WO2022224900A1

WO2022224900A1 - Adhesive resin film and method for manufacturing electronic device

Info

Publication number: WO2022224900A1
Application number: PCT/JP2022/017801
Authority: WO
Inventors: 崇畦▲崎▼; 喬士甲斐; 貴信室伏; 仁木下
Original assignee: 三井化学東セロ株式会社
Priority date: 2021-04-20
Filing date: 2022-04-14
Publication date: 2022-10-27
Also published as: KR20230155529A; JPWO2022224900A1; TW202242053A; CN117178040A

Abstract

This adhesive resin film is provided with a base material layer, a concavo-convex absorptive resin layer, and an adhesive resin layer in this order, and is used to protect a circuit forming surface of an electronic component. The concavo-convex absorptive resin layer has a minimum value G'bmin of a storage elastic modulus G'b of 0.001 MPa or more and less than 0.1 MPa at 25°C or more and less than 250°C and has a storage elastic modulus G'b250 of 0.005 MPa to 0.3 MPa, inclusive, at 250°C.

Description

Adhesive resin film and method for manufacturing electronic device

The present invention relates to a method for manufacturing an adhesive resin film and an electronic device.

Electronic devices are usually manufactured by grinding the non-circuit-formed surface of the semiconductor wafer to reduce the thickness of the semiconductor wafer (back-grinding process), or forming electrodes on the non-circuit-formed surface of the semiconductor wafer after grinding by sputtering or the like. It is manufactured through a process (back metal process) and the like.
These steps are performed with a surface protection film attached to the circuit-formed surface of the semiconductor wafer in order to prevent contamination of the circuit-formed surface of the semiconductor wafer with grinding dust and grinding water.

The surface protective film used in this way is required to be able to follow the unevenness of the circuit formation surface of the semiconductor wafer well and to be able to be peeled off without leaving an adhesive residue.

As a semiconductor wafer surface protection film, for example, Patent Document 1 has a substrate layer A, an adhesive absorption layer B, and an adhesive surface layer C in this order. The minimum value G'bmin of the storage elastic modulus G'b of the adhesive absorbent layer B in the range of 25° C. or higher and lower than 250° C. is 0.001 MPa or higher and lower than 0.1 MPa. and the storage elastic modulus G′b250 at 250° C. is 0.005 MPa or more, and the temperature indicating the G′bmin is 50° C. or more and 150° C. or less, and the adhesive surface layer C has a temperature of 25° C. or more and 250° C. A semiconductor wafer surface protective film is disclosed in which the minimum value G'cmin of the storage elastic modulus G'c in the range of less than 0.03 MPa is 0.03 MPa or more.

Patent No. 6404475

In recent years, the thickness of electronic components has become thinner. According to the studies of the present inventors, as the thickness of electronic components becomes thinner, in the conventional semiconductor wafer surface protective film, after the surface protective film is attached to the non-circuit forming surface of the electronic component, the protective film is heat cured. It has been clarified that there is a tendency for the electronic component to warp during the grinding process and after the back grinding process. In particular, when the sealing resin and the semiconductor are integrated and the thickness of the sealing resin is relatively thick as in a wafer level chip size package (WLCSP), warping tends to occur easily. If the electronic component warps, it becomes difficult to handle the electronic component, or cracks occur in the electrodes.

The present invention has been made in view of the above circumstances, and provides an adhesive resin film capable of suppressing warping of electronic components (wafers, etc.) and a method of manufacturing an electronic device.

The present inventors have made extensive studies to solve the above problems. As a result, an adhesive resin film that includes a substrate layer, an unevenness-absorbing resin layer, and an adhesive resin layer in this order and is used to protect the circuit forming surface of an electronic component, The minimum value of the storage elastic modulus _{G'b in the range of 25 ° C. or higher and lower than 250 ° C. of the adhesive resin layer is in a specific range, and the storage elastic modulus G' b250} _at 250 ° C. is in a specific range. The inventors have found that warping of electronic parts can be suppressed by using such materials, and have completed the present invention.

That is, according to the present invention, the following adhesive resin film and a method for manufacturing an electronic device using the adhesive resin film are provided.

[1]
An adhesive resin film comprising a substrate layer, an uneven absorbing resin layer, and an adhesive resin layer in this order and used to protect the circuit forming surface of an electronic component,
The minimum value _G'bmin of the storage elastic modulus _G'b in the range of 25°C or higher and lower than 250°C of the uneven absorbent resin layer is 0.001 MPa or higher and lower than 0.1 MPa, and the storage elastic modulus _G'b at 250°C is 250. is 0.005 MPa or more and 0.3 MPa or less.
[2]
The adhesive resin film according to [1] above,
The adhesive resin film, wherein the loss tangent tan δ of the uneven absorbing resin layer at 250° C. is 0.05 or more and 1.2 or less.
[3]
The adhesive resin film according to [1] or [2] above,
The adhesive resin film, wherein the storage elastic modulus _G'b30 of the uneven absorbent resin layer at 30°C is 0.1 MPa or more.
[4]
The adhesive resin film according to any one of [1] to [3] above,
The adhesive resin film, wherein the irregularity absorbing resin layer is a layer containing a crosslinkable resin.
[5]
The adhesive resin film according to [4] above,
The adhesive resin film, wherein the crosslinkable resin contains at least one selected from the group consisting of ethylene/α-olefin copolymers and ethylene/vinyl ester copolymers.
[6]
The adhesive resin film according to [5] above,
The adhesive resin film, wherein the ethylene/vinyl ester copolymer contains an ethylene/vinyl acetate copolymer.
[7]
The adhesive resin film according to any one of [1] to [6] above,
Adhesive resin film that is a bag grind tape.
[8]
The adhesive resin film according to any one of [4] to [7] above,
The adhesive resin film, wherein the uneven absorbent resin layer further contains a cross-linking aid.
[9]
The adhesive resin film according to [8] above,
The cross-linking aid includes one or more selected from the group consisting of benzophenone compounds, divinyl aromatic compounds, cyanurate compounds, diallyl compounds, acrylate compounds, triallyl compounds, oxime compounds and maleimide compounds. the film.
[10]
The adhesive resin film according to any one of [1] to [9] above,
The adhesive resin film, wherein the resin constituting the base material layer contains one or more selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, and polyimide.
[11]
The adhesive resin film according to any one of [1] to [10] above,
The adhesive resin film, wherein the resin constituting the base material layer contains polyethylene naphthalate.
[12]
The adhesive resin film according to any one of [1] to [11] above,
The adhesive resin film, wherein the unevenness absorbing resin layer has a thickness of 10 μm or more and 1000 μm or less.
[13]
The adhesive resin film according to any one of [1] to [12] above,
The adhesive constituting the adhesive resin layer is one or more selected from (meth)acrylic adhesives, silicone adhesives, urethane adhesives, olefin adhesives and styrene adhesives. Adhesive resin film, including.
[14]
An electronic component having a circuit-forming surface, an adhesive laminated film attached to the circuit-forming surface of the electronic component, and a thermosetting adhesive attached to the surface of the electronic component opposite to the circuit-forming surface. a preparatory step (A) of preparing a structure comprising a protective film;
A thermosetting step (B) for thermosetting the thermosetting protective film by heating the structure;
A method of manufacturing an electronic device comprising
A method for producing an electronic device, wherein the adhesive laminated film is the adhesive resin film according to any one of [1] to [13] above.
[15]
A method for manufacturing an electronic device according to [14] above,
The above step (A) is
A curing step of thermally curing or ultraviolet curing the irregularity absorbing resin layer of the adhesive film in a state where the adhesive resin film is attached to the circuit forming surface of the electronic component;
a step of attaching the thermosetting protective film to the surface of the electronic component opposite to the circuit forming surface;
A method of manufacturing an electronic device comprising:
[16]
A method for manufacturing an electronic device according to [15] above,
A method for manufacturing an electronic device, wherein the heating temperature in the step of attaching the thermosetting protective film to the surface opposite to the circuit forming surface of the electronic component is 50° C. or higher and 90° C. or lower.
[17]
A method for manufacturing an electronic device according to [15] or [16] above,
In the step (A), before the curing step, the surface of the electronic component opposite to the circuit forming surface is adhered to the circuit forming surface of the electronic component. A method of manufacturing an electronic device, comprising a back-grinding step.
[18]
A method for manufacturing an electronic device according to any one of [14] to [17] above,
A method for manufacturing an electronic device, wherein the heating temperature in the step (B) is 120° C. or higher and 170° C. or lower.
[19]
A method for manufacturing an electronic device according to any one of [14] to [18] above,
A method of manufacturing an electronic device, wherein the circuit forming surface of the electronic component includes bump electrodes.
[20]
A method for manufacturing an electronic device according to [19],
A method of manufacturing an electronic device, wherein H/d is 0.01 or more and 1 or less, where H [μm] is the height of the bump electrode and d [μm] is the thickness of the uneven absorbing resin layer.

According to the present invention, it is possible to provide an adhesive resin film capable of suppressing warping of electronic components (wafers, etc.) and a method of manufacturing an electronic device.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which represented typically an example of the adhesive resin film which concerns on this embodiment. It is a sectional view showing typically an example of a manufacturing method of an electronic device of this embodiment. FIG. 2 is a diagram showing the relationship between temperature and storage elastic modulus G′ in Examples 1-3 and Comparative Examples 1-4. FIG. 2 is a graph showing the relationship between temperature and loss tangent tan δ in Examples 1-3 and Comparative Examples 1-4.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in all the drawings, the same constituent elements are given the same reference numerals, and the description thereof is omitted as appropriate. Also, the drawings are schematic diagrams and do not correspond to actual dimensional ratios. The numerical range "A to B" represents from A to B unless otherwise specified. In embodiments, "(meth)acrylic" means acrylic, methacrylic or both acrylic and methacrylic.

As described above, according to the studies of the present inventors, as the thickness of electronic parts becomes thinner, in the conventional semiconductor wafer surface protective film, after affixing the surface protective film to the circuit formation surface of the electronic parts, the above-mentioned protection It has been clarified that the electronic parts tend to warp when the film is thermally cured or after the back grinding process. In particular, when a resin and a semiconductor are integrated as in WLCSP and the thickness of the resin is relatively thick, warping tends to occur easily. If the electronic component warps, it becomes difficult to handle the electronic component, or cracks occur in the electrodes.

The present inventors have made extensive studies to solve the above problems. As a result, an adhesive resin film that includes a substrate layer, an unevenness-absorbing resin layer, and an adhesive resin layer in this order and is used to protect the circuit forming surface of an electronic component, The minimum value _G'bmin of the storage elastic modulus _G'b in the range of 25°C or higher and lower than 250°C of the elastic resin layer is 0.001 MPa or higher and lower than 0.1 MPa, and the storage elastic modulus _G'b250 at 250°C is 0.001 MPa or higher and lower than 0.1 MPa. It has become clear that it is possible to suppress warping of electronic components by using an adhesive resin film having a pressure of 005 MPa or more and 0.3 MPa or less.

FIG. 1 is a cross-sectional view schematically showing an example of the adhesive resin film according to this embodiment.
The adhesive resin film 50 (hereinafter also referred to as "adhesive laminated film 50") according to the present embodiment comprises a substrate layer 20, an irregularity absorbing resin layer 30, and an adhesive resin layer 40 in this order. Prepare. The adhesive resin film 50 is used to protect the circuit forming surface of the electronic component.

The storage elastic modulus of the uneven absorbent resin layer is measured under the following conditions.
・Measurement mode: dynamic viscoelasticity measurement mode ・Frequency: 6.28Hz
・Temperature increase rate: 3°C/min
・Temperature rise range: 0°C to 250°C
・How to prepare the viscoelastic sample:
{In the case of ethylene/vinyl acetate}
After the pellets are impregnated with additives, the pellets are melted on a parallel plate stage with a diameter of 25 mm heated to 100° C., then the stage gap is adjusted so that the thickness is about 500 μm, and a film is produced on the stage. . After that, the temperature can be lowered to 0° C. and held for 5 minutes before measurement can be performed.
{For acrylic intermediate layer}
In the case of acrylic interlayers, measurements can be made using the prepared layer.

The adhesive resin film 50 according to the present embodiment is used for protecting the surface of electronic components, fixing electronic components, forming electrodes, etc. in the manufacturing process of electronic devices. is used to protect the circuit formation surface of electronic parts (that is, the circuit surface containing the circuit pattern) in the process of grinding electronic parts (also called the back grinding process), which is one of the manufacturing processes of electronic devices. It can be suitably used in a process (back metal process) of forming electrodes by sputtering or the like on a grind tape or a non-circuit forming surface of a semiconductor wafer after grinding.

The adhesive resin film 50 according to the present embodiment is, for example, an adhesive film used for protecting and holding electronic components (for example, semiconductor wafers, sealing wafers, etc.) having surface irregularities in a dicing process, a transfer process, etc.; Adhesive film for temporarily fixing uneven electronic parts (e.g., semiconductor chips, semiconductor packages, etc.); dry polishing of electronic parts (e.g., semiconductor wafers, etc.); backside protection of electronic parts (e.g., semiconductor wafers, etc.) In the heating process of 90 ° C or higher such as pasting / curing of materials, formation of electromagnetic wave shielding film on electronic parts (e.g. semiconductor package etc.), metal film formation on the back surface of electronic parts (e.g. semiconductor wafer etc.) It can also be used as a film to be used.

<Base material layer>
The base material layer 20 is a layer provided for the purpose of improving properties such as handleability, mechanical properties, and heat resistance of the adhesive resin film 50 .
The base material layer 20 is not particularly limited, and examples thereof include resin films and metal foils.

Examples of the resin constituting the base material layer 20 include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefin resins; polyimide (PI); polyetheretherketone (PEEK); Polyvinyl chloride resin such as PVC); polyvinylidene chloride resin; polyamide resin; polyurethane; polystyrene resin; acrylic resin; can be mentioned.

Among these, the melting point of the resin constituting the base material layer 20 is preferably 250°C or higher, more preferably 265°C or higher, because it has high heat resistance. Melting points can be measured by differential scanning calorimetry (DSC). From the viewpoint of further improving heat resistance, the resin constituting such a base layer 20 preferably contains one or more selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, and polyimide. More preferably, it contains polyethylene naphthalate.

The base material layer 20 may be a single layer or two or more layers. The form of the resin film used to form the base material layer 20 may be a stretched film or a uniaxially or biaxially stretched film.

The thickness of the base material layer 20 is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 25 μm or more. By setting the thickness of the base material layer 20 to a certain value or more, it becomes easier to attach the adhesive resin film. In addition, it is easy to stably hold electronic parts (for example, semiconductor wafers) during grinding.
Also, the thickness of the base material layer 20 is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 100 μm or less. By setting the thickness of the base material layer 20 to a certain value or less, workability is facilitated when the adhesive resin film is peeled off.

The base material layer 20 may be subjected to surface treatment in order to improve adhesion with other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coat treatment, or the like may be performed.

<Uneven absorbent resin layer>
The adhesive resin film 50 according to this embodiment includes the uneven absorbent resin layer 30 between the base material layer 20 and the adhesive resin layer 40 .
The uneven absorbent resin layer 30 is a layer provided for the purpose of improving the followability of the adhesive resin film 50 to the circuit forming surface and improving the adhesion between the circuit forming surface and the adhesive resin film 50. is.
The minimum value _G'bmin of the storage elastic modulus _G'b of the uneven absorbent resin layer 30 in the range of 25°C or higher and lower than 250°C is 0.001 MPa or higher, preferably 0.002 MPa or higher, and more preferably 0.003 MPa or higher. be.
In addition, the _G′bmin of the uneven absorbent resin layer 30 in the range of 25° C. or more and less than 250° C. is less than 0.1 MPa, preferably less than 0.08 MPa, more preferably less than 0.05 MPa, and even more preferably less than 0.02 MPa. More preferably less than 0.01 MPa, more preferably less than 0.008 MPa, still more preferably less than 0.006 MPa, still more preferably less than 0.005 MPa.
When the G′ _bmin of the uneven absorbing resin layer 30 is within the range of 25° C. or more and less than 250° C., it is possible to improve the unevenness followability of the film and suppress the film from floating in a high-temperature process. . In addition, even if the electronic component is subjected to a high-temperature process such as a back metal process, it is possible to suppress cracking and adhesive residue of the electronic component during peeling.
In addition, the storage elastic modulus _G'b250 of the uneven absorbent resin layer 30 at 250° C. is 0.005 MPa or more and 0.3 MPa or less, preferably 0.007 MPa or more and 0.25 MPa or less, more preferably 0.01 MPa or more. It is 0.2 MPa or less, more preferably 0.02 MPa or more and 0.18 MPa or less, still more preferably 0.025 MPa or more and 0.18 MPa or less, and still more preferably 0.03 MPa or more and 0.17 MPa or less. When the storage elastic modulus G′ at 250° C. is within the above range, warping of the electronic component can be suppressed.

The loss tangent tan δ of the uneven absorbent resin layer 30 at 250° C. is preferably from 0.05 to 1.2, more preferably from 0.05 to 1.0, even more preferably from 0.06 to 0. 0.5 or less, more preferably 0.06 or more and 0.3 or less. If the loss tangent tan δ is within the above range, it is possible to suppress exudation of the uneven absorbent resin layer.

Further, the storage elastic modulus _G'b30 of the uneven absorbent resin layer 30 at 30°C is preferably 0.1 MPa or more, more preferably 0.15 MPa or more, still more preferably 0.3 MPa or more, further preferably 0.5 MPa or more, It is more preferably 0.8 MPa or more, and is, for example, 2 MPa or less, preferably 1.5 MPa or less, more preferably 1.3 MPa or less. If the storage elastic modulus G' _b30 at 30° C. is at least the above value, it is possible to further suppress warping of the electronic component and seepage of the uneven absorbent resin layer.

The material of the uneven absorbent resin layer 30 is not particularly limited, but may be, for example, one or more selected from polyolefin resins and polystyrene resins.

Among these, the uneven absorbent resin layer 30 is preferably a layer containing a crosslinkable resin having a melting point of 40°C or higher and 80°C or lower. The melting point of the crosslinkable resin can be measured with a differential scanning calorimeter (DSC).

By including a crosslinkable resin in the uneven absorbent resin layer 30, it can be effectively cured by heat or ultraviolet rays, and the heat resistance of the uneven absorbent resin layer 30 can be further improved. As a result, in the step of attaching the thermosetting protective film to the surface opposite to the circuit forming surface of the electronic component or the thermosetting step of thermosetting the thermosetting protective film, the uneven absorbent resin layer 30 is melted. It is possible to further suppress the protrusion of the resin.

The crosslinkable resin according to the present embodiment is not particularly limited as long as it can form the uneven absorbing resin layer 30 and is crosslinked by heat, ultraviolet rays, etc. to improve heat resistance. Ethylene/α-olefin copolymer containing 3 to 20 α-olefins, high density ethylene resin, low density ethylene resin, medium density ethylene resin, ultra-low density ethylene resin, linear low density polyethylene (LLDPE) resin, propylene (co)polymer, 1-butene (co)polymer, 4-methylpentene-1 (co)polymer, ethylene/cyclic olefin copolymer, ethylene/α-olefin/cyclic olefin Copolymer, ethylene/α-olefin/non-conjugated polyene copolymer, ethylene/α-olefin/conjugated polyene copolymer, ethylene/aromatic vinyl copolymer, ethylene/α-olefin/aromatic vinyl copolymer ethylene/carboxylic anhydride copolymers such as ethylene/unsaturated carboxylic anhydride copolymers, ethylene/α-olefin/unsaturated carboxylic anhydride copolymers; ethylene/epoxy-containing unsaturated compounds Ethylene/epoxy copolymers such as copolymers, ethylene/α-olefin/epoxy-containing unsaturated compound copolymers; ethylene/ethyl (meth)acrylate copolymers, ethylene/methyl (meth)acrylate copolymers coalescence, ethylene/propyl (meth)acrylate copolymer, ethylene/butyl (meth)acrylate copolymer, ethylene/hexyl (meth)acrylate copolymer, ethylene/2-hydroxyethyl (meth)acrylate Copolymers, ethylene/(meth)acrylic acid-2-hydroxypropyl copolymers, ethylene/(meth)acrylic acid ester copolymers such as ethylene/(meth)glycidyl (meth)acrylate copolymer; ethylene/(meth) ethylene-ethylenically unsaturated acid copolymers such as acrylic acid copolymers, ethylene-maleic acid copolymers, ethylene-fumaric acid copolymers, ethylene-crotonic acid copolymers; ethylene-vinyl acetate copolymers, Ethylene-vinyl ester copolymer such as ethylene-vinyl propionate copolymer, ethylene-vinyl butyrate copolymer, ethylene-vinyl stearate copolymer; ethylene-styrene copolymer, etc.; (meth)acrylic acid ester ( Unsaturated carboxylic acid ester (co)polymers such as co)polymers; ionomer resins such as ethylene/metal acrylate copolymers and ethylene/metal methacrylate copolymers Urethane-based resin; Silicone-based resin; Acrylic acid-based resin; Methacrylic acid-based resin; Cyclic olefin (co)polymer; α-olefin/aromatic vinyl compound/aromatic polyene copolymer; Aromatic vinyl compound; Aromatic polyene copolymer; Ethylene/aromatic vinyl compound/aromatic polyene copolymer; Styrene resin; Acrylonitrile/butadiene/styrene copolymer; Styrene/conjugated diene copolymer; Acrylonitrile/styrene Copolymer; acrylonitrile/ethylene/α-olefin/non-conjugated polyene/styrene copolymer; acrylonitrile/ethylene/α-olefin/conjugated polyene/styrene copolymer; methacrylic acid/styrene copolymer; ethylene terephthalate resin; Polyvinyl chloride; Polyvinylidene chloride; Polyolefin-based thermoplastic elastomer; Polystyrene-based thermoplastic elastomer; Polyurethane-based thermoplastic elastomer; 1,2-polybutadiene-based thermoplastic elastomer; One or two or more selected from chlorinated polyethylene thermoplastic elastomers; liquid crystalline polyesters; polylactic acid and the like can be used.

Among these, since cross-linking with a cross-linking agent such as an organic peroxide is easy, the cross-linkable resin according to the present embodiment includes ethylene and α-olefins having 3 to 20 carbon atoms. Copolymers, low density ethylene resins, medium density ethylene resins, ultra-low density ethylene resins, linear low density polyethylene (LLDPE) resins, ethylene/cyclic olefin copolymers, ethylene/α-olefin/cyclic Olefin Copolymer, Ethylene/α-Olefin/Non-Conjugated Polyene Copolymer, Ethylene/α-Olefin/Conjugated Polyene Copolymer, Ethylene/Aromatic Vinyl Copolymer, Ethylene/α-Olefin/Aromatic Vinyl Copolymer Olefin resin such as coalescence, ethylene/unsaturated carboxylic anhydride copolymer, ethylene/α-olefin/unsaturated carboxylic anhydride copolymer, ethylene/epoxy-containing unsaturated compound copolymer, ethylene/α-olefin/ Epoxy-containing unsaturated compound copolymer, ethylene-unsaturated carboxylic acid copolymer such as ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, 1,2-polybutadiene It is preferable to use one or more selected from thermoplastic elastomers.
Examples of the crosslinkable resin according to the present embodiment include ethylene/α-olefin copolymers composed of ethylene and α-olefins having 3 to 20 carbon atoms, low-density ethylene-based resins, ultra-low-density ethylene-based resins, linear low-density Density polyethylene (LLDPE) resin, ethylene/α-olefin/non-conjugated polyene copolymer, ethylene/α-olefin/conjugated polyene copolymer, ethylene/unsaturated carboxylic acid anhydride copolymer, ethylene/α-olefin/ Unsaturated carboxylic anhydride copolymer, ethylene/epoxy-containing unsaturated compound copolymer, ethylene/α-olefin/epoxy-containing unsaturated compound copolymer, ethylene/vinyl acetate copolymer, ethylene/acrylic acid copolymer , ethylene/unsaturated carboxylic acid copolymers such as ethylene/methacrylic acid copolymers, or two or more thereof are more preferably used.
Examples of the crosslinkable resin according to the present embodiment include ethylene/α-olefin copolymers composed of ethylene and α-olefins having 3 to 20 carbon atoms, low-density ethylene-based resins, ultra-low-density ethylene-based resins, linear low-density Density polyethylene (LLDPE) resin, ethylene/α-olefin/non-conjugated polyene copolymer, ethylene/α-olefin/conjugated polyene copolymer, ethylene/vinyl acetate copolymer, ethylene/acrylic acid copolymer, ethylene - It is more preferable to use one or more selected from the group consisting of ethylene/unsaturated carboxylic acid copolymers such as methacrylic acid copolymers.
Among these, the crosslinkable resin according to the present embodiment is more preferably at least one selected from the group consisting of ethylene/α-olefin copolymers and ethylene/vinyl ester copolymers. At least one selected from the group consisting of polymers and ethylene/vinyl acetate copolymers is more preferred, and ethylene/vinyl acetate copolymers are even more preferred. In addition, in this embodiment, the resins described above may be used alone, or may be used as a blend.

The α-olefin of the ethylene/α-olefin copolymer composed of ethylene and an α-olefin having 3 to 20 carbon atoms, which is used as the crosslinkable resin in the present embodiment, is usually an α-olefin having 3 to 20 carbon atoms. can be used singly or in combination of two or more. Among them, α-olefins having 10 or less carbon atoms are preferred, and α-olefins having 3 to 8 carbon atoms are particularly preferred. Examples of such α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, 4-methyl-1-pentene, , 1-octene, 1-decene, 1-dodecene and the like. Among these, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene are preferred because of their easy availability. The ethylene/α-olefin copolymer may be a random copolymer or a block copolymer, but a random copolymer is preferred from the viewpoint of flexibility.

Moreover, it is preferable that the uneven absorbent resin layer 30 further contains a cross-linking agent. By including a cross-linking agent in the uneven absorbent resin layer 30, the uneven absorbent resin layer 30 can be more effectively cured by heat or ultraviolet rays before the step (B) described later. It becomes possible to further improve the heat resistance of. As a result, in the step (A2) of attaching a thermosetting protective film to the surface opposite to the circuit forming surface of the electronic component described later and the thermosetting step (B) of thermosetting the thermosetting protective film 70, the electronic component can be further suppressed. Furthermore, in the step (A2) of attaching a thermosetting protective film to the surface opposite to the circuit forming surface of the electronic component and the thermosetting step (B) of thermosetting the thermosetting protective film, the uneven absorbent resin layer 30 It is possible to further suppress the occurrence of protrusion of the resin due to melting of the resin.
The cross-linking agent according to this embodiment is not particularly limited, but for example, an organic peroxide or a photo-crosslinking initiator can be used.
The content of the cross-linking agent in the uneven absorbent resin layer 30 is preferably 2.0 parts by mass or less, more preferably 1.0 parts by mass or less, relative to 100 parts by mass of the cross-linkable resin. It is more preferably 0.5 parts by mass or less.
The content of the cross-linking agent in the uneven absorbent resin layer 30 is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, with respect to 100 parts by mass of the cross-linkable resin. Preferably, it is more preferably 0.10 parts by mass or more.

Examples of organic peroxides include dilauroyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, dibenzoyl peroxide, cyclohexanone peroxide, di-t-butylperoxide, phthalate, cumene hydroperoxide, t-butyl hydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexene, 2,5-dimethyl-2,5-di(t-butylperoxy) oxy)hexane, t-amylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxymaleic acid, 1,1 -di(t-amylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di(t-amylperoxy)cyclohexane, t-amylperoxyisononanoate, t-amylperoxy normal octoate , 1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di(t-butylperoxy)cyclohexane, t-butylperoxy isopropyl carbonate, t-butylperoxy -2-ethylhexyl carbonate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-amyl peroxybenzoate, t-butyl peroxyacetate, t-butyl peroxyisononanoate, t-butyl Peroxybenzoate, 2,2-di(butylperoxy)butane, n-butyl-4,4-di(t-butylperoxy)butyrate, methyl ethyl ketone peroxide, ethyl-3,3-di(t-butyl peroxy)butyrate, dicumyl peroxide, t-butyl cumyl peroxide, t-butyl peroxybenzoate, di-t-butyl peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, acetylacetone peroxide 1 type or 2 or more types selected from etc. can be used.

Among these, 2,5-dimethyl-2,5-di(t-butylperoxy)hexene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, t-butylperoxy- It is preferable to use one or more selected from 2-ethylhexyl carbonate and t-butyl peroxybenzoate.

Examples of photocrosslinking initiators include benzophenone, benzophenone derivatives, thioxanthone, thioxanthone derivatives, benzoin, benzoin derivatives, α-hydroxyalkylphenones, α-aminoalkylphenols, acylphosphinooxides, and alkylphenylgluoxylates. , diethoxyacetophenone, oxime esters, titanocene compounds, and anthraquinone derivatives. Among them, benzophenone, benzophenone derivatives, benzoin, benzoin derivatives, α-hydroxyalkylphenones, oxime esters, and anthraquinone derivatives are preferred in terms of better crosslinkability, and benzophenone, benzophenone derivatives, and anthraquinone derivatives are more preferred. Benzophenone derivatives are more preferable because of their good transparency.
Preferred examples of benzophenone and benzophenone derivatives are benzophenone, 4-phenylbenzophenone, 4-phenoxybenzophenone, 4,4-bis(diethylamino)benzophenone, methyl o-benzoylbenzoate, 4-methylbenzophenone, 2,4,6-trimethyl Benzophenone and the like can be mentioned.
Preferred examples of anthraquinone derivatives include 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone and 1-chloroanthraquinone.

Moreover, from the viewpoint of further improving the heat resistance, it is preferable that the uneven absorbent resin layer 30 further contains a cross-linking aid.
As the cross-linking aid, for example, one or more selected from the group consisting of benzophenone compounds, divinyl aromatic compounds, cyanurate compounds, diallyl compounds, acrylate compounds, triallyl compounds, oxime compounds and maleimide compounds can be used. can.
The content of the cross-linking aid in the uneven absorbent resin layer 30 is preferably 5.0 parts by mass or less, more preferably 2.0 parts by mass or less with respect to 100 parts by mass of the cross-linkable resin. , more preferably 1.0 parts by mass or less, more preferably 0.5 parts by mass or less, and even more preferably 0.3 parts by mass or less.
The content of the cross-linking aid in the uneven absorbent resin layer 30 is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, relative to 100 parts by mass of the crosslinkable resin. It is more preferably 0.10 parts by mass or more, even more preferably 0.15 parts by mass or more.

Benzophenone compounds include, for example, 4-methylbenzophenone.
Examples of divinyl aromatic compounds include divinylbenzene and di-i-propenylbenzene.
Examples of cyanurate compounds include triallyl cyanurate and triallyl isocyanurate.
Examples of diallyl compounds include diallyl phthalate and the like.
The triallyl compound includes, for example, pentaerythritol triallyl ether.
Examples of acrylate compounds include diethylene glycol diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and tetramethylolmethane. tetra(meth)acrylate, tetramethylolmethane tetra(meth)acrylate and the like.
Examples of oxime compounds include p-quinonedioxime, pp'-dibenzoylquinonedioxime, and the like.
Examples of maleimide compounds include m-phenylenedimaleimide and the like.
Among these, the cross-linking aid is preferably a cyanurate compound, more preferably at least one selected from triallyl cyanurate and triallyl isocyanurate, and still more preferably triallyl isocyanurate.

The thickness of the uneven absorbing resin layer 30 is not particularly limited as long as it is a thickness capable of embedding the unevenness of the circuit forming surface of the electronic component. more preferably 30 μm or more and 800 μm or less, further preferably 50 μm or more and 700 μm or less, further preferably 100 μm or more and 700 μm or less, further preferably 300 μm or more and 600 μm or less , 400 μm or more and 600 μm or less.

When the height of the bump electrode present on the circuit forming surface of the electronic component is H [μm] and the thickness of the irregularity absorbing resin layer 30 is d [μm], H/d is preferably 1 or less, It is more preferably 0.85 or less, and even more preferably 0.7 or less. When H/d is equal to or less than the above upper limit value, it is possible to make the thickness of the adhesive resin film thinner and to improve the unevenness absorbability.
Although the lower limit of H/d is not particularly limited, it is, for example, 0.01 or more. The height of the bump electrode is generally 2 μm or more and 600 μm or less.

<Adhesive resin layer>
The adhesive resin layer 40 is a layer provided on one surface of the uneven absorbent resin layer 30, and is in contact with the circuit-forming surface of the electronic component when the adhesive resin film is attached to the circuit-forming surface of the electronic component. It is a layer that sticks together.

The adhesives constituting the adhesive resin layer 40 include (meth)acrylic adhesives, silicone adhesives, urethane adhesives, olefin adhesives, styrene adhesives, and the like. These can be used alone or in combination of two or more. Among these, a (meth)acrylic pressure-sensitive adhesive having a (meth)acrylic polymer as a base polymer is preferable because the adhesive force can be easily adjusted.

Moreover, as the adhesive that constitutes the adhesive resin layer 40, a radiation-crosslinking adhesive that reduces the adhesive force by radiation can also be used. Since the adhesive resin layer 40 made of the radiation-crosslinking adhesive is crosslinked by irradiation with radiation and the adhesive force is significantly reduced, in the step (C) of peeling the electronic component and the adhesive resin film, which will be described later, It becomes easy to separate the electronic component from the adhesive resin layer 40 . Radiation includes ultraviolet rays, electron beams, infrared rays, and the like.
As the radiation-crosslinkable pressure-sensitive adhesive, an ultraviolet-light-crosslinkable pressure-sensitive adhesive is preferable.

Examples of (meth)acrylic polymers contained in (meth)acrylic pressure-sensitive adhesives include homopolymers of (meth)acrylic acid ester compounds, copolymers of (meth)acrylic acid ester compounds and comonomers, and the like. mentioned. (Meth)acrylic acid ester compounds include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth) Acrylate, dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate and the like. These (meth)acrylic acid ester compounds may be used singly or in combination of two or more.
Examples of comonomers constituting the (meth)acrylic copolymer include vinyl acetate, (meth)acrylonitrile, styrene, (meth)acrylic acid, itaconic acid, (meth)acrylamide, methylol (meth)acryl amides, maleic anhydride, and the like. These comonomers may be used singly or in combination of two or more.

The radiation-crosslinkable adhesive contains, for example, the above (meth)acrylic polymer, a crosslinkable compound (a component having a carbon-carbon double bond), and a photopolymerization initiator or thermal polymerization initiator.

The crosslinkable compound includes, for example, a monomer, oligomer or polymer having a carbon-carbon double bond in the molecule and capable of being crosslinked by radical polymerization. Examples of such crosslinkable compounds include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neo Esters of (meth)acrylic acid and polyhydric alcohols such as pentyl glycol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate; ester (meth)acrylate oligomer; 2-propenyl di -isocyanurates or isocyanurate compounds such as 3-butenyl cyanurate, 2-hydroxyethylbis(2-(meth)acryloxyethyl)isocyanurate, tris(2-methacryloxyethyl)isocyanurate, methacryloyloxyethylisocyanate, etc. is mentioned.
When the (meth)acrylic polymer is a radiation-crosslinkable polymer having a carbon-carbon double bond in the side chain of the polymer, the crosslinkable compound may not be added.

The content of the crosslinkable compound is preferably 1 to 200 parts by mass, more preferably 2 to 100 parts by mass, and even more preferably 5 to 50 parts by mass with respect to 100 parts by mass of the (meth)acrylic polymer. When the content of the crosslinkable compound is within the above range, it becomes easier to adjust the adhesive force than when it is less than the above range, and the sensitivity to heat and light is too high compared to when it is more than the above range. It is difficult for deterioration of storage stability due to this to occur.

The photopolymerization initiator may be any compound that is cleaved to generate radicals upon exposure to radiation. Examples include benzoin alkyl ethers such as benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; , α-hydroxycyclohexylphenyl ketone; aromatic ketals such as benzyl dimethyl ketal; polyvinyl benzophenone;

Examples of thermal polymerization initiators include organic peroxide derivatives and azo polymerization initiators. Organic peroxide derivatives are preferred because they do not generate nitrogen when heated. Thermal polymerization initiators include, for example, ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxyesters and peroxydicarbonates.

A cross-linking agent may be added to the adhesive. Examples of cross-linking agents include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythrol polyglycidyl ether, and diglycerol polyglycidyl ether; tetramethylolmethane-tri-β-aziridinyl propionate; , trimethylolpropane-tri-β-aziridinylpropionate, N,N′-diphenylmethane-4,4′-bis(1-aziridinecarboxamide), N,N′-hexamethylene-1,6-bis Aziridine compounds such as (1-aziridine carboxamide); isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate and polyisocyanate; (Meth)acrylic acid such as (meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, etc. and esters with polyhydric alcohols.
The content of the cross-linking agent is 0.1 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the (meth)acrylic polymer from the viewpoint of improving the balance between the heat resistance and adhesion of the adhesive resin layer 40. is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 10 parts by mass or less, and 5 parts by mass or more and 10 parts by mass or less More preferred.

Although the thickness of the adhesive resin layer 40 is not particularly limited, it is preferably 1 μm or more and 100 μm or less, more preferably 3 μm or more and 50 μm or less, and even more preferably 5 μm or more and 20 μm or less.

The adhesive resin layer 40 can be formed, for example, by applying an adhesive coating liquid onto the uneven absorbent resin layer 30 .
As a method for applying the adhesive coating liquid, conventionally known coating methods such as roll coater method, reverse roll coater method, gravure roll method, bar coater method, comma coater method and die coater method can be employed. Although there are no particular restrictions on the drying conditions for the applied pressure-sensitive adhesive, it is generally preferred to dry in a temperature range of 80 to 200° C. for 10 seconds to 10 minutes. More preferably, it is dried at 80 to 170°C for 15 seconds to 5 minutes. In order to sufficiently accelerate the cross-linking reaction between the cross-linking agent and the pressure-sensitive adhesive, the pressure-sensitive adhesive coating liquid may be heated at 40 to 80° C. for about 5 to 300 hours after drying.

In the adhesive resin film according to the present embodiment, when the uneven absorbent resin layer 30 is cured with ultraviolet light or the adhesive resin layer 40 is crosslinked with ultraviolet light, the curing or crosslinking does not interfere with the object of the present invention. It is preferable to have a light transmittance to some extent.

The thickness of the entire adhesive resin film according to the present embodiment is preferably 25 μm or more and 1100 μm or less, more preferably 100 μm or more and 900 μm or less, still more preferably 200 μm or more and 800 μm or less, from the balance of mechanical properties and handleability. , more preferably 300 μm or more and 700 μm or less, further preferably 400 μm or more and 600 μm or less.

The adhesive resin film according to this embodiment may have an adhesive layer (not shown) between each layer. By providing the adhesive layer, the adhesion between each layer can be improved.

Next, an example of the method for manufacturing the adhesive laminated material according to this embodiment will be described.
First, the uneven absorbent resin layer 30 is formed on one surface of the substrate layer 20 by extrusion lamination. Next, an adhesive coating liquid is applied onto the uneven absorbent resin layer 30 and dried to form an adhesive resin layer 40, thereby obtaining an adhesive laminated film 50. FIG.
The substrate layer 20 and the uneven absorbent resin layer 30 may be formed by co-extrusion molding, or the film-like substrate layer 20 and the film-shaped uneven absorbent resin layer 30 may be laminated. may be formed by

Next, each step of the method for manufacturing the electronic device according to this embodiment will be described.
FIG. 2 is a cross-sectional view schematically showing an example of the method for manufacturing an electronic device according to this embodiment. The method for manufacturing an electronic device according to this embodiment includes the following steps (A) and (B).
(A) An electronic component 10 having a circuit-forming surface 10A, an adhesive laminated film 50 attached to the circuit-forming surface 10A of the electronic component 10, and a side opposite to the circuit-forming surface 10A of the electronic component 10 A preparation step of preparing a structure 60 comprising a thermosetting protective film 70 attached to the surface of
(B) A thermosetting step of thermosetting the thermosetting protective film 70 by heating the structure 60 .

(Step (A))
First, an electronic component 10 having a circuit forming surface 10A, an adhesive laminated film 50 attached to the circuit forming surface 10A side of the electronic component 10, and a surface 10C opposite to the circuit forming surface 10A of the electronic component 10 A structure 60 comprising a thermosetting protective film 70 attached thereto is prepared.

Such a structure 60 is produced, for example, by a step (A1) of attaching the adhesive laminated film 50 to the circuit forming surface 10A of the electronic component 10, and heating the surface 10C of the electronic component 10 opposite to the circuit forming surface 10A. It can be produced by performing the step (A2) of attaching the curable protective film 70 .

The method of attaching the adhesive laminated film 50 to the circuit forming surface 10A of the electronic component 10 is not particularly limited, and it can be attached by a generally known method. For example, it may be carried out manually, or may be carried out by a device called an automatic laminating machine to which the roll-shaped adhesive laminated film 50 is attached.

The method of attaching the thermosetting protective film 70 to the surface 10C of the electronic component 10 opposite to the circuit forming surface 10A is not particularly limited, and it can be attached by a generally known method. For example, it may be carried out manually, or may be carried out by a device called an automatic laminator to which a roll-shaped thermosetting protective film 70 is attached.

The step (A2) of attaching the thermosetting protective film 70 to the surface 10C of the electronic component 10 opposite to the circuit forming surface 10A is performed while heating the thermosetting protective film 70, for example. The heating temperature in the step (A2) is appropriately set depending on the type of the thermosetting protective film 70 and is not particularly limited.

The thermosetting protective film 70 is not particularly limited, and for example, a known thermosetting film for protecting the back surface of a semiconductor can be used.
The thermosetting protective film 70 includes, for example, a thermosetting adhesive layer, and may further include a protective layer as necessary.
The adhesive layer is preferably made of a thermosetting resin, and more preferably made of a thermosetting resin and a thermoplastic resin.
Examples of thermosetting resins include epoxy resins, phenol resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, and thermosetting polyimide resins. One or more of these thermosetting resins can be used. Among these, epoxy resins containing less ionic impurities and the like are preferred.
Examples of thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene/vinyl acetate copolymer, ethylene/acrylic acid copolymer, ethylene/acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, Examples include thermoplastic polyimide resins, polyamide resins, phenoxy resins, acrylic resins, saturated polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyamideimide resins, and fluorine resins. One or more of these thermoplastic resins can be used. Among these, acrylic resins having a low content of ionic impurities and the like are preferable.

The adhesive layer can contain other additives as needed. Other additives include, for example, fillers, flame retardants, silane coupling agents, ion trapping agents, extenders, antioxidants, antioxidants, surfactants and the like.

The protective layer is made of, for example, heat-resistant resin, metal, or the like.
The heat-resistant resin constituting the protective layer is not particularly limited, but examples include polyphenylene sulfide, polyimide, polyetherimide, polyarylate, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, liquid crystal polymer, and polytetrafluoro. ethylene and the like. Among these, polyimide, polyphenylene sulfide, polysulfone, polyetherimide, polyetherketone, polyetheretherketone and the like can be mentioned.
The metal forming the protective layer is not particularly limited, and examples thereof include aluminum, alumite, stainless steel, iron, titanium, tin, and copper.

A commercially available film may be used as the thermosetting protective film 70 . Commercially available films include, for example, Lintec's chip back surface protective tape (product name: "LC tape" series).

The electronic component 10 is not particularly limited as long as it has a circuit forming surface 10A. Examples thereof include a semiconductor wafer, a sapphire substrate, a lithium tantalate substrate, a mold wafer, a mold panel, a mold array package, and a semiconductor substrate. be done.
Examples of semiconductor substrates include silicon substrates, germanium substrates, germanium-arsenic substrates, gallium-phosphorus substrates, gallium-arsenic-aluminum substrates, and gallium-arsenic substrates.

In addition, the electronic component 10 may be an electronic component for any purpose, but for example, an electronic component for logic (for example, for communication, for high-frequency signal processing, etc.), for memory, for sensor, for power supply, etc. mentioned. These may be used alone or in combination of two or more.

10 A of circuit formation surfaces of the electronic component 10 have an uneven structure by having the electrode 10B, for example.
Further, when the electronic device is mounted on the mounting surface, the electrode 10B is joined to the electrode formed on the mounting surface to provide an electrical connection between the electronic device and the mounting surface (mounting surface such as a printed circuit board). It forms a connection.
Examples of the electrodes 10B include bump electrodes such as ball bumps, printed bumps, stud bumps, plated bumps, and pillar bumps. That is, the electrode 10B is normally a convex electrode. These bump electrodes may be used singly or in combination of two or more.
Also, the type of metal forming the bump electrode is not particularly limited, and examples thereof include silver, gold, copper, tin, lead, bismuth, and alloys thereof. These metal species may be used singly or in combination of two or more.

In the method for manufacturing an electronic device according to the present embodiment, the uneven absorbent resin layer 30 in the adhesive laminated film 50 is thermally cured or It is preferable to perform the curing step (A3) of ultraviolet curing. Thereby, the heat resistance of the adhesive laminated film 50 can be improved. By doing so, the step (A2) of attaching the thermosetting protective film 70 to the surface 10C opposite to the circuit forming surface 10A of the electronic component 10 and the thermosetting step (B ), warping of the electronic component 10 can be suppressed. Furthermore, in the step (A2) of attaching the thermosetting protective film 70 to the surface 10C opposite to the circuit forming surface 10A of the electronic component 10 and the thermosetting step (B) of thermosetting the thermosetting protective film 70, the unevenness It is possible to prevent the absorbent resin layer 30 from being melted and causing the resin to stick out. Although the curing step (A3) is not particularly limited, it is preferably performed before the step (A2) of attaching the thermosetting protective film 70 to the surface 10C of the electronic component 10 opposite to the circuit forming surface 10A.

The method for thermosetting the uneven absorbent resin layer 30 is not particularly limited, but for example, thermal crosslinking using a radical polymerization initiator can be mentioned. A known thermal radical polymerization initiator can be used for thermal crosslinking with a radical polymerization initiator.

Further, by irradiating the uneven absorbing resin layer 30 with ultraviolet rays, the uneven absorbing resin layer 30 can be crosslinked and cured. For example, ultraviolet rays are applied from the surface of the adhesive laminated film on the side of the base layer 20 .
Also, in any of the crosslinking methods, the uneven absorbent resin layer 30 may be crosslinked by blending a crosslinking aid with the uneven absorbent resin layer 30 .

In the method for manufacturing an electronic device according to the present embodiment, in a state where the adhesive laminated film 50 is attached to the circuit forming surface 10A of the electronic component 10, the surface 10C opposite to the circuit forming surface 10A of the electronic component 10 is A back grinding step (A4) for back grinding may be performed. That is, the adhesive laminated film 50 according to this embodiment may be used as a back grind tape. Here, if the curing step (A3) is performed before the back grinding step (A4), the adhesive strength of the adhesive laminated film 50 is reduced, so that the adhesive laminated film 50 is peeled off in the back grinding step (A4). There is a concern that Therefore, it is preferable to perform the back grinding step (A4) before the curing step (A3).

In the back grinding step (A4), the surface 10C of the electronic component 10 attached to the adhesive laminated film 50 opposite to the circuit forming surface 10A is back ground.
Here, back grinding means thinning to a predetermined thickness without breaking or damaging the electronic component 10 .
Back grinding of the electronic component 10 can be performed by a known method. For example, there is a method of fixing the electronic component 10 to a chuck table or the like of a grinder and grinding the surface 10C of the electronic component 10 opposite to the circuit forming surface 10A.

Although the back surface grinding method is not particularly limited, for example, a known grinding method such as a through-feed method or an in-feed method can be adopted. Grinding can be performed while cooling the electronic component 10 and the whetstone with water.

(Step (B))
Next, the structure 60 is heated to thermally cure the thermosetting protective film 70 .

The heating temperature in the step (B) of thermosetting the thermosetting protective film 70 is not particularly limited because it is appropriately set depending on the type of the thermosetting protective film 70, but is, for example, 120° C. or higher and 170° C. or lower, preferably It is 130°C or higher and 160°C or lower.

(Step (C))
Further, in the method for manufacturing an electronic device according to the present embodiment, a step (C) of peeling the electronic component 10 and the adhesive laminated film 50 may be further performed after the step (B). By performing this step (C), the electronic component 10 can be peeled off from the adhesive laminated film 50 .
The peeling temperature is, for example, 20 to 100.degree.
The peeling of the electronic component 10 and the adhesive laminated film 50 can be performed by a known method.

(Other processes)
The method for manufacturing an electronic device according to this embodiment may have other processes than those described above. As other steps, known steps in the method of manufacturing an electronic device can be used.

For example, metal film forming process, annealing process, dicing process, die bonding process, wire bonding process, flip chip bonding process, cure heating test process, sealing process, reflow process, etc. are generally performed in electronic component manufacturing processes. Any steps described above may be further performed.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than those described above can also be adopted.

It should be noted that the present invention is not limited to the above-described embodiments, and includes modifications, improvements, etc. within the scope of achieving the object of the present invention.

The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these.

<Base material layer>
Base layer: polyethylene naphthalate film (product name: Teonex Q81, manufactured by Toyobo Film Solution Co., Ltd., thickness: 50 μm, described as “PENQ81” in Table 1)

<Resin for forming uneven absorbent resin layer>
Resin 1: Ethylene/vinyl acetate copolymer (product name: Evaflex EV150, manufactured by Mitsui Dow Polychemicals, melting point: 61°C)
Resin 2: Polymer P1
Synthesis of (meth)acrylic acid ester polymer P1 having a thermally polymerizable double bond 48 parts by mass of ethyl acrylate, 27 parts by mass of 2-ethylhexyl acrylate, 20 parts by mass of methyl acrylate, 5 parts by mass of glycidyl methacrylate and initiation of polymerization As an agent, 0.2 parts by mass of benzoyl peroxide (converted to solid content) was mixed. The resulting solution was added dropwise to a nitrogen-substituted flask containing 65 parts by mass of toluene and 50 parts by mass of ethyl acetate with stirring at 80° C. over 5 hours, and the mixture was further stirred for 5 hours to react. After completion of the reaction, the resulting solution was cooled, 25 parts by mass of xylene, 2.5 parts by mass of acrylic acid, and 1.5 parts by mass of tetradecylbenzylammonium chloride were added and reacted at 80°C for 10 hours while blowing air. to obtain a solution of a (meth)acrylate polymer P1 having a thermally polymerizable double bond. The content of structural units derived from glycidyl methacrylate was 3.926 mol % with respect to all structural units constituting polymer P1.

<Resin for Forming Adhesive Resin Layer>
As a resin for forming an adhesive resin layer, the following adhesive coating solution was used.
Adhesive polymer n-butyl acrylate 77 parts by mass, methyl methacrylate 16 parts by mass, 2-hydroxyethyl acrylate 16 parts by mass, and 0.3 t-butyl peroxy-2-ethylhexanoate as a polymerization initiator 20 parts by mass of toluene and 80 parts by mass of ethyl acetate were reacted for 10 hours. After completion of the reaction, the solution was cooled, and 30 parts by mass of toluene, 7 parts by mass of methacryloyloxyethyl isocyanate (manufactured by Showa Denko K.K., product name: Karenz MOI), and 0.05 parts by mass of dibutyltin dilaurate were added. In addition, the mixture was allowed to react at 85° C. for 12 hours while blowing in air to obtain an adhesive polymer solution.
・ Adhesive coating liquid For 100 parts by mass of the above adhesive polymer (solid content), 8 parts by mass of benzyl dimethyl ketal (manufactured by BAFS, product name: Dolphin Guar 651) as a photoinitiator, an isocyanate cross-linking agent (Mitsui Chemicals Company, trade name: Orester P49-75S) 2.33 parts by mass, ditrimethylolpropane tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: AD-TMP) 6 parts by mass are added to prepare an adhesive coating solution. Obtained.

(Example 1)
To Resin 1 (100 parts by mass), 0.22 parts by mass of triallyl isocyanurate (manufactured by Mitsubishi Chemical Corporation, trade name: TAIC) as a cross-linking agent and t-butylperoxy-2-ethylhexyl carbonate (t-butylperoxy-2-ethylhexyl carbonate) as a cross-linking agent ( A composition was obtained by dry-blending 0.16 parts by mass of Luperox TBEC (trade name, manufactured by Arkema Yoshitomi Co., Ltd.). Next, the composition obtained by melt-kneading with Labo Plastomill was molded with a hot press to a thickness of 500 μm to obtain an uneven absorbent resin layer.
Then, the substrate layer was attached to the uneven absorbent resin layer to obtain a laminated film.

Next, the adhesive coating liquid for the adhesive resin layer was applied to a polyethylene terephthalate film that had been subjected to silicone release treatment, and dried to form an adhesive resin layer with a thickness of 10 μm. Then, an adhesive resin film was obtained by laminating the obtained adhesive resin layer to the uneven absorbent resin layer side of the laminated film. The obtained adhesive resin film was evaluated as follows. Table 1 shows the results obtained.

<Evaluation>
(1) Evaluation of storage elastic modulus G′ and loss tangent tan δ The storage elastic modulus was measured using a dynamic viscosity measuring device (TA Instruments viscoelasticity measuring device ARES, using a parallel plate with a diameter of 25 mm) at a frequency of 6.5 mm. Measurements were made at 28 Hz over a temperature range of 0°C to 250°C. Specifically, the sample is set in the dynamic viscoelasticity measuring device via the parallel plate jig at 100° C., and the storage modulus is measured while increasing the temperature from 0° C. to 250° C. at a rate of 3° C./min. It was measured.
After the end of the measurement, in the storage modulus-temperature curve obtained from 0°C to 250°C, the temperature at which the storage modulus becomes minimum in the range of 25°C or more and less than 250°C and its value ( _G'min ), 30 The storage elastic modulus G'30 at °C and the storage elastic modulus _G'250 at ₂₅₀ °C were read. In addition, loss tangent tan δ was also measured. FIG. 3 shows the relationship between storage modulus and temperature. FIG. 4 shows the relationship between loss tangent and temperature.

(2) Evaluation of Warpage of Silicon Test Piece A test piece was prepared by dividing a silicon wafer ground to a thickness of 75 μm into pieces of 5 cm×2.5 cm. Peel off the silicone release treated polyethylene terephthalate film on the adhesive resin layer side of the adhesive resin film, and attach the adhesive resin layer side of the adhesive resin film to the test piece on a hot plate heated to 70 ° C. , the adhesive film was cut along the size of the test piece to prepare an adhesive resin film/silicon test piece laminate. After that, the laminate was placed on the release surface of a polyethylene terephthalate film treated with silicone release treatment with the silicon test piece side down, and placed in a heating oven, where it was heated at 150° C. for 2 hours and 30 minutes. After that, the removed laminate was left to stand and cooled for 10 minutes, and then the silicon test piece side of the laminate sample was turned down, and the center part of one short side (2.5 cm width) of the laminate sample was touched from above with a finger. The height of the middle point of the other short side of the sample lifted up at that time from the bottom was measured with a ruler, and the value was taken as the warpage.
The values of warpage (unit: mm) are shown in the table.

(3) Warp of 8-inch Silicon Wafer An 8-inch (200 mm) silicon wafer with a thickness of 100 μm was attached to an adhesive resin film. After that, it was placed in a heating oven and heated at 150° C. for 2 hours. After that, the laminated body taken out was allowed to stand and cooled for 10 minutes, and then the warpage of the silicon wafer was measured with a ruler. In the table, "-" means no evaluation, and "x" means the result of large warp.

(4) Evaluation of Exudation of Uneven Absorbent Resin Layer It was visually confirmed whether the uneven absorbent resin layer exuded from the end of the test piece after the warp evaluation. In addition, when it was exuded, it was confirmed whether the exuded resin layer was stuck to the polyethylene terephthalate film.
The bleeding was evaluated according to the following criteria.
◎: No exudation ○: There is exudation, but it does not stick to the polyethylene terephthalate film treated with silicone release treatment ×: There is exudation, but it sticks to the polyethylene terephthalate film treated with silicone release treatment

(5) Evaluation of Appearance Appearance was evaluated based on the following criteria.
◎: No air bubbles ○: There are air bubbles, but the total area of the air bubbles is less than 30% of the total area of the test piece ×: There are air bubbles, and the total area of the air bubbles is 30% or more of the total area of the test piece

(Examples 2-3)
Adhesive resin films were produced in the same manner as in Example 1, except that the type of the uneven absorbent resin layer was changed to those shown in Table 1. Moreover, each evaluation was performed similarly to Example 1, respectively. The obtained results are shown in Table 1, respectively.

(Comparative Examples 1 to 4)
Adhesive resin films were produced by changing the uneven absorbent resin layer to those shown in Table 1. Moreover, evaluation was performed in the same manner as in Example 1. Table 1 shows the results obtained. Olestar P49-75S in Table 1 is an isocyanate cross-linking agent (manufactured by Mitsui Chemicals, trade name: Olestar P49-75S), and Percadox 12 is an organic peroxide (manufactured by Kayaku Nourion Co., Ltd., trade name Name: Parkadox 12).

In Comparative Examples 1 and 2, warpage of the test piece and warpage of the silicon wafer could not be suppressed. In Comparative Examples 3 and 4, warpage of the test piece could be suppressed, but warpage of the silicon wafer could not be suppressed. Also, in Comparative Examples 3 and 4, the tan δ value at 250° C. was too high, so exudation occurred during heating.
On the other hand, in Examples 1 and 2, warping of the test piece and the silicon wafer could be suppressed. In addition, exudation of the uneven absorbent resin layer could be suppressed. In addition, in Example 3, it was possible to suppress warping and seepage of the test piece.

This application claims priority based on Japanese Patent Application No. 2021-071104 filed on April 20, 2021, and the entire disclosure thereof is incorporated herein.

REFERENCE SIGNS LIST 10 Electronic component 10A Circuit forming surface 10B Electrode 10C Surface opposite to circuit forming surface 20 Base layer 30 Concavo-convex absorbing resin layer 40 Adhesive resin layer 50 Adhesive resin film (adhesive laminate film)
60 structure 70 thermosetting protective film

Claims

An adhesive resin film comprising a substrate layer, an uneven absorbing resin layer, and an adhesive resin layer in this order and used to protect the circuit forming surface of an electronic component,
The minimum value G'bmin of the storage elastic modulus G'b in the range of 25°C or higher and lower than 250°C of the uneven absorbent resin layer is 0.001 MPa or higher and lower than 0.1 MPa, and the storage elastic modulus G'b250 at 250°C. is 0.005 MPa or more and 0.3 MPa or less.
The adhesive resin film according to claim 1,
The adhesive resin film, wherein the loss tangent tan δ of the uneven absorbent resin layer at 250° C. is 0.05 or more and 1.2 or less.
The adhesive resin film according to claim 1 or 2,
The adhesive resin film, wherein the storage elastic modulus G'b30 of the uneven absorbent resin layer at 30°C is 0.1 MPa or more.
The adhesive resin film according to any one of claims 1 to 3,
The adhesive resin film, wherein the uneven absorbent resin layer is a layer containing a crosslinkable resin.
The adhesive resin film according to claim 4,
The adhesive resin film, wherein the crosslinkable resin contains at least one selected from the group consisting of ethylene/α-olefin copolymers and ethylene/vinyl ester copolymers.
The adhesive resin film according to claim 5,
The adhesive resin film, wherein the ethylene-vinyl ester copolymer contains an ethylene-vinyl acetate copolymer.
The adhesive resin film according to any one of claims 1 to 6,
Adhesive resin film that is a bag grind tape.
The adhesive resin film according to any one of claims 4 to 7,
The adhesive resin film, wherein the uneven absorbent resin layer further contains a cross-linking aid.
The adhesive resin film according to claim 8,
The crosslinking aid includes one or more selected from the group consisting of benzophenone compounds, divinyl aromatic compounds, cyanurate compounds, diallyl compounds, acrylate compounds, triallyl compounds, oxime compounds and maleimide compounds. the film.
The adhesive resin film according to any one of claims 1 to 9,
The adhesive resin film, wherein the resin constituting the base material layer contains one or more selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, and polyimide.
The adhesive resin film according to any one of claims 1 to 10,
The adhesive resin film, wherein the resin constituting the base material layer contains polyethylene naphthalate.
The adhesive resin film according to any one of claims 1 to 11,
The adhesive resin film, wherein the thickness of the uneven absorbent resin layer is 10 μm or more and 1000 μm or less.
The adhesive resin film according to any one of claims 1 to 12,
The adhesive constituting the adhesive resin layer is one or more selected from (meth)acrylic adhesives, silicone adhesives, urethane adhesives, olefin adhesives and styrene adhesives. Adhesive resin film, including.
An electronic component having a circuit-forming surface, an adhesive laminated film attached to the circuit-forming surface of the electronic component, and a thermosetting adhesive attached to the surface of the electronic component opposite to the circuit-forming surface. a preparatory step (A) of preparing a structure comprising a protective film;
a thermosetting step (B) of thermosetting the thermosetting protective film by heating the structure;
A method of manufacturing an electronic device comprising
A method for manufacturing an electronic device, wherein the adhesive laminated film is the adhesive resin film according to any one of claims 1 to 13.
A method for manufacturing an electronic device according to claim 14,
The step (A) is
A curing step of thermally curing or ultraviolet curing the irregularity absorbing resin layer of the adhesive film in a state where the adhesive resin film is attached to the circuit forming surface of the electronic component;
a step of attaching the thermosetting protective film to the surface of the electronic component opposite to the circuit forming surface;
A method of manufacturing an electronic device comprising:
A method for manufacturing an electronic device according to claim 15,
A method for manufacturing an electronic device, wherein the heating temperature in the step of attaching the thermosetting protective film to the surface opposite to the circuit forming surface of the electronic component is 50° C. or higher and 90° C. or lower.
17. A method for manufacturing an electronic device according to claim 15 or 16,
In the step (A), before the curing step, in a state in which the adhesive resin film is attached to the circuit forming surface of the electronic component, the surface of the electronic component opposite to the circuit forming surface A method of manufacturing an electronic device, comprising a back-grinding step.
A method for manufacturing an electronic device according to any one of claims 14 to 17,
A method for manufacturing an electronic device, wherein the heating temperature in the step (B) is 120° C. or higher and 170° C. or lower.
A method for manufacturing an electronic device according to any one of claims 14 to 18,
A method of manufacturing an electronic device, wherein the circuit forming surface of the electronic component includes bump electrodes.
A method of manufacturing an electronic device according to claim 19,
A method of manufacturing an electronic device, wherein H/d is 0.01 or more and 1 or less, where H [μm] is the height of the bump electrode and d [μm] is the thickness of the uneven absorbent resin layer.