JP6950907B2 - Manufacturing method of semiconductor devices - Google Patents

Description

The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a method for manufacturing a semiconductor device using a semiconductor chip in which at least the bump surface is protected by a protective film.

Conventionally, semiconductor devices have been manufactured by using a mounting method called a face-down method. In the face-down method, an electrode portion called a bump is formed on the surface of the semiconductor chip, and the semiconductor chip is mounted on the substrate so that the chip surface faces the substrate or the like.
In semiconductor wafers and semiconductor chips used in the face-down method, resin layers having various functions may be provided on the surface of the wafer on which bumps are provided for various purposes. Further, when the back surface of a semiconductor wafer is ground, a back grind sheet is generally attached to protect the surface of the wafer. Therefore, conventionally, a laminated sheet in which a back grind sheet and various resin layers are laminated and integrated may be used.

In Patent Document 1, as such a laminated sheet, a thermosetting resin layer in contact with a circuit surface, a flexible thermoplastic resin layer directly laminated on the layer, and a thermoplastic resin layer on the thermoplastic resin layer. Further, those provided with an outermost layer that is laminated and made of a resin film or the like are disclosed. This laminated sheet is attached to the semiconductor wafer at the time of backside grinding to protect the semiconductor wafer. Further, after the back surface grinding, the thermoplastic resin layer and the outermost layer are peeled off from the thermosetting resin layer, while the semiconductor chip is mounted on the substrate of the thermosetting resin layer remaining on the semiconductor wafer. It is later cured and used as a sealing resin.

Japanese Unexamined Patent Publication No. 2005-28734

By the way, the bumps provided on the surface of the wafer are liable to be damaged because stress is concentrated on the bump neck which is a connecting portion between the semiconductor wafer and the bumps. Therefore, it has been studied to form a protective film on the wafer surface separately from the sealing resin. It has been studied to form a protective film by heat-curing a thermosetting resin layer laminated on a wafer surface, for example, before sealing the resin.
However, while the thermosetting resin is fluidized by heating, the flow of the resin is obstructed by bumps, so that it may be difficult to obtain a uniform film thickness. If the film thickness of the protective film cannot be made uniform, the embedding property of the bump neck becomes insufficient, and the bump neck may not be properly protected.

The present invention has been made in view of the above problems, and an object of the present invention is to ensure embedding of a bump neck by a protective film having a uniform film thickness in a semiconductor wafer with bumps. Provided is a method for manufacturing a semiconductor device capable of appropriately protecting the above.

The present inventors have bonded a thermosetting resin layer supported by a support sheet on the surface (bump surface) of a semiconductor wafer provided with bumps, and are thermosetting in a state of being supported by the support sheet. We have found that by curing the resin layer, the fluidity of the thermosetting resin during heat curing can be suppressed and the thickness of the resin layer can be kept uniform, and the following invention has been completed. The present invention provides the following (1) to (8).
(1) (I) A film for forming a first protective film in which a first support sheet and a thermosetting resin layer are provided in this order on the surface of a semiconductor wafer provided with bumps, the thermosetting resin layer. And the process of pasting together
(II) A step of heating and curing the thermosetting resin layer to form a protective film, and
(III) A step of peeling the first support sheet from the protective film formed by curing the thermosetting resin layer.
(IV) A step of dicing the semiconductor wafer together with the protective film, and
A method for manufacturing a semiconductor device.
(2) (A-1) The step of bonding the second protective film forming layer to the back surface of the semiconductor wafer, and
(A-2) The step of heating the second protective film forming layer to form the second protective film and (A-3) The second protective film forming layer or the second protection on the back surface of the semiconductor wafer. The method for manufacturing a semiconductor device according to (1) above, further comprising a step of laminating a second support sheet on the film.
(3) (B-1) A second protective film forming film including a second supporting sheet and a second protective film forming layer provided on the second supporting sheet, and the second protective film forming layer. The process of bonding to the back surface of the semiconductor wafer and the process of bonding to the back surface of the semiconductor wafer.
(B-2) The method for manufacturing a semiconductor device according to (1) above, further comprising a step of heating the second protective film forming layer to form the second protective film.
(4) The method for manufacturing a semiconductor device according to (2) or (3) above, wherein the thermosetting resin layer and the second protective film forming layer are simultaneously heated and heat-cured.
(5) The method for manufacturing a semiconductor device according to any one of (1) to (4) above, wherein the adhesive force after heating in the step (II) of the first support sheet is less than 10 N / 25 mm.
(6) The first support sheet includes a first base material and a first pressure-sensitive adhesive layer provided on one surface of the first base material, and is thermoset on the first pressure-sensitive adhesive layer. The method for manufacturing a semiconductor device according to any one of (1) to (5) above, wherein the sex resin layer is provided.
^{(7) The melt viscosity of the thermosetting resin layer is 1 × 10 2} Pa · S or more ^{and less than 2 × 10 4} Pa · S at the temperature at which the first protective film forming film is attached to the semiconductor wafer. And
^{The shear modulus of the first pressure-sensitive adhesive layer is 1 × 10 3} Pa or more and 2 × 10 ⁶ Pa or less at the temperature at which the first protective film forming film is attached to the semiconductor wafer (6). The method for manufacturing a semiconductor device according to.
(8) The method for manufacturing a semiconductor device according to any one of (1) to (7) above, wherein the thermosetting resin layer has a thickness of 0.01 to 0.99 times the bump height.

The present invention provides a method for manufacturing a semiconductor device capable of appropriately protecting bumps by the protective film by making the film thickness of the protective film uniform and embedding a bump neck inside the protective film.

It is a schematic cross-sectional view which shows the semiconductor wafer which bump was formed on the surface. It is a schematic cross-sectional view which shows the film for forming the 1st protective film. It is a schematic cross-sectional view which shows the process of heating a semiconductor wafer to which the film for forming the 1st protective film is attached. It is a schematic cross-sectional view which shows the semiconductor wafer after the 1st support sheet is peeled off. It is a schematic cross-sectional view which shows the semiconductor wafer when dicing is performed. It is a schematic cross-sectional view which shows the state when the fragmented semiconductor chip is placed on the substrate for mounting a chip. FIG. 5 is a schematic cross-sectional view showing a semiconductor wafer in which a protective film is formed on the front surface and a second protective film forming layer is laminated on the back surface. It is a schematic diagram which shows the process of dicing a semiconductor wafer which formed the protective film and the 2nd protective film on the front surface and the back surface respectively. It is a schematic diagram which shows the process of heating a semiconductor wafer in which the 1st protective film forming film and the 2nd protective film forming layer are laminated on the front surface and the back surface respectively. It is a schematic cross-sectional view which shows the film for forming the 2nd protective film. It is a schematic cross-sectional view which shows the semiconductor wafer which the protective film is formed on the front surface, and the 2nd protective film formation film is bonded on the back surface. It is a schematic diagram which shows the process of heating the semiconductor wafer which provided the 1st protective film forming film and the 2nd protective film forming film on the front surface and the back surface respectively.

Hereinafter, the present invention will be specifically described with reference to embodiments.
(First Embodiment)
As shown in FIG. 1, the semiconductor wafer 10 used in the present manufacturing method is a bumped wafer in which bumps 11 are provided on the surface 10A. A plurality of bumps 11 are usually provided. The semiconductor wafer 10 is not particularly limited, but may be a silicon wafer, or may be a ceramic, glass, sapphire-based wafer, or the like. The thickness of the semiconductor wafer 10 is not particularly limited, but is preferably 0.625 to 0.825 mm. The material of the bump 11 is not particularly limited, and various metal materials are used, and solder is preferably used. The shape of the bump 11 is not particularly limited and may be round as shown in FIG. 1, but any other shape may be used. The height of the bump 11 is not particularly limited, but is usually 5 to 1000 μm, preferably 50 to 500 μm.

The method for manufacturing a semiconductor device according to the first embodiment of the present invention has at least the following steps.
(I) A film for forming a first protective film in which a first support sheet and a thermosetting resin layer are provided in this order on the surface of a semiconductor wafer provided with bumps, and a surface on which the thermosetting resin layer is bonded. The process of pasting together,
(II) A process of heating and curing a thermosetting resin layer to form a protective film.
(III) A step of peeling the first support sheet from the protective film formed by curing the thermosetting resin layer.
(IV) Step of dicing a semiconductor wafer together with a protective film

Hereinafter, the manufacturing method of this embodiment will be described in detail for each step.
[Step (I)]
In the step (I), first, as shown in FIG. 2, the first protective film forming film 20 including the first support sheet 23 and the thermosetting resin layer 25 provided on the first support sheet 23. Prepare. Then, as shown in FIG. 3, the first protective film forming film 20 is bonded to the surface (bump surface) 10A of the semiconductor wafer 10 with the thermosetting resin layer 25 as the bonding surface.
Here, in the first protective film forming film 20, as shown in FIG. 2, the first support sheet 23 is provided on one surface of the first base material 21 and the first base material 21. The agent layer 22 may be provided and the thermosetting resin layer 25 may be attached on the first pressure-sensitive adhesive layer 22, but the first pressure-sensitive adhesive layer 22 is omitted and is placed on the first base material 21. The thermosetting resin layer 25 may be directly attached. Further, one surface of the first base material 21 is surface-treated, or a layer other than the adhesive layer is provided on the first support sheet 23, and the thermosetting resin layer 25 is provided via the layer or the surface-treated surface. It may be affixed. Further, an intermediate layer may be provided between the first pressure-sensitive adhesive layer 22 and the first base material 21.

Further, a release material (not shown) may be further attached on the thermosetting resin layer 25 of the first protective film forming film 20. The release material protects the thermosetting resin layer 25 until the time when the first protective film forming film 20 is used. The release material is removed by peeling off the first protective film forming film 20 from the first protective film forming film 20 before the first protective film forming film 20 is attached to the semiconductor wafer 10.
The first pressure-sensitive adhesive layer 22 is formed of various types of pressure-sensitive adhesives, but even if it is formed of an energy-ray-curable pressure-sensitive adhesive that is cured by irradiating with energy rays to reduce the adhesive force to the adherend. good.

The first support sheet 23 preferably has heat resistance. That is, the first base material 21 constituting the first support sheet 23 is preferably a base material that does not melt or shrink significantly due to the heating in step (II). Further, the first support sheet 23 having heat resistance does not have high adhesiveness to the adherend even if it is heated for a predetermined time. Specifically, the heat-resistant first support sheet 23 has an adhesive force of less than 10 N / 25 mm after heating in step (II). Further, the adhesive force of the first support sheet 23 after heating in the step (II) is 0.3 to 9.8 N / 25 mm in order to make the adhesive force to the first protective film 25A after heating more appropriate. It is preferable, and 0.5 to 9.5 N / 25 mm is more preferable.

The adhesive strength after heating means that when the pressure-sensitive adhesive layer is formed of an energy ray-curable pressure-sensitive adhesive, the pressure-sensitive adhesive layer is irradiated with energy rays at the same timing and conditions as the manufacturing method to be carried out. It means the adhesive force when the pressure-sensitive adhesive layer is heated under the same timing and conditions as the manufacturing method to be carried out. In the manufacturing method to be carried out, for example, when the energy rays are irradiated after the heating in the step (II), the values are the values when the pressure-sensitive adhesive layer is irradiated with the energy rays after the heating and the adhesive strength is measured. On the other hand, in the manufacturing method to be carried out, for example, when the energy rays are irradiated before the heating in the step (II), the values when the energy rays are irradiated to the pressure-sensitive adhesive layer and the adhesive strength is measured before the heating are used. be. Further, the heating of the first support sheet at the time of measuring the adhesive force is performed in a state where the first support sheet is attached to the thermosetting resin layer which is an adherend, and the thermosetting resin layer is cured by the heating. It serves as a protective film. Details of the method for measuring the adhesive strength are as described in Examples.

The bonding of the first protective film forming film 20 to the semiconductor wafer 10 is preferably performed at a bonding temperature of 30 to 150 ° C., and more preferably 40 to 100 ° C.
Further, the first protective film forming film 20 is preferably attached while being pressed, for example, by pressing with a pressing means such as a pressure-bonding roller. Alternatively, the first protective film forming film 20 may be pressure-bonded to the semiconductor wafer 10 by a vacuum laminator.

When the first protective film forming film 20 is attached to the semiconductor wafer 10, the bumps 11 penetrate the thermosetting resin layer 25 and project toward the first support sheet 23, as shown in FIG. By projecting the bump 11 toward the first support sheet 23 in this way, it becomes easy to bring the bump 11 into contact with an electrode or the like on the chip mounting substrate and fix it by reflow described later.
However, the bump 11 may be in a state of being embedded inside the thermosetting resin layer 25 without protruding toward the first support sheet 23 side. Even in such a state, in the step (II) or the like, the thermosetting resin layer 25 may be allowed to flow by heating to project the bump 11.

The first support sheet 23 includes a base material 21 and a first pressure-sensitive adhesive layer 22 provided on one surface of the base material 21, and a thermosetting resin layer 25 is provided on the first pressure-sensitive adhesive layer 22. ^{If so, the melt viscosity of the thermosetting resin layer 25 is 1 × 10 2} Pa · S or more 2 × 10 at the temperature (bonding temperature) when the first protective film forming film 20 is bonded to the semiconductor wafer 10. ^{It is preferably less than 4} Pa · S and the shear modulus of the first pressure-sensitive adhesive layer 22 is 1 × 10 ³ Pa or more and 2 × 10 ⁶ Pa or less at the bonding temperature. Further, the melt viscosity of the thermosetting resin layer 25 is ^{1 × 10 3 Pa · 1 ×} 10 4 Pa · less S or S, the shear modulus of the first adhesive layer 22, 1 × 10 ⁴ Pa or more 5 It is more preferable that it is × 10 ^{5 Pa or less.}
By setting the shear modulus of the first pressure-sensitive adhesive layer 22 and the melt viscosity of the thermosetting resin layer 25 within the above ranges at the bonding temperature, the bump neck, which is the root portion of the bump 11, is formed by the thermosetting resin layer. The tip of the bump 11 is easily projected from the thermosetting resin layer 25 while being embedded by the 25. Further, it also prevents the thermosetting resin layer 25 from flowing too much during heating in the step (II) described later.

The melt viscosity of the thermosetting resin layer 25 can be adjusted, for example, by changing the blending amount of each material in the thermosetting resin composition described later and the type of each material. Further, the shear elastic modulus of the first pressure-sensitive adhesive layer 22 can be adjusted by changing the type of pressure-sensitive adhesive. Further, when the first pressure-sensitive adhesive layer 22 is formed of an energy ray-curable pressure-sensitive adhesive, the first pressure-sensitive adhesive layer 22 is partially or partially irradiated with energy rays before the first support sheet 33 is attached to the semiconductor wafer 10. It is also possible to adjust the shear modulus by completely curing.

The melt viscosity of the thermosetting resin layer is a value measured by a parallel plate method using a rheometer (manufactured by HAAKE, RS-1). More specifically, it is a value when the measurement is performed in the range of room temperature to 250 ° C. under the conditions of a gap of 100 μm, a rotating cone diameter of 20 mm, and a rotating speed of 10 s- ^1.
The shear elastic modulus of the pressure-sensitive adhesive layer was measured by forming a pressure-sensitive adhesive layer having a thickness of 0.2 mm and using a shear elastic modulus measuring device (ARES manufactured by Leometric Co., Ltd.). Specifically, the shear modulus was measured under the conditions of a frequency of 1 Hz, a plate diameter of 7.9 mmφ, and a strain of 1%, with the temperature set to the same temperature as the bonding temperature. If the pressure-sensitive adhesive layer is cured by energy rays at the time of bonding, the pressure-sensitive adhesive layer is cured under the same conditions and the shear modulus is measured.

The thermosetting resin layer 25 preferably has a thickness of 0.01 to 0.99 times the height of the bump 11 (bump height). By setting the thickness of the thermosetting resin layer 25 to 0.01 times or more the bump height, it becomes easy to embed the bump neck inside the protective film and prevent the bump neck from being damaged. Further, by setting the value to 0.99 times or less, the tip of the bump can be easily projected from the thermosetting resin layer 25. From these viewpoints, it is more preferable that the thermosetting resin layer 25 has a thickness of 0.1 to 0.9 times the bump height.
The thickness of the thermosetting resin layer 25 is not particularly limited, but is usually 5 to 500 μm, preferably 10 to 100 μm.

[Process (II)]
After the above step (I), the thermosetting resin layer 25 laminated on the surface 10A of the semiconductor wafer 10 is heated (step (II)). As shown in FIG. 3, this heating is performed by heating the semiconductor wafer 10 on which the first protective film forming film 20 (that is, the first support sheet 23 and the thermosetting resin layer 25) is laminated, for example, in a heating furnace or the like. It is preferable to place it inside the oven and heat it. Since the thermosetting resin layer 25 contains a thermosetting resin, it is heat-cured by the above heating to form a protective film 25A (see FIG. 4).
The heating conditions are not particularly limited as long as the thermosetting resin contained in the thermosetting resin layer 25 is cured. For example, the temperature is 80 to 200 ° C. for 30 to 300 minutes, preferably 100 to 180 ° C. It is carried out for 60 to 200 minutes.

[Process (III)]
After the heating in the step (II), in the step (III), the first support sheet 23 attached to the surface of the semiconductor wafer 10 is peeled off from the protective film 25A. After this peeling, the protective film 25A remains on the semiconductor wafer 10 as shown in FIG.
Here, when the first support sheet 23 has heat resistance as described above, the adhesive force to the protective film 25A does not significantly improve even if it is heated. Therefore, the first support sheet 23 can be easily peeled off from the protective film 25A even after the heating in step (II).

When the first pressure-sensitive adhesive layer 22 is formed of an energy ray-curable pressure-sensitive adhesive, the first pressure-sensitive adhesive layer 22 is irradiated with energy rays before the first support sheet 23 is peeled from the semiconductor wafer 10 in step (III). The first pressure-sensitive adhesive layer 22 is cured. Since the first pressure-sensitive adhesive layer 22 is cured by irradiation with energy rays, the adhesive strength is reduced, so that the first pressure-sensitive adhesive layer 22 can be easily peeled off at the interface with the thermosetting resin layer 25.
The timing of irradiating the first pressure-sensitive adhesive layer 22 with energy rays to cure the first pressure-sensitive adhesive layer 22 is not particularly limited, and the first support sheet 23 may be cured in advance before being attached to the semiconductor wafer. Further, it may be after being attached to the semiconductor wafer 10, and may be performed, for example, between the steps (II) and the steps (III). Further, for example, before the first support sheet 23 is attached to the semiconductor wafer 10, the first adhesive layer 22 is irradiated with energy rays to such an extent that it is not completely cured to reduce the adhesive force and is attached to the semiconductor wafer 10. After that, it may be further irradiated with energy rays to further cure it, and the adhesive strength may be further reduced.

[Process (IV)]
Next, as shown in FIG. 5, the semiconductor wafer 10 in which the protective film 25A is formed on the bump surface is divided by dicing and separated into a plurality of semiconductor chips 15. In this step, along with the semiconductor wafer 10, the protective film 25A is also divided according to the shape of the semiconductor chip 15.
The dicing method is not particularly limited, but known methods such as blade dicing, stealth dicing, and laser dicing can be used. For example, by providing a notch 17 so as to penetrate the protective film 25A and the semiconductor wafer 10. It is what you do.
For dicing, for example, as shown in FIG. 5, a second support sheet 33 is attached to the back surface 10B side of the semiconductor wafer 10 to support the semiconductor wafer 10, and a notch 17 is made from the front surface 10A side of the semiconductor wafer 10. Do it with.

In the configuration of FIG. 5, the second support sheet 33 includes a second base material 31 and a second pressure-sensitive adhesive layer 32 provided on one surface of the second base material 31, and is provided with a second pressure-sensitive adhesive. It is attached to the semiconductor wafer 10 via the agent layer 32. However, in the second support sheet 33, the second pressure-sensitive adhesive layer 32 may be omitted, and the surface of the second base material 31 on the side to be adhered to the semiconductor wafer 10 is surface-treated or the pressure-sensitive adhesive layer. A layer other than the pressure-sensitive adhesive layer may be provided instead of the pressure-sensitive adhesive layer, and may be bonded to the back surface side of the semiconductor wafer 10 via the layer or the surface-treated surface. Further, an intermediate layer (not shown) may be further provided between the second pressure-sensitive adhesive layer 32 and the second base material 31.
The second support sheet 33 is one size larger than the semiconductor wafer 10, and its central region is attached to the semiconductor wafer 10, and the outer peripheral region is not attached to the semiconductor wafer 10 but is attached to the support member 13. preferable. The support member 13 is a member for supporting the second support sheet 33 at the time of dicing or the like, and examples thereof include a ring frame.
It is not necessary to directly attach the second pressure-sensitive adhesive layer 32 to the support member 13 of the second support sheet 33, and a re-peelable adhesive layer or the like is provided in the outer peripheral region of the second support sheet 33. It may be attached by a removable adhesive layer or the like.

The second pressure-sensitive adhesive layer 32 is formed of various pressure-sensitive adhesives, but may be formed of an energy ray-curable pressure-sensitive adhesive. When it is formed by an energy ray-curable pressure-sensitive adhesive, energy rays are preliminarily formed in a region (central region) bonded to the back surface side of the semiconductor wafer 10 of the second pressure-sensitive adhesive layer 32 before pickup described later. Is applied to cure the second pressure-sensitive adhesive layer 32 to reduce the adhesive force to the back surface of the semiconductor wafer 10. The timing of irradiating the energy rays is not particularly limited, but may be performed before bonding to the semiconductor wafer 10 or after dicing and before pickup.
On the other hand, the outer peripheral region does not need to be irradiated with energy rays, and the adhesive strength may be maintained high for the purpose of adhering to the support member 13.

In the present embodiment, after dicing, the semiconductor chip 15 is picked up, attached to a chip mounting substrate or the like by reflow, and then the gap between the semiconductor chip 15 and the chip mounting substrate is further sealed with a sealing resin. A semiconductor device is manufactured by going through necessary steps such as.
Here, the pick-up method is not particularly limited, but for example, the semiconductor chip 15 is pushed up from the back surface side by a pin or the like via the second support sheet 33, and the semiconductor chip 15 is peeled off from the second support sheet 33 to form a vacuum collet. There is a method of picking up by such means.

The picked up semiconductor chip 15 is attached to a chip mounting substrate or the like by, for example, the following method.
That is, as shown in FIG. 6, the semiconductor chip 15 is arranged at a predetermined position on the chip mounting substrate 40 so that its surface (that is, the bump surface) faces the chip mounting substrate 40. Then, the bump 11 is fixed to the chip mounting substrate 40 by reflow, and the semiconductor chip 15 and the chip mounting substrate 40 are electrically conductive. In reflow, for example, a conductive material (not shown) such as solder provided on the substrate 40 is melted, and the bump 11 is fused to an electrode or the like of the chip mounting substrate 40 by the conductive material.
The reflow is performed by, for example, arranging the chip mounting substrate 40 and the semiconductor chip 15 arranged on the substrate 40 inside the heating furnace and heating them. The heating in the reflow is performed, for example, in an atmosphere of 120 to 300 ° C. for 0.5 to 5 minutes, preferably in an atmosphere of 160 to 260 ° C. for 1 to 2 minutes.

In the manufacturing method of the present embodiment, it is preferable that the semiconductor wafer 10 is back-ground. The back surface grinding is performed in a state where the first support sheet 23 is attached to the surface 10A side of the semiconductor wafer 10. That is, the back surface grinding of the semiconductor wafer is performed between the step (I) and the step (III). As a result, the first support sheet 23 is used not only as a sheet for supporting the thermosetting resin layer 25, but also as a background sheet for protecting the bump surface during backside grinding. Further, the back surface grinding of the semiconductor wafer 10 is preferably performed between the steps (I) and the steps (II).
The back surface grinding of the semiconductor wafer is performed, for example, by fixing the front surface side of the semiconductor wafer 10 to which the first support sheet 23 is attached on a fixing table such as a chuck table and grinding the back surface 10B with a grinder or the like. The thickness of the wafer 10 after grinding is not particularly limited, but is usually 5 to 450 μm, preferably about 20 to 400 μm.

Next, the material of each member used in the present manufacturing method will be described in detail.
(Thermosetting resin layer)
The thermosetting resin layer 25 contains at least a thermosetting resin and can be adhered to the wafer 10, and when heated in a heat curing step described later, it becomes a protective film 25A.
Examples of the thermosetting resin used for the thermosetting resin layer 25 include epoxy resin, phenol resin, amino resin, unsaturated polyester resin, polyurethane resin, silicone resin, and thermosetting polyimide resin. The thermosetting resin can be used alone or in combination of two or more. As the thermosetting resin, an epoxy resin containing a small amount of ionic impurities and the like that corrode semiconductor elements is particularly preferable. Further, it is possible to contain a curing agent as the thermosetting resin, and for example, a phenol resin can be preferably used as the curing agent for the epoxy resin.
In the thermosetting resin layer 25, the thermosetting resin is preferably 5 to 70% by mass, more preferably 10 to 10% by mass, based on the total amount of the thermosetting resin layer (that is, the thermosetting resin composition). It is 50% by mass.

Further, the thermosetting resin layer 25 is preferably composed of a thermosetting resin composition containing a thermoplastic resin and a filler in addition to the thermosetting resin.
As the thermoplastic resin, acrylic resin, polyester resin, urethane resin, acrylic urethane resin, silicone resin, rubber polymer, phenoxy resin and the like can be used, but among these, acrylic resin is preferable.
The thermoplastic resin in the thermosetting resin layer is preferably 1 to 50% by mass, more preferably 5 to 40% by mass, based on the total amount of the thermosetting resin layer (that is, the thermosetting resin composition).

Further, as the filler, powders such as silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, and boron nitride, beads obtained by spheroidizing these, single crystal fibers, glass fibers, and the like are selected. Examples thereof include fillers, and among these, silica fillers or alumina fillers are preferable.
The filler in the thermosetting resin layer is preferably 5 to 75% by mass, more preferably 10 to 60% by mass, based on the total amount of the thermosetting resin layer (that is, the thermosetting resin composition).

In addition to the above components, the thermosetting resin composition may contain other additives such as a curing accelerator, a coupling agent, a pigment, and a colorant such as a dye.
The curing accelerator is not particularly limited, and for example, at least one selected from an amine-based curing accelerator, a phosphorus-based curing accelerator, an imidazole-based curing accelerator, a boron-based curing accelerator, a phosphorus-boron-based curing accelerator, and the like. Seeds can be used. Further, as the coupling agent, a silane coupling agent can be used.

(1st and 2nd base materials)
As the first base material 21, a resin film can be used, but one having heat resistance as described above is preferably used. The resin film constituting the first base material 21 may be a single-layer film made of one kind of resin film, or may be a multi-layer film in which a plurality of resin films are laminated.
Specific resin films include polyolefin films such as polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, ethylene-norbornene copolymer film, norbornene resin film; ethylene-vinyl acetate copolymer film. , Ethylene- (meth) acrylic acid copolymer film, ethylene- (meth) acrylic acid ester copolymer film and other ethylene-based copolymer films; polyvinyl chloride film, vinyl chloride copolymer film and other polyvinyl chloride Based film; polyester film such as polyethylene terephthalate film, polybutylene terephthalate film; polyurethane film, polyimide film, polyamide film, polyacetal film, polycarbonate film, polystyrene film, fluororesin film, modified polyphenylene oxide film , Polyphenylene sulfide film, polysulfone film and the like. Further, modified films such as these crosslinked films and ionomer films are also used.
Among these, as the resin film used for the first base material 21, polyester-based film, biaxially stretched polypropylene film, polyimide-based film, and polyamide-based film are preferable, polyester-based film is more preferable, and polyethylene terephthalate film is preferable. Is particularly preferable. Since these resin films have heat resistance and high rigidity, they prevent the thermosetting resin layer 23 from flowing in the step (II) and prevent the film thickness from becoming uneven.

Further, it is preferable to use a resin film as the second base material 31 used for the second support sheet 33. The second base material 33 can be appropriately selected from the above-mentioned resin films and used, but the second base material 31 does not need to have heat resistance and does not need to have high rigidity. The base materials used for the first and second base materials 31 and 33 may be the same or different from each other. Further, the first and second base materials 21 and 31 transmit energy rays when the pressure-sensitive adhesives constituting the first and second pressure-sensitive adhesive layers 22 and 23 are energy linear curable pressure-sensitive adhesives, respectively. Is preferable.
The thicknesses of the first and second substrates 21 and 31 are, for example, 10 to 300 μm, preferably 15 to 200 μm, respectively.

(1st and 2nd adhesive layers)
The adhesives forming the first and second adhesive layers 22 and 32 are not particularly limited, but are acrylic adhesives, rubber adhesives, silicone adhesives, polyester adhesives, urethane adhesives, and polyolefins. Examples thereof include based pressure-sensitive adhesives, vinyl alkyl ether-based pressure-sensitive adhesives, polyamide-based pressure-sensitive adhesives, fluorine-based pressure-sensitive adhesives, and styrene-diene block copolymer-based pressure-sensitive adhesives. Among these, acrylic-based pressure-sensitive adhesives are preferable. For example, when an acrylic pressure-sensitive adhesive is used for the first pressure-sensitive adhesive layer 22, the shear modulus of the pressure-sensitive adhesive layer is likely to be within the above range.
The pressure-sensitive adhesive is usually an acrylic resin, a rubber component, a silicone resin, a polyester resin, a urethane resin, a polyolefin resin, a vinyl alkyl ether resin, a polyamide resin, a fluorine resin, or a styrene-diene block copolymer. In addition to the adhesive components (main polymer) such as, if necessary, components such as a cross-linking agent, a pressure-sensitive agent, an antioxidant, a plastic agent, a filler, an antistatic agent, a photopolymerization initiator, and a flame retardant are contained. It consists of a pressure-sensitive adhesive composition. The adhesive component is a concept in which the polymer itself does not substantially have adhesiveness, but a plasticizing component, a polymer that develops adhesiveness by adding a pressure-sensitive adhesive, and the like are also widely included.

As described above, the first and second pressure-sensitive adhesive layers 22 and 32 may be formed from an energy ray-curable pressure-sensitive adhesive, or a non-energy ray-curable pressure-sensitive adhesive in which the pressure-sensitive adhesive does not cure even when irradiated with energy rays. It may be formed from an agent. The energy ray has an energy quantum in an electromagnetic wave or a charged particle beam, and refers to an active light such as an ultraviolet ray or an electron beam. However, in this production method, it is preferable to use an ultraviolet ray. Only one of the first and second pressure-sensitive adhesive layers 22 and 32 may be formed from the energy linear curable pressure-sensitive adhesive, or both may be formed from the energy linear curable pressure-sensitive adhesive.
Specifically, the energy ray-curable pressure-sensitive adhesive comprises an energy ray-curable pressure-sensitive adhesive containing a component having a photopolymerizable unsaturated group. The energy ray-curable pressure-sensitive adhesive is not particularly limited, but is a photopolymerizable unsaturated group such as a double bond on the main polymer (for example, acrylic polymer) of the pressure-sensitive adhesive itself (for example, on the side chain of the main polymer). Is introduced.
Further, as the energy ray-curable pressure-sensitive adhesive, an energy ray-polymerizable compound having a photopolymerizable unsaturated group may be blended in addition to the main polymer (for example, an acrylic polymer). In this case, the main polymer may or may not have a photopolymerizable unsaturated group introduced.

The first support sheet 23 preferably has heat resistance as described above, and therefore, the pressure-sensitive adhesive for forming the first pressure-sensitive adhesive layer 22 also preferably has heat resistance. As described above, the heat-resistant pressure-sensitive adhesive is not particularly limited as long as it can maintain a low adhesive strength even after heating, but specifically, the energy ray-curable acrylic pressure-sensitive adhesive (A). , Water-dispersible acrylic pressure-sensitive adhesive (B). Among these, the energy ray-curable acrylic pressure-sensitive adhesive (A) is preferable. The energy ray-curable acrylic pressure-sensitive adhesive (A) can easily exhibit heat resistance by irradiating it with energy rays and curing it before heating in the step (II).

An example of the energy ray-curable acrylic pressure-sensitive adhesive (A) is one containing an energy ray-curable acrylic polymer (A1) having a photopolymerizable unsaturated group in the side chain as a main component. The main component generally comprises 50% by mass or more of all the components of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, and preferably 70% by mass or more.
As the energy ray-curable acrylic polymer (A1), a (meth) acrylic acid ester-based copolymer in which active points such as _{-COOH, -NCO, epoxy group, -OH, and -NH 2 are introduced into the polymer chain (meth) acrylic acid ester-based polymer (meth).} Examples thereof include a compound obtained by reacting the active site of A2) with a compound having a photopolymerizable unsaturated group (hereinafter, also referred to as an unsaturated group-containing compound (X)).
In order to introduce the active point into the (meth) acrylic acid ester-based copolymer (A2), -COOH, -NCO, and epoxy are used when the (meth) acrylic acid ester-based copolymer (A2) is polymerized. A monomer having a functional group such as a group, -OH, or -NH _{2 may be used.}
In addition, in this specification, (meth) acrylic acid is used as a term indicating both "acrylic acid" and "methacrylic acid", and the same applies to other similar terms.

As the (meth) acrylic acid ester-based copolymer (A2), specifically, the co-weight of the (meth) acrylic acid alkyl ester having an alkyl group having 1 to 20 carbon atoms and another monomer. Coalescence is mentioned.
Examples of (meth) acrylic acid alkyl esters having an alkyl group having 1 to 20 carbon atoms include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, propyl (meth) acrylic acid, and butyl (meth) acrylic acid. , (Meta) pentyl acrylate, (meth) hexyl acrylate, (meth) cyclohexyl acrylate, (meth) 2-ethyl hexyl acrylate, (meth) isooctyl acrylate, (meth) decyl acrylate, (meth) acrylate Examples thereof include lauryl, myristyl (meth) acrylate, palmityl (meth) acrylate, and stearyl (meth) acrylate. These may be used alone or in combination of two or more.

Among these, it is preferable to use a (meth) acrylic acid alkyl ester having an alkyl group having 6 to 14 carbon atoms. Here, the (meth) acrylic acid alkyl ester having an alkyl group having 6 to 14 carbon atoms is 50 to 97% by mass with respect to the total amount of the monomers constituting the (meth) acrylic acid ester-based copolymer (A2). It is preferably 70 to 95% by mass, and more preferably 70 to 95% by mass. The (meth) acrylic acid alkyl ester having an alkyl group having 6 to 14 carbon atoms is preferably an alkyl group having 8 to 12 carbon atoms, specifically, 2-ethylhexyl (meth) acrylic acid. Lauryl acrylate is more preferred. As described above, by using the (meth) acrylic acid alkyl ester having an alkyl group having 6 to 14 carbon atoms, the heat resistance of the pressure-sensitive adhesive is likely to be improved, and the adhesive strength is unlikely to increase even when heated at a high temperature. Become.

Further, as the other monomer used in the (meth) acrylic acid ester-based copolymer (A2), the above-mentioned functional groups such as _{-COOH, -NCO, epoxy group, -OH, and -NH 2 are used.} Examples thereof include monomers having.
Here, examples of the monomer having a functional group include 2-hydroxyethyl (meth) acrylic acid, 2-hydroxypropyl (meth) acrylic acid, 3-hydroxypropyl (meth) acrylic acid, and (meth) acrylic acid. (Meta) Acrylic Acid Hydroxyalkyl Esters such as 2-Hydroxybutyl, (Meta) Acrylic Acid 3-Hydroxybutyl, (Meta) Acrylic Acid 4-Hydroxybutyl; (Meta) Acrylic Acid Monomethylaminoethyl, (Meta) Acrylic Acid Mono (Meta) Acrylic acid Monoalkylaminoalkyl such as ethylaminoethyl, (meth) acrylic acid monomethylaminopropyl, (meth) acrylic acid monoethylaminopropyl; acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, citracon Ethylene unsaturated carboxylic acid such as acid; isocyanate group-containing (meth) acrylic acid ester such as (meth) acryloyloxyethyl isocyanate; glycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, (3,4-epoxy) Examples thereof include epoxy group-containing (meth) acrylic acid esters such as cyclohexyl) methyl (meth) acrylate and 3-epoxycyclo-2-hydroxypropyl (meth) acrylate. Among these, hydroxyalkyl (meth) acrylate. It is preferable to use an ester.
The monomers having these functional groups may be used alone or in combination of two or more. Here, the monomer having a functional group is preferably 3 to 40% by mass, preferably 5 to 30% by mass, based on the total amount of the monomers constituting the (meth) acrylic acid ester-based copolymer (A2). Is more preferable.
Examples of other monomers include vinyl esters, olefins, halogenated olefins, styrene-based monomers, diene-based monomers, nitrile-based monomers, and N, N-dialkyl-substituted acrylamides. You may use it.

Examples of the unsaturated group-containing compound (X) that reacts with the active site include (meth) acryloyloxyethyl isocyanate, glycidyl (meth) acrylate, pentaerythritol mono (meth) acrylate, and dipentaerythritol mono (meth) acrylate. , Trimethylolpropane mono (meth) acrylate and other compounds having a photopolymerizable double bond can be appropriately selected and used according to the type of active site.

Further, the unsaturated group-containing compound (X) preferably reacts with a part of the functional group (active point) of the (meth) acrylic acid ester-based copolymer (A2), and specifically, (meth). It is preferable to react the unsaturated group-containing compound (X) with 50 to 90 mol% of the functional groups of the acrylic ester-based copolymer (A2), and more preferably 55 to 85 mol%.
As described above, in the energy ray-curable acrylic polymer (A1), a part of the functional group remains without reacting with the unsaturated group-containing compound (X), so that it is easily crosslinked by the cross-linking agent described later. .. As the functional group remaining without reaction _{, a functional group having -COOH, -OH, -NH 2} active hydrogen is preferable, and -OH is more preferable.

Further, the energy ray-curable acrylic pressure-sensitive adhesive (A) is not photopolymerizable in the side chain in addition to the energy ray-curable acrylic polymer (A1) having a photopolymerizable unsaturated group in the side chain. It may contain a non-energy ray-curable (meth) acrylic acid ester-based copolymer (A2) having no saturated group. In this case, as the (meth) acrylic acid ester-based copolymer (A2), the same one as described above can be used, but as described above, it has a functional group having an active hydrogen such as -OH. Is particularly preferred.

Further, as another example of the energy ray-curable acrylic pressure-sensitive adhesive (A), an energy ray-polymerizable compound containing an acrylic polymer as a main component and further selected from an energy ray-polymerizable oligomer and an energy ray-polymerizable monomer. Examples thereof include those containing (Y).
Here, as the acrylic copolymer, a (meth) acrylic acid ester-based copolymer (A2) having no photopolymerizable unsaturated group in the side chain described above is usually used. It is also possible to use an energy ray-curable acrylic polymer (A1) having a photopolymerizable unsaturated group in the side chain, or these (A2) and (A1) may be used in combination.

Examples of the energy ray-polymerizable oligomer include polyester acrylate-based, epoxy acrylate-based, urethane acrylate-based, polyol acrylate-based, and copolymerized oligomers which are copolymers of imide (meth) acrylate and ethylenically unsaturated group-containing monomers. And so on. Examples of the energy ray-polymerizable monomer include various monofunctional (meth) acrylates and polyfunctional (meth) acrylates. As specific examples of these energy ray-polymerizable oligomers and energy ray-polymerizable monomers, those described in Japanese Patent No. 4679896 can be used.
The amount of these energy ray-polymerizable oligomers and energy ray-polymerizable monomers used is selected so as to have the above-mentioned heat resistance by irradiation with energy rays.

The energy ray-curable acrylic pressure-sensitive adhesive preferably contains a cross-linking agent. By containing a cross-linking agent, the acrylic polymer can be easily cross-linked, so that the heat resistance can be easily improved. The cross-linking agent is not particularly limited, and any one can be appropriately selected and used from those conventionally used as a cross-linking agent in an acrylic pressure-sensitive adhesive. Examples of the cross-linking agent include polyisocyanate compounds, epoxy resins, melamine resins, urea resins, dialdehydes, methylol polymers, aziridine compounds, metal chelate compounds, metal alkoxides, metal salts and the like, but polyisocyanate compounds are preferable. Used.
Examples of polyisocyanate compounds include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanates, and alicyclic polyisocyanates such as hydrogenated diphenylmethane diisocyanate. , And their biuret, isocyanurate, and adduct, which is a reaction product with low molecular weight active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil. can.
One type of cross-linking agent may be used alone, or two or more types may be used in combination. The amount used depends on the type of the cross-linking agent, but is usually 0.01 to 20 parts by mass, preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the acrylic polymer in the pressure-sensitive adhesive. It is selected within the range of. The acrylic polymer is a non-energy ray-curable acrylic such as an energy ray-curable acrylic polymer (A1) contained in an adhesive and a (meth) acrylic acid ester-based copolymer (A2). It means both of the system polymers.

The energy ray-curable acrylic pressure-sensitive adhesive (A) preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include benzophenone-based, benzoin-based, acetophenone-based, thioxanthone-based, acylphosphine oxide-based, and titanocene-based photopolymerization initiators. These may be used alone or in combination of two or more, and the blending amount thereof is a component having a photopolymerizable unsaturated group in the pressure-sensitive adhesive (that is, an energy ray-polymerizable compound). (Y) and the total amount of the energy ray-curable acrylic polymer (A1)) 100 parts by mass, usually selected in the range of 0.2 to 20 parts by mass, preferably 0.5 to 10 parts by mass. be.
Further, the energy ray-curable acrylic pressure-sensitive adhesive includes various additives usually used for the acrylic pressure-sensitive adhesive, such as a pressure-sensitive adhesive, an antioxidant, and ultraviolet rays, as long as the object of the present invention is not impaired. Absorbents, light stabilizers, softeners, fillers and the like can be added.

The weight average molecular weight of the acrylic polymer used in the energy ray-curable acrylic pressure-sensitive adhesive is preferably 300,000 or more, preferably about 400,000 to 1,000,000. The weight average molecular weight is a standard polystyrene-equivalent value measured by the GPC method, and is specifically a method measured by an example described later.
In the energy ray-curable acrylic pressure-sensitive adhesive, the acrylic polymer may be contained in an amount capable of imparting tackiness to the pressure-sensitive adhesive, but is usually 50% by mass or more, preferably 75% by mass or more, based on the total amount of the pressure-sensitive adhesive. It is mass% or more.

The water-dispersible acrylic pressure-sensitive adhesive (B) contains a (meth) acrylic acid alkyl ester having an alkyl group having 4 to 12 carbon atoms as a main component and a carboxyl group-containing monomer. Examples thereof include those containing a copolymer emulsion obtained by emulsion polymerization of a monomer in the presence of an emulsifier. Here, as a specific example of the (meth) acrylic acid alkyl ester having an alkyl group having 4 to 12 carbon atoms, the above-mentioned (meth) acrylic acid alkyl ester is appropriately selected. The carboxyl group-containing monomer is appropriately selected from ethylenically unsaturated carboxylic acids.
Further, the copolymer emulsion may be an emulsion polymerization of a monomer further containing a monomer other than the (meth) acrylic acid alkyl ester and the carboxyl group-containing monomer, and as such a monomer. Is appropriately selected from various monomers that can be used for the (meth) acrylic acid ester-based copolymer (A2) described above.
When the water-dispersible acrylic pressure-sensitive adhesive (B) is also used, the pressure-sensitive adhesive preferably contains a cross-linking agent, and other additives may be added if necessary.

The thickness of the first pressure-sensitive adhesive layer 22 is appropriately adjusted according to the bump height, but is preferably 5 to 500 μm, more preferably 10 to 100 μm. The thickness of the second pressure-sensitive adhesive layer 32 is preferably 5 to 500 μm, more preferably 10 to 100 μm. The first and second pressure-sensitive adhesive layers 22 and 32 may be formed of the same material, but may be formed of different materials.
The first and second pressure-sensitive adhesive layers 22 and 32 are formed, for example, by diluting the above-mentioned pressure-sensitive adhesive with a diluent if necessary and then directly applying it to the first and second support sheets 23 and 33. , Apply to release material, heat and dry to form. When the pressure-sensitive adhesive layer is formed on the release material, the pressure-sensitive adhesive layer is further bonded to the first and second support sheets 23 and 33.

(Middle layer)
The intermediate layer used in the first and second support sheets 23 and 33 is preferably made by curing a curable material containing urethane (meth) acrylate. When the curable material contains urethane (meth) acrylate, it is possible to relieve the stress applied to the first and second support sheets 23 and 33. Therefore, in each step, it is possible to absorb vibrations and the like generated in the first and second support sheets 23 and 33.
The curable material may contain a monomer component such as an acrylic monomer in addition to urethane (meth) acrylate. As the acrylic monomer, an alicyclic compound such as isobornyl (meth) acrylate and dicyclopentenyl (meth) acrylate is preferable. The curable material is preferably cured by energy rays. When the curable material is cured by energy rays, it preferably contains a photopolymerization initiator.
When the first and second support sheets 23 and 33 both have an intermediate layer, the materials used for them may be the same, but may be different. The thickness of the intermediate layer is, for example, 5 to 1000 μm, preferably 10 to 500 μm.

According to the manufacturing method of the first embodiment described above, when the thermosetting resin layer 25 is heated and cured, as shown in FIG. 3, the first support is provided on the thermosetting resin layer 25. The sheets 23 are stacked. Therefore, when the thermosetting resin layer 25 is heated and cured, the fluidity of the thermosetting resin is suppressed by the first support sheet 23, and the film thickness of the protective film 25A is prevented from becoming non-uniform. Therefore, the protective film 25A, which is a cured product of the thermosetting resin layer 25, is laminated on the surface 10A of the semiconductor wafer 10 so as to embed the bump neck in a state having a uniform film thickness. It becomes possible to protect properly.
Further, due to the heating in the step (II), the adhesive force of the first support sheet 23 to the thermosetting resin layer 25 becomes heavy, and in the step (III), the first support sheet 23 cannot be peeled from the protective film 25A. However, as described above, such peeling failure can be prevented by using a first pressure-sensitive adhesive layer 22 having heat resistance.

<Second embodiment>
Next, the differences between the second embodiment of the present invention and the first embodiment will be described.
In the manufacturing process of the second embodiment, in addition to the steps (I) to (IV) described in the first embodiment, the steps (A-1), (A-2) and (A-3) are further described. Has.
(A-1) Step of attaching the second protective film forming layer to the back surface of the semiconductor wafer (A-2) Step of heating the second protective film forming layer to form the second protective film (A-3) Semiconductor A step of further adhering a second support sheet on the second protective film formed on the back surface of the wafer.

[Process (A-1)]
In this embodiment, as in the first embodiment, after performing steps (I) and (II) (that is, after thermosetting to form a protective film 25A on the surface 10A of the semiconductor wafer 10), As shown in FIG. 7, the second protective film forming layer 35 is attached to the back surface 10B (the surface opposite to the bump surface) of the semiconductor wafer. The second protective film forming layer 35 contains at least a thermosetting resin, and as will be described later, becomes a second protective film 35A when heated.
In this step, a film-like material made of the second protective film forming layer 35 may be attached to the back surface 10B of the semiconductor wafer 10, but for example, it is provided on one surface of a supporting base material (not shown). The obtained second protective film forming layer 35 may be attached to the back surface 10B of the semiconductor wafer 10. The supporting base material is removed by sticking the second protective film forming layer 35 on the back surface of the semiconductor wafer 10 and then peeling off from the second protective film forming layer 35. As the supporting base material, the same resin films as those of the first and second base materials 21 and 31 can be used.

Like the thermosetting resin layer 25, the second protective film forming layer 35 is preferably composed of a thermosetting resin composition containing a thermoplastic resin and a filler in addition to the thermosetting resin. Further, the thermosetting resin composition may further contain other additives such as a curing accelerator, a coupling agent, a pigment, a colorant such as a dye, and the like. The details of each material used for the second protective film forming layer 35, the blending amount, and the like are the same as those of the thermosetting resin layer 25 described in the first embodiment, and thus the description thereof will be omitted. The second protective film forming layer 35 may be formed of the same material as the thermosetting resin layer 25, but may be formed of a different material. The thickness of the second protective film forming layer 35 is, for example, 5 to 500 μm, preferably 10 to 100 μm.
After the step (A-1), the first support sheet 23 attached to the surface of the semiconductor wafer 10 is peeled off from the protective film 25A as in the first embodiment (step (III)).

[Process (A-2)]
Then, the second protective film forming layer 35 is heated and cured to form the second protective film 35A (step (A-2)). To heat the second protective film forming layer 35, a semiconductor wafer 10 in which the protective film 25A is formed on the front surface 10A side and the second protective film forming layer 35 is laminated on the back surface 10B side, for example, inside a heating furnace or the like. It is preferable to carry out by arranging and heating in. Since the heating conditions in this step (A-2) are the same as the heating conditions described in step (II), the description thereof will be omitted.

[Process (A-3)]
After the step (A-2), as shown in FIG. 8, the second support sheet 33 is attached to the back surface side of the semiconductor wafer 10, that is, on the second protective film 35A. The configuration of the second support sheet 33 is the same as that of the first embodiment. That is, FIG. 8 shows an embodiment in which the second support sheet 33 is attached to the second protective film 35A via the second pressure-sensitive adhesive layer 32, but the second pressure-sensitive adhesive layer is omitted and the first base material 31 May be directly adhered to the second protective film 35A, the first base material 31 is surface-treated, or a layer other than the pressure-sensitive adhesive layer is provided, and the second protective film is provided through the layer or the surface-treated surface. It may be affixed to 35A. Further, an intermediate layer may be further provided between the second pressure-sensitive adhesive layer 32 and the second base material 31.
[Process (IV)]
Next, as shown in FIG. 8, the semiconductor wafer 10 on which the protective film 25A and the second protective film 35A are formed is diced and separated into a plurality of semiconductor chips 15. In the step (IV) of the present embodiment, the protective film 25A and the second protective film 35B are also diced together with the semiconductor wafer 10 and divided according to the shape of the semiconductor chip 15. Since the details of the dicing step are the same as those of the first embodiment, the description thereof will be omitted.

After the dicing step, the semiconductor chip 15 is picked up and attached to the chip mounting substrate or the like by reflow, as in the first embodiment, and then, for example, the gap between the semiconductor chip 15 and the chip mounting substrate 40 is closed. A semiconductor device is manufactured by undergoing necessary steps such as sealing with a waterproof resin.

In the second embodiment as described above, similarly to the first embodiment, the thermosetting resin can be made difficult to flow, and the bump 11 can be appropriately protected by the protective film 25A. Further, the second protective film 35A can also protect the back surface of the semiconductor chip 15.
In the above second embodiment, laser printing may be performed on the second protective film 35A or the second protective film forming layer 35 formed on the back surface of the wafer. By performing laser printing, it is possible to display various marks, characters, and the like on the back surface side of the semiconductor chip 15.
In the above second embodiment, the cured second protective film 35A is exposed between the step (A-2) and the step (A-3). Therefore, it is preferable to perform laser printing on the exposed second protective film 35A between the steps (A-2) and the step (A-3). By printing on the cured second protective film 35A, the printability is improved as compared with the case of printing on the second protective film forming layer 35 before curing. Further, since the semiconductor wafer 10 is printed before being separated into individual pieces, batch printing is possible on a plurality of semiconductor chips. Further, by performing laser printing on the exposed second protective film 35A, efficient printing becomes possible. However, laser printing is performed by irradiating the second protective film 35A or the second protective film forming layer 35 that is not exposed (that is, covered with the second support sheet 33) with a laser via the second support sheet 33. May be done.

In the second embodiment, the steps (A-1), (A-2) and (A-3) are performed in this order, but instead, the steps (A-1) and (A) are performed. -3) and (A-2) may be performed in this order.
Specifically, steps (I), (II), (A-1) and (III) are carried out, a protective film 25A is formed on the surface 10A, and the second protective film forming layer 35 is formed on the back surface of the semiconductor wafer 10. It is attached to 10B, and then the first support sheet 23 is peeled off from the protective film 25A. Then, the second support sheet 33 is further bonded onto the second protective film forming layer 35 before curing, which is laminated on the back surface 10B (step (A-3)).
Then, after the second support sheet 33 is bonded, the second protective film forming layer 35 is cured by heating to form the second protective film 35A (step (A-2)), and thereafter, the semiconductor wafer 10 Is separated by dicing to manufacture a semiconductor device.
However, when (A-1), (A-3) and (A-2) are performed in this order, the second protective film 35A is formed on the second support sheet 33 until the dicing is completed after being formed by curing. It is covered and never exposed. Therefore, the laser printing performed on the cured second protective film 35A is performed by irradiating the laser through the second support sheet 33.

Further, when (A-1), (A-3) and (A-2) are carried out in this order, the second support sheet 33 is attached to the second protective film forming layer 35 in the step (A-2). In this state, heating will be performed. Therefore, when this is performed in this order, the second support sheet 33 preferably has heat resistance. That is, the second base material 31 of the second support sheet 33 is preferably a base material that does not melt or shrink significantly due to the heating in the step (A-2).
Further, the second support sheet 33 having heat resistance does not have high adhesiveness to the adherend even if it is heated for a predetermined time. Specifically, the second support sheet 33 having heat resistance preferably has an adhesive force of less than 10 N / 25 mm after heating in the step (A-2). Further, the adhesive strength is more preferably 0.3 to 9.8 N / 25 mm, further preferably 0.5 to 9.5 N / 25 mm. The method of measuring the adhesive strength of the second support sheet is the same as that of the first support sheet, but the adherend is the second protective film forming layer.
Since the second support sheet 33 has a relatively low adhesive force after heating in this way, when the semiconductor chip 15 is picked up from the second support sheet 33, peeling defects that the semiconductor chip 15 cannot pick up are less likely to occur.

The heat-resistant second support sheet 33 includes a second base material 31 and a second pressure-sensitive adhesive layer 32, and the second pressure-sensitive adhesive layer 32 is the above-mentioned first pressure-sensitive adhesive layer 31. Similarly, it is preferably formed from an energy ray-curable acrylic pressure-sensitive adhesive, a water-dispersion type acrylic pressure-sensitive adhesive, or the like. By using these adhesives, it is possible to provide a second support sheet 31 whose adhesive strength is difficult to improve even after heating. The first and second pressure-sensitive adhesive layers 22 and 32 may be formed of the same pressure-sensitive adhesive or different pressure-sensitive adhesives when they both have heat resistance.

Further, when the steps (A-1), (A-3) and (A-2) are carried out in this order, the heat curing (step (A-2)) does not need to be carried out before the dicing, and the dicing You may go later.
Specifically, in the same manner as above, steps (I), (II), (A-1) (III), and (A-3) are performed in this order, and then step (A-2) is performed. Dicing (process (IV)) is performed without. Therefore, dicing is performed on the semiconductor wafer 10 in which the cured protective film 25A is formed on the front surface 10A and the second protective film forming layer 35 before curing is laminated on the back surface 10B. Then, after dicing, the second protective film forming layer 35 is heated and cured (step (A-2)).
In this case, the heat curing of the second protective film forming layer 35 is preferably performed after picking up, and particularly preferably by heating at the time of reflow.
When the second protective film forming layer 35 is cured after being picked up, the semiconductor chip 15 (semiconductor wafer 10) is already peeled off from the second support sheet 33 during heating. Therefore, even if the second support sheet 33 does not have heat resistance as described above, the adhesive force of the support sheet 33 may become heavy due to the heating in the step (A-2), resulting in poor peeling. No. Further, when the second protective film forming layer 35 is cured by heating during reflow, it is not necessary to separately provide a step for curing the second protective film forming layer 35, so that the step can be simplified.

<Third embodiment>
Next, the differences between the third embodiment of the present invention and the second embodiment will be described.
In the second embodiment, the timing of heating and curing the thermosetting resin layer 25 and the second protective film forming layer 35 was different, but in the third embodiment, these are heated at the same time. And harden. That is, in the second embodiment, the step (II) and the step (A-2) are performed at different timings, whereas in the present embodiment, the step (II) and the step (A-2) are performed. Will be done all at once at the same timing.

Specifically, in the present embodiment, after the step (I) is performed (that is, after the first protective film forming film 20 is attached to the semiconductor wafer), the steps (II) and (III) are not performed. , Step (A-1) is performed, and the second protective film forming layer 35 is attached to the back surface 10B of the semiconductor wafer 10.
After that, as shown in FIG. 9, the thermosetting resin layer 25 and the second protective film forming layer 35 before curing are laminated on both sides, and the first support sheet 23 is laminated on the thermosetting resin layer 25. Further, by heating the semiconductor wafer 10, the thermosetting resin layer 25 and the second protective film forming layer 35 are cured to form the protective film 25A and the second protective film 35A (step (II) and step (step (II)). A-2)). The heating is performed by arranging, for example, the inside of the heating furnace a semiconductor wafer 10 in which the thermosetting resin layer 25 and the first support sheet 23 are laminated on the front surface and the second protective film forming layer 35 is laminated on the back surface. Since the heating method and heating conditions are the same as those in step (II) described in the first embodiment, the description thereof will be omitted.
Then, as in the second embodiment, the first support sheet 23 laminated on the protective film 25A is peeled off from the protective film 25A (step (III)).

Next, in the step (A-3), the second support sheet 33 is attached onto the second protective film 35A, and the dicing is subsequently performed in the step (IV). In the step (IV) of the present embodiment, the semiconductor wafer 10 having the cured protective film 25A and the second protective film 35A formed on both sides is diced. After dicing, the semiconductor device is manufactured in the present embodiment as well as in each of the above-described embodiments.

Also in the above third embodiment, as in the second embodiment, the bumps can be appropriately protected by the protective film 25A, and the back surface of the semiconductor chip 15 can also be protected by the second protective film 35A. Become. Further, in the present embodiment, since the thermosetting resin layer 25 and the second protective film forming layer 35 are simultaneously heated and cured, the process can be simplified.
Further, the thermosetting resin layer 25 and the second protective film forming layer 35 cause heat shrinkage when heat-cured, and the heat shrinkage may cause the semiconductor wafer 10 to warp. However, in the present embodiment, the thermosetting resin layer 25 and the second protective film forming layer 35 are heat-cured together to cancel out the force due to heat shrinkage generated at the time of curing. Therefore, in the present embodiment, the warpage of the wafer generated when the surface protective film resin layer 25 and the second protective film resin layer 35 are thermoset can be reduced.

<Fourth Embodiment>
Next, the differences between the first embodiment and the fourth embodiment of the present invention will be described.
The manufacturing process of the fourth embodiment further includes the following steps (B-1) and (B-2) in addition to the steps (I) to (IV) described in the first embodiment.
(B-1) A second protective film forming film including a second supporting sheet and a second protective film forming layer provided on the second supporting sheet is used as a bonding surface with the second protective film forming layer as a bonding surface. (B-2) A step of heating the second protective film forming layer to form the second protective film. That is, in the second to third embodiments, the second protective film is formed. Although the cambium and the second support sheet are separately attached to the back surface side of the semiconductor wafer, in the present embodiment, these are collectively formed as the second protective film forming film on the back surface side of the semiconductor wafer. It is affixed to.

[Process (B-1)]
In the present embodiment, similarly to the first embodiment, after performing steps (I) and (II) (that is, after thermosetting to form a protective film 25A on the semiconductor wafer 10), the semiconductor As shown in FIG. 11, the second protective film forming film 30 is attached to the back surface 10B (the surface opposite to the bump surface) of the wafer. As shown in FIG. 10, the second protective film forming film 30 includes a second supporting sheet 33 and a second protective film forming layer 35 provided on the second supporting sheet 33, and is provided with a second protective film forming layer 35. The protective film forming layer 35 is attached to the back surface 10B of the semiconductor wafer 10.
Here, as a specific example of the second support sheet 33, as shown in FIGS. 10 and 11, the second adhesive layer 32 formed on one surface of the second base material 31 and the second base material 31. A second protective film forming layer 35 is formed on the second adhesive layer 32, but as described in the first embodiment, the second protective film forming layer 35 has another structure. May be good.
As described in the first embodiment, the second support sheet 33 has a second protective film forming layer, for example, as shown in FIGS. 10 and 11 so that the outer peripheral region can be adhered to the support member 13 such as a ring frame. It is formed one size larger than 35.
Further, the second support sheet 33 may have the same size as the second protective film forming layer 35. When the second support sheet 33 has the same size as the second protective film forming layer 35, both the second protective film forming layer 35 and the second support sheet 33 are formed to be one size larger than the semiconductor wafer 10. An adhesive member such as a double-sided tape for adhering to the support member 13 may be provided on the outer peripheral region of the second protective film forming layer 35 that is not adhered to the semiconductor wafer 10.
After the above step (B-1), the first support sheet 23 attached to the surface of the semiconductor wafer 10 is peeled off from the protective film 25A in the same manner as in the first embodiment (step (III)).

[Process (B-2)]
Then, the second protective film forming layer 35 is heated and cured to form the second protective film 35A (step (B-2)). For heating the second protective film forming layer 35, for example, a semiconductor wafer 10 in which the protective film 25A is formed on the front surface 10A side and the second protective film forming layer 35 is laminated on the back surface 10B side is placed inside a heating furnace or the like. It is preferably carried out by arranging and heating. Since the heating conditions in this step (B-2) are the same as the heating conditions described in step (III) of the first embodiment, the description thereof will be omitted.

Next, the semiconductor wafer 10 having the protective film 25A and the second protective film 35A formed on both sides is diced (step (IV)). After dicing, the semiconductor chip 15 is picked up to manufacture a semiconductor device in the same manner as in each of the above embodiments.
In the present embodiment, when the second protective film forming layer 35 is heated and cured, the second support sheet 33 is attached to the second protective film forming layer 35. Therefore, it is preferable that the second support sheet 33 has heat resistance in order to prevent the adhesive force of the second support sheet 33 from becoming heavy during heating in the step (B-2). Since the second support sheet 33 having heat resistance is as described above, the description thereof will be omitted.

Also in the fourth embodiment described above, the bump 11 can be appropriately protected by the protective film 25A, and the back surface of the semiconductor wafer 10 (semiconductor chip 15) can be protected by the second protective film 35A. Further, in the present embodiment, the second protective film forming layer 35 and the second supporting sheet 33 are collectively attached to the back surface of the semiconductor wafer 10 as the second protective film forming film 30, thus simplifying the process. It is possible to do.

Further, in the description of the fourth embodiment, the example in which the step (B-2) is performed before the dicing (step (IV)) is shown, but the step (B-2) needs to be performed before the dicing. It may be done after dicing.
Specifically, steps (I), (II), (B-1), and (III) are performed in this order, and then dicing is performed (step (IV)). That is, in dicing, the semiconductor wafer 10 in which the protective film 25A is formed on the front surface 10A and the second protective film forming film 30 (that is, the second protective film forming layer 35 and the second support sheet 33) is laminated on the back surface 10B. To do. After the dicing, a step (B-2) of heating and curing the second protective film forming layer 35 is performed. In this case, the curing of the second protective film forming layer 35 is preferably performed after picking up, as in the second embodiment, and in particular, it is preferably cured by heating during reflow.

<Fifth Embodiment>
Next, the differences between the fifth embodiment of the present invention and the fourth embodiment will be described.
In the fourth embodiment, the timing of heating and curing the thermosetting resin layer 25 and the second protective film forming layer 35 was different, but in the fifth embodiment, they are heated at the same time. It cures. That is, in the fourth embodiment, the steps (II) and the steps (B-2) are performed at different timings, but in the present embodiment, the steps (II) and the steps (B-2) are collectively performed at the same timing. And do it.

That is, in the present embodiment, after the step (I) is carried out, the step (B-1) is carried out without performing the steps (II) and (III). In this way, in the present embodiment, as shown in FIG. 12, the surface 10A of the semiconductor wafer 10 has the first protective film forming film 20 (that is, the thermosetting resin layer 25 and the first support sheet 23). The second protective film forming film 30 (that is, the second protective film forming layer 35 and the second support sheet 33) are laminated on the back surface 10B.
Then, as shown in FIG. 12, the thermosetting resin is heated by heating the semiconductor wafer 10 in which the thermosetting resin layer 25 and the second protective film forming layer 35 before curing are laminated on both sides in this way. The layer 25 and the second protective film forming layer 35 are cured to form the protective film 25A and the second protective film 35A (steps (II) and (B-2)).

After heat curing, the first support sheet 23 attached to the protective film 25A is peeled off from the protective film 25A (step (III)). After that, the semiconductor wafer 10 supported by the second support sheet 33 is separated into pieces together with the protective film 25A and the second protective film 35A by dicing, and the protective film 25A and the second protective film 35A are formed on both sides of the semiconductor. Obtain chip 15 (step (IV)). Next, the semiconductor chip 15 is picked up, and the semiconductor device is manufactured in the same manner as in each of the above embodiments.
In the present embodiment, the second protective film forming layer 35 is heat-cured in a state where the second supporting sheet 33 is attached to the second protective film forming layer 35, so that the second supporting sheet 33 is added to the first supporting sheet. The 2 support sheet 33 also preferably has heat resistance. Since the structure of the second support sheet having heat resistance is as described above, the description thereof will be omitted.
Also in the fifth embodiment described above, it is possible to appropriately protect the bump 11 and the back surface of the wafer, simplify the process, and prevent warpage of the semiconductor wafer (semiconductor chip).

In each of the above embodiments, if the step (III) in which the first support sheet 23 is peeled off is performed between the steps (II) and the step (IV), the timing at which the first support sheet 23 is peeled off is not particularly limited. For example, in the second embodiment, it was performed between steps (A-1) and (A-2), but it may be performed before step (A-1) or at other timings. You may.
Also in the third embodiment, the step (III) was performed before the step (A-3), but after the step (A-3), that is, the step (A-3) and the step (IV). ) May be carried out.
Further, in the fourth embodiment, step (III) was performed between steps (B-1) and (B-2), but as long as it is performed between steps (II) and (IV). It may be performed before the step (B-1) or after the step (B-2).

Further, in the second to fifth embodiments, the back surface grinding of the semiconductor wafer is not particularly mentioned, but when the back surface grinding of the semiconductor wafer is performed, the step (I) is the same as in the first embodiment. It may be carried out between the step (I) and the step (III), but it is preferably carried out between the step (I) and the step (II). However, when the second protective film forming layer 35 is attached to the back surface 10B of the semiconductor wafer 10, the back surface grinding is performed before the second protective film forming layer 35 is attached.
Further, also in the third to fifth embodiments, laser printing may be performed on the second protective film 35A or the second protective film forming layer 35 as in the second embodiment. In the third embodiment, the cured second protective film 35A is exposed between the steps (II) and (A-2) and the step (A-3). Therefore, in the third embodiment, it is preferable to perform laser printing on the exposed second protective film 35A between the steps (II) and (A-2) and the step (A-3).

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

In this example and comparative example, various physical properties were measured by the following methods, and the film for forming the first protective film was evaluated.
[Weight average molecular weight (Mw) of acrylic polymer]
The weight average molecular weight (Mw) of the acrylic polymer was measured by the GPC method under the following measurement conditions and determined in terms of standard polystyrene.
To the high-speed GPC device "HLC-8120GPC" manufactured by Tosoh Corporation, the high-speed columns "TSKgradevolume H _XL- H", "TSKGel GMH _XL ", and "TSKGelG2000 H _XL " (all manufactured by Tosoh Corporation) are connected in this order. And measured. The column temperature was 40 ° C., the liquid feeding rate was 1.0 mL / min, and the detector was a differential refractometer.
[Adhesive strength measurement]
First, a laminate composed of a release material / thermosetting resin layer / release material is prepared, one of the release materials is peeled from the laminate, and the surface of the first support sheet on the side of the first pressure-sensitive adhesive layer is thermosetting. The resin layers were laminated at room temperature to obtain a laminate (first protective film forming film) composed of a first support sheet / thermosetting resin layer / release material. This laminated body was made into a strip shape having a width of 25 mm and a length of 150 mm.
As each of these members, the same members as those used in the examples were used.
Then, removing the release material from the strip-shaped laminate, the SUS304, the contact and the thermosetting resin layer surface and the SUS surface affixed at 70 ° C. using a rubber roller 2Kg, illuminance 200 mW / cm ^2, light quantity 160mJ The first support sheet was irradiated with ultraviolet rays under the condition of / cm ^2. Next, the adherend to which the first support sheet is attached is heated at 130 ° C. for 2 hours to cure the thermosetting resin layer to form a protective film, and then the adhesive force of the first support sheet to the protective film is measured. bottom. The adhesive strength was measured by peeling the first support sheet from the adherend at a peeling angle of 180 ° and a peeling speed of 300 mm / min under the conditions of a temperature of 23 ° C. and a humidity of 50% RH.
The adhesive strength is measured by irradiating the first support sheet with energy rays after the film for forming the first protective film is attached to the semiconductor wafer and before the thermosetting resin layer is heat-cured. It was done assuming.

[Example 1]
2-methacryloyloxyethyl isocyanate is derived from 2-hydroxyethyl acrylate in an acrylic ester-based copolymer which is a copolymer of 80 parts by mass of 2-ethylhexyl acrylate and 20 parts by mass of 2-hydroxyethyl acrylate. Photopolymerization is started on 100 parts by mass of an energy ray-curable acrylic polymer (weight average molecular weight (Mw): 600,000) obtained by adding so that the addition rate is 80 mol% based on 100 mol% hydroxyl group. Energy ray curing by blending 3 parts by mass of an agent (trade name: Esacure KIP150, manufactured by Siebel Hegner) and 0.5 parts by mass of a tolylene isocyanate-based cross-linking agent (trade name: BHS-8515, manufactured by Toyo Ink Co., Ltd.). The type acrylic pressure-sensitive adhesive was adjusted. The shear modulus of the energy ray-curable acrylic pressure-sensitive adhesive at 70 ° C. after irradiation with ultraviolet rays under the conditions described later was 40,000 Pa.
Next, a thickness obtained by energy ray-curing a curable material containing urethane (meth) acrylate on one surface of a base material (trade name: Cosmo Shine, manufactured by Toyobo Co., Ltd., thickness: 50 μm) made of a polyethylene terephthalate film. An intermediate layer of 200 μm was provided, and an energy ray-curable acrylic pressure-sensitive adhesive was applied on the intermediate layer so as to have a thickness of 10 μm to form a first pressure-sensitive adhesive layer to obtain a first support sheet. .. The first adhesive layer of the first support sheet was cured by irradiating it with ultraviolet rays under the conditions of an illuminance of 150 mW / cm ² and a light intensity of 300 mJ / cm ^2.

Further, an epoxy resin-based thermosetting resin composition was applied on the release material to form a thermosetting resin layer having a thickness of 100 μm on the release material. The melt viscosity of the thermosetting resin layer (epoxy resin-based thermosetting resin composition) at 70 ° C. was 5,000 Pa · S. The shear strength (against Cu) of the thermosetting resin layer after curing (that is, the protective film) was 200 N / 2 mm.
The thermosetting resin layer with the release material is laminated on the first pressure-sensitive adhesive layer of the first support sheet, and from the base material / intermediate layer / first pressure-sensitive adhesive layer / thermosetting resin layer / release material. The first protective film forming film was obtained.
After that, a semiconductor wafer (WALTS stock) provided with a pump (bump height: 210 μm) so that the thermosetting resin layer becomes a bonding surface at 70 ° C. on the first protective film forming film from which the release material has been peeled off. It was attached to the surface of a company-made product, size: 8 inches (20.32 cm), thickness: 730 μm (step (I)). Next, the semiconductor wafer to which the first protective film forming film was attached was heated at 130 ° C. for 2 hours to cure the thermosetting resin layer to form a protective film ((step (II)), and then protection. The first support sheet was peeled off from the film (step (III)).
When the protective film formed after the first support sheet was peeled off was observed, the film thickness of the protective film was uniform. Further, the tip of the bump protruded from the protective film, and the bump neck was appropriately embedded by the protective film. Therefore, in Example 1, by curing the thermosetting resin layer with the first support sheet attached, the bumps could be appropriately protected by the protective film having a uniform film thickness.

[Comparative Example 1]
It was carried out in the same manner as in Example 1 except that the step (III) and the step (II) were interchanged.
That is, in Comparative Example 1, after the first protective film forming film was attached to the surface of the semiconductor wafer (step (I)), the first support sheet was peeled off from the thermosetting resin layer (step (III)). ), Then, the semiconductor wafer on which the thermosetting resin layer was laminated on the surface was heated under the same heating conditions as in Example 1 to form a protective film (step (II)).
When the formed protective film was observed after the protective film was formed, it can be understood that in Comparative Example 1, the film thickness of the protective film became non-uniform and the bumps could not be properly protected.

[Example 2]
The adhesive strength of the first support sheet produced by the same method as in Example 1 was measured according to the above-mentioned adhesive strength measurement. The results are shown in Table 1.

[Example 3]
The same procedure as in Example 2 was carried out except that the blending amount of the cross-linking agent was changed to 1.5 parts by mass to prepare an energy ray-curable acrylic pressure-sensitive adhesive.

[Example 4]
The same procedure as in Example 2 was carried out except that the blending amount of the cross-linking agent was changed to 4.5 parts by mass to prepare an energy ray-curable acrylic pressure-sensitive adhesive.

[Example 5]
The same procedure as in Example 2 was carried out except that the blending amount of the cross-linking agent was changed to 7.5 parts by mass to prepare an energy ray-curable acrylic pressure-sensitive adhesive.

[Example 6]
The energy ray-curable acrylic polymer to be used is a 2-methacryloyloxyethyl isocyanate in an acrylic acid ester-based copolymer which is a copolymer of 80 parts by mass of lauryl acrylate and 20 parts by mass of 2-hydroxyethyl acrylate. Was added so that the addition rate was 80 mol% based on 100 mol% of hydroxyl groups derived from 2-hydroxyethyl acrylate (weight average molecular weight (Mw): 600, It was carried out in the same manner as in Example 2 except that it was changed to 000).

[Example 7]
The energy ray-curable acrylic pressure-sensitive adhesive to be used is added to an acrylic acid ester-based copolymer which is a copolymer of 90 parts by mass of 2-ethylhexyl acrylate and 10 parts by mass of 2-hydroxyethyl acrylate, and 2-methacryloyloxy. An energy ray-curable acrylic polymer obtained by adding ethyl isocyanate so that the addition rate is 60 mol% based on 100 mol% of hydroxyl groups derived from 2-hydroxyethyl acrylate (weight average molecular weight (Mw): 600,000) Similar to Example 2 except that the energy ray-curable acrylic pressure-sensitive adhesive obtained by blending 3 parts by mass of a photopolymerization initiator and 1 part by mass of a cross-linking agent with 100 parts by mass was changed. carried out.

[Reference example 1]
The energy ray-curable acrylic pressure-sensitive adhesive to be used is an acrylic acid ester-based copolymer which is a copolymer of 50 parts by mass of butyl acrylate, 20 parts by mass of methyl methacrylate, and 30 parts by mass of 2-hydroxyethyl acrylate. , 2-Methylloyloxyethyl isocyanate is added so that the addition rate is 90 mol% based on 100 mol% of hydroxyl groups derived from 2-hydroxyethyl acrylate (weight average). Molecular weight (Mw): 600,000) 100 parts by mass, changed to an energy ray-curable acrylic pressure-sensitive adhesive obtained by blending 3 parts by mass of a photopolymerization initiator and 1.0 part by mass of a cross-linking agent. Was carried out in the same manner as in Example 2.

In Examples 2 to 7 above, the pressure-sensitive adhesive used for the first support sheet is an energy ray-curable acrylic pressure-sensitive adhesive, and the (meth) acrylic acid ester-based copolymer (A2) is a specific monomer. By polymerizing from the above, it is possible to obtain heat resistance that does not increase the adhesive force even when the first support sheet is heated. Therefore, even if the semiconductor wafer is heated to cure the thermosetting resin layer while the first support sheet is attached to the thermosetting resin layer as in the present invention, the peelability of the first support sheet is good. It will be possible to maintain.
On the other hand, in Reference Example 1, when the first support sheet is heated, the adhesive strength is increased. Therefore, the semiconductor wafer is heated while the first support sheet is attached to the thermosetting resin layer to be thermally cured. When the sex resin layer is cured, the peelability of the first support sheet cannot be maintained well, and it is expected that the workability will be lower than that of Examples 2 to 7.

10 Semiconductor wafer 11 Bump 15 Semiconductor chip 20 First protective film forming film 21 First base material 22 First adhesive layer 23 First support sheet 25 Thermosetting resin layer 25A Protective film 30 Second protective film forming film 31 2nd base material 32 2nd adhesive layer 33 2nd support sheet 35 2nd protective film forming layer 35A 2nd protective film 40 Chip mounting substrate

Claims (11)

(I) A film for forming a first protective film in which a first support sheet and a thermosetting resin layer are provided in this order on the surface of a semiconductor wafer provided with bumps, and the thermosetting resin layer is bonded to the surface. The process of sticking them together as a surface
(II) A step of heating and curing the thermosetting resin layer to form a protective film, and
(III) A step of peeling the first support sheet from the protective film formed by curing the thermosetting resin layer.
(IV) A step of dicing the semiconductor wafer together with the protective film, and
A method for manufacturing a semiconductor device. (A-1) The process of bonding the second protective film forming layer to the back surface of the semiconductor wafer,
(A-2) The step of heating the second protective film forming layer to form the second protective film and (A-3) The second protective film forming layer or the second protection on the back surface of the semiconductor wafer. The method for manufacturing a semiconductor device according to claim 1, further comprising a step of laminating a second support sheet on the film. The method for manufacturing a semiconductor device according to claim 2 , wherein the curing of the second protective film forming layer in the step (A-2) is performed at the same time as the curing of the thermosetting resin layer in the step (II). (B-1) A second protective film forming film including a second supporting sheet and a second protective film forming layer provided on the second supporting sheet is attached to a surface to which the second protective film forming layer is bonded. Then, the process of bonding to the back surface of the semiconductor wafer and
(B-2) The method for manufacturing a semiconductor device according to claim 1, further comprising a step of heating the second protective film forming layer to form the second protective film. The method for manufacturing a semiconductor device according to claim 4 , wherein the curing of the second protective film forming layer in the step (B-2) is performed at the same time as the curing of the thermosetting resin layer in the step (II). The method for manufacturing a semiconductor device according to any one of claims 1 to 5, wherein the adhesive force after heating in the step (II) of the first support sheet is less than 10 N / 25 mm. The first support sheet includes a first base material and a first pressure-sensitive adhesive layer provided on one surface of the first base material, and the thermosetting resin layer is provided on the first pressure-sensitive adhesive layer. The method for manufacturing a semiconductor device according to any one of claims 1 to 6, wherein the method is provided. The method for manufacturing a semiconductor device according to claim 7, wherein the first support sheet comprises at least three layers of the first base material, an intermediate layer, and a first pressure-sensitive adhesive layer. The method for manufacturing a semiconductor device according to claim 8, wherein the intermediate layer contains urethane acrylate. ^{The melt viscosity of the thermosetting resin layer is 1 × 10 2} Pa · S or more ^{and less than 2 × 10 4} Pa · S at the temperature at which the first protective film forming film is attached to the semiconductor wafer.
^{The shear modulus of the first pressure-sensitive adhesive layer is 1 × 10 3} Pa or more and 2 × 10 ⁶ Pa or less at the temperature at which the first protective film forming film is attached to the semiconductor wafer according to claim 7. The method for manufacturing a semiconductor device according to the description. The method for manufacturing a semiconductor device according to any one of claims 1 to 10, wherein the thermosetting resin layer has a thickness of 0.01 to 0.99 times the bump height.

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