-like temporary fixing agent; (b) a polishing step of polishing the surface of the substrate opposite to the surface bonded to the fixing member; (c) a processing step of processing the polished surface of the substrate; and (d) a separation step of separating the fixing member from the laminate of the fixing member, the film-like temporary fixing agent, and the substrate.

11. A manufacturing method according to any one of claims 1 to 10, wherein step 2 includes swelling the film-like temporary fixing agent with the cleaning agent and washing the temporary fixing agent away from the semiconductor substrate.

12. A method for removing a film-like temporary fixing agent without performing a peeling process, comprising the step of washing a semiconductor substrate to which a film-like temporary fixing agent is adhered with a cleaning agent, and peeling off the film-like temporary fixing agent.

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