JP2018006541A - Method for manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of stably grinding a semiconductor wafer without damaging a bump electrode and the semiconductor wafer and peeling the semiconductor wafer and an adhesive film, suppressing breakdown of a circuit, and stably obtaining a semiconductor device with excellent quality.SOLUTION: A method for manufacturing a semiconductor device comprises at least three steps of: preparing a structure including a semiconductor wafer having a circuit formation surface and an adhesive film 100 stuck to the circuit formation surface side of the semiconductor wafer; back-grinding a surface on the side opposite to the circuit formation surface side of the semiconductor wafer; and removing the adhesive film from the semiconductor wafer after irradiating the adhesive film with ultraviolet light. The adhesive film comprises a base material layer 10, an unevenness absorptivity resin layer 20, an antistatic layer 30, and an adhesive resin layer 40 in this order, and is used so that the adhesive resin layer becomes the circuit formation surface side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a semiconductor device.

In the semiconductor device manufacturing process, in the process of grinding the semiconductor wafer, an adhesive film is attached to the semiconductor wafer in order to prevent damage to the semiconductor wafer.
As such an adhesive film, a film in which an ultraviolet curable adhesive resin layer is laminated on a base film is generally used. When this 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 that 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, static electricity called peeling charging may occur when the adhesive film is peeled from the semiconductor wafer. In some cases, the static electricity generated in this way destroys the circuit formed on the semiconductor wafer (electrostatic breakdown), and foreign matters such as dust adhere to the circuit formed on the semiconductor wafer.
In particular, with the recent increase in the density of semiconductor wafers and the reduction in wiring pitch, semiconductor wafers tend to be more susceptible to static electricity than ever.
In view of such circumstances, in recent years, it is required to further improve the antistatic performance of the adhesive film used for preventing damage to the semiconductor wafer in the manufacturing process of the semiconductor device.

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

Patent Document 1 discloses a pressure-sensitive adhesive tape composed of a base film and a photocurable pressure-sensitive adhesive layer, the antistatic layer containing a conductive polymer on at least one side of the base film, and the antistatic layer. It has a pressure-sensitive adhesive layer containing a photocurable unsaturated carbon bond in the base polymer molecule, and the surface resistivity on the pressure-sensitive adhesive layer side before and after UV curing is 1 × 10 ^{6 to} 5 × 10 ¹² Ω / □, the thickness of the pressure-sensitive adhesive layer is 20 to 250 μm, and the pressure-sensitive adhesive layer is peeled off by 90 ° after UV curing when the pressure-sensitive adhesive tape is bonded to a silicon mirror wafer (according to JIS Z 0237; peeling) An antistatic semiconductor processing pressure-sensitive adhesive tape characterized in that the speed is 50 mm / min) is 0.15 to 0.25 N / 25 mm is described.

JP 2011-210944 A

As described above in the background art section above, in recent years, the technical level required for the viewpoint of countermeasures against static electricity of an adhesive film for processing semiconductor wafers is increasing.
The present inventors have found the following problems with respect to a conventional adhesive film for processing a semiconductor wafer as described in Patent Document 1.
First, according to the study by the present inventors, a pressure-sensitive adhesive film in which a base film, an antistatic layer, and a pressure-sensitive adhesive layer are laminated in this order as described in Patent Document 1 is bumped on the surface. When used for semiconductor wafers with electrodes formed, the bumps and semiconductors are not suitable for bonding or grinding the semiconductor wafer because of the insufficient absorbability of the semiconductor wafer surface irregularities caused by the bump electrodes. It has been found that the wafer is damaged, the adhesion between the semiconductor wafer and the adhesive film becomes insufficient, and the grinding water enters and causes contamination of the semiconductor wafer.
Further, according to the study by the present inventors, in the adhesive film as described in Patent Document 1, the thickness of the adhesive layer is improved in order to improve the absorbability with respect to the unevenness of the semiconductor wafer surface caused by the bump electrode. When the thickness of the adhesive film is increased, the distance between the surface of the pressure-sensitive adhesive layer and the antistatic layer becomes longer, and it has become clear that the antistatic property of the adhesive film may be deteriorated.
That is, according to the study by the present inventors, in the conventional adhesive film for processing semiconductor wafers, there may be a trade-off relationship between the absorbability to the irregularities on the semiconductor wafer surface and the antistatic property. It was revealed. That is, the present inventors have found that there is room for improvement in the conventional adhesive film for processing a semiconductor wafer in terms of improving the absorbability and antistatic property against unevenness on the surface of the semiconductor wafer in a balanced manner. .

  The present invention has been made in view of the above circumstances, and it is possible to stably grind a semiconductor wafer without damaging the bump electrode or the semiconductor wafer or peeling off the semiconductor wafer and the adhesive film. The present invention also provides a method of manufacturing a semiconductor device that can suppress the dielectric breakdown of the circuit and can stably obtain a semiconductor device having excellent quality.

  The inventors of the present invention have made extensive studies in order to achieve the above problems. As a result, by making the layer structure of the adhesive film a base material layer, a concavo-convex absorbent resin layer, an antistatic layer, and an adhesive resin layer in this order, the above trade-off is achieved. The present invention has been completed by finding that the relationship can be improved and that both the absorbability and the antistatic property against the irregularities on the surface of the semiconductor wafer can be achieved.

  According to the present invention, the following method for manufacturing a semiconductor device is provided.

[1]
Preparing a structure comprising a semiconductor wafer having a circuit forming surface and an adhesive film bonded to the circuit forming surface side of the semiconductor wafer (A);
Back grinding the surface of the semiconductor wafer opposite to the circuit forming surface side (B),
Removing the adhesive film from the semiconductor wafer after irradiating the adhesive film with ultraviolet rays (C);
A method for manufacturing a semiconductor device comprising at least
As the above adhesive film,
A base material layer, a ruggedness absorbing resin layer, an antistatic layer, and an adhesive resin layer are provided in this order, and an adhesive used so that the adhesive resin layer is on the circuit forming surface side of the semiconductor wafer. For manufacturing a semiconductor device using a conductive film.
[2]
In the method for manufacturing a semiconductor device according to the above [1],
A method of manufacturing a semiconductor device, wherein a bump electrode is formed on the circuit forming surface of the semiconductor wafer.
[3]
In the method for manufacturing a semiconductor device according to the above [2],
In the step (A), the semiconductor device manufacturing method further includes a step (A2) of manufacturing the structure by heating and sticking the adhesive film to the circuit forming surface of the semiconductor wafer.
[4]
In the method for manufacturing a semiconductor device according to the above [2] or [3],
A method of manufacturing a semiconductor device, wherein H / d is 0.01 or more and 1 or less, where the height of the bump electrode is H [μm] and the thickness of the uneven absorbent resin layer is d [μm].
[5]
In the method for manufacturing a semiconductor device according to any one of [1] to [4],
The manufacturing method of the semiconductor device whose thickness of the said adhesive resin layer is less than 30 micrometers.
[6]
In the method for manufacturing a semiconductor device according to any one of [1] to [5],
The manufacturing method of the semiconductor device whose thickness of the said uneven | corrugated absorbent resin layer is 10 micrometers or more and 500 micrometers or less.
[7]
In the method for manufacturing a semiconductor device according to any one of [1] to [6],
The manufacturing method of the semiconductor device in which the said adhesive resin layer contains an ion conductive additive.
[8]
In the method for manufacturing a semiconductor device according to the above [7],
The said ion conductive additive is a manufacturing method of the semiconductor device containing 1 type, or 2 or more types selected from a cationic surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant, and an ionic liquid.
[9]
In the method for manufacturing a semiconductor device according to any one of [1] to [8],
The method for manufacturing a semiconductor device, wherein the adhesive resin layer includes an ultraviolet curable adhesive resin.
[10]
In the method for manufacturing a semiconductor device according to any one of [1] to [9],
In the step (C), the adhesive film is photocured by irradiating the adhesive film with ultraviolet rays having a dose of 300 mJ / cm ² or more, thereby reducing the adhesive strength of the adhesive resin layer. And then, removing the adhesive film from the semiconductor wafer.
[11]
In the method for manufacturing a semiconductor device according to any one of [1] to [10],
Is measured by the following methods, the production method of the saturated charging voltage V ₁ of the said adhesive resin layer surface after UV curing semiconductor device is less than 2.5 kV.
(Method)
The adhesive resin layer is photocured by irradiating ultraviolet light having a dominant wavelength of 365 nm with an irradiation intensity of 100 mW / cm ² and an ultraviolet light amount of 1080 mJ / cm ² using a high-pressure mercury lamp in an environment of 25 ° C. Let Next, 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 adhesive resin layer according to JIS L1094. The saturation voltage (V ₁ ) of the surface of is calculated.
[12]
In the method for manufacturing a semiconductor device according to any one of [1] to [11],
The manufacturing method of the semiconductor device whose tack force of the surface of the said adhesive resin layer after the ultraviolet curing measured by the following method is 0.1 N / cm < ² > or less.
(Method)
The adhesive resin layer of the adhesive film is bonded to a polyimide film, and an ultraviolet ray having a main wavelength of 365 nm is irradiated from a substrate layer side of the adhesive film under an environment of 25 ° C. with an irradiation intensity of 100 mW. / cm ² UV dose 1080MJ / cm ² irradiated to photocuring the adhesive resin layer. Next, the polyimide film is peeled off from the adhesive film, and a probe tack tester is used as a measuring device to bring the probe having a diameter of 5 mm into contact with the surface of the adhesive resin layer at a rate of 10 mm / sec. Measure the tack force on the surface of the adhesive resin layer by peeling the probe from the surface of the adhesive resin layer in the vertical direction at a speed of 10 mm / second after contacting with a contact load of 10 cm / cm ² for 10 seconds. To do.

  According to the present invention, it is possible to stably grind a semiconductor wafer without damaging the bump electrode or the semiconductor wafer, or causing the semiconductor wafer and the adhesive film to peel off and cause contamination of the semiconductor wafer due to intrusion of grinding water. In addition, it is possible to provide a method of manufacturing a semiconductor device that can suppress the dielectric breakdown of the circuit and can stably obtain a semiconductor device with excellent quality.

It is sectional drawing which showed typically an example of the structure of the adhesive film of embodiment which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, similar constituent elements are denoted by common reference numerals, and description thereof is omitted as appropriate. Moreover, the figure is a schematic diagram and does not match the actual dimensional ratio. In addition, “A to B” in the numerical range represents A or more and B or less unless otherwise specified. In the present embodiment, “(meth) acryl” means acrylic, methacrylic, or both acrylic and methacrylic.

FIG. 1 is a cross-sectional view schematically showing an example of the structure of an adhesive film 100 according to an embodiment of the present invention.
The semiconductor device manufacturing method according to the present embodiment includes at least the following three steps.
(A) The process of preparing the structure provided with the semiconductor wafer which has a circuit formation surface, and the adhesive film 100 bonded together by the said circuit formation surface side of the said semiconductor wafer (B) The said circuit formation surface of the said semiconductor wafer (C) The step of removing the adhesive film 100 from the semiconductor wafer after irradiating the adhesive film 100 with ultraviolet rays. In the method of manufacturing a semiconductor device according to the present embodiment, As the adhesive film 100, the base material layer 10, the concavo-convex absorbent resin layer 20, the antistatic layer 30, and the adhesive resin layer 40 are provided in this order, and the adhesive resin layer 40 is formed on the semiconductor wafer. The adhesive film used so that it may become the said circuit formation surface side is used.

1. Adhesive film First, the adhesive film 100 used with the manufacturing method of the semiconductor device which concerns on this embodiment is demonstrated.
As described above, in recent years, the technical level required for the viewpoint of static electricity countermeasures for adhesive films for processing semiconductor wafers has been increasing. In particular, when using a semiconductor wafer in which bump electrodes such as solder bumps and copper pillar bumps are formed on a high-density circuit of a semiconductor wafer on which high-density circuits are arranged, bump electrodes formed on the semiconductor wafer due to static electricity are used. Such demands are becoming more prominent because the destruction (short-circuiting) of the included circuit tends to occur.
For this reason, it has been required to realize an adhesive film for processing semiconductor wafers that is superior in antistatic properties.

Here, the present inventors relate to a pressure-sensitive adhesive film in which a base film, an antistatic layer, and a pressure-sensitive adhesive layer are laminated in this order as described in Patent Document 1, and have the following problems. I found it.
First, according to the study by the present inventors, when an adhesive film as described in Patent Document 1 is used for a semiconductor wafer having a bump electrode formed on the surface, a semiconductor caused by the bump electrode is used. Absorption on the surface of the wafer surface is insufficient, so when bonding or grinding the semiconductor wafer, the bump electrodes may be damaged, the semiconductor wafer may be damaged, the semiconductor wafer and the adhesive film It has been found that the adhesion between the two becomes insufficient, and the grinding water enters and causes contamination of the semiconductor wafer.
Furthermore, according to the study by the present inventors, in the adhesive film as described in Patent Document 1, in order to improve the absorbability with respect to the unevenness of the semiconductor wafer surface caused by the bump electrode, It has been clarified that when the thickness is increased, the distance between the surface of the pressure-sensitive adhesive layer and the antistatic layer becomes longer, and the antistatic property of the pressure-sensitive adhesive film may be deteriorated.
That is, according to the study by the present inventors, in the conventional adhesive film for processing semiconductor wafers, there may be a trade-off relationship between the absorbability to the irregularities on the semiconductor wafer surface and the antistatic property. It was revealed. That is, the present inventors have found that there is room for improvement in the conventional adhesive film for processing a semiconductor wafer in terms of improving the absorbability and antistatic property against unevenness on the surface of the semiconductor wafer in a balanced manner. .

In order to realize a pressure-sensitive adhesive film for processing semiconductor wafers that can improve the absorption and antistatic properties with respect to the irregularities on the surface of the semiconductor wafer in a well-balanced manner based on the above-described knowledge about the pressure-sensitive adhesive film for processing semiconductor wafers. In addition, earnest examination was repeated. As a result, the above-mentioned trade-off relationship can be improved by adopting a layer configuration comprising a base material layer, a concavo-convex absorbent resin layer, an antistatic layer, and an adhesive resin layer in this order, and the semiconductor wafer surface It has been found for the first time that it is possible to achieve both absorptivity to unevenness and antistatic property.
That is, the adhesive film 100 according to the present embodiment has the above layer structure, so that it has excellent absorbability with respect to the irregularities on the surface of the semiconductor wafer and can suppress the amount of static electricity generated when peeling from the semiconductor wafer. It is possible to stably obtain an excellent semiconductor device.

In the adhesive film 100 according to the present embodiment, the saturation voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing, which is measured by the following method, is preferably 3.0 kV or less, more preferably 2.5 kV. Or less, more preferably 2.0 kV or less, even more preferably 1.5 kV or less, even more preferably 1.0 kV or less, and particularly preferably 0.5 kV or less.
(Method)
The adhesive resin layer 40 is photocured by irradiating ultraviolet light having a main wavelength of 365 nm with an irradiation intensity of 100 mW / cm ² and an ultraviolet light amount of 1080 mJ / cm ^{2 in} an environment of 25 ° C. in an environment of 25 ° C. Let Next, 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 of 20 mm, 25 ° C., and 50% RH, and the adhesive resin layer 40 was applied according to JIS L1094. The saturation voltage (V ₁ ) of the surface of is calculated.

Saturated electrification voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing by the above-described upper limit or less, it is possible to antistatic properties of the semiconductor wafer surface more even more favorable.
The lower limit value of the saturation voltage V ₁ of the adhesive resin layer 40 after UV curing is, for example, 0.01 kV or more, and preferably 0 kV.

In the present embodiment, for example, the saturation of the adhesive resin layer 40 after UV curing is performed by appropriately adjusting the type and blending ratio of each component constituting the adhesive resin layer 40, the thickness of the adhesive resin layer 40, and the like. a band voltages V ₁ can be controlled to below the upper limit.
Among them, for example, whether the ion conductive additive in the adhesive resin layer 40, the thickness or the like of the adhesive resin layer 40 is desired numerical saturated electrification voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing It is mentioned as an element to make a range.
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 reduced, the saturation voltage V ₁ can be reduced.
Since the adhesive film 100 according to the present embodiment includes the uneven absorbent resin layer 20, the thickness of the adhesive resin layer 40 can be reduced while maintaining the absorbability with respect to the unevenness on the surface of the semiconductor wafer. By reducing the thickness of the adhesive resin layer 40, the distance between the adhesive surface with the semiconductor wafer (that is, the surface of the adhesive resin layer 40) and the antistatic layer 30 can be reduced. V ₁ can be effectively reduced.

In the pressure-sensitive adhesive film 100 according to the present embodiment, V ₁ / V ₂ is preferably 5 when the saturation voltage on the surface of the pressure-sensitive adhesive resin layer 40 after ultraviolet curing, measured by the following method, is V _2. 0.0 or less, more preferably 3.0 or less, and even more preferably 2.5 or less. When V ₁ / V ₂ is equal to or lower than the above upper limit value, the amount of static electricity generated when peeling from the semiconductor wafer can be more stably suppressed, and a semiconductor device having excellent quality can be obtained more stably.
(Method)
The adhesive resin layer 40 is photocured by irradiating ultraviolet light having a main wavelength of 365 nm with an irradiation intensity of 100 mW / cm ² and an ultraviolet ray amount of 200 mJ / cm ^{2 in} an environment of 25 ° C. in an environment of 25 ° C. Let Next, 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 of 20 mm, 25 ° C., and 50% RH, and the adhesive resin layer 40 was applied according to JIS L1094. The saturation voltage (V ₂ ) of the surface of is calculated.

In the adhesive film 100 according to this embodiment, the half-life of the saturation voltage V ₁ of the adhesive resin layer 40 after UV curing is preferably 100 seconds or less, more preferably 50 seconds or less, and even more preferably. Is 30 seconds or less, more preferably 10 seconds or less, and particularly preferably 1 second or less.
Here, the half-life is saturated charging voltage V _1, in the measurement of the saturated charging voltage V _1, until the value of the exit and charged voltage from the voltage application to the surface of the adhesive resin layer 40 is reduced by half Of time.
Adhesive film 100 according to this embodiment, since the saturation zone voltage V ₁ of the adhesive resin layer 40 after ultraviolet curing is not more than the above upper limit, it is possible to realize such a short half-life, excellent antistatic properties The adhesive film 100 can be obtained.

In the adhesive film 100 according to this embodiment, the tack force of 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, and 0.05 N / Cm ² or less is more preferable, and 0.01 N / cm ² or less is more preferable.
When the tack force on the surface of the adhesive resin layer 40 after UV curing is not more than the above upper limit value, it becomes easier to peel the adhesive film 100 from the semiconductor wafer surface, and the adhesive resin layer is applied to the semiconductor wafer surface. It can be further suppressed that a part of 40 remains, or that the semiconductor wafer has a problem due to peeling of the adhesive film 100.
(Method)
The adhesive resin layer 40 of the adhesive film 100 is bonded to a polyimide film (product name: Kapton 200H, manufactured by Toray DuPont), and high pressure mercury is applied from the substrate layer 10 side of the adhesive film 100 in an environment of 25 ° C. The adhesive resin layer 40 is photocured by irradiating ultraviolet rays having a dominant wavelength of 365 nm with an irradiation intensity of 100 mW / cm ² and an ultraviolet ray amount of 1080 mJ / cm ² using a lamp. Next, the polyimide film is peeled off from the adhesive film 100, and a probe tack tester (for example, “TESTING MACHINES Inc. probe tack tester: Model 80-02-01”) is used as a measuring device. The surface of the adhesive resin layer 40 is brought into contact with the surface of the adhesive resin layer 40 at a speed of 10 mm / second, and contacted with a contact load of 0.98 N / cm ² for 10 seconds, and then the probe is attached to the adhesive resin layer 40 at a speed of 10 mm / second. The tack force of the surface of the adhesive resin layer 40 is measured by a method of peeling from the surface in the vertical direction.

  The total thickness of the adhesive film 100 according to this embodiment is preferably 25 μm or more and 1000 μm or less, more preferably 50 μm or more and 600 μm or less, from the balance of mechanical properties and handleability.

The adhesive film 100 according to the present embodiment is used for protecting a circuit forming surface of a semiconductor wafer in a manufacturing process of a semiconductor device, and more specifically, a back grinding process that is one of the manufacturing processes of a semiconductor device. 1 is used as a back grind tape used for protecting a circuit forming surface (that is, a circuit surface including a circuit pattern) of a semiconductor wafer.
Here, when the semiconductor wafer to be attached is a semiconductor wafer having a bump electrode such as a solder bump or a copper pillar bump formed on the circuit forming surface, the semiconductor is caused by static electricity generated when the adhesive film is peeled from the semiconductor wafer. Although electrostatic breakdown or the like in which the circuit formed on the wafer is destroyed is likely to occur, by using the adhesive film 100 according to the present embodiment, the semiconductor wafer having the bump electrode formed on such a surface is also used. It is possible to more reliably suppress electrostatic breakdown and the like.
Moreover, since the adhesive film 100 which concerns on this embodiment has the favorable absorbability with respect to the unevenness | corrugation of the semiconductor wafer surface resulting from a bump electrode, by using the adhesive film 100 which concerns on this embodiment, adhesive film sticking When the back surface of the semiconductor wafer is ground, excessive pressure is applied to the bump electrode part, and the semiconductor wafer can be prevented from being damaged, or the adhesion between the semiconductor wafer and the adhesive film is improved. The contamination of the semiconductor wafer due to the intrusion of the grinding water can be suppressed.

  It does not specifically limit as a semiconductor wafer which can apply the adhesive film 100 which concerns on this embodiment, A silicon wafer etc. are mentioned.

  Next, each layer which comprises the adhesive film 100 which concerns on this embodiment is demonstrated.

(Base material layer)
The base material layer 10 is a layer provided for the purpose of improving the handling properties, mechanical properties, heat resistance, and other properties of the adhesive film 100.
The base material layer 10 is not particularly limited as long as it has a mechanical strength capable of withstanding an external force applied when processing a semiconductor wafer, and examples thereof include a resin film.
A known thermoplastic resin can be used as the resin constituting the resin film. For example, polyolefins such as polyethylene, polypropylene, poly (4-methyl-1-pentene), poly (1-butene); polyesters such as polyethylene terephthalate and polybutylene terephthalate; nylon-6, nylon-66, polymetaxylene adipa Polyamide; Polyacrylate; Polymethacrylate; Polyvinyl Chloride; Polyetherimide; Ethylene / vinyl acetate copolymer; Polyacrylonitrile; Polycarbonate; Polystyrene; Ionomer; Polysulfone; Polyethersulfone; Polyphenylene ether, etc. One type or two or more types can be mentioned.
Among these, from the viewpoint of semiconductor wafer protection, one or more selected from polypropylene, polyethylene terephthalate, polyamide, and ethylene / vinyl acetate copolymer are preferable, and selected from polyethylene terephthalate and ethylene / vinyl acetate copolymer. One type or two or more types are more preferable.

The base material layer 10 may be a single layer or two or more layers.
The form of the resin film used to form the base material layer 10 may be a stretched film or a film stretched in a uniaxial direction or a biaxial direction. From the viewpoint of improving the mechanical strength of the film, a film stretched in a uniaxial direction or a biaxial direction is preferable.

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 a surface treatment in order to improve adhesion with other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coat treatment, or the like may be performed.

(Adhesive resin layer)
The adhesive film 100 according to 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 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 pressure sensitive adhesive include (meth) acrylic pressure sensitive adhesive, silicone pressure sensitive adhesive, urethane pressure sensitive adhesive, and the like.
The (meth) acrylic pressure-sensitive adhesive contains a (meth) acrylic pressure-sensitive adhesive resin as an essential component as an ultraviolet curable pressure-sensitive adhesive resin. The silicone-based adhesive contains a silicone-based adhesive resin as an essential component as an ultraviolet curable adhesive resin. The urethane-based adhesive contains a urethane-based adhesive resin as an essential component as an ultraviolet curable adhesive resin.
Among these, a (meth) acrylic pressure-sensitive adhesive is preferable from the viewpoint of facilitating adjustment of the adhesive strength.

  As a (meth) acrylic adhesive, a (meth) acrylic adhesive resin having a polymerizable carbon-carbon double bond in the molecule, and a low having two or more polymerizable carbon-carbon double bonds in the molecule. Examples of the pressure-sensitive adhesive include a molecular weight compound and a photoinitiator, and the pressure-sensitive adhesive obtained by crosslinking the (meth) acrylic pressure-sensitive adhesive resin with a crosslinking agent as necessary.

  The (meth) acrylic adhesive resin having a polymerizable carbon-carbon double bond in the molecule is specifically obtained as follows. First, a monomer having an ethylenic double bond and a copolymerizable monomer having a functional group (P) are copolymerized. Next, a functional group (P) contained in the copolymer and a monomer having a functional group (Q) capable of causing an addition reaction, a condensation reaction or the like with the functional group (P) are combined into a double bond in the monomer. Is allowed to react, leaving a polymerizable carbon-carbon double bond introduced into the copolymer molecule.

  Examples of the monomer having an ethylenic double bond include acrylic acid alkyl esters such as methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, butyl (meth) acrylate, and ethyl (meth) acrylate. Among them, one or two or more of monomers having an ethylenic double bond such as methacrylic acid alkyl ester monomers, vinyl esters such as vinyl acetate, (meth) acrylonitrile, (meth) acrylamide and styrene are used.

Examples of the copolymerizable monomer having the functional group (P) include (meth) acrylic acid, maleic acid, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, N-methylol (meth) acrylamide, (meth And acryloyloxyethyl isocyanate. These may be used alone or in combination of two or more. As for the ratio of the monomer which has the said ethylenic double bond, and the copolymerizable monomer which has a functional group (P), the latter 30-1 mass% is preferable with respect to the former 70-99 mass%. More preferably, it is 20-5 mass% of the latter with respect to the former 80-95 mass%.
As a monomer which has the said functional group (Q), the monomer similar to the copolymerizable monomer which has the said functional group (P) can be mentioned, for example.

  Functional group (P) and functional group 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) As the combination of (Q), a combination that easily undergoes an addition reaction, such as a carboxyl group and an epoxy group, a carboxyl group and an aziridyl group, and a hydroxyl group and an isocyanate group, is desirable. In addition, 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 between a carboxylic acid group and a hydroxyl group.

  Low molecular weight compounds having two or more polymerizable carbon-carbon double bonds in the molecule include tripropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetraacrylate, pentaerythritol tetra ( And (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. These may use 1 type (s) or 2 or more types. 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 to 20 parts by mass with respect to 100 parts by mass of the (meth) acrylic adhesive resin. Yes, more preferably 5 to 18 parts by mass.

  Photoinitiators include benzoin, isopropyl benzoin ether, isobutyl benzoin ether, benzophenone, Michler ketone, chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, acetophenone diethyl ketal, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy -2-methyl-1-phenylpropan-1-one and the like. These may be used alone or in combination of two or more. The addition amount of the photoinitiator is preferably 0.1 to 15 parts by mass, more preferably 5 to 10 parts by mass with respect to 100 parts by mass of the (meth) acrylic adhesive resin.

  You may add a crosslinking agent to the said ultraviolet curing adhesive. As a crosslinking agent, epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane -Tri-β-aziridinylpropionate, N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), N, N′-hexamethylene-1,6-bis (1-aziridine) Aziridine compounds such as carboxamide), and isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate and polyisocyanate. The ultraviolet curable pressure-sensitive adhesive may be any of a solvent type, an emulsion type, a hot melt type, and the like.

In general, the content of the crosslinking agent is preferably in a range in which the number of functional groups in the crosslinking agent does not exceed the number of functional groups in the (meth) acrylic adhesive resin. However, when a functional group is newly generated by the crosslinking reaction, or when the crosslinking reaction is slow, it may be contained excessively as necessary.
The content of the crosslinking agent in the (meth) acrylic pressure-sensitive adhesive is based on 100 parts by weight of the (meth) acrylic pressure-sensitive adhesive resin from the viewpoint of improving the balance between the heat resistance and adhesion of the pressure-sensitive resin layer 40. It is preferable that they are 0.1 mass part or more and 15 mass parts or less.

The adhesive resin layer 40 according to this embodiment preferably contains an ion conductive additive. Thereby, the antistatic property of the adhesive resin layer 40 can be improved.
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 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, tetradecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, didodecyldimethylammonium chloride, ditetradecyldimethylammonium. Chloride, dihexadecyldimethylammonium chloride, dioctadecyldimethylammonium chloride, dodecylbenzyldimethylammonium chloride, hexadecylbenzyldimethylammonium chloride, octadecylbenzyldimethylammonium chloride, palmityltrimethylammonium chloride, oleyltrimethyla Mo chloride, di Val Michiru benzyl ammonium chloride, dioleyl benzyl ammonium chloride, and the like.

  Examples of the anionic surfactant include alkyl diphenyl ether disulfonates such as diammonium dodecyl diphenyl ether disulfonate, sodium dodecyl diphenyl ether disulfonate, calcium dodecyl diphenyl ether disulfonate, sodium alkyl diphenyl ether disulfonate; sodium dodecylbenzene sulfonate, dodecylbenzene Alkyl benzene sulfonates such as ammonium sulfonate; alkyl sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate; aliphatic carboxylates such as fatty acid sodium and potassium oleate; sulfate salts containing polyoxyalkylene units (eg, polyoxy Sodium ethylene alkyl ether sulfate, polyoxyethylene alkyl ether Polyoxyethylene alkyl ether sulfate such as ammonium sulfate; polyoxyethylene alkyl phenyl ether sulfate sodium, polyoxyethylene alkyl phenyl ether sulfate such as ammonium polyoxyethylene alkyl phenyl ether sulfate; polyoxyethylene polycyclic sodium phenyl ether sulfate; Polyoxyethylene polycyclic phenyl ether ammonium sulfate such as polyoxyethylene polycyclic phenyl ether sulfate); naphthalene sulfonic acid formalin condensate such as sodium naphthalene sulfonic acid formalin condensate salt; sodium dialkyl sulfosuccinate, dialkyl sulfosuccinic acid di Alkylsulfosuccinates such as sodium; polyoxyethylene-polyoxypropylene glycol ester Ether sulfates; sulfonates or sulfate group and a polymerizable carbon - carbon (unsaturated) double bonds and a surfactant or the like having in the molecule thereof.

  Examples of the nonionic surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene tridecyl ether, polyoxyalkylene alkyl ether compounds such as polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, A polyoxyalkylene unit-containing ether compound such as a polyoxyalkylene alkyl phenyl ether compound such as polyoxyethylene nonylphenyl ether, a polyoxyalkylene polycyclic phenyl ether compound such as polyoxyethylene polycyclic phenyl ether; a polyoxyethylene monolaurate; Polyoxyalkylene alkyl ester compounds such as polyoxyethylene monostearate and polyoxyethylene monooleate; Polyoxyalkylene alkylamine compounds such as polyoxyethylene alkyl amine; sorbitan monolaurate, sorbitan monostearate, sorbitan trioleate, polyoxyethylene sorbitan monolaurate, sorbitan compounds such as polyoxyethylene sorbitan monooleate and the like.

  Examples of amphoteric surfactants include lauryl betaine and lauryl dimethylamine oxide.

These ion conductive additives may be used individually by 1 type, and may be used in combination of 2 or more type.
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, and 0.1 parts by mass or more and 5 parts by mass with respect to 100 parts by mass of the adhesive resin. It is more preferable that the amount is not more than parts.

The adhesive resin layer 40 can be formed, for example, by applying an adhesive coating solution on the antistatic layer 30.
As a method for applying the adhesive coating solution, a conventionally known coating method such as a roll coater method, a reverse roll coater method, a gravure roll method, a bar coat method, a comma coater method, a die coater method, or the like can be employed. Although there is no restriction | limiting in particular in the drying conditions of the apply | coated adhesive, Generally, it is preferable to dry for 10 second-10 minutes in the temperature range of 80-200 degreeC. More preferably, it is dried at 80 to 170 ° C. for 15 seconds to 5 minutes. In order to sufficiently promote the cross-linking reaction between the cross-linking agent and the (meth) acrylic pressure-sensitive adhesive resin, after the drying of the pressure-sensitive adhesive coating solution is completed, it may be heated at 40 to 80 ° C. for about 5 to 300 hours.

In the adhesive film 100 according to this embodiment, the thickness of the adhesive resin layer 40 is preferably 100 μm or less, more preferably 50 μm or less, further preferably less than 30 μm, still more preferably 25 μm or less, and further 20 μm. It is more preferable that it is less than 15 micrometers, and it is especially preferable that it is 15 micrometers or less. Thereby, the distance of the surface of the adhesive resin layer 40 and the antistatic layer 30 can be made small, As a result, the antistatic property of the adhesive film 100 can be made more favorable.
The lower limit value of the thickness of the adhesive resin layer 40 is not particularly limited, but is preferably 0.5 μm or more, more preferably 1.0 μm or more, further preferably 3.0 μm or more, from the viewpoint of improving the adhesive strength. 0 μm or more is particularly preferable.

(Antistatic layer)
The adhesive film 100 according to the present embodiment includes an 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 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 peeling.
Examples of the conductive polymer include a polythiophene conductive polymer, a polypyrrole conductive polymer, a polyaniline conductive polymer, a poly (p-phenylene vinylene) conductive polymer, and a polyquinoxaline conductive polymer. Etc.
A polythiophene-based conductive polymer is preferable from the viewpoint of a good balance of optical properties, appearance, antistatic properties, coating properties, stability, and the like. Examples of the polythiophene conductive polymer include polyethylene dioxythiophene and polythiophene.
These conductive polymers may be used individually by 1 type, and may be used in combination of 2 or more type.

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

Examples of the sulfonic acid compounds include p-toluenesulfonic acid, benzenesulfonic acid, ethylbenzenesulfonic acid, octylbenzenesulfonic acid, dodecylbenzenesulfonic acid, mesitylenesulfonic acid, m-xylenesulfonic acid, polystyrenesulfonic acid, and polyvinylsulfonic acid. Is mentioned. From the viewpoint of improving the solubility and water dispersibility of the conductive polymer, polystyrene sulfonic acid and polyvinyl sulfonic acid are preferred.
A sulfonic acid type compound may be used individually by 1 type, and may be used in combination of 2 or more type.

By adding the doping agent in this manner, 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. Further improvement.
The mixing ratio of the doping agent is, for example, 100 to 300 parts by mass with respect to 100 parts by mass of the conductive polymer.
As a combination of the conductive polymer and the doping agent, a combination of polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS) is preferable because of excellent antistatic properties.

The material constituting the antistatic layer 30 may further contain a binder resin from the viewpoint of improving film forming properties, adhesion, and the like.
Examples of the binder resin include polyurethane resin, polyester resin, (meth) acrylic resin, polyether resin, cellulose resin, polyvinyl alcohol resin, epoxy resin, polyvinyl pyrrolidone, polystyrene resin, polyethylene glycol, penta Erythritol and the like can be used Binder resins may be used alone or in combination of two or more. Content of binder resin is 10-500 mass parts with respect to 100 mass parts of conductive polymers, for example.

  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, and preferably 0.01 μm or more and 1 μm or less. Further preferred.

(Uneven absorbent resin layer)
The pressure-sensitive adhesive film 100 according to this embodiment includes a concavo-convex absorbent resin layer 20. Thereby, the unevenness absorbability of the adhesive film 100 as a whole is improved and follows the unevenness (including bump electrodes) on the circuit forming surface of the semiconductor wafer (that is, the circuit surface including the circuit pattern), and adheres to the circuit forming surface of the semiconductor wafer. The adhesiveness with the adhesive film 100 can be improved. Furthermore, it is possible to suppress the bump electrodes formed on the surface of the semiconductor wafer from being broken by an external force applied when processing the semiconductor wafer.

  In addition, the adhesive film 100 according to the present embodiment includes the unevenness-absorbing resin layer 20, thereby making it possible to reduce the thickness of the adhesive resin layer 40 while improving the unevenness-absorbing property of the adhesive film 100. 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 improved.

Density of the bumps absorbent resin layer 20, from the viewpoint of the balance between mechanical strength and conformity to irregularity, preferably 800~990kg / ^{m 3,} more preferably 830~980kg / ^{m 3,} is 850~970kg / ^{m 3} Further preferred.

Although the resin which comprises the uneven | corrugated absorbent resin layer 20 will not be specifically limited if uneven | corrugated absorbability is shown, For example, a thermoplastic resin can be used.
More specifically, olefin resins, ethylene / polar monomer copolymers, ABS resins, vinyl chloride resins, vinylidene chloride resins, (meth) acrylic resins, polyamide resins, fluorine resins, polycarbonate resins, polyester resins. Examples thereof include resins.
Among these, at least one selected from olefin resins and ethylene / polar monomer copolymers is preferable.

Examples of the olefin resin include linear low density polyethylene (LLDPE), low density polyethylene, high density polyethylene, polypropylene, ethylene and an α-olefin copolymer containing 3 to 12 carbon atoms and α-olefin. , Propylene / α-olefin copolymer containing propylene and C 4-12 α-olefin, ethylene / cyclic olefin copolymer, ethylene / α-olefin / cyclic olefin copolymer, and the like.
Examples of the ethylene / polar monomer copolymer include ethylene / (meth) ethyl acrylate copolymer, ethylene / (meth) methyl acrylate copolymer, ethylene / (meth) propyl propyl copolymer, ethylene / (meta ) Ethylene / unsaturated carboxylic acid ester copolymer such as butyl acrylate copolymer; ethylene / vinyl acetate copolymer, ethylene / vinyl propionate copolymer, ethylene / vinyl butyrate copolymer, ethylene / vinyl stearate Examples thereof include ethylene / vinyl ester copolymers such as copolymers.
The resin constituting the uneven absorbent resin layer 20 may be used alone or in combination of two or more.

  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, 1-hexene, and 4-methyl-1. -Pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene and the like are preferable, and propylene, 1-butene and the like are preferable.

  Among these, low density polyethylene; polypropylene; ethylene / propylene copolymer, ethylene / 1-butene copolymer, ethylene / propylene / α having 4 to 12 carbon atoms are excellent in terms of excellent conformity at the time of pasting. -Ethylene / α-olefin copolymer such as olefin terpolymer; Propylene / 1-butene / α-olefin terpolymer having 5 to 12 carbon atoms; Ethylene / vinyl acetate copolymer, etc. At least one selected from the group consisting of ethylene / propylene copolymer and ethylene / vinyl acetate copolymer is more preferable.

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

Further, when the height of the bump electrode provided on the circuit forming surface of the semiconductor wafer is H [μm] and the thickness of the uneven absorbent resin layer 20 is d [μm], H / d is 1 or less. Is more preferable, 0.85 or less is more preferable, and 0.7 or less is further preferable. The unevenness absorbability can be made better while the thickness of the adhesive film 100 is made thinner.
Although the minimum of H / d is not specifically limited, For example, it is 0.01 or more.
Here, the height of the bump electrode is generally 2 μm or more and 300 μm or less.

The adhesive film 100 which concerns on this embodiment may provide the contact bonding layer (not shown) between each layer. According to this adhesive layer, the adhesion between the layers can be improved.
Moreover, the adhesive film 100 which concerns on this embodiment may laminate | stack a release film further.

  Next, an example of the manufacturing method of the adhesive film 100 which concerns on this embodiment is demonstrated.

First, the uneven absorbent resin layer 20 is formed on one surface of the base material layer 10 by extrusion lamination. Next, a predetermined conductive material is applied on a separately prepared release film and dried to form an antistatic layer 30, and the antistatic layer 30 is laminated on the uneven absorbent resin layer 20. Next, a pressure-sensitive adhesive resin layer 40 is formed by applying a pressure-sensitive adhesive coating solution on the antistatic layer 30 and drying it, whereby the pressure-sensitive adhesive film 100 is obtained.
The base material layer 10 and the uneven absorbent resin layer 20 may be formed by coextrusion molding, or the film-like base material layer 10 and the film-like uneven absorbent resin layer 20 are laminated (laminated). May be formed.

2. Semiconductor Device Manufacturing Method Next, each step of the semiconductor device manufacturing method according to the present embodiment will be described.

(Process (A))
First, a structure including a semiconductor wafer having a circuit formation surface and an adhesive film 100 bonded to the circuit formation surface side of the semiconductor wafer is prepared.
For example, such a structure peels the release film from the adhesive resin layer 40 of the adhesive film 100 to expose the surface of the adhesive resin layer 40, and the semiconductor wafer is formed on the adhesive resin layer 40. It can be manufactured by attaching a circuit forming surface.

  Here, conditions for attaching the circuit forming surface of the semiconductor wafer to the adhesive film 100 are not particularly limited. For example, the temperature may be 30 to 80 ° C., and the pressure may be 0.05 to 0.5 MPa.

  The step (A) preferably further includes a step (A2) of producing a structure by heating and sticking the adhesive film 100 to the circuit forming surface of the semiconductor wafer. Thereby, the adhesion state of the adhesive resin layer 40 and the semiconductor wafer can be improved over a long period of time. Although it does not specifically limit as heating temperature, For example, it is 60-80 degreeC.

  The operation of adhering the adhesive film 100 to the semiconductor wafer may be performed manually, but can be generally performed by an apparatus called an automatic applicator to which a roll-shaped adhesive film is attached.

  Although it does not specifically limit as a semiconductor wafer which has a circuit formation surface, For example, the silicon wafer with which circuits, such as wiring, a capacitor, a diode, or a transistor were formed in the surface, a silicon carbide wafer, a compound semiconductor wafer, a sapphire wafer etc. are mentioned.

(Process (B))
Next, the surface opposite to the circuit forming surface side of the semiconductor wafer (hereinafter also referred to as a back surface) is back-ground.
Here, the back grinding means that the semiconductor wafer is thinned to a predetermined thickness without breaking or breaking the semiconductor wafer.
For example, the structure is fixed to a chuck table or the like of a grinding machine, and the back surface (circuit non-formed surface) of the semiconductor wafer is ground.

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

As the back surface grinding method, a known grinding method such as a through-feed method or an in-feed method is employed. Grinding is performed while cooling water over a semiconductor wafer and a grindstone.
After the back grinding, chemical etching is performed as necessary. Chemical etching adheres to an etching solution selected from the group consisting of acidic aqueous solutions made of hydrofluoric acid, nitric acid, sulfuric acid, acetic acid and the like alone or in a mixed solution, alkaline aqueous solutions such as potassium hydroxide aqueous solution and sodium hydroxide aqueous solution. It is performed by a method such as immersing a semiconductor wafer with the adhesive film 100 attached. The etching is performed for the purpose of removing distortion generated on the back surface of the semiconductor wafer, further thinning the wafer, removing an oxide film, etc., pretreatment when forming electrodes on the back surface, and the like. The etching solution is appropriately selected according to the above purpose.

(Process (C))
Next, after the adhesive film 100 is irradiated with ultraviolet rays, the adhesive film 100 is removed from the semiconductor wafer.
By irradiating the adhesive film 100 with ultraviolet rays, the adhesive resin layer 40 is photocured and the adhesive force of the adhesive resin layer 40 is reduced. Thereby, the adhesive film 100 can be peeled from the semiconductor wafer.
Ultraviolet rays are irradiated from the base material layer 10 side of adhesive film 100, for example.

Dose of ultraviolet irradiation against adhesive film 100 is preferably 300 mJ / cm ² or more, more preferably 350 mJ / cm ² or more, 500 mJ / cm ² or more is more preferable.
When the dose of ultraviolet rays is equal to or more than the lower limit, the adhesive strength of the adhesive resin layer 40 can be sufficiently reduced, and as a result, the occurrence of adhesive residue on the circuit forming surface of the semiconductor wafer is further suppressed. Can do.
Although not particularly limited upper limit of the dose of ultraviolet irradiation against adhesive film 100, from the viewpoint of productivity, for example, at 1500 mJ / cm ² or less, preferably 1200 mJ / cm ² or less.

After the adhesive film 100 is irradiated with ultraviolet rays to reduce the adhesive strength of the adhesive resin layer 40, the adhesive film 100 is peeled from the semiconductor wafer.
After grinding the back surface of the semiconductor wafer, a chemical etching process may be performed before the adhesive film 100 is peeled off. Moreover, after peeling of the adhesive film 100 as needed, processes, such as water washing and plasma washing | cleaning, are given with respect to the semiconductor wafer surface.

  Although peeling of the adhesive film 100 may be performed by hand, it can be generally performed by an apparatus called an automatic peeling machine.

  The surface of the semiconductor wafer after peeling off the adhesive film 100 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 may be used in combination. These cleaning methods are appropriately selected depending on the contamination state of the semiconductor wafer surface.

(Other processes)
After performing the steps (A) to (C), the semiconductor wafer may be diced into individual pieces to obtain a semiconductor chip, and the step of mounting the obtained semiconductor chip on a circuit board may be further performed. . These steps can be performed based on known information.

  As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and various structures other than the above are also employable.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited to this.

  Details of the materials used for the production of the adhesive film are as follows.

<Base material layer>
Polyethylene terephthalate film (thickness 50μm)

<Resin for forming concave and convex absorbent resin layer>
Concavity and convexity absorbent resin 1: Ethylene / vinyl acetate copolymer (density: 960 kg / m ³ , “Evaflex EV150” manufactured by Mitsui DuPont Polychemical Co., Ltd.)

<Material for forming antistatic layer>
Antistatic layer forming material 1: conductive material containing polyethylene dioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) (trade name: Denatron P-504CT, manufactured by Nagase ChemteX)

<Ion conductive additive>
Ion conductive additive 1: tetradecyl dimethyl benzyl ammonium chloride (manufactured by NOF Corporation, trade name: Nissan cation M ₂ -100)

<Photoinitiator>
Photoinitiator 1: Benzyldimethyl ketal (trade name: Irgacure 651, manufactured by BASF)

<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. The resultant was dropwise added to a nitrogen-substituted flask containing 20 parts by mass of toluene and 80 parts by mass of ethyl acetate with stirring at 85 ° C. over 5 hours, and further reacted by stirring for 5 hours. After completion of the reaction, this solution was cooled, and 10 parts by mass of toluene, 7 parts by mass of methacryloyloxyethyl isocyanate (manufactured by Showa Denko KK, product name: Karenz MOI), and 0.02 parts by mass of dibutyltin dilaurate were added. In addition, the reaction was carried out at 85 ° C. for 12 hours while blowing air to obtain a pressure-sensitive adhesive polymer 1 solution into which a polymerizable carbon-carbon double bond was introduced.
In this solution, 7 parts by mass of benzyl dimethyl ketal (manufactured by BASF Corp., Irgacure 651) as a photoinitiator with respect to 100 parts by mass of the copolymer (solid content), an isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals, Inc.) Product name: Olester P49-75S) 2 parts by mass Dipentaerythritol hexaacrylate (manufactured by Toagosei Co., Ltd.) as a low molecular weight compound having two or more polymerizable carbon-carbon double bonds in one molecule, product name: Aronix M-400) 12 parts by mass, ion-conductive additive 1: tetradecyl dimethyl benzyl ammonium chloride (manufactured by NOF CORPORATION, Nissan cation _M 2 -100) were added 0.5 part by weight, the adhesive resin layer A coating solution 1 was obtained.

<Coating liquid 2 for adhesive resin layer>
Except not adding the ion conductive additive 1, the coating liquid 2 for adhesive resin layers was obtained like the coating liquid 1 for adhesive resin layers.

<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 were mixed. This was dropped into a nitrogen-substituted flask containing 65 parts by mass of toluene and 50 parts by mass of ethyl acetate with stirring at 80 ° C. over 5 hours, and further reacted by stirring for 5 hours. After completion of the reaction, the solution was cooled, and 25 parts by mass of xylene, 2.5 parts by mass of acrylic acid, and ion conductive additive 1: tetradecyldimethylbenzylammonium chloride (Nissan Co., Ltd., Nissan Cation M) ₂ -100) 0.5 parts by weight was added, the air was 32 hours at 85 ° C. while blowing polymerizable carbon - to obtain a pressure-sensitive adhesive polymer 3 solution carbon double bond has been introduced.
In this solution, 7 parts by mass of benzyl dimethyl ketal (manufactured by BASF Corp., Irgacure 651) as a photoinitiator with respect to 100 parts by mass of the copolymer (solid content), an isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals, Inc.) Product name: Olester P49-75S) 2 parts by mass Dipentaerythritol hexaacrylate (manufactured by Toagosei Co., Ltd.) as a low molecular weight compound having two or more polymerizable carbon-carbon double bonds in one molecule, product name: Aronix M-400) 12 parts by mass was added to obtain a coating solution 3 for an adhesive resin layer.

[Example 1]
On the polyethylene terephthalate film used as the base material layer, the uneven absorbent resin 1 used as the uneven absorbent resin layer was extruded and laminated to a thickness of 195 μm to obtain a two-layer laminated film.
Next, the antistatic layer-forming material 1 is applied on a separately prepared release film and dried to form an antistatic film, and this antistatic film is laminated on the concavo-convex absorbent resin layer. An antistatic layer having a thickness of 0.1 μm was formed.
Subsequently, after apply | coating the coating liquid 2 for adhesive resin layers on the antistatic layer of the obtained laminated | multilayer film, it was made to dry and the 10-micrometer-thick adhesive resin layer was formed, and the adhesive film was obtained.
The following evaluation was performed about the obtained adhesive film. The obtained results are shown in Table 1.

[Examples 2-6, Comparative Examples 1-3]
Adhesion in the same manner as in Example 1 except that the presence or absence of the antistatic layer and the uneven absorbent resin layer, the thickness of the adhesive resin layer, the type of coating solution for the adhesive resin layer, etc. were changed as shown in Table 1. Each of the conductive films was produced.
The following evaluation was performed about the obtained adhesive film, respectively. The obtained results are shown in Table 1, respectively.

<Evaluation>
(1) Measurement of saturation band voltage The adhesive resin layer in the adhesive film is irradiated with ultraviolet light having a main wavelength of 365 nm using a high pressure mercury lamp (UVX-02528S1AJA02 manufactured by USHIO INC.) In an environment of 25 ° C. / cm was ² UV dose 1080MJ / cm ² irradiation by light curing the adhesive resin layer. Next, using a Static Honest Meter H-0110-S4 manufactured by Sicid Electrostatic Co., Ltd. as a measuring device, the surface of the adhesive resin layer was applied under conditions of an applied voltage of 10 kV, a distance between the sample and the electrode of 20 mm, 25 ° C., and 50% RH. The voltage was applied for 30 seconds, and the saturation voltage (V ₁ ) and the half life of the saturation voltage V _{1 on} the surface of the adhesive resin layer were calculated according to JIS L1094.
In addition, the saturation voltage of the surface of the adhesive resin layer and the half-life of the saturation voltage were changed in the same procedure as the measurement of the saturation voltage (V ₁ ) except that the amount of ultraviolet rays was changed to 200 to 540 mJ / cm ^2. Each was measured.

(2) Measurement of tack force The adhesive resin layer of the adhesive film is bonded to a polyimide film (product name: Kapton 200H, manufactured by Toray DuPont), and the substrate layer side of the adhesive film in an environment of 25 ° C Then, the pressure-sensitive adhesive resin layer was photocured by irradiating ultraviolet rays having a main wavelength of 365 nm with an irradiation intensity of 100 mW / cm ² and an ultraviolet ray amount of 1080 mJ / cm ² using a high-pressure mercury lamp. Subsequently, the polyimide film is peeled off from the adhesive film, and a probe tack tester (“TESTING MACHINES Inc. probe tack tester: Model 80-02-01”) is used as a measuring device, and a probe having a diameter of 5 mm and an adhesive resin are used. The surface of the layer was brought into contact with the surface at a speed of 10 mm / second, contacted with a contact load of 0.98 N / cm ² for 10 seconds, and then the probe was peeled off from the surface of the adhesive resin layer in the vertical direction at a speed of 10 mm / second. Thus, the tack force on the surface of the adhesive resin layer was measured.
Moreover, the tack force on the surface of the adhesive resin layer was measured in the same procedure as the above-described tack force measurement except that the amount of ultraviolet rays was changed to 200 to 540 mJ / cm ² .

(3) Evaluation of antistatic property The antistatic property of the adhesive film was evaluated according to the following criteria.
A: Saturation voltage V ₁ is 2.0 kV or less, and half-life of saturation voltage V ₁ is 30 seconds or less A: Saturation voltage V ₁ is 2.5 kV or less, and saturation band The half-life of the voltage V ₁ is 50 seconds or less. O: The saturation band voltage V ₁ is 3.0 kV or less and the half-life of the saturation band voltage V ₁ is 100 seconds or less. ₁ exceeds 3.0 kV, or the half-life of the saturation voltage V ₁ exceeds 100 seconds

(4) Evaluation of adhesiveness to semiconductor wafer surface The adhesiveness to the semiconductor wafer surface was evaluated according to the following criteria.
◯: The tack force of the adhesive resin layer not irradiated with ultraviolet rays (that is, the ultraviolet ray amount of 0 mJ / cm ² ) is 10 N / cm ² or more. X: The tack force of the adhesive resin layer not irradiated with the ultraviolet rays amount Is less than 10 N / cm ²

(5) Evaluation of contamination resistance to the semiconductor wafer surface The contamination resistance to the semiconductor wafer surface was evaluated according to the following criteria.
◯: The tack force of the adhesive resin layer photocured by irradiation with an ultraviolet ray amount of 1080 mJ / cm ² is 0.1 N / cm ² or less ×: The tack force of the adhesive resin layer photocured by irradiation with an ultraviolet ray amount of 1080 mJ / cm ² Exceeds 0.1 N / cm ²

(6) Evaluation of unevenness absorbency ○: When the bump electrode is attached to the bump electrode forming surface of the semiconductor wafer having the bump electrode, the bump electrode is not cracked and the adhesiveness with the semiconductor wafer is good. Bump electrode breaks when it is attached to the bump electrode forming surface of a semiconductor wafer having a defect, or the adhesion with the semiconductor wafer is poor. Bump height is 80 μm, bump pitch is 300 μm, bump is evaluated A bumped semiconductor wafer with 150 μm diameter bumps was used, and the adhesive film was attached using a roll laminator (product name: DR3000II manufactured by Nitto Seiki Co., Ltd.), roll speed: 2 mm / second, roll pressure: 0.4 MPa The table temperature was 80 ° C., and the unevenness absorbability after application was evaluated using an optical microscope.

The adhesive films of Examples 1 to 6 comprising the base material layer, the uneven absorbent resin layer, the antistatic layer, and the adhesive resin layer in this order are adhesive to the semiconductor wafer surface and stain resistant. In addition to excellent balance, the absorptivity to the irregularities on the surface of the semiconductor wafer and the antistatic property were also excellent. That is, according to the adhesive film 100 according to the present embodiment, a semiconductor device that has excellent absorbability with respect to the irregularities on the surface of the semiconductor wafer and that can suppress the amount of static electricity that is generated when peeling from the semiconductor wafer, and that has excellent quality. It can be understood that it can be obtained stably.
On the other hand, the adhesive films of Comparative Examples 1 and 2 that did not have an antistatic layer were inferior in antistatic properties. Moreover, the adhesive film of the comparative example 3 which is not equipped with an uneven | corrugated absorbent resin layer was inferior to uneven | corrugated absorbability.

DESCRIPTION OF SYMBOLS 10 Base material layer 20 Concavity and convexity absorptive resin layer 30 Antistatic layer 40 Adhesive resin layer 100 Adhesive film

Claims (12)

Preparing a structure including a semiconductor wafer having a circuit forming surface and an adhesive film bonded to the circuit forming surface side of the semiconductor wafer (A);
Back grinding the surface of the semiconductor wafer opposite to the circuit forming surface (B),
Removing the adhesive film from the semiconductor wafer after irradiating the adhesive film with ultraviolet rays (C);
A method for manufacturing a semiconductor device comprising at least
As the adhesive film,
Adhesive provided with a base material layer, a concave-convex absorbent resin layer, an antistatic layer, and an adhesive resin layer in this order, and used so that the adhesive resin layer is on the circuit forming surface side of the semiconductor wafer For manufacturing a semiconductor device using a conductive film. In the manufacturing method of the semiconductor device according to claim 1,
A method of manufacturing a semiconductor device, wherein a bump electrode is formed on the circuit forming surface of the semiconductor wafer. In the manufacturing method of the semiconductor device according to claim 2,
In the step (A), the method of manufacturing a semiconductor device further includes a step (A2) of manufacturing the structure by heating and sticking the adhesive film to the circuit forming surface of the semiconductor wafer. In the manufacturing method of the semiconductor device according to claim 2 or 3,
A method for manufacturing a semiconductor device, wherein H / d is 0.01 to 1 when a height of the bump electrode is H [μm] and a thickness of the uneven absorbent resin layer is d [μm]. In the manufacturing method of the semiconductor device according to any one of claims 1 to 4,
The manufacturing method of the semiconductor device whose thickness of the said adhesive resin layer is less than 30 micrometers. In the manufacturing method of the semiconductor device according to any one of claims 1 to 5,
The manufacturing method of the semiconductor device whose thickness of the said uneven | corrugated absorptive resin layer is 10 micrometers or more and 500 micrometers or less. In the manufacturing method of the semiconductor device according to claim 1,
The manufacturing method of the semiconductor device in which the said adhesive resin layer contains an ion conductive additive. In the manufacturing method of the semiconductor device according to claim 7,
The said ion conductive additive is a manufacturing method of the semiconductor device containing 1 type, or 2 or more types selected from a cationic surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant, and an ionic liquid. In the manufacturing method of the semiconductor device according to claim 1,
The method of manufacturing a semiconductor device, wherein the adhesive resin layer includes an ultraviolet curable adhesive resin. In the manufacturing method of the semiconductor device according to any one of claims 1 to 9,
In the step (C), the adhesive film is photocured by irradiating the adhesive film with ultraviolet rays having a dose of 300 mJ / cm ² or more, thereby reducing the adhesive force of the adhesive resin layer. And then, removing the adhesive film from the semiconductor wafer. In the manufacturing method of the semiconductor device according to any one of claims 1 to 10,
Is measured by the following methods, the production method of the saturated charging voltage V ₁ of the said adhesive resin layer surface after UV curing semiconductor device is less than 2.5 kV.
(Method)
The adhesive resin layer is photocured by irradiating ultraviolet light having a main wavelength of 365 nm with an irradiation intensity of 100 mW / cm ² and an ultraviolet light amount of 1080 mJ / cm ² using a high-pressure mercury lamp in an environment of 25 ° C. Let Next, 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 adhesive resin layer according to JIS L1094. The saturation voltage (V ₁ ) of the surface of is calculated. In the manufacturing method of the semiconductor device according to any one of claims 1 to 11,
The manufacturing method of the semiconductor device whose tack force of the surface of the said adhesive resin layer after ultraviolet curing measured by the following method is 0.1 N / cm < ² > or less.
(Method)
The adhesive resin layer of the adhesive film is bonded to a polyimide film, and an ultraviolet ray having a main wavelength of 365 nm is irradiated from a substrate layer side of the adhesive film under an environment of 25 ° C. with an irradiation intensity of 100 mW. / cm ² UV dose 1080MJ / cm ² irradiated to photocuring of the adhesive resin layer. Next, the polyimide film is peeled from the adhesive film, and a probe tack tester is used as a measuring device to bring the probe having a diameter of 5 mm into contact with the surface of the adhesive resin layer at a rate of 10 mm / second, and 0.98 N Measure the tack force on the surface of the adhesive resin layer by peeling the probe from the surface of the adhesive resin layer in the vertical direction at a speed of 10 mm / second after contacting with a contact load of 10 cm / cm ² for 10 seconds. To do.

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