TWI733847B - 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 semiconductor wafer processing.

In the manufacturing process of the semiconductor device, in the step of grinding or cutting the semiconductor wafer, in order to fix the semiconductor wafer or prevent damage to the semiconductor wafer, an adhesive film is attached to 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. The adhesive film is irradiated with ultraviolet rays, the adhesive resin layer is cross-linked and the adhesive force of the adhesive resin layer is reduced, so the adhesive film can be easily peeled from the semiconductor wafer.

On the other hand, in the manufacturing process of a semiconductor device using such an adhesive film, when the adhesive film is peeled from the semiconductor wafer, static electricity called peeling static electricity may be generated. Due to the static electricity generated in this way, there are cases where the circuit formed on the semiconductor wafer is destroyed (electrostatic destruction), or foreign matter such as dust adheres to the circuit formed on the semiconductor wafer.

In particular, with the recent increase in density of semiconductor wafers. With the narrowing of the wiring pitch, semiconductor wafers tend to be more susceptible to static electricity than before.

In view of the foregoing, in recent years, the manufacturing steps for semiconductor devices Adhesive films used to fix semiconductor wafers or prevent damage to semiconductor wafers also require further enhancement of antistatic performance.

As a technique related to such an adhesive film for semiconductor wafer processing, the one described in Patent Document 1 (Japanese Patent Laid-Open No. 2011-210944) can be cited, for example.

Patent Document 1 describes an antistatic adhesive tape for semiconductor processing, which is an adhesive tape including a base film and a photocurable adhesive layer. The antistatic adhesive tape for semiconductor processing is characterized by At least one surface of the base film has an antistatic layer containing a conductive polymer, and on the antistatic layer there is an adhesive layer containing a photocurable unsaturated carbon bond in the molecule of the base polymer, which is cured by ultraviolet light The surface resistivity of the adhesive layer side before and after is 1×10 ⁶ Ω/□~5×10 ¹² Ω/□, and the thickness of the adhesive layer is 20 μm to 250 μm. When the adhesive tape is attached to the silicon mirror wafer The 90-degree peel adhesion strength of the adhesive layer after ultraviolet curing (according to Japanese Industrial Standards (JIS) Z0237; peeling speed is 50mm/min) is 0.15N/25mm~0.25N/25mm.

[Prior Art Literature] [Patent Literature]

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

As described in the aforementioned item of the prior art, in recent years, the technical level required for countermeasures against static electricity of adhesive films for semiconductor wafer processing has gradually increased.

According to research conducted by the inventors of the present invention, it has been clarified that the adhesive film in which a base film, an antistatic layer, and an adhesive layer are sequentially laminated as described in Patent Document 1 does not sufficiently satisfy antistatic properties.

More specifically, it has been clarified that with regard to the adhesive film as described in Patent Document 1, the saturated electrostatic voltage of the adhesive layer is greatly increased after ultraviolet curing, and the antistatic property is seriously deteriorated.

The present invention is made in view of the above circumstances, and provides an adhesive film for semiconductor wafer processing, which has excellent antistatic properties after ultraviolet curing, and can suppress the amount of static electricity generated when peeling from the semiconductor wafer, and can stably Obtain high-quality semiconductor parts.

The inventors of the present invention have repeatedly and diligently studied in order to achieve the above-mentioned problem. As a result, it was found that for an adhesive film that includes a substrate layer, an antistatic layer, and an adhesive resin layer in this order, by adding an ion conductive additive to the adhesive resin layer, the saturated static electricity of the adhesive film after UV curing can be suppressed. The voltage rises, thus completing the present invention.

According to the present invention, the following adhesive film for semiconductor wafer processing can be provided.

[1]

An adhesive film for semiconductor wafer processing, which is an adhesive film used to protect the surface of a semiconductor wafer or fix the semiconductor wafer, and sequentially includes a substrate layer, an antistatic layer, and an adhesive resin layer. The sexual resin layer contains an ion conductive additive.

[2]

The adhesive film for semiconductor wafer processing as described in [1], wherein the adhesive resin layer contains an ultraviolet curable adhesive resin.

[3]

The adhesive film for semiconductor wafer processing as described in [2], wherein the content of the ion conductive additive in the adhesive resin layer is relative to 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.

[4]

The adhesive film for semiconductor wafer processing according to any one of [1] to [3], wherein the ion conductive additive includes a cationic surfactant, an anionic surfactant, and a nonionic surfactant. One or more than two types of surfactants, amphoteric surfactants and ionic liquids.

[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 as described in 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 includes a conductive polymer.

[8]

The adhesive film for semiconductor wafer processing according to any one of [1] to [7], which further includes a concavo-convex absorptive resin layer between the base layer and the antistatic layer.

[9]

The adhesive film for semiconductor wafer processing according to any one of [1] to [8], wherein the saturated electrostatic voltage V _{1 on the} surface of the adhesive resin layer after ultraviolet curing measured by the following method is Below 1.0kV.

(method)

Under an environment of 25° C., a high-pressure mercury lamp was used to irradiate the adhesive resin layer with an ultraviolet amount of 1080 mJ/cm ^{2 of ultraviolet rays with a dominant wavelength of 365 nm at an irradiation intensity of 100 mW/cm 2} to light-harden the adhesive resin layer. Then, a voltage was applied to the surface of the adhesive resin layer for 30 seconds under the conditions of an applied voltage of 10 kV, a distance between the sample and the electrode of 20 mm, 25° C., and 50% RH, and the pressure of the adhesive resin layer was calculated in accordance with JIS L1094. Saturated electrostatic voltage on the surface (V ₁ ).

[10]

The adhesive film for semiconductor wafer processing according to any one of [1] to [9], wherein the adhesive force of the surface of the adhesive resin layer after ultraviolet curing measured by the following method is 0.1 N /cm ² or less.

(method)

The adhesive force of the surface of the adhesive resin layer was measured by the following method: the adhesive resin layer of the adhesive film was attached to a polyimide film, and the adhesiveness was measured at 25°C. A high-pressure mercury lamp was used on the base layer side of the film to irradiate ultraviolet rays with a dominant wavelength of 365 nm with an ultraviolet amount of 1080 mJ/cm ^{2 at an irradiation intensity of 100 mW/cm 2 to light-harden the adhesive resin layer.} Then, the polyimide film was peeled off from the adhesive film, and a probe tack tester was used as a measuring device to make a probe with a diameter of 5 mm and the surface of the adhesive resin layer to The probe was contacted at a speed of 10 mm/sec. After contacting at ^{a contact load of 0.98 N/cm 2} for 10 seconds, the probe was peeled off the surface of the adhesive resin layer in a vertical direction at a speed of 10 mm/sec.

According to the present invention, it is possible to provide an adhesive film for semiconductor wafer processing, which has excellent antistatic properties after ultraviolet curing, and can suppress the amount of static electricity generated when peeling from the semiconductor wafer, and can stably obtain semiconductor parts with excellent quality .

10: Substrate layer

20: Concave-convex absorbent resin layer

30: Antistatic layer

40: Adhesive resin layer

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

The objective and other objectives, features and advantages are further clarified by the preferred embodiments described below and the accompanying drawings.

FIG. 1 is a schematic view of a semiconductor wafer processing device according to an embodiment of the present invention. A cross-sectional view of an example of the structure of an adhesive film for industrial use.

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

Hereinafter, embodiments of the present invention will be described using drawings. In addition, in all the drawings, common symbols are attached to the same constituent elements, and descriptions are appropriately omitted. In addition, the figure is a schematic diagram and does not match the actual size ratio. In addition, "A~B" in the numerical range means A to B or more unless otherwise specified. In addition, in this embodiment, the term "(meth)acrylic acid" refers to acrylic acid, methacrylic acid, or both acrylic acid and methacrylic acid.

1 and 2 are cross-sectional views schematically showing an example of the structure of the adhesive film 100 for semiconductor wafer processing according to the 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 this embodiment includes a base 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. Furthermore, the adhesive resin layer 40 contains an ion conductive additive.

As mentioned above, in recent years, the level of technology required for countermeasures against static electricity of adhesive films for semiconductor wafer processing has gradually increased. In particular, in the case of semiconductor wafers with bump electrodes such as solder bumps or copper pillar bumps formed on high-density circuits used in semiconductor wafers equipped with high-density circuits, there may be static electricity. This tends to cause damage (short-circuit) of the circuit including the bump electrode formed on the semiconductor wafer, so this requirement is even more significant.

Therefore, it is desired to realize an adhesive film for semiconductor wafer processing with more excellent antistatic properties.

Here, according to the research of the inventors of the present invention, it has been clarified that the adhesive film in which a base film, an antistatic layer, and an adhesive layer are sequentially laminated as described in Patent Document 1 does not sufficiently satisfy antistatic properties.

More specifically, it has been clarified that with regard to the adhesive film as described in Patent Document 1, the saturated electrostatic voltage of the adhesive layer is greatly increased after ultraviolet curing, and the antistatic property is seriously deteriorated.

The inventors of the present invention have repeatedly and diligently studied in order to achieve the above-mentioned problem. As a result, it was discovered for the first time that for an adhesive film consisting of a substrate layer, an antistatic layer, and an adhesive resin layer in sequence, by adding ion conductive additives to the adhesive resin layer, the saturation of the adhesive film after UV curing can be suppressed The rise of electrostatic voltage.

That is, the adhesive film 100 for semiconductor wafer processing of the present embodiment is composed of the above-mentioned layer, and has excellent antistatic properties after ultraviolet curing, can suppress the amount of static electricity generated when peeling from the semiconductor wafer, and can Stably obtain high-quality semiconductor parts.

Regarding the adhesive film 100 of the present embodiment, the saturated electrostatic voltage V1 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)

Under an environment of 25° C., a high-pressure mercury lamp was used to irradiate the adhesive resin layer 40 with an ultraviolet amount of 1080 mJ/cm ^{2 of ultraviolet rays with a dominant wavelength of 365 nm at an irradiation intensity of 100 mW/cm 2} to light-harden the adhesive resin layer 40. Then, a voltage was applied to the surface of the adhesive resin layer 40 for 30 seconds under the conditions of an applied voltage of 10 kV, a distance between the sample and the electrode 20 mm, 25° C., and 50% RH. The surface of the adhesive resin layer 40 was calculated according to JIS L1094. Saturation electrostatic voltage (V ₁ ).

_{By setting the saturated electrostatic voltage V 1} of the adhesive resin layer 40 after ultraviolet curing to be equal to or less than the upper limit, the antistatic property to 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 this embodiment, for example, by appropriately adjusting the types or blending ratios of the components constituting the adhesive resin layer 40, the thickness of the adhesive resin layer 40, etc., the saturated electrostatic voltage of the adhesive resin layer 40 after ultraviolet curing can be adjusted. V _{1 is} controlled to be equal to or less than the upper limit.

Among these, for example, the presence or absence of ion-conducting additives in the adhesive resin layer 40, or the thickness of the adhesive resin layer 40, etc. can be cited as the saturated electrostatic voltage V ₁ for the adhesive resin layer 40 after ultraviolet curing. Elements requiring a range of values.

For example, if 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 thinner, the saturated electrostatic voltage V ₁ can be reduced.

Regarding the adhesive film 100 of this embodiment, when the saturated electrostatic voltage of the surface of the adhesive resin layer 40 after ultraviolet curing measured by the following method is set to V ₂ , V ₁ /V _{2 is} preferably 5.0 or less, and more It is preferably 3.0 or less, and more preferably 2.5 or less. If V ₁ /V ₂ is less than or equal to the above upper limit, the amount of static electricity generated when peeling from the semiconductor wafer can be suppressed more stably, and semiconductor components of excellent quality can be obtained more stably.

(method)

In an environment of 25° C., a high-pressure mercury lamp was used to irradiate the adhesive resin layer 40 with an ultraviolet amount of 200 mJ/cm ^{2 of ultraviolet light with a dominant wavelength of 365 nm at an irradiation intensity of 100 mW/cm 2} to light-harden the adhesive resin layer 40. Then, a voltage was applied to the surface of the adhesive resin layer 40 for 30 seconds under the conditions of an applied voltage of 10 kV, a distance between the sample and the electrode 20 mm, 25° C., and 50% RH. The surface of the adhesive resin layer 40 was calculated according to JIS L1094. Saturation electrostatic voltage (V ₂ ).

Regarding 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, particularly preferably It is less than 1 second.

Here, the half-life of the saturated electrostatic voltage V ₁ refers to the time that the value of the electrostatic voltage decreases to half after the completion of the voltage application to the surface of the adhesive resin layer 40 in the measurement of the _{saturated electrostatic voltage V 1.}

Regarding the adhesive film 100 of this embodiment, the saturated electrostatic voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing is below the upper limit, so such a short half-life can be achieved, and it can be made with excellent antistatic properties. The adhesive film 100.

Adhesion surface 100, the following method of measuring the UV resin adhesive layer 40 after curing adhesive film according to the present embodiment is about ² or less is preferably 0.1N / cm, more preferably ² or less 0.05N / cm, and further It is preferably 0.01 N/cm ² or less.

When the adhesive force of the surface of the adhesive resin layer 40 cured by ultraviolet rays is below the upper limit, it is easier to peel the adhesive film 100 from the surface of the semiconductor wafer, and a part of the adhesive resin layer 40 can be further suppressed 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 adhesive force 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 attached to a polyimide film (product name: Kapton 200H, Toray DuPont ( Du Pont-Toray), in an environment of 25°C, from the base layer 10 side of the adhesive film 100, a high-pressure mercury lamp is used to irradiate the intensity of 100mW/cm ^{2 to} irradiate the ultraviolet rays with the main wavelength of 365nm of ^{1080mJ/cm 2} , And the adhesive resin layer 40 is photocured. Then, the polyimide film is peeled off from the adhesive film 100, and a probe tack tester (for example, a probe tack tester manufactured by TESTING MACHINES Inc.: model 80- 02-01") As a measuring device, a probe with 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. After contacting with a contact load of ^{0.98 N/cm 2 for 10 seconds, a probe with a diameter of 10 mm/sec} The speed peels the probe from the surface of the adhesive resin layer 40 in the vertical direction.

In terms of the balance between mechanical properties and operability, 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.

The adhesive film 100 of this embodiment is used to protect the surface of the semiconductor wafer or to fix the semiconductor wafer in the manufacturing step of the semiconductor device, more specifically, In other words, it is preferably used as a back grind tape for protecting the circuit formation surface (ie, the circuit surface including the circuit pattern) of the semiconductor wafer in the back grind step, which is one of the manufacturing steps of the semiconductor device.

Here, when the semiconductor wafer to be attached is a semiconductor wafer on which a circuit including a micro wiring including bump electrodes is applied on the surface, it is likely to be caused by static electricity generated when the adhesive film is peeled from the semiconductor wafer The circuit formed on the semiconductor wafer is broken, that is, electrostatic breakdown, etc., but by using the adhesive film 100 of this embodiment, even for such a semiconductor wafer with bump electrodes formed on the surface, it is possible to more reliably suppress Electrostatic damage, etc.

The semiconductor wafer to which the adhesive film 100 of this embodiment can be applied is not particularly limited, and a silicon wafer or the like can be mentioned.

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

(Substrate layer)

The base material layer 10 is a layer provided for the purpose of improving the handling properties, 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 that can withstand external force applied when processing a semiconductor wafer, and for example, a resin film can be mentioned.

As the resin constituting the resin film, a known thermoplastic resin can be used. For example, one or two or more selected from the following compounds: polyethylene, polypropylene, poly(4-methyl-1-pentene), poly(1-butene) and other polyolefins; polyterephthalic acid Polyesters such as ethylene glycol and polybutylene terephthalate; nylon-6, nylon-66, polyhexamethylene isophthalate Polyamides such as methylamine; polyacrylates; polymethacrylates; polyvinyl chloride; polyether imines; ethylene. Vinyl acetate copolymer; polyacrylonitrile; polycarbonate; polystyrene; ionic polymer;

Among these, from the viewpoint of semiconductor wafer protection, it is preferably selected from polypropylene, polyethylene terephthalate, polyamide, and ethylene. One or two or more of the vinyl acetate copolymers, more preferably selected from polyethylene terephthalate and ethylene. One or two or more of vinyl acetate copolymers.

The base material layer 10 may be a single layer, or two or more layers.

In addition, the form of the resin film used for forming the base layer 10 may be a stretched film, or a film stretched in a uniaxial direction or a biaxial direction, but from the viewpoint of improving the mechanical strength of the base layer 10 In particular, it is preferably a film extending in a uniaxial direction or a biaxial direction.

From the viewpoint of obtaining good film characteristics, the thickness of the base 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 still more preferably 25 μm or more and 150 μm or less.

In order to improve the adhesion with other layers, the base layer 10 may be subjected to surface treatment. Specifically, corona treatment, plasma treatment, under coat treatment, primer coat treatment, etc. may also be performed.

(Adhesive resin layer)

The adhesive film 100 of this embodiment includes an adhesive resin layer 40.

The adhesive resin layer 40 is a layer that contacts 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 (meth)acrylic adhesives, silicone adhesives, and urethane adhesives.

The (meth)acrylic adhesive contains a (meth)acrylic adhesive resin which is an ultraviolet curable adhesive resin as an essential component. The silicone adhesive contains as an essential component a silicone adhesive resin which is an ultraviolet curable adhesive resin. The urethane-based adhesive contains, as an essential component, a urethane-based adhesive resin which is an ultraviolet-curable adhesive resin.

Among these, from the viewpoint of easy adjustment of adhesive force, etc., a (meth)acrylic adhesive is preferable.

As the (meth)acrylic adhesives, the following adhesives can be exemplified: (meth)acrylic adhesives containing polymerizable carbon-carbon double bonds in the molecule, and two or more polymerizable carbons in the molecule. The low-molecular-weight compound of the carbon double bond and the photoinitiator are obtained by crosslinking the (meth)acrylic adhesive resin with a crosslinking agent as necessary.

The (meth)acrylic adhesive resin having a polymerizable carbon-carbon double bond in the molecule can be specifically obtained as follows. First, a monomer having an ethylenic double bond and a copolymerizable monomer having a functional group (P) are copolymerized. Then, the functional group (P) contained in the copolymer and a monomer having a functional group (Q) capable of causing an addition reaction, a condensation reaction, etc., with the functional group (P) are combined in the monomer. The reaction proceeds with the bond remaining, and the 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 of the following compounds are used: methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and (meth)acrylic acid Alkyl acrylate and (meth)acrylate monomers such as butyl ester and ethyl (meth)acrylate, vinyl esters such as vinyl acetate, (meth)acrylonitrile, (meth)acrylonitrile Monomers with ethylenic double bonds such as amine and styrene.

Examples of the copolymerizable monomer having a functional group (P) include (meth)acrylic acid, maleic acid, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, N-methylol (meth)acrylamide, (meth)acryloxyethyl isocyanate, etc. One of these may be used, or two or more of them may be used in combination. The ratio of the monomer having an ethylenic double bond to the copolymerizable monomer having a functional group (P) is preferably 70% to 99% by mass relative to the former, and 30% to 1% by mass in the latter. More preferably, the former is 80% to 95% by mass, and the latter is 20% to 5% by mass.

Examples of the monomer having the functional group (Q) include the same monomers as the copolymerizable monomer having the functional group (P).

As a functional group (P) and a functional group (Q The combination of) is preferably a combination that easily causes an addition reaction, such as a carboxyl group and an epoxy group, a carboxyl group and an aziridin group, a hydroxyl group and an isocyanate group. In addition, it is not limited to an addition reaction, and any reaction may be used as long as it is a reaction in which a polymerizable carbon-carbon double bond can be easily introduced, such as a condensation reaction of a carboxyl group and a hydroxyl group.

As a low molecule with more than two polymerizable carbon-carbon double bonds in the molecule The amount of compound includes: tripropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetraacrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol mono Hydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc. One or two or more of these can be used. With respect to 100 parts by mass of the (meth)acrylic adhesive resin, the addition amount of the low-molecular-weight compound having two or more polymerizable carbon-carbon double bonds in the molecule is preferably 0.1 parts by mass to 20 parts by mass, and more It is preferably 5 parts by mass to 18 parts by mass.

As the photoinitiator, benzoin, benzoin isopropyl ether, benzoin isobutyl ether, benzophenone, Michele ketone, chlorothioxanthone, lauryl thioxanthone, dimethyl sulfur can be cited. Heteroanthrone, diethylthioxanthone, acetophenone diethyl ketal, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-benzene Base propane-1-copper and so on. One or two or more of these can be used. Relative to 100 parts by mass of the (meth)acrylic adhesive resin, the addition amount of the photoinitiator is preferably 0.1 parts by mass to 15 parts by mass, more preferably 5 parts by mass to 10 parts by mass.

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 diglycerol polyglycidyl ether; tetramethylolmethane- Tri-β-aziridinyl propionate, trimethylolpropane-tri-β-aziridinyl propionate, N,N'-diphenylmethane-4,4'-bis(1-nitrogen Propidium carboxyamide), N,N'-hexamethylene-1,6-bis(1-aziridine carboxyamide) and other aziridine compounds; tetramethylene diisocyanate, hexamethylene Isocyanate compounds such as diisocyanate and polyisocyanate. The ultraviolet curable adhesive can be solvent type, emulsion type, thermal Any type of melting.

The content of the crosslinking agent is generally preferably in a range such that the number of functional groups in the crosslinking agent does not exceed the number of functional groups in the (meth)acrylic adhesive resin. However, in the case where a functional group is newly generated in the crosslinking reaction, or when the crosslinking reaction is slow, etc., the crosslinking agent may be contained too much as necessary.

From the viewpoint of improving the heat resistance of the adhesive resin layer 40 or the balance with the adhesive force, relative to 100 parts by mass of the (meth)acrylic adhesive resin, the amount of the crosslinking agent in the (meth)acrylic adhesive is The content is preferably 0.1 parts by mass or more and 15 parts by mass or less.

The adhesive resin layer 40 of this embodiment contains an ion conductive additive. Thereby, the antistatic property of the adhesive resin layer 40 can be improved. Furthermore, the increase in the saturation electrostatic voltage of the adhesive film 100 after ultraviolet curing can be suppressed.

Examples of ion conductive additives include cationic surfactants, anionic surfactants, nonionic surfactants, amphoteric surfactants, ionic liquids, and the like. From the viewpoint that the antistatic property of the adhesive resin layer 40 can be further improved, at least one selected from a cationic surfactant and an anionic surfactant is preferred, and a cationic surfactant is more preferred.

Examples of cationic surfactants include: dodecyltrimethylammonium chloride, tetradecyldimethylbenzylammonium chloride, cetyldimethylbenzylammonium chloride, stearyl Dimethyl benzyl ammonium chloride, tetradecyl trimethyl ammonium chloride, cetyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, di-dodecyl dimethyl ammonium chloride Ammonium chloride, di-tetradecyl dimethyl ammonium chloride, di-hexadecyl dimethyl ammonium chloride, two -Octadecyl dimethyl ammonium chloride, dodecyl benzyl dimethyl ammonium chloride, cetyl benzyl dimethyl ammonium chloride, octadecyl benzyl dimethyl ammonium chloride , Palmyl trimethyl ammonium chloride, oleyl trimethyl ammonium chloride, dipalmityl benzyl methyl ammonium chloride, dioleyl benzyl methyl ammonium chloride, etc.

As a cationic surfactant, a quaternary ammonium salt or an amine salt type is mentioned, Preferably it is a quaternary ammonium salt.

Among them, it is preferably at least one selected from the group consisting of tetradecyl dimethyl benzyl ammonium chloride, cetyl dimethyl benzyl ammonium chloride, and stearyl dimethyl benzyl ammonium chloride.

As an anionic surfactant, for example, diammonium dodecyl diphenyl ether disulfonate, sodium dodecyl diphenyl ether disulfonate, calcium dodecyl diphenyl ether disulfonate , Sodium alkyl diphenyl ether disulfonate and other alkyl diphenyl ether disulfonates; sodium dodecyl benzene sulfonate, ammonium dodecyl benzene sulfonate and other alkyl benzene sulfonates; lauryl Alkyl sulfate ester salts such as sodium sulfate and ammonium lauryl sulfate; aliphatic carboxylate salts such as fatty acid sodium and potassium oleate; sulfate ester salts containing polyoxyalkylene units (for example, polyoxyethylene alkyl ether sodium sulfate, Polyoxyethylene alkyl ether ammonium sulfate and other polyoxyethylene alkyl ether sulfates; polyoxyethylene alkyl phenyl ether sodium sulfate, polyoxyethylene alkyl phenyl ether ammonium sulfate and other polyoxyethylene alkyl phenyl ether sulfates Ester salt; polyoxyethylene polycyclic phenyl ether sodium sulfate, polyoxyethylene polycyclic phenyl ether ammonium sulfate and other polyoxyethylene polycyclic phenyl ether sulfate ester salts, etc.); naphthalenesulfonic acid such as sodium naphthalenesulfonic acid formaldehyde condensate Formaldehyde condensate salt; sodium dialkyl sulfosuccinate, disodium monoalkyl sulfosuccinate and other alkyl sulfosuccinates; polyoxyethylene-polyoxypropylene glycol ether sulfate; sulfonates or molecules Surfactant having a sulfate group and a polymerizable carbon-carbon (unsaturated) double bond, etc.

Examples of nonionic surfactants include polyoxyalkylene alkylene such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene tridecyl ether, and polyoxyethylene oleyl ether. Based ether compounds, polyoxyalkylene alkyl phenyl ether compounds such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether, polyoxyalkylene polycyclics such as polyoxyethylene polycyclic phenyl ether Ether compounds containing polyoxyalkylene units such as phenyl ether compounds; polyoxyalkylene alkyl ester compounds such as polyoxyethylene monolaurate, polyoxyethylene monostearate, and polyoxyethylene monooleate ; Polyoxyethylene alkylamine and other polyoxyalkylene alkylamine compounds; sorbitan monolaurate, sorbitan monostearate, sorbitan trioleate, polyoxyethylene Sorbitan compounds such as sorbitan monolaurate and polyoxyethylene sorbitan monooleate.

As an amphoteric surfactant, lauryl betaine, lauryl dimethyl amine oxide, etc. are mentioned.

These ion conductive additives may be used singly, or two or more of them may be used in combination.

Relative to 100 parts by mass of the ultraviolet curable adhesive resin, the content of the ion conductive additive in the adhesive resin layer 40 is preferably 0.01 part 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 , More preferably, it is 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 on the antistatic layer 30.

As a method of applying the adhesive coating liquid, a previously known coating method can be used, such as roll coater method, reverse roll coater method, gravure roll method, bar coating method, Missing wheel coater method, die coater method, etc. The drying conditions of the applied adhesive are not particularly limited, and it is generally preferable to dry in a temperature range of 80°C to 200°C for 10 seconds to 10 minutes. It is more preferable to dry at 80°C to 170°C for 15 seconds to 5 minutes. In order to fully promote the cross-linking reaction between the cross-linking agent and the (meth)acrylic adhesive resin, the adhesive coating solution may be heated at 40°C to 80°C for about 5 hours to 300 hours after drying.

In the adhesive film 100 of this 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, more preferably 30 μm or more and 300 μm or less, and particularly preferably 50 μm or more and 250 μm. the following. If the thickness of the adhesive resin layer 40 is within the above-mentioned range, the adhesiveness to the surface of the semiconductor wafer and handleability are well balanced.

In addition, when the adhesive film 100 of the present embodiment further includes the concave-convex absorbent resin layer 20 described later, the thickness of the adhesive resin layer 40 is preferably 100 μm or less, more preferably 50 μm or less, and still more preferably less than 30 μm It is still more preferably 25 μm or less, still more preferably less than 20 μm, 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 made better. In addition, in the case where the adhesive film 100 of the present embodiment further includes the concave-convex absorbent resin layer 20 described later, the lower limit of the thickness of the adhesive resin layer 40 is not particularly limited, but from the viewpoint of making the adhesive force good In other words, it is preferably 0.5 μm or more, more preferably 1.0 μm or more, still more preferably 3.0 μm or more, and particularly preferably 5.0 μm or more.

(Antistatic layer)

The adhesive film 100 of this embodiment includes an antistatic layer 30. Thereby, the antistatic property of the adhesive film 100 can be improved while the adhesiveness of the adhesive film 100 is maintained, and the amount of static electricity generated when the adhesive film 100 is peeled from the semiconductor wafer can be suppressed.

From the viewpoint of reducing the surface resistance value of the antistatic layer 30 and suppressing the generation of static electricity accompanying peeling, the material constituting the antistatic layer 30 preferably contains a conductive polymer.

Examples of conductive polymers include: polythiophene-based conductive polymers, polypyrrole-based conductive polymers, polyaniline-based conductive polymers, poly(paraphenylene vinylene)-based conductive polymers, and Quinoxaline-based conductive polymers, etc.

From the viewpoint of a good balance between optical properties and appearance, antistatic properties, coating properties, stability, etc., a polythiophene-based conductive polymer is preferred. Examples of polythiophene-based conductive polymers include polyethylene dioxythiophene and polythiophene.

These conductive polymers may be used singly, or two or more of them may be used in combination.

The material forming the antistatic layer 30 may further include a doping agent, a binder resin, and the like, for example.

The dopant functions as a dopant, and more reliably imparts (doping) conductivity to the conductive polymer, and examples thereof include sulfonic acid-based compounds.

Examples of sulfonic acid compounds include p-toluenesulfonic acid, benzenesulfonic acid, ethylbenzenesulfonic acid, octylbenzenesulfonic acid, dodecylbenzenesulfonic acid, mesitylenesulfonic acid, m-xylenesulfonic acid, poly Styrene sulfonic acid, polyvinyl sulfonic acid, etc. From the viewpoint of improving the solubility or water dispersibility of the conductive polymer, polystyrene sulfonic acid or polyethylene is preferred Sulfonic acid.

A sulfonic acid compound may be used individually by 1 type, and may be used in combination of 2 or more types.

By adding such a dopant, a part of the conductive polymer reacts with the sulfonic acid compound to form a sulfonate, and the antistatic function of the antistatic layer 30 is further improved by the action of the sulfonate.

The blending ratio of the dopant is, for example, 100 parts by mass to 300 parts by mass with respect to 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 of its superior antistatic properties.

From the viewpoint of improving film forming properties, adhesiveness, and the like, the material constituting the antistatic layer 30 may further include a binder resin.

Examples of binder resins include polyurethane resins, polyester resins, (meth)acrylic resins, polyether resins, cellulose resins, polyvinyl alcohol resins, and epoxy resins. , Polyvinylpyrrolidone, polystyrene resin, polyethylene glycol, pentaerythritol, etc.

One kind of binder resin may be used alone, or two or more kinds may be used in combination. The content of the binder resin is, for example, 10 parts by mass to 500 parts by mass with respect to 100 parts by mass of the conductive polymer.

From the viewpoint of antistatic performance, 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, More preferably, it is 0.01 μm or more and 1 μm or less.

(Concave-convex absorbent resin layer)

As shown in FIG. 2, the adhesive film 100 of this embodiment preferably further includes a concave-convex absorbent resin layer 20 between the base layer 10 and the antistatic layer 30.

Thereby, the thickness of the adhesive resin layer 40 can be reduced while the unevenness of the adhesive film 100 is good, 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 viewpoint of mechanical strength and conformability balance irregularities, the density unevenness absorbing resin layer 20 is preferably from ^{800kg / m 3 ~ 990kg / m} 3, more preferably from ^{830kg / m 3 ~ 980kg / m} 3, and further good It is 850kg/m ³ ~970kg/m ³ .

The resin constituting the concavo-convex absorbent resin layer 20 is not particularly limited as long as it exhibits concavo-convex absorbency, and for example, a thermoplastic resin can be used.

More specifically, it can include: olefin resin, ethylene. Polar monomer copolymer, acrylonitrile. Butadiene. Acrylonitrile Butadiene Styrene (ABS) resin, vinyl chloride resin, vinylidene chloride resin, (meth)acrylic resin, polyamide resin, fluorine resin, polycarbonate resin, polyester resin, etc. .

Among these, it is preferably selected from olefin-based resins and ethylene. At least one of the polar monomer copolymers.

Examples of olefin resins include linear low density polyethylene (LLDPE), low density polyethylene, high density polyethylene, polypropylene, ethylene and α-olefins having 3 to 12 carbon atoms. The ethylene. α-ene Hydrocarbon copolymers, propylene containing propylene and α-olefins with 4 to 12 carbon atoms. α-olefin copolymer, ethylene. Cyclic olefin copolymer, ethylene. Alpha-olefin. Cyclic olefin copolymers, etc.

As ethylene. Polar monomer copolymers, such as ethylene. (Meth) ethyl acrylate copolymer, ethylene. (Meth) methyl acrylate copolymer, ethylene. (Meth) Propyl acrylate copolymer, ethylene. (Meth) butyl acrylate copolymer and other ethylene. Unsaturated carboxylic acid ester copolymer; ethylene. Vinyl acetate copolymer, ethylene. Vinyl propionate copolymer, ethylene. Vinyl butyrate copolymer, ethylene. Vinyl stearate copolymer and other ethylene. Vinyl ester copolymers, etc.

The resin constituting the concavo-convex absorbent resin layer 20 may be used alone, or two or more types may be used in a blend (blend).

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

Among these, in terms of excellent concavity and convexity followability at the time of attachment, it is preferably at least one selected from the following compounds: low-density polyethylene; polypropylene; ethylene. Propylene copolymer, ethylene. 1-Butene copolymer, ethylene. Propylene. Ethylene such as terpolymers of α-olefins with 4 to 12 carbon atoms. α-olefin copolymer; propylene. 1-Butene. Terpolymer of α-olefins with 5 to 12 carbon atoms; ethylene. Vinyl acetate copolymer, etc., more preferably selected from ethylene. Propylene copolymer and ethylene. At least one of vinyl acetate copolymers.

The thickness of the concavity and convexity absorptive resin layer 20 is not particularly limited as long as it can be embedded in the concavity and convexity of the concavity and convexity forming surface of the semiconductor wafer. For example, it is preferably 10 μm. Above and 500 μm or less, more preferably 20 μm or more and 400 μm or less, still 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 this embodiment, an adhesive layer (not shown) may be provided between each layer. With the adhesive layer, the adhesiveness between the layers can be improved.

In addition, the adhesive film 100 of this embodiment may further laminate a release film.

Next, an example of the manufacturing method of the adhesive film 100 for semiconductor wafer processing of this embodiment is demonstrated.

First, on one surface of the base layer 10, the concavo-convex absorbent resin layer 20 is formed by the extrusion lamination method. Then, a predetermined conductive material is coated on a separately prepared release film and dried to form an antistatic layer 30, and the antistatic layer 30 is laminated on the concavo-convex absorbent resin layer 20. Then, the adhesive coating liquid is coated on the antistatic layer 30 and dried, thereby forming the adhesive resin layer 40, thereby obtaining the adhesive film 100.

In addition, the base material layer 10 and the concavo-convex absorbent resin layer 20 may be formed by coextrusion molding, or the film-shaped base material layer 10 and the film-shaped concavo-convex absorbent resin layer 20 may be laminated (laminated). form.

Next, an example of the back surface grinding method (also referred to as back surface grinding) of a semiconductor wafer using the adhesive film 100 for semiconductor wafer processing of this embodiment is demonstrated. The back surface grinding method of a semiconductor wafer of this embodiment is characterized by using the adhesive film 100 for semiconductor wafer processing of this embodiment as a back surface polishing tape when grinding the back surface of a semiconductor wafer.

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 forming 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 a grinder via the base layer 10 of the adhesive film 100, and the back surface (circuit non-forming surface) of the semiconductor wafer is ground. After the grinding is completed, the adhesive film 100 is peeled off. In some cases, after the grinding of the back surface of the semiconductor wafer is completed, and before the adhesive film 100 is peeled off, a chemical etching step is performed. In addition, after the adhesive film 100 is peeled off, if necessary, treatments such as water washing and plasma washing are performed on the back surface of the semiconductor wafer.

In such a back surface grinding operation, the thickness of the semiconductor wafer before grinding is usually 500 μm to 1000 μm. In contrast, the thickness of the semiconductor wafer before grinding is usually about 100 μm to 600 μm depending on the type of semiconductor wafer. If necessary, it is sometimes cut to be thinner than 100μm. The thickness of the semiconductor wafer before grinding is appropriately determined by the diameter and type of the semiconductor wafer, and the thickness of the wafer after grinding is appropriately determined by the size of the obtained wafer, the type of circuit, and the like.

The operation of attaching the semiconductor wafer to the adhesive film 100 is sometimes performed by human hands, but it is usually performed by an apparatus called an automatic laminator in which a roll-shaped adhesive film is attached.

As the back grinding method, well-known grinding methods such as a throughfeed method and an infeed method can be used. While pouring water on the semiconductor wafer and the grinding stone and cooling them, each grinding is performed. After the back grinding is completed, chemical etching is performed as necessary. The chemical etching can be performed by the following method or the like: immersing the semiconductor wafer in a state where the adhesive film 100 is pasted in a material selected from the group consisting of hydrogen fluorine Acid, nitric acid, sulfuric acid, acetic acid, etc. alone or in a mixture of acidic aqueous solutions, potassium hydroxide aqueous solutions, sodium hydroxide aqueous solutions, and other alkaline aqueous solutions in the etching solution. This etching is performed for the purpose of removal of strain generated on the back surface of the semiconductor wafer, further thinning of the wafer, removal of oxide films, etc., and pre-processing when forming electrodes on the back surface.

After the back grinding and chemical etching are completed, the adhesive film 100 is peeled from the surface of the semiconductor wafer. This series of operations is sometimes performed manually, but 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 cleaned as necessary. Examples of the cleaning method include wet cleaning such as water cleaning and solvent cleaning, and dry cleaning such as plasma cleaning. In the case of wet cleaning, ultrasonic cleaning can also be used together. These cleaning methods are appropriately selected according to the contamination status of the surface of the semiconductor wafer.

The embodiments of the present invention have been described above, but these are examples of the present invention, and various configurations other than those described above may be adopted.

[Example]

Hereinafter, the present invention will be specifically described with examples and comparative examples, but the present invention is not limited to these.

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

<Substrate layer>

Polyethylene terephthalate film (thickness 50μm)

<Resin for forming concavo-convex absorbent resin layer>

Concave-convex absorbent resin 1: Ethylene. Vinyl acetate copolymer (density: 960kg/m ³ , manufactured by Du Pont-Mitsui Polychemicals "EVAFLEX EV150")

<Material for forming antistatic layer>

Antistatic layer forming material 1: Conductive material containing polyethylene dioxythiophene/polystyrene sulfonic acid (PEDOT/PSS) (manufactured by Nagase ChemteX, trade name: denatron) P-504CT)

<Ion conductivity additives>

Ion conductivity additive 1: Tetradecyl dimethyl benzyl ammonium chloride (manufactured by NOF Corporation, trade name: Nissan Cation (Nissan Cation) M ₂ -100)

<Photoinitiator>

Photoinitiator 1: Benzyl dimethyl ketal (manufactured by BASF, 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 0.5 parts by mass of benzoyl peroxide as a polymerization initiator were mixed. This was added dropwise at 85°C for 5 hours while stirring in a nitrogen-replaced flask containing 20 parts by mass of toluene and 80 parts by mass of ethyl acetate, and further stirred for 5 hours for reaction. After the reaction, the solution was cooled, and 10 parts by mass of toluene, 7 parts by mass of methacryloxyethyl isocyanate (manufactured by Showa Denko Co., Ltd., product name: Karenz MOI) were added thereto, and 0.02 parts by mass of dibutyltin dilaurate was reacted at 85°C for 12 hours while blowing air to obtain a solution of adhesive polymer 1 into which a polymerizable carbon-carbon double bond was introduced.

With respect to 100 parts by mass of the copolymer (solid content), benzyl dimethyl ketal (manufactured by BASF Co., Ltd., Irgacure 651) 7 mass as a photoinitiator is added to the solution Parts, isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals Co., Ltd., trade name: Olestar P49-75S) 2 parts by mass, as having two or more polymerizable carbon-carbon double bonds in one molecule Dipentaerythritol hexaacrylate of low molecular weight compound (manufactured by Toagosei Co., Ltd., trade name: Aronix M-400) 12 parts by mass, ion conductivity additive 1: tetradecyl dimethyl benzyl chloride 0.5 parts by mass of ammonium hydroxide (manufactured by NOF Corporation, Nissan Cation M ₂ -100) to obtain an adhesive resin layer coating liquid 1.

<Coating Liquid 2 for Adhesive Resin Layer>

Except that the ion conductive additive 1 was not added, the adhesive resin layer coating liquid 2 was obtained in the same manner as the adhesive resin layer coating liquid 1.

<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, 5 parts by mass of glycidyl methacrylate, and 0.5 parts by mass of benzoyl peroxide as a polymerization initiator Parts mix. This was added dropwise at 80°C for 5 hours while stirring in a nitrogen-replaced flask containing 65 parts by mass of toluene and 50 parts by mass of ethyl acetate, and further stirred for 5 hours for reaction. After the reaction, the solution was cooled, and 25 parts by mass of xylene, 2.5 parts by mass of acrylic acid, and ion conductivity additive 1: 0.5 parts by mass of tetradecyl dimethyl benzyl ammonium chloride were added to the solution while blowing in The air side was allowed to react at 85°C for 32 hours to obtain a solution of adhesive polymer 3 into which a polymerizable carbon-carbon double bond was introduced.

With respect to 100 parts by mass of the copolymer (solid content), benzyl dimethyl ketal (manufactured by BASF Co., Ltd., Irgacure 651) 7 mass as a photoinitiator is added to the solution Parts, isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals Co., Ltd., trade name: Olestar P49-75S) 2 parts by mass, as having two or more polymerizable carbon-carbon double bonds in one molecule 12 parts by mass of dipentaerythritol hexaacrylate (manufactured by Toagosei Co., Ltd., trade name: Aronix M-400) of a low-molecular-weight compound, to obtain a coating liquid 3 for an adhesive resin layer.

[Example 1]

On the polyethylene terephthalate film used as the base layer, the concave-convex absorbent resin 1 used as the concave-convex absorbent resin layer was extrusion-laminated with a thickness of 195 μm to obtain a two-layer laminated film.

Then, the antistatic layer forming material 1 is coated on a separately prepared release film and dried to form an antistatic film, and the antistatic film is laminated on the concavo-convex absorbent resin layer to form a thickness 0.1μm antistatic layer.

Then, the coating liquid 1 for an adhesive resin layer was apply|coated on the antistatic layer of the laminated film obtained, and it dried, and the adhesive resin layer of thickness 40 micrometers was formed, and the adhesive film was obtained.

The following evaluations were performed for the obtained adhesive film. The obtained results are shown in Table 1.

[Example 2 and Example 3, Comparative Example 1 to Comparative Example 4]

Except that the presence or absence of the formation of the antistatic layer, the thickness of the adhesive resin layer, the type of the adhesive resin layer coating liquid, etc. were changed to those shown in Table 1, the same as in Example 1. The adhesive films were made separately in the same way.

The following evaluations were performed for the obtained adhesive films, respectively. The obtained results are shown in Table 1, respectively.

<evaluation>

(1) Measurement of saturated electrostatic voltage

In an environment of 25°C, a high-pressure mercury lamp (UVX-02528S1AJA02 manufactured by USHIO Electric Co., Ltd.) was used to irradiate the adhesive resin layer in the adhesive film ^{with an irradiation intensity of 100mW/cm 2 with an ultraviolet amount of 1080mJ/cm 2 and} a dominant wavelength of 365nm. The ultraviolet rays light harden the adhesive resin layer. Then, the static honestmeter H-0110-S4 manufactured by SSD Electrostatic Company was used as the measuring device, and the applied voltage was 10kV, the distance between the sample and the electrode was 20mm, 25°C, and 50%RH. A voltage was applied to the surface of the adhesive resin layer for 30 seconds, and the saturated electrostatic voltage (V ₁ ) of the surface of the adhesive resin layer and the half-life of the saturated electrostatic voltage V _{1 were calculated in accordance with JIS L1094.}

In addition, except that the amount of ultraviolet light was changed ^{to 200mJ/cm 2} to 540mJ/cm ² , the saturation electrostatic voltage and saturation of the surface of the adhesive resin layer were measured in the same procedure as the measurement of the saturated electrostatic voltage (V _{1 ).} The half-life of electrostatic voltage.

(2) Determination of adhesion

The adhesive force of the surface of the adhesive resin layer was measured by the following method: the adhesive resin layer of the adhesive film was bonded to the polyimide film (product name: Kapton 200H, Toray Du Pont- Toray), in an environment of 25°C, a high-pressure mercury lamp is used from the base layer side of the adhesive film at an intensity of 100mW/cm ^{2 to} irradiate an ultraviolet amount of 1080mJ/cm ² with a dominant wavelength of 365nm to make the adhesive The resin layer is light-cured. Next, the polyimide film was peeled off from the adhesive film, and a probe tack tester ("Probe Tack Tester manufactured by TESTING MACHINES Inc.: Model 80-02-01") was used as In the measuring device, a probe with a diameter of 5 mm is in contact with the surface of the adhesive resin layer at a speed of 10 mm/sec. After contacting with ^{a contact load of 0.98 N/cm 2} for 10 seconds, the probe is self-adhesive at a speed of 10 mm/sec. The surface of the resin layer is peeled off in the vertical direction.

Further, except that the amount of ultraviolet others ^{200mJ / cm 2 ~ 540mJ / cm} 2, to the measurement of the adhesion forces of the same order, were measured adhesion surface of the adhesive resin layer.

(3) Evaluation of antistatic property

The antistatic property of the adhesive film was evaluated according to the following criteria.

◎: Saturated electrostatic voltage V ₁ is below 1.0kV

○: The saturated electrostatic voltage V ₁ exceeds 1.0kV and is 2.0kV or less

×: The saturated electrostatic voltage V ₁ exceeds 2.0kV

(4) Evaluation of adhesion on the surface of semiconductor wafers

The adhesiveness of the semiconductor wafer surface was evaluated according to the following criteria.

○: The adhesive force of the adhesive resin layer 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 not irradiated with ultraviolet rays is less than 10 N/cm ²

(5) Evaluation of contamination resistance on the surface of semiconductor wafers

The contamination resistance of the surface of the semiconductor wafer was evaluated according to the following criteria.

○: The adhesive force of the adhesive resin layer photocured by ultraviolet rays of 1080mJ/cm ^{2 is 0.1 N/cm 2} or less

×: The adhesive force of the adhesive resin layer photocured by ultraviolet rays of 1080mJ/cm ^{2 exceeds 0.1 N/cm 2}

(6) Evaluation of uneven absorbency

○: When attached to the bump electrode forming surface of a semiconductor wafer with bump electrodes, the bump electrode is not cracked, and the adhesion to the semiconductor wafer is good

×: When attached to the bump electrode forming surface of a semiconductor wafer with bump electrodes, the bump electrode is broken, or the adhesion to the semiconductor wafer is poor

A bumped semiconductor wafer equipped with bumps with a bump height of 80 μm, a bump pitch of 300 μm, and a bump diameter of 150 μm was used for the evaluation of uneven absorbency. For the adhesive film application, a roll laminator (product name : DR3000II manufactured by Nitto Seiki Co., Ltd.) was carried out under the conditions of a roll speed of 2 mm/sec, a roll pressure of 0.4 MPa, and a stage temperature of 80° C., and an optical microscope was used to evaluate the unevenness absorbency after attachment.

[Table 1]

The adhesive films of Examples 1 to 3 have an excellent balance of adhesion to the surface of semiconductor wafers and contamination resistance, and excellent antistatic properties. The adhesive films of Examples 1 to 3 include substrates in turn. The material layer, the antistatic layer and the adhesive resin layer, and the adhesive resin layer contains ion conductive additives. That is, according to the adhesive film 100 for semiconductor wafer processing of this embodiment, it can be understood that the antistatic property after ultraviolet curing is excellent, the amount of static electricity generated when peeling from the semiconductor wafer can be suppressed, and the quality can be stably obtained. Excellent semiconductor parts.

In contrast, the adhesive films of Comparative Examples 1 to 3 in which the adhesive resin layer does not contain an ion conductive additive, and the adhesive films of Comparative Examples 3 and 4 that do not include an antistatic layer have poor antistatic properties.

This application claims priority based on Japanese application Japanese Patent Application No. 2016-130822 for which an application was filed on June 30, 2016, and all the disclosures thereof are incorporated into this application.

10‧‧‧Substrate layer

30‧‧‧Antistatic layer

40‧‧‧Adhesive resin layer

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

Claims (16)

An adhesive film for semiconductor wafer processing, which is an adhesive film used to protect the surface of a semiconductor wafer or fix the semiconductor wafer, and sequentially includes a substrate layer, an antistatic layer, and an adhesive resin layer. The resin layer contains an ion-conducting additive, and the saturated electrostatic voltage V ₁ of the adhesive resin layer surface after ultraviolet curing measured by the following method is 1.0kV or less; (Method) In an environment of 25°C, use a high-pressure mercury lamp to Irradiation intensity of 100mW/cm ² irradiates the adhesive resin layer with an ultraviolet amount of 1080mJ/cm ^{2 and} a dominant wavelength of 365nm ultraviolet rays, so that the adhesive resin layer is light-cured; A voltage was applied to the surface of the adhesive resin layer at a distance of 20 mm, 25° C., and 50% RH for 30 seconds, and the saturated electrostatic voltage (V ₁ ) of the surface of the adhesive resin layer was calculated according to Japanese Industrial Standard L1094. The adhesive film for processing semiconductor wafers as described in claim 1, wherein the adhesive resin layer includes an ultraviolet-curable adhesive resin. The adhesive film for semiconductor wafer processing as described in the scope of patent application 2, wherein the content of the ion conductive additive in the adhesive resin layer is relative to 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 item 1 or item 2 of the scope of the patent application, wherein the ion conductive additive comprises a cationic surfactant, an anionic surfactant, and a nonionic surfactant One or more of two kinds of agents, amphoteric surfactants and ionic liquids. The adhesive film for semiconductor wafer processing according to the first or second patent application, wherein the thickness of the adhesive resin layer is 5 μm or more and 550 μm or less. The adhesive film for semiconductor wafer processing as described in item 1 or item 2 of the scope of patent application is a back grinding tape. The adhesive film for semiconductor wafer processing according to item 1 or item 2 of the scope of patent application, wherein the antistatic layer includes a conductive polymer. The adhesive film for semiconductor wafer processing as described in claim 1 or 2, further comprising a concavo-convex absorptive resin layer between the base layer and the antistatic layer. An adhesive film for semiconductor wafer processing, which is an adhesive film used to protect the surface of a semiconductor wafer or fix the 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, and the adhesive force of the surface of the adhesive resin layer after ultraviolet curing measured by the following method is 0.1 N/cm ² or less; (Method) The adhesive resin layer is measured by the following method Adhesion of the surface of the adhesive: the adhesive resin layer of the adhesive film is attached to the polyimide film, and a high pressure is applied from the substrate layer side of the adhesive film under an environment of 25°C The mercury lamp irradiates ultraviolet rays with a dominant wavelength of 365 nm with an ultraviolet amount of 1080 mJ/cm ² at an irradiation intensity of 100 mW/cm ^{2 to} light-harden the adhesive resin layer; then, the polyimide film is peeled from the adhesive film , Using a probe tack tester as a measuring device, contact a probe with a diameter of 5 mm with the surface of the adhesive resin layer at a speed of 10 mm/sec, and contact with a contact load of ^{0.98 N/cm 2 for 10 seconds.} The probe was peeled from the surface of the adhesive resin layer in a vertical direction at a speed of 10 mm/sec. The adhesive film for semiconductor wafer processing according to the ninth patent application, wherein the adhesive resin layer contains an ultraviolet curable adhesive resin. The adhesive film for semiconductor wafer processing according to claim 10, wherein the content of the ion conductive additive in the adhesive resin layer is relative to 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 as described in item 9 or item 10 of the scope of patent application, wherein The ion conductive additive includes one or two or more selected from cationic surfactants, anionic surfactants, nonionic surfactants, amphoteric surfactants, and ionic liquids. The adhesive film for semiconductor wafer processing according to claim 9 or 10, wherein the thickness of the adhesive resin layer is 5 μm or more and 550 μm or less. The adhesive film for semiconductor wafer processing as described in item 9 or item 10 of the scope of patent application is a back grinding tape. The adhesive film for semiconductor wafer processing according to item 9 or item 10 of the scope of patent application, wherein the antistatic layer includes a conductive polymer. The adhesive film for semiconductor wafer processing according to claim 9 or 10, further comprising a concave-convex absorptive resin layer between the base layer and the antistatic layer.

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