TW201800529A - Adhesive film for processing semiconductor wafer - Google Patents

Abstract

An adhesive film (100) for processing a semiconductor wafer is provided. The adhesive film (100) sequentially includes a base layer (10), an antistatic layer (30) and an adhesive resin layer (40), and is adapted to protect a surface of the semiconductor wafer or to fix the semiconductor wafer. Besides, the adhesive resin layer (40) includes an ion-conductive additive.

Description

Adhesive film for semiconductor wafer processing

The present invention relates to an adhesive film for processing semiconductor wafers.

In the manufacturing step of the semiconductor device, in the step of grinding or cutting the semiconductor wafer, the adhesive film is attached to the semiconductor wafer in order to fix the semiconductor wafer or prevent damage of the semiconductor wafer. Such an adhesive film is generally used for a film in which an ultraviolet curable adhesive resin layer is laminated on a base film. Since the adhesive film is irradiated with ultraviolet rays, the adhesive resin layer is crosslinked and the adhesive force of the adhesive resin layer is lowered, so that the adhesive film can be easily peeled off from the semiconductor wafer.

On the other hand, in the manufacturing process of the semiconductor device using such an adhesive film, there is a case where static electricity called peeling static electricity is generated when the adhesive film is peeled off from the semiconductor wafer. The static electricity generated in this way causes the circuit formed on the semiconductor wafer to be broken (electrostatic breakdown) or foreign matter such as dust to adhere to the circuit formed on the semiconductor wafer. In particular, with the recent increase in density of semiconductor wafers and narrow pitch of wiring, semiconductor wafers tend to be more susceptible to static electricity than hitherto. In view of the above, in recent years, an adhesive film used for fixing a semiconductor wafer or preventing damage of a semiconductor wafer in a manufacturing step of a semiconductor device is also required to further improve antistatic performance.

As a technique related to such an adhesive film for semiconductor wafer processing, for example, it is described in Patent Document 1 (Japanese Laid-Open Patent Publication No. 2011-210944).

Patent Document 1 discloses an adhesive tape for processing an antistatic semiconductor, which is an adhesive tape including a base film and a photocurable adhesive layer, and the adhesive tape for antistatic semiconductor processing is characterized by An antistatic layer containing a conductive polymer is provided on at least one surface of the base film, and an adhesive layer containing a photocurable unsaturated carbon bond in the molecule of the base polymer is provided on the antistatic layer, and the ultraviolet curing is performed. The front surface of the adhesive layer side has a surface resistivity of 1×10 ⁶ Ω/□ to 5×10 ¹² Ω/□, and the adhesive layer has a thickness of 20 μm to 250 μm, and the adhesive tape is attached to the 矽 mirror surface crystal. 90 degree peel adhesion after UV curing of the adhesive layer at round (according to Japanese Industrial Standards (JIS) Z 0237; peeling speed 50 mm/min) 0.15 N/25 mm to 0.25 N/25 Mm. [Prior Art Document] [Patent Literature]

Patent Document 1: Japanese Patent Laid-Open Publication No. 2011-210944

[Problems to be Solved by the Invention] As described in the related art, in recent years, the technical level required for the viewpoint of the countermeasure against static electricity of the adhesive film for semiconductor wafer processing has been gradually improved. According to the study by the inventors of the present invention, it has been clarified that the adhesive film in which the base film, the antistatic layer, and the adhesive layer are sequentially laminated as described in Patent Document 1 does not sufficiently satisfy the antistatic property. More specifically, it is clear that the adhesive film described in Patent Document 1 has a large increase in the saturated electrostatic voltage of the adhesive layer after ultraviolet curing, and the antistatic property is seriously deteriorated.

In view of the above, the present invention provides an adhesive film for processing a semiconductor wafer, which is excellent in antistatic property after ultraviolet curing, and can suppress the amount of static electricity generated when peeling from a semiconductor wafer, and can stably Get high quality semiconductor parts.

[Means for Solving the Problems] The inventors of the present invention have repeatedly conducted efforts to achieve the above problems. As a result, it has been found that by adding an ion conductive additive to the adhesive resin layer to the adhesive film including the base material layer, the antistatic layer, and the adhesive resin layer in this order, it is possible to suppress the saturated static electricity of the adhesive film after ultraviolet curing. The voltage rises to complete the present invention.

According to the invention, the adhesive film for semiconductor wafer processing shown below can be provided.

[1] An adhesive film for processing a semiconductor wafer, which is an adhesive film for protecting a surface of a semiconductor wafer or fixing a semiconductor wafer, and sequentially includes a substrate layer, an antistatic layer, and an adhesive resin layer, The adhesive resin layer contains an ion conductive additive. [2] The adhesive film for semiconductor wafer processing according to [1], wherein the adhesive resin layer contains an ultraviolet curable adhesive resin. [3] The adhesive film for processing a semiconductor wafer according to the above [2], wherein the ion conductivity in the adhesive resin layer is 100 parts by mass with respect to the ultraviolet curable adhesive resin The content of the additive is 0.01 parts by mass or more and 10 parts by mass or less. [4] The adhesive film for semiconductor wafer processing according to any one of [1] to [3] wherein the ion conductive additive comprises a surfactant selected from the group consisting of a cationic surfactant and an anionic surfactant. One or more of a nonionic surfactant, an amphoteric surfactant, and an ionic liquid. [5] The adhesive film for semiconductor wafer processing according to any one of [1] to [4] wherein the thickness of the adhesive resin layer is 5 μm or more and 550 μm or less. [6] The adhesive film for semiconductor wafer processing according to any one of [1] to [5], which is a back grind tape. [7] The adhesive film for semiconductor wafer processing according to any one of [1] to [6] wherein the antistatic layer contains a conductive polymer. [8] The adhesive film for semiconductor wafer processing according to any one of [1] to [7] wherein the substrate layer and the antistatic layer further comprise a concave-convex absorbent resin Floor. [9] The adhesive film for semiconductor wafer processing according to any one of [1] to [8] wherein the saturated electrostatic voltage of the surface of the adhesive resin layer after ultraviolet curing is measured by the following method V ₁ is 1.0 kV or less. (Method) The adhesive resin layer was irradiated with ultraviolet rays having a dominant wavelength of 365 nm at an ultraviolet ray of 1080 mJ/cm ² at a irradiation intensity of 100 mW/cm ² in an environment of 25 ° C at 25 ° C to make the adhesion. The resin layer is photohardened. Then, a voltage was applied to the surface of the adhesive resin layer for 30 seconds under the conditions of a voltage of 10 kV, a distance between the sample and the electrode of 20 mm, 25 ° C, and 50% RH, and the adhesive resin was calculated in accordance with JIS L1094. The saturated electrostatic voltage (V ₁ ) of the surface of the layer. [10] The adhesive film for semiconductor wafer processing according to any one of the above [1], wherein the adhesion of the surface of the adhesive resin layer after ultraviolet curing measured by the following method It is 0.1 N/cm ² or less. (Method) The adhesion of the surface of the adhesive resin layer was measured by adhering the adhesive resin layer of the adhesive film to a polyimide film at 25 ° C. said adhesive base layer side of the film using a high pressure mercury lamp at an irradiation intensity of 100 mW / cm ² irradiation amount of the ultraviolet ray 1080 mJ / cm ² of 365 nm dominant wavelength of the ultraviolet, the layer of the photo-curing resin adhesive. Then, the polyimide film was peeled off from the adhesive film, and a probe having a diameter of 5 mm and a surface of the adhesive resin layer were used using a probe tack tester as a measuring device. The probe was contacted at a speed of 10 mm/sec, and after contact with a contact load of 0.98 N/cm ² for 10 seconds, the probe was peeled off from the surface of the adhesive resin layer in a vertical direction at a rate of 10 mm/sec.

[Effects of the Invention] According to the present invention, it is possible to provide an adhesive film for processing a semiconductor wafer, which is excellent in antistatic property after ultraviolet curing, and can suppress the amount of static electricity generated when peeling from a semiconductor wafer, and can be stably obtained. High quality semiconductor parts.

Hereinafter, embodiments of the present invention will be described using the drawings. In the drawings, the same components are denoted by the same reference numerals, and the description is omitted as appropriate. In addition, the figure is a schematic view and does not match the actual size ratio. In addition, "A to B" of the numerical range means A or more and B or less unless otherwise specified. In the present embodiment, "(meth)acrylic acid" means both acrylic acid, methacrylic acid, or both acrylic acid and methacrylic acid.

FIG. 1 and FIG. 2 are cross-sectional views schematically showing an example of a configuration of an adhesive film 100 for semiconductor wafer processing according to an embodiment of the present invention. As shown in FIG. 1, the adhesive film 100 for semiconductor wafer processing (hereinafter also referred to as "adhesive film 100") of the present embodiment includes a base material layer 10, an antistatic layer 30, and an adhesive resin layer 40 in this order. And used to protect the surface of the semiconductor wafer or to fix the semiconductor wafer. Further, the adhesive resin layer 40 contains an ion conductive additive.

As described above, in recent years, the technical level required for the viewpoint of the countermeasure against static electricity of the adhesive film for semiconductor wafer processing has been gradually improved. In particular, in the case of a semiconductor wafer in which a bump electrode such as a solder bump or a copper pillar bump is formed on a high-density circuit of a semiconductor wafer equipped with a high-density circuit, there is a static electricity This tends to cause damage (short circuit) of the circuit including the bump electrodes formed on the semiconductor wafer, and thus such a requirement is more remarkable. Therefore, an adhesive film for semiconductor wafer processing which is more excellent in antistatic property is desired.

According to the study by the inventors of the present invention, it has been clarified that the adhesive film in which the base film, the antistatic layer, and the adhesive layer are sequentially laminated as described in Patent Document 1 does not sufficiently satisfy the antistatic property. More specifically, it is clear that the adhesive film described in Patent Document 1 has a large increase in the saturated electrostatic voltage of the adhesive layer after ultraviolet curing, and the antistatic property is seriously deteriorated.

The present inventors have repeatedly conducted diligent research in order to achieve the above problems. As a result, it was found for the first time that the adhesion of the adhesive film after ultraviolet curing can be suppressed by adding an ion conductive additive to the adhesive resin layer for the adhesive film including the base material layer, the antistatic layer, and the adhesive resin layer in this order. The rise in electrostatic voltage. In other words, the adhesive film 100 for semiconductor wafer processing of the present embodiment has the above-described layer structure, and is excellent in antistatic property after ultraviolet curing, and can suppress the amount of static electricity generated when peeling from the semiconductor wafer. Stable access to high quality semiconductor parts.

In the adhesive film 100 of the present embodiment, the saturated electrostatic voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing measured by the following method is preferably 1.0 kV or less, more preferably 0.5 kV or less. (Method) The adhesive resin layer 40 was irradiated with ultraviolet rays having a dominant wavelength of 365 nm at an ultraviolet ray of 1080 mJ/cm ² at an irradiation intensity of 100 mW/cm ² in an environment of 25 ° C in an environment of 25 ° C to form an adhesive resin layer 40. Light hardening. Then, a voltage was applied to the surface of the adhesive resin layer 40 under the conditions of a voltage of 10 kV and a distance between the sample and the electrode of 20 mm, 25 ° C, and 50% RH for 30 seconds, and the adhesive resin layer 40 was calculated in accordance with JIS L1094. The saturated electrostatic voltage (V ₁ ) of the surface.

By setting the saturated electrostatic voltage V ₁ of the adhesive resin layer 40 which has been cured by ultraviolet rays to the upper limit or less, the antistatic property on the surface of the semiconductor wafer can be further improved. The lower limit of the saturated electrostatic voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing is, for example, 0.01 kV or more, preferably 0 kV.

In the present embodiment, the saturated electrostatic voltage of the adhesive resin layer 40 after ultraviolet curing can be adjusted by appropriately adjusting the type or blending ratio of each component constituting the adhesive resin layer 40, the thickness of the adhesive resin layer 40, and the like. The V ₁ control is equal to or less than the upper limit value. In the above, for example, the presence or absence of the ion conductive additive in the adhesive resin layer 40 or the thickness of the adhesive resin layer 40 is used as the saturated electrostatic voltage V ₁ for the adhesive resin layer 40 after ultraviolet curing. The elements that require a range of values. For example, when the content of the ion conductive additive in the adhesive resin layer 40 is increased or the thickness of the adhesive resin layer 40 is made thin, the saturated electrostatic voltage V ₁ can be lowered.

In the adhesive film 100 of the present embodiment, when the saturated electrostatic voltage on the surface of the adhesive resin layer 40 cured by ultraviolet rays measured by the following method is V ₂ , V ₁ /V _{2 is} preferably 5.0 or less. It is preferably 3.0 or less, and further preferably 2.5 or less. When V ₁ /V ₂ is at most the above upper limit value, the amount of static electricity generated when peeling off from the semiconductor wafer can be more stably suppressed, and a semiconductor component excellent in quality can be obtained more stably. (Method) The adhesive resin layer 40 was irradiated with ultraviolet rays having a wavelength of 200 mJ/cm ² at a main wavelength of 365 nm at an irradiation intensity of 100 mW/cm ² in an environment of 25 ° C in an environment of 25 ° C to form an adhesive resin layer 40. Light hardening. Then, a voltage was applied to the surface of the adhesive resin layer 40 under the conditions of a voltage of 10 kV and a distance between the sample and the electrode of 20 mm, 25 ° C, and 50% RH for 30 seconds, and the adhesive resin layer 40 was calculated in accordance with JIS L1094. The saturated electrostatic voltage (V ₂ ) of the surface.

In the adhesive film 100 of the present embodiment, the half life of the saturated electrostatic voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing is preferably 20 seconds or less, more preferably 10 seconds or less, and still more preferably 5 seconds or less. It is less than 1 second. Here, the half-saturation electrostatic voltage V ₁ refers to a saturated static voltage measurement V _1, the value of the electrostatic voltage is applied to the end surface of the voltage adhesion resin layer 40 is reduced to half the time. In the adhesive film 100 of the present embodiment, since the saturated electrostatic voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing is equal to or less than the above upper limit value, such a short half life can be achieved, and the antistatic property can be excellent. Adhesive film 100.

In the adhesive film 100 of the present embodiment, the adhesion force on the surface of the adhesive resin layer 40 after ultraviolet curing measured by the following method is preferably 0.1 N/cm ² or less, more preferably 0.05 N/cm ² or less. Preferably, it is 0.01 N/cm ² or less. When the adhesion of the surface of the adhesive resin layer 40 after ultraviolet curing is not more than the above upper limit, it is easier to peel off the adhesive film 100 from the surface of the semiconductor wafer, and it is possible to further suppress a part of the adhesive resin layer 40. It remains on the surface of the semiconductor wafer, or a defect occurs in the semiconductor wafer due to peeling of the adhesive film 100. (Method) The adhesion of the surface of the adhesive resin layer 40 was measured by the following method: The adhesive resin layer 40 of the adhesive film 100 was bonded to a polyimide film (product name: Kapton 200H, East) Manufactured by Du Pont-Toray Co., Ltd., using a high-pressure mercury lamp on the substrate layer 10 side of the adhesive film 100 at an irradiation intensity of 100 mW/cm ² at a radiation intensity of 1080 mJ/cm ² at 25 ° C. The ultraviolet light having a dominant wavelength of 365 nm hardens the adhesive resin layer 40. Then, the polyimide film is peeled off from the adhesive film 100, and a probe adhesion tester (for example, "TESTING MACHINES Inc." probe adhesion tester: model 80 is used. -02-01") As a measuring device, a probe having a diameter of 5 mm was brought into contact with the surface of the adhesive resin layer 40 at a speed of 10 mm/sec, and contacted with a contact load of 0.98 N/cm ² for 10 seconds, and then 10 The probe was peeled off from the surface of the adhesive resin layer 40 in the vertical direction at a speed of mm/sec.

The thickness of the entire adhesive film 100 of the present embodiment is preferably 25 μm or more and 1000 μm or less, and more preferably 50 μm or more and 600 μm or less in terms of the balance between the mechanical properties and the operability.

The adhesive film 100 of the present embodiment is used to protect the surface of the semiconductor wafer or to fix the semiconductor wafer in the manufacturing process of the semiconductor device, and more specifically, backgrinding, which is one of the manufacturing steps of the semiconductor device. The step is preferably used as a back grinding tape used to protect a circuit forming surface of a semiconductor wafer (ie, a circuit surface including a circuit pattern). When the semiconductor wafer to be attached is a semiconductor wafer to which a circuit including fine wiring of bump electrodes is applied, the static electricity generated when the adhesive film is peeled off from the semiconductor wafer is likely to be caused. The circuit formed on the semiconductor wafer is broken, that is, electrostatically destroyed. However, by using the adhesive film 100 of the present embodiment, even a semiconductor wafer having bump electrodes formed on such a surface can be more reliably suppressed. Electrostatic damage, etc.

The semiconductor wafer to which the adhesive film 100 of the present embodiment can be applied is not particularly limited, and examples thereof include a germanium wafer.

Next, each layer constituting the adhesive film 100 for semiconductor wafer processing of the present embodiment will be described.

(Base Material Layer) The base material layer 10 is a layer provided for the purpose of improving the properties such as workability, mechanical properties, and heat resistance of the adhesive film 100. The base material layer 10 is not particularly limited as long as it has mechanical strength capable of withstanding an external force applied when processing a semiconductor wafer, and examples thereof include a resin film. As the resin constituting the resin film, a known thermoplastic resin can be used. For example, one or two or more selected from the group consisting of polyolefins such as polyethylene, polypropylene, poly(4-methyl-1-pentene), and poly(1-butene); polyterephthalic acid; Polyester such as ethylenediester or polybutylene terephthalate; polyamine; nylon-6, nylon-66, poly(xamethylenediphthalamide); polyacrylate; polymethacrylate; polychlorinated Ethylene; polyether quinone imine; ethylene vinyl acetate copolymer; polyacrylonitrile; polycarbonate; polystyrene; ionic polymer; polyfluorene; polyether oxime; polyphenylene ether. Among these, from the viewpoint of semiconductor wafer protection, one or more selected from the group consisting of polypropylene, polyethylene terephthalate, polyamine, and ethylene-vinyl acetate copolymer are preferable. More preferably, it is one or more selected from the group consisting of polyethylene terephthalate and ethylene-vinyl acetate copolymer.

The base material layer 10 may be a single layer or may be two or more layers. In addition, the form of the resin film used for forming the base material layer 10 may be a stretched film or a film extending in the uniaxial direction or the biaxial direction, but the viewpoint of improving the mechanical strength of the base material layer 10 is considered. In general, a film extending in the uniaxial direction or the biaxial direction is preferred.

The thickness of the base material layer 10 is preferably 10 μm or more and 500 μm or less, more preferably 20 μm or more and 300 μm or less, and further preferably 25 μm or more and 150 μm or less from the viewpoint of obtaining good film properties. The base material layer 10 may be subjected to surface treatment in order to improve adhesion to other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coating treatment, or the like may be performed.

(Adhesive Resin Layer) The adhesive film 100 of the present embodiment includes the adhesive resin layer 40. The adhesive resin layer 40 is a layer that comes into contact with and adheres to the surface of the semiconductor wafer when the adhesive film 100 for semiconductor wafer processing is attached to the semiconductor wafer.

The adhesive resin layer 40 is preferably a layer formed of an ultraviolet curable adhesive containing an ultraviolet curable adhesive resin. Examples of the ultraviolet curable adhesive include a (meth)acrylic adhesive, an anthrone-based adhesive, and a urethane-based adhesive. The (meth)acrylic adhesive contains a (meth)acrylic adhesive resin as an ultraviolet curable adhesive resin as an essential component. The anthrone-based adhesive contains an anthrone-based adhesive resin as an ultraviolet-curable adhesive resin as an essential component. The urethane-based adhesive contains an urethane-based adhesive resin as an ultraviolet curable adhesive resin as an essential component. Among these, a (meth)acrylic adhesive is preferred from the viewpoint of easily adjusting the adhesion.

The (meth)acrylic-based adhesive is exemplified by a (meth)acrylic adhesive resin having a polymerizable carbon-carbon double bond in a molecule and having two or more polymerizable carbons in the molecule. A low molecular weight compound having a carbon double bond and a photoinitiator are obtained by crosslinking the (meth)acrylic adhesive resin by a crosslinking agent as necessary.

The (meth)acrylic adhesive resin having a polymerizable carbon-carbon double bond in the molecule can be specifically obtained in the following manner. First, a monomer having an ethylenic double bond is copolymerized with a copolymerizable monomer having a functional group (P). Then, a functional group (P) contained in the copolymer and a monomer having a functional group (Q) capable of undergoing an addition reaction, a condensation reaction, and the like with the functional group (P) are added to the monomer. The reaction is carried out in a state where the bond remains, and a polymerizable carbon-carbon double bond is introduced into the copolymer molecule.

As the monomer having an ethylenic double bond, for example, one or two or more kinds are used from the following compounds: methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth)acrylic acid Alkyl acrylate such as butyl ester or ethyl (meth) acrylate and alkyl (meth) acrylate monomer, vinyl acetate such as vinyl acetate, (meth) acrylonitrile, (meth) propylene hydride A monomer having an ethylenic double bond such as an amine or styrene.

Examples of the copolymerizable monomer having a functional group (P) include (meth)acrylic acid, maleic acid, 2-hydroxyethyl (meth)acrylate, and glycidyl (meth)acrylate. N-methylol (meth) acrylamide, (meth) propylene methoxyethyl isocyanate, and the like. These may be used alone or in combination of two or more. The ratio of the monomer having an ethylenic double bond to the copolymerizable monomer having a functional group (P) is preferably 70% by mass to 99% by mass based on the former, and the latter is 30% by mass to 1% by mass. Further, it is preferably 80% by mass to 95% by mass based on the former, and the latter is 20% by mass to 5% by mass. Examples of the monomer having a functional group (Q) include the same monomers as the copolymerizable monomer having the functional group (P).

a functional group (P) and a functional group (Q) which are reacted when a polymerizable carbon-carbon double bond is introduced into a copolymer of a monomer having an ethylenic double bond and a copolymerizable monomer having a functional group (P) The combination is preferably a combination of a carboxyl group and an epoxy group, a carboxyl group and an aziridine group, a hydroxyl group and an isocyanate group, which are likely to cause an addition reaction. In addition, it is not limited to the addition reaction, and any reaction can be used as long as it can easily introduce a polymerizable carbon-carbon double bond such as a condensation reaction between a carboxyl group and a hydroxyl group.

Examples of the low molecular weight compound having two or more polymerizable carbon-carbon double bonds in the molecule include tripropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and tetramethylol group. Methane tetraacrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like. These may be used alone or in combination of two or more. The amount of the low molecular weight compound having two or more polymerizable carbon-carbon double bonds in the molecule is preferably from 0.1 part by mass to 20 parts by mass, based on 100 parts by mass of the (meth)acrylic adhesive resin. It is preferably 5 parts by mass to 18 parts by mass.

As the photoinitiator, benzoin, benzoin isopropyl ether, benzoin isobutyl ether, benzophenone, misch ketone, chlorothiazolone, dodecyl thioxanthone, dimethyl sulfide Xanthone, diethyl thioxanthone, acetophenone diethyl ketal, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-benzene Propane-1-one and the like. These may be used alone or in combination of two or more. The amount of the photoinitiator to be added is preferably from 0.1 part by mass to 15 parts by mass, more preferably from 5 parts by mass to 10 parts by mass, per 100 parts by mass of the (meth)acrylic adhesive resin.

A crosslinking agent may also be added to the ultraviolet curable adhesive. Examples of the crosslinking agent include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, and diglycerin polyglycidyl ether; tetramethylol methane- Tri-β-aziridine propionate, trimethylolpropane-tri-β-aziridine propionate, N,N'-diphenylmethane-4,4'-bis(1-nitrogen Aziridine-based compound such as propidium carboxy decylamine, N,N'-hexamethylene-1,6-bis(1-aziridinecarboxy decylamine); tetramethylene diisocyanate, hexamethylene An isocyanate compound such as a diisocyanate or a polyisocyanate. The ultraviolet curable adhesive may be any of a solvent type, an emulsion type, a hot melt type, and the like.

The content of the crosslinking agent is usually preferably in a range in which the number of functional groups in the crosslinking agent is not more than the number of functional groups in the (meth)acrylic adhesive resin. However, when a functional group is newly formed in the crosslinking reaction or when the crosslinking reaction is slow, the crosslinking agent may be excessively contained as needed. From the viewpoint of improving the heat resistance of the adhesive resin layer 40 or the balance of the adhesion, the crosslinking agent in the (meth)acrylic adhesive is 100 parts by mass of the (meth)acrylic adhesive resin. The content is preferably 0.1 part by mass or more and 15 parts by mass or less.

The adhesive resin layer 40 of the present embodiment contains an ion conductive additive. Thereby, the antistatic property of the adhesive resin layer 40 can be improved. Further, it is possible to suppress an increase in the saturated electrostatic voltage of the adhesive film 100 after the ultraviolet curing. Examples of the ion conductive additive include a cationic surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant, and an ionic liquid. From the viewpoint of further improving the antistatic property of the adhesive resin layer 40, at least one selected from the group consisting of a cationic surfactant and an anionic surfactant is preferable, and a cationic surfactant is more preferable.

Examples of the cationic surfactant include dodecyltrimethylammonium chloride, tetradecyldimethylbenzylammonium chloride, cetyldimethylbenzylammonium chloride, and stearyl group. Dimethylbenzylammonium chloride, tetradecyltrimethylammonium chloride, cetyltrimethylammonium chloride, octadecyltrimethylammonium chloride, di-dodecyldiamine Ammonium chloride, di-tetradecyldimethylammonium chloride, di-hexadecyldimethylammonium chloride, di-octadecyldimethylammonium chloride, dodecylbenzyl Dimethylammonium chloride, cetylbenzyldimethylammonium chloride, octadecylbenzyldimethylammonium chloride, palmityl trimethylammonium chloride, oleyl trimethyl chloride Ammonium, dipalmitylbenzylmethylammonium chloride, dioleylbenzylmethylammonium chloride, and the like. The cationic surfactant may, for example, be a quaternary ammonium salt or an amine salt, and is preferably a quaternary ammonium salt. Among them, at least one selected from the group consisting of tetradecyldimethylbenzylammonium chloride, cetyldimethylbenzylammonium chloride, and stearyldimethylbenzylammonium chloride is preferred.

Examples of the anionic surfactant include diammonium dodecyl diphenyl ether disulfonate, sodium dodecyl diphenyl ether disulfonate, and calcium lauryl diphenyl ether disulfonate. An alkyl diphenyl ether disulfonate such as sodium alkyl diphenyl ether disulfonate; an alkylbenzene sulfonate such as sodium dodecylbenzenesulfonate or ammonium dodecylbenzenesulfonate; An alkyl sulfate salt such as sodium sulfate or ammonium lauryl sulfate; an aliphatic carboxylate such as sodium fatty acid or potassium oleate; or a sulfate salt containing a polyoxyalkylene unit (for example, sodium polyoxyethylene alkyl ether sulfate, Polyoxyethylene alkyl ether sulfate salt such as polyoxyethylene alkyl ether sulfate; polyoxyethylene alkylphenyl ether sulfate such as polyoxyethylene alkylphenyl ether sulfate or polyoxyethylene alkylphenyl ether ammonium sulfate Ester salt; polyoxyethylene polycyclic phenyl ether sulfate such as polyoxyethylene polycyclic phenyl ether sulfate, polyoxyethylene polycyclic phenyl ether ammonium sulfate, etc.; naphthalenesulfonic acid such as sodium naphthalenesulfonic acid formaldehyde condensate Formaldehyde condensate salt; sodium sulfosuccinate dialkyl ester, sulfosuccinate disodium monoalkyl ester and other alkyl sulfosuccinate; polyoxyethylene-polyoxypropylene An alcohol ether sulfate; a sulfonate or a surfactant having a sulfate group and a polymerizable carbon-carbon (unsaturated) double bond in the molecule.

Examples of the nonionic surfactant include polyoxyalkylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene tridecyl ether, and polyoxyethylene oleyl ether. Polyether alkylene phenyl ether compound such as polyether octyl phenyl ether or polyoxyethylene nonyl phenyl ether, polyoxyalkylene polycyclic ring such as polyoxyethylene polycyclic phenyl ether An ether compound containing a polyoxyalkylene unit such as a phenyl ether compound; a polyoxyalkylene alkyl ester compound such as polyoxyethylene monolaurate, polyoxyethylene monostearate or polyoxyethylene monooleate a polyoxyalkylalkylamine compound such as polyoxyethylene alkylamine; sorbitan monolaurate, sorbitan monostearate, sorbitan trioleate, polyoxyethylene A sorbitan compound such as sorbitan monolaurate or polyoxyethylene sorbitan monooleate.

Examples of the amphoteric surfactant include lauryl betaine and lauryl dimethyl amine oxide.

These ion conductive additives may be used alone or in combination of two or more. The content of the ion conductive additive in the adhesive resin layer 40 is preferably 0.01 parts by mass or more and 10 parts by mass or less, more preferably 0.1 part by mass or more and 5 parts by mass or less, based on 100 parts by mass of the ultraviolet curable adhesive resin. Further, it is preferably 0.1 part by mass or more and 2 parts by mass or less.

The adhesive resin layer 40 can be formed, for example, by applying an adhesive coating liquid onto the antistatic layer 30. As a method of applying the adhesive coating liquid, a conventionally known coating method such as a roll coater method, a reverse roll coater method, a gravure roll method, a bar coating method, a notch wheel coater can be employed. Method, die coating machine method, etc. The drying conditions of the applied adhesive are not particularly limited, but it is usually preferably dried in a temperature range of 80 ° C to 200 ° C for 10 seconds to 10 minutes. Further, it is preferably dried at 80 ° C to 170 ° C for 15 seconds to 5 minutes. In order to sufficiently promote the crosslinking reaction of the crosslinking agent and the (meth)acrylic adhesive resin, the drying of the adhesive coating liquid may be carried out at 40 to 80 ° C for 5 to 300 hours.

In the adhesive film 100 of the present embodiment, the thickness of the adhesive resin layer 40 is usually 5 μm or more and 550 μm or less, preferably 10 μm or more and 400 μm or less, and more preferably 30 μm or more and 300 μm or less. It is preferably 50 μm or more and 250 μm or less. When the thickness of the adhesive resin layer 40 is within the above range, the balance between the adhesion to the surface of the semiconductor wafer and the handleability is good. In addition, when the adhesive film 100 of the present embodiment further includes the uneven-absorbent resin layer 20 to be described later, the thickness of the adhesive resin layer 40 is preferably 100 μm or less, more preferably 50 μm or less, and further preferably It is 30 μm or more, more preferably 25 μm or less, and even more preferably 20 μm or less, and particularly preferably 15 μm or less. Thereby, the distance between the surface of the adhesive resin layer 40 and the antistatic layer 30 can be reduced, and as a result, the antistatic property of the adhesive film 100 can be further improved. In addition, when the adhesive film 100 of the present embodiment further includes the uneven-absorbent resin layer 20 to be described later, the lower limit of the thickness of the adhesive resin layer 40 is not particularly limited, but the adhesive strength is good. In other words, it is preferably 0.5 μm or more, more preferably 1.0 μm or more, further preferably 3.0 μm or more, and particularly preferably 5.0 μm or more.

(Antistatic Layer) The adhesive film 100 of the present embodiment includes the antistatic layer 30. Thereby, the antistatic property of the adhesive film 100 can be improved while maintaining the adhesiveness of the adhesive film 100, and the amount of static electricity generated when the adhesive film 100 is peeled off from the semiconductor wafer can be suppressed.

The material constituting the antistatic layer 30 preferably contains a conductive polymer from the viewpoint of reducing the surface resistance value of the antistatic layer 30 and suppressing the generation of static electricity accompanying the peeling. Examples of the conductive polymer include a polythiophene-based conductive polymer, a polypyrrole-based conductive polymer, a polyaniline-based conductive polymer, and a poly(p-phenylenevinylene)-based conductive polymer. Quinoxaline-based conductive polymer. From the viewpoint of a good balance between optical properties, appearance, antistatic property, coating property, stability, and the like, a polythiophene-based conductive polymer is preferable. Examples of the polythiophene-based conductive polymer include polyethylene dioxythiophene and polythiophene. These conductive polymers may be used alone or in combination of two or more.

The material forming the antistatic layer 30 may further include, for example, a doping agent, a binder resin, or the like. The dopant functions as a dopant, and more reliably imparts (doping) conductivity to the conductive polymer, and examples thereof include a sulfonic acid compound.

Examples of the sulfonic acid compound include p-toluenesulfonic acid, benzenesulfonic acid, ethylbenzenesulfonic acid, octylbenzenesulfonic acid, dodecylbenzenesulfonic acid, mesitylenesulfonic acid, m-xylenesulfonic acid, and poly Styrene sulfonic acid, polyvinyl sulfonic acid, and the like. From the viewpoint of improving the solubility or water dispersibility of the conductive polymer, polystyrenesulfonic acid or polyvinylsulfonic acid is preferred. The sulfonic acid compound may be used alone or in combination of two or more.

By adding such a dopant, the conductive polymer and the sulfonic acid compound partially react to form a sulfonate, and the antistatic function of the antistatic layer 30 is further enhanced by the action of the sulfonate. The blending ratio of the dopant is, for example, 100 parts by mass to 300 parts by mass based on 100 parts by mass of the conductive polymer. As a combination of a conductive polymer and a dopant, a combination of polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS) is preferred because it is more excellent in antistatic property.

The material constituting the antistatic layer 30 may further include a binder resin from the viewpoint of improving film formation properties, adhesion, and the like. Examples of the binder resin include a polyurethane resin, a polyester resin, a (meth)acrylic resin, a polyether resin, a cellulose resin, a polyvinyl alcohol resin, and an epoxy resin. Polyvinylpyrrolidone, polystyrene resin, polyethylene glycol, pentaerythritol, and the like. The binder resin may be used alone or in combination of two or more. The content of the binder resin is, for example, 10 parts by mass to 500 parts by mass based on 100 parts by mass of the conductive polymer.

The thickness of the antistatic layer 30 is preferably 0.01 μm or more and 10 μm or less, more preferably 0.01 μm or more and 5 μm or less, and further preferably 0.01 μm or more and 1 μm or less from the viewpoint of antistatic performance.

(Concave and Absorbing Resin Layer) As shown in FIG. 2, the adhesive film 100 of the present embodiment preferably further includes a concavo-convex-absorbent resin layer 20 between the base material layer 10 and the antistatic layer 30. As a result, the thickness of the adhesive resin layer 40 can be reduced while the unevenness of the adhesive film 100 is improved, and the distance between the surface of the adhesive resin layer 40 and the antistatic layer 30 can be reduced. As a result, The antistatic property of the adhesive film 100 can be made better.

The density of the uneven absorbent resin layer 20 is preferably from 800 kg/m ³ to 990 kg/m ³ , more preferably from 830 kg/m ³ to 980 kg/m, from the viewpoint of balance between mechanical strength and unevenness followability. ³ , and then preferably 850 kg / m ³ ~ 970 kg / m ³ .

The resin constituting the uneven-absorbent resin layer 20 is not particularly limited as long as it exhibits unevenness absorption, and for example, a thermoplastic resin can be used. More specifically, an olefin resin, an ethylene/polar monomer copolymer, an Acrylonitrile Butadiene Styrene (ABS) resin, a vinyl chloride resin, a vinylidene chloride resin, (A) Acrylic resin, polyamine resin, fluorine resin, polycarbonate resin, polyester resin, and the like. Among these, at least one selected from the group consisting of an olefin resin and an ethylene/polar monomer copolymer is preferred.

Examples of the olefin-based resin include linear low-density polyethylene (LLDPE), low-density polyethylene, high-density polyethylene, polypropylene, and α-olefins containing ethylene and carbon atoms of 3 to 12. Copolymer of ethylene/α-olefin copolymer, propylene·α-olefin copolymer containing propylene and carbon number 4 to 12, ethylene·cyclic olefin copolymer, ethylene·α-olefin·cyclic olefin copolymer Things and so on. Examples of the ethylene·polar monomer copolymer include ethylene·ethyl (meth)acrylate copolymer, ethylene·methyl (meth)acrylate copolymer, ethylene·propyl (meth)acrylate copolymer, and ethylene· Ethylene·unsaturated carboxylic acid ester copolymer such as butyl (meth)acrylate; ethylene·vinyl acetate copolymer, ethylene·vinyl propionate copolymer, ethylene·vinyl butyrate copolymer, ethylene·hard fat An ethylene/vinyl ester copolymer such as a vinyl acetate copolymer. The resin constituting the uneven-absorbent resin layer 20 may be used singly or in combination of two or more kinds.

Examples of the α-olefin having 3 to 12 carbon atoms in the ethylene·α-olefin copolymer include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, and 1-hexene. 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, etc., preferably propylene, 1-butene Alkene and the like.

Among these, in terms of excellent adhesion followability at the time of attachment, it is preferably at least one selected from the group consisting of low density polyethylene, polypropylene, ethylene·propylene copolymer, ethylene·1-butene. An ethylene/α-olefin copolymer such as a copolymer, an ethylene/propylene, a terpolymer of an α-olefin having 4 to 12 carbon atoms, or a propylene/1-butene-α-olefin having 5 to 12 carbon atoms The copolymer; an ethylene-vinyl acetate copolymer or the like is more preferably at least one selected from the group consisting of ethylene-propylene copolymers and ethylene-vinyl acetate copolymers.

The thickness of the uneven-absorbent resin layer 20 is not particularly limited as long as it is a thickness of the unevenness that can be embedded in the uneven surface of the semiconductor wafer, and is preferably, for example, 10 μm or more and 500 μm or less, and more preferably 20 μm or more. 400 μm or less, more preferably 30 μm or more and 300 μm or less, and particularly preferably 50 μm or more and 250 μm or less.

In the adhesive film 100 of the present embodiment, an adhesive layer (not shown) may be provided between the respective layers. By this bonding layer, the adhesion between the layers can be improved. Further, the adhesive film 100 of the present embodiment can further laminate a release film.

Next, an example of a method of manufacturing the adhesive film 100 for semiconductor wafer processing of the present embodiment will be described.

First, the uneven-absorbent resin layer 20 is formed on one surface of the base material layer 10 by an extrusion lamination method. Then, a predetermined conductive material is applied onto a release film prepared separately and dried to form an antistatic layer 30, and the antistatic layer 30 is laminated on the uneven absorbent resin layer 20. Then, the adhesive coating liquid is applied onto the antistatic layer 30 and dried to form the adhesive resin layer 40, whereby the adhesive film 100 is obtained. Further, the base material layer 10 and the uneven-absorbent resin layer 20 can be formed by co-extrusion molding, and the film-form base material layer 10 and the film-shaped uneven-absorbent resin layer 20 can be laminated (laminated). form.

Next, an example of a back surface grinding method (also referred to as back grinding) of a semiconductor wafer using the adhesive film 100 for semiconductor wafer processing of the present embodiment will be described. In the back surface grinding method of the semiconductor wafer of the present embodiment, the adhesive film 100 for semiconductor wafer processing of the present embodiment is used as a back surface polishing tape when the back surface of the semiconductor wafer is ground.

First, the release film is peeled off from the adhesive resin layer 40 of the adhesive film 100, the surface of the adhesive resin layer 40 is exposed, and the circuit formation surface of the semiconductor wafer is attached to the adhesive resin layer 40. Then, the semiconductor wafer is fixed to a chuck table or the like of the grinder via the base material layer 10 of the adhesive film 100, and the back surface (circuit non-formed surface) of the semiconductor wafer is ground. After the grinding is completed, the adhesive film 100 is peeled off. The chemical etching step may be performed after the end of the grinding of the semiconductor wafer is completed and before the adhesive film 100 is peeled off. Further, after the adhesive film 100 is peeled off as needed, the back surface of the semiconductor wafer is subjected to a treatment such as water washing or plasma cleaning.

In the back grinding operation, the thickness of the semiconductor wafer before the grinding is usually 500 μm to 1000 μm, and the grinding is performed to a level of usually about 100 μm to 600 μm depending on the type of the semiconductor wafer or the like. It is sometimes cut to thinner than 100 μm as needed. The thickness of the semiconductor wafer before the grinding is appropriately determined by the diameter, type, and the like of the semiconductor wafer, and the thickness of the wafer after the grinding is appropriately determined depending on the size of the obtained wafer, the type of the circuit, and the like.

The operation of attaching the semiconductor wafer to the adhesive film 100 may be performed manually, but is usually performed by a device called a self-adhesive machine to which a roll-shaped adhesive film is attached.

As the back grinding method, a known grinding method such as a throughfeed method or an infeed method can be employed. Each of the grinding is performed while pouring water onto the semiconductor wafer and the grindstone and cooling it. After the back grinding is completed, chemical etching is performed as needed. The chemical etching can be performed by immersing the semiconductor wafer in an acidic aqueous solution selected from a single or mixed liquid containing hydrofluoric acid, nitric acid, sulfuric acid, acetic acid or the like in a state in which the adhesive film 100 is adhered, and oxidizing. In an etching solution in a group consisting of an aqueous alkaline solution such as a potassium aqueous solution or an aqueous sodium hydroxide solution. This etching is performed for the purpose of removing strain generated on the back surface of the semiconductor wafer, further thinning of the wafer, removal of an oxide film, or the like, and pretreatment for forming an electrode on the back surface.

After the back grinding and the chemical etching are completed, the adhesive film 100 is peeled off from the surface of the semiconductor wafer, and the series of operations are sometimes performed manually, but it is usually performed by a device called an automatic peeling machine.

The surface of the semiconductor wafer after the adhesive film 100 is peeled off is washed as needed. Examples of the cleaning method include wet cleaning such as water washing and solvent cleaning, and dry cleaning such as plasma cleaning. In the case of wet cleaning, ultrasonic cleaning can also be used in combination. These cleaning methods are appropriately selected depending on the contamination state of the surface of the semiconductor wafer.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than the above may be employed. [Examples]

Hereinafter, the present invention will be specifically described by way of Examples and Comparative Examples, but the present invention is not limited thereto.

The details of the materials used in the production of the adhesive film are as follows.

<Substrate layer> Polyethylene terephthalate film (thickness 50 μm)

<Resin for forming a concave-convex-absorbing resin layer> Concave-convex-absorbing resin 1: Ethylene-vinyl acetate copolymer (density: 960 kg/m ³ , manufactured by Du Pont-Mitsui Polychemicals Co., Ltd.) EVAFLEX EV150")

<Material for forming an antistatic layer> Material for forming an antistatic layer 1: Conductive material containing polyethylene dioxythiophene/polystyrenesulfonic acid (PEDOT/PSS) (manufactured by Nagase ChemteX Co., Ltd., product Name: Denatron (P-504CT)

<Ion Conductive Additive> Ion Conductive Additive 1: Tetradecyldimethylbenzylammonium chloride (manufactured by NOF Corporation, trade name: Nissan Cation M ₂ -100)

<Photoinitiator> Photoinitiator 1: benzyldimethylketal (manufactured by BASF Corporation, trade name: Irgacure 651)

<Coating Liquid 1 for Adhesive Resin Layer> 77 parts by mass of n-butyl acrylate, 16 parts by mass of methyl methacrylate, 16 parts by mass of 2-hydroxyethyl acrylate, and benzammonium peroxide as a polymerization initiator 0.5 parts by mass of the mixture. This was placed in a nitrogen-substituted flask containing 20 parts by mass of toluene and 80 parts by mass of ethyl acetate, and the mixture was stirred at 85 ° C for 5 hours, and further stirred for 5 hours to cause a reaction. After the completion of the reaction, the solution was cooled, and 10 parts by mass of toluene and 7 parts by mass of methacryloxyethyl isocyanate (manufactured by Showa Denko Co., Ltd., product name: Karenz MOI) were added thereto. 0.02 parts by mass of dibutyltin dilaurate was allowed to react at 85 ° C for 12 hours while blowing air to obtain a solution of the adhesive polymer 1 into which a polymerizable carbon-carbon double bond was introduced. To the solution, benzyl dimethyl ketal (manufactured by BASF Co., Ltd., Irgacure 651) 7 mass was added to the solution with respect to 100 parts by mass of the copolymer (solid content). And an isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals Co., Ltd., trade name: Olestar P49-75S) in an amount of 2 parts by mass, having two or more polymerizable carbon-carbon double bonds in one molecule. Dipentaerythritol hexaacrylate of low molecular weight compound (manufactured by Toagos Corporation, trade name: Aronix M-400) 12 parts by mass, ion conductive additive 1: tetradecyl dimethyl benzyl chloride The coating liquid 1 for an adhesive resin layer was obtained by the ammonium salt (manufactured by Nippon Oil Co., Ltd., Nissan Cation M ₂ -100) in an amount of 0.5 part by mass.

<Coating Liquid 2 for Adhesive Resin Layer> The coating liquid 2 for an adhesive resin layer was obtained in the same manner as the coating liquid 1 for an adhesive resin layer, except that the ion conductive additive 1 was not added.

<Coating Liquid 3 for Adhesive Resin Layer> 48 parts by mass of ethyl acrylate, 27 parts by mass of 2-ethylhexyl acrylate, 20 parts by mass of methyl acrylate, and 5 parts by mass of glycidyl methacrylate, and as a polymerization The initiator was mixed with 0.5 parts by mass of benzamidine peroxide. This was placed in a nitrogen-substituted flask containing 65 parts by mass of toluene and 50 parts by mass of ethyl acetate, and the mixture was stirred at 80 ° C for 5 hours, and further stirred for 5 hours to cause a reaction. After the completion of the reaction, the solution was cooled, and 25 parts by mass of xylene, 2.5 parts by mass of acrylic acid, and 0.5 part by mass of the ion conductive additive 1: tetradecyldimethylbenzylammonium chloride were added thereto while blowing. The air was allowed to react at 85 ° C for 32 hours to obtain a solution of the adhesive polymer 3 into which a polymerizable carbon-carbon double bond was introduced. To the solution, benzyl dimethyl ketal (manufactured by BASF Co., Ltd., Irgacure 651) 7 mass was added to the solution with respect to 100 parts by mass of the copolymer (solid content). And an isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals Co., Ltd., trade name: Olestar P49-75S) in an amount of 2 parts by mass, having two or more polymerizable carbon-carbon double bonds in one molecule. The dipentaerythritol hexaacrylate (manufactured by Toagosei Co., Ltd., trade name: Aronix M-400) of the low molecular weight compound was used in an amount of 12 parts by mass to obtain a coating liquid 3 for an adhesive resin layer.

[Example 1] On the polyethylene terephthalate film to be a base material layer, the uneven absorbent resin 1 which is a concave-convex absorbent resin layer was extrusion-laminated at a thickness of 195 μm to obtain a two-layer laminate. membrane. Then, the antistatic layer forming material 1 is applied onto a separately prepared release film and dried to form an antistatic film, and the antistatic film is laminated on the uneven absorbent resin layer, thereby forming a thickness. 0.1 μm antistatic layer. Then, the coating liquid 1 for an adhesive resin layer was applied onto the antistatic layer of the obtained laminated film, and then dried to form an adhesive resin layer having a thickness of 40 μm to obtain an adhesive film. The following evaluation was performed for the obtained adhesive film. The results obtained are shown in Table 1.

[Example 2 and Example 3, Comparative Example 1 to Comparative Example 4] The presence or absence of the formation of the antistatic layer, the thickness of the adhesive resin layer, the type of the coating liquid for the adhesive resin layer, and the like were changed to those in Table 1. An adhesive film was produced in the same manner as in Example 1 except for the above. The following evaluations were performed for each of the obtained adhesive films. The results obtained are shown in Table 1, respectively.

<Evaluation> (1) Measurement of saturated electrostatic voltage Using a high-pressure mercury lamp (UVX-02528S1AJA02 manufactured by Oxtail (USHIO) Motor Co., Ltd.) at an irradiation intensity of 100 mW/cm ² for an adhesive resin in an adhesive film at 25 ° C The layer was irradiated with ultraviolet rays having a dominant wavelength of 365 nm at an ultraviolet ray of 1080 mJ/cm ² to photoharden the adhesive resin layer. Then, a static attenuation meter H-0110-S4 manufactured by SISH statics was used as a measuring device at a voltage of 10 kV and a distance between the sample and the electrode of 20 mm, 25 ° C, and 50% RH. Under the conditions, a voltage was applied to the surface of the adhesive resin layer for 30 seconds, and the half-life of the saturated electrostatic voltage (V ₁ ) and the saturated electrostatic voltage V ₁ on the surface of the adhesive resin layer was calculated in accordance with JIS L1094. Further, in addition to changing the amount of ultraviolet rays to 200 mJ/cm ² to 540 mJ/cm ² , the saturated electrostatic voltage of the surface of the adhesive resin layer was measured in the same order as the measurement of the saturated electrostatic voltage (V ₁ ). And the half-life of the saturated electrostatic voltage.

(2) Measurement of adhesion force The adhesion of the surface of the adhesive resin layer was measured by adhering the adhesive resin layer of the adhesive film to a polyimide film (product name: Kapton 200H, Manufactured by Du Pont-Toray Co., Ltd., using a high-pressure mercury lamp at a substrate layer side of an adhesive film at an irradiation intensity of 100 mW/cm ² at an irradiation intensity of 1080 mJ/cm ² at 25 ° C. The ultraviolet light at a wavelength of 365 nm hardens the adhesive resin layer. Then, the polyimide film was peeled off from the adhesive film, and a probe adhesion tester ("Probe Viscosity Tester by TESTING MACHINES Inc.: Model 80-02-01") was used. As a measuring device, a probe having a diameter of 5 mm was brought into contact with the surface of the adhesive resin layer at a speed of 10 mm/sec, and after contact with a contact load of 0.98 N/cm ² for 10 seconds, the probe was probed at a speed of 10 mm/sec. The surface of the needle self-adhesive resin layer is peeled off in the vertical direction. In addition, the adhesion of the surface of the adhesive resin layer was measured in the same order as the measurement of the adhesion force, except that the amount of ultraviolet rays was changed from 200 mJ/cm ² to 540 mJ/cm ² .

(3) Evaluation of antistatic property The antistatic property of the adhesive film was evaluated in accordance with the following criteria. ◎: The saturated electrostatic voltage V ₁ is 1.0 kV or less ○: The saturated electrostatic voltage V ₁ exceeds 1.0 kV and is 2.0 kV or less ×: The saturated electrostatic voltage V ₁ exceeds 2.0 kV

(4) Evaluation of Adhesion to Semiconductor Wafer Surface The adhesion to the surface of the semiconductor wafer was evaluated in accordance with the following criteria. ○: The adhesive force of the adhesive resin layer which is not irradiated with ultraviolet rays (that is, the amount of ultraviolet rays is 0 mJ/cm ² ) is 10 N/cm ² or more × The adhesive force of the adhesive resin layer which is not irradiated with ultraviolet rays is less than 10 N/cm ²

(5) Evaluation of the contamination resistance of the surface of the semiconductor wafer The contamination resistance of the surface of the semiconductor wafer was evaluated according to the following criteria. ○: Adhesion force of the adhesive resin layer which is light-cured by irradiation with an ultraviolet amount of 1080 mJ/cm ² is 0.1 N/cm ² or less ×: adhesion of an adhesive resin layer which is photocured by irradiation with an ultraviolet amount of 1080 mJ/cm ² Force exceeds 0.1 N/cm ²

(6) Evaluation of Concavity and Concavity Absorbance ○: When attached to the bump electrode forming surface of the semiconductor wafer having the bump electrode, the bump electrode is not broken, and the adhesion to the semiconductor wafer is good ×: attached When the bump electrode formation surface of the semiconductor wafer having the bump electrode is used, the bump electrode is broken or the adhesion to the semiconductor wafer is poor. The bump density is 80 μm and the bump pitch 300 is used for evaluation. A bump-attached semiconductor wafer having a bump of 150 μm in diameter and a bump of 150 μm. For the adhesion of the adhesive film, a roll laminator (product name: DR3000II manufactured by Nitto Seiki Co., Ltd.) was used at a roll speed of 2 mm/sec. The pressure was 0.4 MPa and the table temperature was 80 ° C, and the unevenness absorbability after the attachment was evaluated using an optical microscope.

[Table 1]

The adhesive films of Examples 1 to 3 are excellent in the balance between the adhesion to the surface of the semiconductor wafer and the stain resistance, and are excellent in antistatic property. The adhesive films of Examples 1 to 3 include the base in this order. a material layer, an antistatic layer, and an adhesive resin layer, and the adhesive resin layer contains an ion conductive additive. In other words, the adhesive film 100 for semiconductor wafer processing according to the present embodiment is understood to have excellent antistatic property after ultraviolet curing, and can suppress the amount of static electricity generated when peeling from the semiconductor wafer, and can stably obtain quality. Excellent semiconductor parts. On the other hand, the adhesive film of Comparative Example 1 to Comparative Example 3 in which the adhesive resin layer did not contain the ion conductive additive, and the adhesive film of Comparative Example 3 and Comparative Example 4 which did not include the antistatic layer were inferior in antistatic property.

The present application claims priority to Japanese Patent Application No. 2016-130822, filed on Jun.

10‧‧‧Substrate layer
20‧‧‧Concave-absorbent resin layer
30‧‧‧Antistatic layer
40‧‧‧Adhesive resin layer
100‧‧‧Adhesive film for semiconductor wafer processing (adhesive film)

The objectives and other objects, features and advantages of the invention will be apparent from the appended claims appended claims

FIG. 1 is a cross-sectional view showing an example of a structure of an adhesive film for semiconductor wafer processing according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an example of a configuration of an adhesive film for semiconductor wafer processing according to an embodiment of the present invention.

10‧‧‧Substrate layer

30‧‧‧Antistatic layer

40‧‧‧Adhesive resin layer

100‧‧‧Adhesive film for semiconductor wafer processing (adhesive film)

Claims (10)

An adhesive film for processing a semiconductor wafer, which is an adhesive film for protecting a surface of a semiconductor wafer or fixing a semiconductor wafer, and sequentially includes a substrate layer, an antistatic layer, and an adhesive resin layer, the adhesion The resin layer contains an ion conductive additive. The adhesive film for semiconductor wafer processing according to claim 1, wherein the adhesive resin layer contains an ultraviolet curable adhesive resin. The adhesive film for processing a semiconductor wafer according to the second aspect of the invention, wherein the content of the ion conductive additive in the adhesive resin layer is 100 parts by mass based on 100 parts by mass of the ultraviolet curable adhesive resin. It is 0.01 parts by mass or more and 10 parts by mass or less. The adhesive film for semiconductor wafer processing according to claim 1 or 2, wherein the ion conductive additive comprises a surfactant selected from the group consisting of a cationic surfactant, an anionic surfactant, and a nonionic interface. One or more of a dose, an amphoteric surfactant, and an ionic liquid. The adhesive film for semiconductor wafer processing according to the first or second aspect of the invention, wherein the thickness of the adhesive resin layer is 5 μm or more and 550 μm or less. An adhesive film for processing a semiconductor wafer according to the first or second aspect of the invention, which is a back-grinding tape. The adhesive film for processing a semiconductor wafer according to the first or second aspect of the invention, wherein the antistatic layer comprises a conductive polymer. The adhesive film for processing a semiconductor wafer according to the first or second aspect of the invention, further comprising an uneven-absorbent resin layer between the base material layer and the antistatic layer. The adhesive film for processing a semiconductor wafer according to the first or second aspect of the invention, wherein the surface of the adhesive resin layer after ultraviolet curing is measured by the following method, and the saturated electrostatic voltage V ₁ is 1.0 kV or less. (Method) The adhesive resin layer was irradiated with ultraviolet rays having a UV wavelength of 1080 mJ/cm ² at a dominant wavelength of 365 nm at an irradiation intensity of 100 mW/cm ² in an environment of 25 ° C to make the adhesion. The resin layer is photohardened; then, a voltage is applied to the surface of the adhesive resin layer for 30 seconds under the conditions of a voltage of 10 kV and a distance between the sample and the electrode of 20 mm, 25 ° C, and 50% RH, according to Japanese Industrial Standards. L1094 calculates the saturated electrostatic voltage (V ₁ ) of the surface of the adhesive resin layer. The adhesive film for processing a semiconductor wafer according to the first or second aspect of the invention, wherein the adhesion of the surface of the adhesive resin layer after ultraviolet curing measured by the following method is 0.1 N/cm ² (Method) The adhesion of the surface of the adhesive resin layer is measured by bonding the adhesive resin layer of the adhesive film to a polyimide film at 25 ° C, since the base layer of the adhesive film side using a high pressure mercury lamp at an irradiation intensity of 100 mW / cm ² irradiation amount of the ultraviolet ray 1080 mJ / cm ² of 365 nm dominant wavelength ultraviolet, so that the adhesive resin layer photohardening Then, the polyimide film was peeled off from the adhesive film, and a probe having a diameter of 5 mm and a surface of the adhesive resin layer were set to 10 mm/ using a probe adhesion tester as a measuring device. At a speed contact of ^two seconds, after contact with a contact load of 0.98 N/cm ² for 10 seconds, the probe was peeled off from the surface of the adhesive resin layer in a vertical direction at a speed of 10 mm/sec.