JP2020115582A - Electronic component mounting substrate and electronic apparatus - Google Patents

Abstract

To provide: an electronic component mounting substrate having a highly reliable electromagnetic wave shield member that is capable of suppressing the occurrence of burr and has excellent PCT resistance; and an electronic apparatus.SOLUTION: An electronic component mounting substrate 51 includes: a substrate 20; an electronic component 30 mounted on at least one surface of the substrate 20; and an electromagnetic wave shield member 1 which is covered from the upper surface of the electronic component 30 to the substrate 20, and covers at least a part of the substrate 20 and the side surface of a stepped portion formed by mounting the electronic component 30. The electromagnetic wave shield member 1 has an electromagnetic wave shield layer 5 containing a binder resin and a conductive filler, and has an indentation elastic modulus of 1-10 GPa.SELECTED DRAWING: Figure 2

Description

The present invention relates to an electronic component mounting board having an electromagnetic wave shield member. The present invention also relates to an electronic device on which the electronic component mounting board is mounted.

An electronic component equipped with an IC chip or the like is usually provided with an electromagnetic wave shield structure in order to prevent malfunction due to a magnetic field or radio waves from the outside. For example, a method is disclosed in which a conductive adhesive film made of an isotropic conductive adhesive and an anisotropic conductive adhesive is coated on a substrate on which electronic components are mounted (Patent Document 1). Further, a method of coating an electromagnetic wave shielding film having a conductive adhesive layer and a base material layer having a specific storage elastic modulus on a substrate on which an electronic component is mounted (Patent Document 2), and showing isotropic conductivity. A method (Patent Document 3) is disclosed in which an electromagnetic wave shield member having a specific tensile breaking strain and having a scale-like particle-containing layer is coated on a substrate on which electronic components are mounted.

International Publication No. 2015/186624 JP, 2014-57041, A International Publication No. 2018/147355

An electronic component mounting substrate is manufactured by coating the substrate on which the electronic component is mounted with an electromagnetic wave shield member by the following method, for example. First, as shown in FIG. 20, the electromagnetic wave shielding laminate 104, which is a laminated body of the electromagnetic wave shielding member 102 and the releasable cushion member 103, is mounted on the top surfaces of the plurality of electronic components 130 mounted on the substrate 120. Place. Next, as shown in FIG. 21, the electromagnetic wave shielding laminate 104 is thermocompression bonded to partially cover the electronic component 130 and the substrate 120 with the electromagnetic wave shielding member 101. After that, as shown in FIG. 22, the releasable cushion member 103 is peeled off, and subsequently, as shown in FIG. 23, a step of dividing the substrate 120 into individual products is performed. In this individualizing step, for example, the electromagnetic wave shield member 101 is brought into contact with the dicing table 141, and while maintaining this contact state, the position facing the groove 125 which is the gap of the electronic component 130 from the substrate 120 side is set. The cutting is performed by cutting the substrate 120 and the electromagnetic wave shield member 101 with the cutting tool 142.

However, in the individualizing step, there is a problem that burrs, which are curling of the electromagnetic wave shield member 101 from the cut surface of the electromagnetic wave shield member 101, are likely to occur (see a partially enlarged view (i) in FIG. 23 ). The main cause of burrs on the electromagnetic wave shield member 101 is high-pressure water washing during dicing in the individualizing step. Further, in the manufactured electronic component mounting substrate, the adhesion between the electromagnetic wave shield member 101 and the substrate 120 or the like may be deteriorated under high humidity and heat conditions. The occurrence of burrs and the decrease in adhesion of the electromagnetic wave shield member 101 cause a decrease in reliability of the electromagnetic wave shield property of the electronic device, which becomes an obstacle when mounting on the circuit board.

The present invention has been made in view of the above problems, and provides an electronic component mounting substrate and an electronic device that have a highly reliable electromagnetic wave shield member that can suppress the occurrence of burrs and that is excellent in pressure cooker test (PCT) resistance. The purpose is to do.

The inventors of the present invention have made extensive studies, and have found that the problems of the present invention can be solved in the following aspects, and have completed the present invention.
[1]: Substrate,
An electronic component mounted on at least one surface of the substrate,
An electromagnetic wave shield member that covers from the upper surface of the electronic component to the substrate and that covers at least a part of the side surface of the step portion formed by mounting the electronic component and the substrate,
The electromagnetic wave shield member has an electromagnetic wave shield layer containing a binder resin and a conductive filler, and has an indentation elastic modulus of 1 to 10 GPa.
[2]: The electronic component mounting board according to [1], wherein the surface layer of the electromagnetic wave shield member has a water contact angle of 70 to 110°.
[3]: In the tape adhesion test after the pressure cooker test based on JIS K5600 of the electromagnetic wave shield member, the electromagnetic wave shield member on the electronic component shows a crosscut residual ratio of 23/25 or more [1] or [2]. ] Electronic component mounting substrate described in.
[4]: The electronic component mounting board according to any one of [1] to [4], which has a kurtosis of 1 to 8 measured according to JIS B0601; 2001 on the surface layer of the electromagnetic wave shield member.
[5]: An electronic device on which the electronic component mounting board according to any one of [1] to [4] is mounted.

According to the present invention, it is possible to provide an electronic component mounting board and an electronic device having a highly reliable electromagnetic wave shield member that can suppress the generation of burrs and that has excellent PCT resistance.

The typical perspective view which shows an example of the electronic component mounting board which concerns on 1st Embodiment. II-II cutting part sectional drawing of FIG. FIG. 6 is a schematic cross-sectional view showing another example of the electronic component mounting board according to the first embodiment. The typical sectional view showing an example of the layered product for electromagnetic waves concerning a 1st embodiment. FIG. 6 is a schematic cross-sectional view showing an example of a manufacturing process of the electronic component mounting board according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing an example of a manufacturing process of the electronic component mounting board according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing an example of a manufacturing process of the electronic component mounting board according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing an example of a manufacturing process of the electronic component mounting board according to the first embodiment. FIG. 4 is a schematic explanatory view for explaining a factor of fluctuation of kurtosis of the electromagnetic wave shield member. FIG. 4 is a schematic explanatory view for explaining a factor of fluctuation of kurtosis of the electromagnetic wave shield member. The typical sectional view showing an example of the layered product for electromagnetic waves concerning a 2nd embodiment. The typical sectional view showing an example of the layered product for electromagnetic wave shields concerning a 3rd embodiment. The schematic cross section which shows an example of the laminated body for electromagnetic wave shields concerning 4th Embodiment. The schematic cross section which shows an example of the manufacturing process of the electronic component mounting board which concerns on 4th Embodiment. The schematic cross section which shows an example of the manufacturing process of the electronic component mounting board which concerns on 5th Embodiment. FIG. 9 is a schematic cross-sectional view showing an example of a manufacturing process of an electronic component mounting board according to a modification. FIG. 3 is a schematic cross-sectional view showing an example of an electronic component mounting board according to the present embodiment. 5 is an electron micrograph of a side surface of the electronic component mounting board according to the third embodiment. 5 is an electron micrograph of a side surface of the electronic component mounting board according to Comparative Example 1. FIG. 6 is a schematic cross-sectional view illustrating a step of coating an electronic component or the like with an electromagnetic wave shield member. FIG. 6 is a schematic cross-sectional view illustrating a step of coating an electronic component or the like with an electromagnetic wave shield member. FIG. 6 is a schematic cross-sectional view illustrating a step of coating an electronic component or the like with an electromagnetic wave shield member. FIG. 6 is a schematic cross-sectional view illustrating a step of coating an electronic component or the like with an electromagnetic wave shield member.

Hereinafter, an example of an embodiment to which the present invention is applied will be described. The numerical values specified in this specification are values obtained by the method disclosed in the embodiment or the example. Further, the numerical values “A to B” specified in this specification refer to ranges satisfying the numerical values A and the values larger than the numerical value A and the numerical values B and the values smaller than the numerical value B. In addition, the sheet in this specification includes not only a sheet defined by JIS but also a film. For clarity of explanation, the following description and drawings are simplified as appropriate. Unless otherwise noted, the various components appearing in this specification may be used alone or in combination of two or more.

[First Embodiment]
<Electronic component mounting board>
FIG. 1 is a schematic perspective view showing an example of the electronic component mounting board according to the first embodiment, and FIG. 2 is a sectional view taken along the line II-II of FIG. The electronic component mounting board 51 includes the substrate 20, the electronic component 30, the electromagnetic wave shield member 1, and the like.

The substrate 20 may be any substrate as long as it can mount the electronic component 30 and can withstand the thermocompression bonding process described later, and can be arbitrarily selected. For example, a work board having a conductive pattern made of copper foil or the like formed on the surface or inside thereof, a mounted module board, a printed wiring board, or a build-up board formed by a build-up method or the like can be mentioned. Alternatively, a film or sheet-shaped flexible substrate may be used. The conductive pattern is, for example, an electrode/wiring pattern (not shown) for electrically connecting to the electronic component 30, and a ground pattern 22 for electrically connecting to the electromagnetic wave shield member 1. Electrodes/wiring patterns, vias (not shown) and the like can be arbitrarily provided inside the substrate 20. The substrate 20 may be not only a rigid substrate but also a flexible substrate.

In the example of FIG. 1, the electronic components 30 are arranged in a 5×4 array on the substrate 20. The electromagnetic wave shield member 1 is provided so as to cover the exposed surfaces of the substrate 20 and the electronic component 30. That is, the electromagnetic wave shield member 1 is coated so as to follow the irregularities formed by the electronic component 30. The electromagnetic wave shield member 1 shields unnecessary radiation generated from the signal wiring and the like built in the electronic component 30 and/or the substrate 20, and can prevent malfunction due to a magnetic field or radio waves from the outside.

The number, arrangement, shape and type of electronic components 30 are arbitrary. Instead of arranging the electronic components 30 in an array, the electronic components 30 may be arranged at arbitrary positions. When the electronic component mounting substrate 51 is divided into unit modules, as shown in FIG. 2, the half dicing groove 25 may be provided so as to partition the unit modules in the thickness direction of the substrate from the upper surface of the substrate. The electronic component mounting board according to the first embodiment includes both a board before being divided into unit modules and a board after being divided into unit modules. That is, in addition to the electronic component mounting substrate 51 on which a plurality of unit modules (electronic components 30) are mounted as shown in FIGS. 1 and 2, the electronic component mounting substrate 52 after being divided into unit modules as shown in FIG. Also includes. Of course, an electronic component mounting substrate in which one electronic component 30 is mounted on the substrate 20 and covered with an electromagnetic wave shield member without undergoing the individualizing step is also included. That is, in the electronic component mounting board according to the first embodiment, at least one electronic component is mounted on the substrate, and at least a part of the step portion formed by mounting the electronic component is covered with the electromagnetic wave shield member. Comprehensive structure.

The electronic component 30 includes all components in which electronic elements such as a semiconductor integrated circuit are integrally covered with an insulator. For example, there is a mode in which a semiconductor chip 31 (see FIG. 3) on which an integrated circuit (not shown) is formed is molded with a sealing material (mold resin 32). The substrate 20 and the semiconductor chip 31 are electrically connected to the wiring or the electrode 21 formed on the substrate 20 via these contact areas, or via the bonding wires 33, solder balls (not shown) and the like. Examples of electronic components include semiconductor chips, inductors, thermistors, capacitors and resistors.

The electronic component 30 and the substrate 20 according to the first embodiment can be widely applied to known aspects. In the example of FIG. 3, the semiconductor chip 31 has solder balls 24 connected to the back surface of the substrate 20 via inner vias 23. In addition, a ground pattern 22 for electrically connecting to the electromagnetic wave shield member 1 is formed in the substrate 20. Further, as in a fourth embodiment described later, a plurality of electronic components 30 may be mounted on the electronic component mounting substrate after being singulated or the electronic component mounting substrate that is not singulated (FIG. 14C). reference). In addition, a single or a plurality of electronic elements or the like can be mounted in the electronic component 30.

<Electromagnetic wave shield member>
The electromagnetic wave shield member 1 is obtained by placing the electromagnetic wave shielding laminate on the top surface of the electronic component 30 mounted on the substrate 20 and coating the electronic component 30 and the substrate 20 by thermocompression bonding. The electromagnetic wave shield member 1 is covered from the upper surface of the electronic component 30 to the substrate 20, and covers the side surface of the step portion formed by mounting the electronic component 30 and at least a part of the substrate 20. It is not essential to cover the entire surface on which the electronic component 30 is mounted. The electromagnetic wave shield member 1 is connected to a ground pattern 22 exposed on the side surface or the upper surface of the substrate 20 and/or a ground pattern (not shown) such as a connection wiring of the electronic component 30 in order to sufficiently exert the shielding effect. Is preferred.

The electromagnetic wave shield member 1 can be formed by using an electromagnetic wave shield laminate. FIG. 4 shows a schematic cross-sectional view of the electromagnetic wave shielding laminate. The electromagnetic wave shield laminate 4 according to the first embodiment includes an electromagnetic wave shield member 2 and a releasable cushion member 3. The electromagnetic wave shielding member 2 is composed of a single layer of the conductive adhesive layer 6 in the first embodiment. The conductive adhesive layer 6 is bonded to the electronic component 30 and the substrate 20 by thermocompression bonding to form the electromagnetic wave shield layer 5. In the first embodiment, the electromagnetic wave shield layer 5 functions as the electromagnetic wave shield member 1.

The electromagnetic wave shield member 2 is formed of a laminate of two or more conductive adhesive layers as in the second embodiment described later, or is formed of a conductive adhesive layer and a hard coat layer as in the third embodiment. It may be formed of a laminated body of other layers such as a laminated body or a laminated body of an insulating adhesive layer and a conductive adhesive layer as in the fourth embodiment. The electromagnetic wave shield member 1 obtained by thermocompression bonding the electromagnetic wave shield member 2 is composed of a laminated body of two or more electromagnetic wave shield layers in the second embodiment, and is composed of an electromagnetic wave shield layer and a hard coat layer in the third embodiment. It is composed of a laminated body, and in the fourth embodiment, it is composed of a laminated body of an insulating coating layer and an electromagnetic wave shielding layer. Thus, the electromagnetic wave shield member may be composed of a laminate of the electromagnetic wave shield layer and other layers.

The electromagnetic wave shield layer 5 contains a binder resin and a conductive filler. The conductive filler in the electromagnetic wave shield layer 5 is in continuous contact with the conductive filler and exhibits conductivity. From the viewpoint of enhancing the electromagnetic wave shielding property, the sheet resistance value of the electromagnetic wave shielding layer 5 is preferably 1Ω/□ or less.

The electromagnetic wave shield member 1 has an indentation elastic modulus of 1 to 10 GPa. By setting the indentation elastic modulus within this range, it is possible to suppress local minute deformation of the electromagnetic wave shield member 1 due to stress, and as a result, it is possible to effectively suppress damage due to the occurrence of burrs on the electromagnetic wave shield member 1. Furthermore, since the PCT resistance is excellent, it is possible to effectively suppress the decrease in adhesion after the reflow process. Therefore, a high-quality electronic component mounting board can be provided.

By setting the indentation elastic modulus of the electromagnetic wave shield member 1 to 1 GPa or more, the deformation of the electromagnetic wave shield member 1 against the stress received from the cutting tool such as the dicing blade in the cutting process is suppressed, and the electromagnetic wave shield member 1 produced in the manufacturing process is suppressed. Burrs (see (i) in FIG. 23) can be effectively suppressed. In addition, the burr mentioned in the present specification refers to turning of the electromagnetic wave shield member based on the cut surface of the electromagnetic wave shield member 1.

The indentation elastic modulus of the electromagnetic wave shield member 1 can be adjusted by the composition of the electromagnetic wave shield member 2 in the electromagnetic wave shield laminate 4 to be described later before thermocompression bonding. More specifically, it can be adjusted by the kind of the binder resin precursor in the composition of the electromagnetic wave shielding member 2 before thermocompression bonding for forming the electromagnetic wave shielding member 1, the blending amount of each component, and the like. Specifically, the indentation elastic modulus tends to increase as the filler content increases. In addition, the indentation elastic modulus tends to increase by increasing the number of functional groups of the resin used as the binder resin precursor or the content of the curable compound. Further, the higher the hardness of the binder resin, the larger the indentation elastic modulus tends to be. Therefore, it is preferable to make the kind of the binder resin precursor for forming the binder resin or the crosslink density of the binder resin appropriate. The crosslink density can be easily adjusted by the types of resins and curable compounds and the number of functional groups.

The indentation elastic modulus can also be considered as the Young's modulus which represents the property of the material to be deformed by external stress. The “indentation elastic modulus” in the present specification refers to a value obtained by the measuring method and the measuring condition described in Examples described later.

A more preferable range of the indentation elastic modulus of the electromagnetic wave shield member 1 is more than 1.5 GPa and 8 GPa or less, and a more preferable range is 2 GPa or more and 7.4 GPa or less.

The film thickness of the electromagnetic wave shield member 1 can be appropriately selected depending on the application. For applications where thinning is required, the thickness T1 and T2 of the electromagnetic wave shield member 1 that covers the upper surface of the electronic component can be set to, for example, about 10 to 200 μm.

Product information may be stamped on the electronic component 30. In that case, there are a method of forming the electromagnetic wave shield member 1 after marking on the electronic component 30 and a method of forming the electromagnetic wave shield member 1 on the electronic component 30 and then marking on the electromagnetic wave shield member. In any case, good visibility of the marking is required while maintaining high shielding property. From the viewpoint of satisfying both characteristics, the film thickness T1 of the electromagnetic wave shield member is preferably 10 μm or more, more preferably 20 μm or more. In the latter marking method, that is, in the case of marking on the electromagnetic wave shield member, there is no upper limit of the film thickness of the electromagnetic wave shield member. On the other hand, in the former marking method, that is, when directly marking on an electronic component, the upper limit of the film thickness T1 of the electromagnetic wave shield member is preferably 50 μm or less, and more preferably 30 μm or less in order to maintain the visibility of the marking.

The water contact angle of the surface layer of the electromagnetic wave shield member 1 is preferably 70 to 110°. By setting this range, it is possible to more effectively suppress damage to the electromagnetic wave shield layer during the manufacturing process. Further, when the releasable cushion member filled in the groove-shaped recess formed in the half dicing groove 25 of the electronic component 30 is peeled from the electromagnetic wave shield member 1, it is possible to suppress the occurrence of burrs. The more preferable range of the water contact angle of the electromagnetic wave shield member is 75 to 105°, and the more preferable range is 80 to 100°. The water contact angle of the electromagnetic wave shield member can be adjusted by adjusting the amount of the surface conditioner added to the composition forming the electromagnetic wave shield member. The value of the water contact angle tends to increase as the amount of the surface conditioner added to the electromagnetic wave shield member 1 increases.

In order to make the pressure cooker (hereinafter, also referred to as PCT) test resistance more excellent, it is preferable that the electromagnetic shield member 1 has a Martens hardness of 50 N/mm ² or more. When the indentation elastic modulus of the electromagnetic wave shield member 1 is set in the range of 1 to 10 GPa and the Martens hardness of 50 N/mm ² or more is combined, the adhesion after the pressure cooker test becomes more excellent. As a result, it is possible to provide the electromagnetic wave shield member 1 having excellent adhesion even after reflow. Martens hardness is more preferably 60N / mm ² or more, 70N / mm ² or more is more preferable.

The Martens hardness can be adjusted by the hardness of the conductive filler and the binder component. The hardness of the binder component mainly depends on the hardness of the cured product of the thermosetting resin and the curable compound. Specifically, the addition of scale-like particles tends to increase the Martens hardness, and the addition of spherical or dendrite-like particles tends to decrease the Martens hardness. Further, as the amount of conductive filler increases, the Martens hardness tends to increase. Further, the higher the hardness of the cured resin, the harder the Martens hardness.

Although a manufacturing method will be described later, from the viewpoint of enhancing releasability when the releasable cushion member is peeled from the electromagnetic wave shield member 1 after the electromagnetic wave shield laminate 4 is thermocompression bonded to the substrate 20 on which the electronic component 30 is mounted. It is preferable that the kurtosis of the surface layer of the electromagnetic wave shield member 1 measured according to JIS B0601; 2001 is 8 or less. It is considered that when it is 8 or less, the sharpness of the surface shape of the electromagnetic wave shield member 1 becomes appropriate, and the release cushion member 3 and the electromagnetic wave shield member 1 are easily separated. As a result, it is possible to effectively suppress the phenomenon that the releasable cushion member 3 is torn in the half dicing groove 25 in the gap between the electronic components and remains as a residue. In the present specification, the “removable” cushion member is a releasable cushion member that is torn when the releasable cushion member is peeled and remains in a groove that is a gap between electronic components.

Further, from the viewpoint of enhancing the scratch resistance, it is preferable that the electromagnetic wave shield member 1 has a kurtosis of 1 or more. By setting it to 1 or more, the resistance to steel wool can be improved. The more preferable range of the kurtosis of the electromagnetic wave shield member is 1.5 to 6.5, and the more preferable range thereof is 2 to 4.

The electromagnetic wave shield member 1 preferably has a kurtosis of 1 to 8 measured on the surface layer according to JIS B0601; 2001. Here, the kurtosis is an index showing the roughness curve of the surface unevenness expressed by the mathematical expression (1), and represents the flatness and the sharpness of the height distribution.
Here, L is a reference length. Further, Rq is a root mean square height, and is represented by the following mathematical expression (2), where Z(x) is a surface height change along one axis (x axis).

Kurtosis shows the quartic mean of Z(x) in the standard length made dimensionless by the quadratic of the root mean square height Rq. When the kurtosis is 3, it indicates that the distribution of the sharpness of the convex portion (or the concave portion) is close to the normal distribution. The number of sharp pointed protrusions (or recesses) with respect to the reference height Rq increases as the kurtosis becomes larger than 3, and the steep pointed protrusions (or recesses) becomes smaller as the kurtosis becomes smaller than 3. Indicates that the number of

Although the manufacturing method will be described later, when the electromagnetic wave shielding laminate 4 is thermocompression bonded to the substrate on which the electronic component 30 is mounted, the half dicing groove 25 is separated when the releasable cushion member 3 is separated from the electromagnetic wave shielding member 1. The shape cushion member 3 is peeled off while sliding almost vertically. Since the releasable cushion member 3 easily breaks due to the anchoring effect, a technique for suppressing this is required. As a result of intensive studies by the present inventors, it has been found that the shape control of the contact interface of the electromagnetic wave shield member 1 is important, and the above range of kurtosis is suitable as this shape.

The root mean square height of the surface of the electromagnetic wave shield member 1 is preferably in the range of 0.4 to 1.6 μm, more preferably 0.5 to 1.5 μm, and 0.7 to 1.2 μm. More preferably. In the present specification, the kurtosis and the root mean square height refer to values obtained by the method described in Examples below.

The kurtosis on the surface of the electromagnetic wave shield member 1 can be adjusted by the manufacturing process of the electromagnetic wave shield member 2 in the electromagnetic wave shield laminate 4. Further, it can be adjusted by the kind of each component in the composition of the electromagnetic wave shielding member 2 before thermocompression bonding for forming the electromagnetic wave shielding member 1 and the compounding amount thereof. Details will be described later. Note that the inventors of the present invention have made extensive studies, and by adding an amount of a conductive filler that can function as an electromagnetic wave shield layer, the value of kurtosis does not substantially change before or after the reflow treatment, or even if it changes. It was confirmed that the amount of change was small.

<Method for manufacturing electronic component mounting board>
Hereinafter, an example of a method of manufacturing the electronic component mounting board of the first embodiment will be described with reference to FIGS. However, the manufacturing method of the electronic component mounting board of the present invention is not limited to the following manufacturing method.

The method of manufacturing an electronic component mounting board according to the first embodiment includes [a] a step of mounting the electronic component 30 on the substrate 20, and [b] a laminated body 4 for electromagnetic wave shielding on the substrate 20 on which the electronic component 30 is mounted. And [c] joining the electromagnetic wave shield member 1 by thermocompression bonding so as to follow at least part of the side surface of the step formed by mounting the electronic component 30 and the exposed surface of the substrate 20. , [D] a step of peeling the releasable cushion member 3, and [e] a step of dividing the electronic component mounting board 51 into individual pieces. Hereinafter, each step will be described.

[A] Step of mounting electronic components on the substrate:
First, the electronic component 30 is mounted on the substrate 20. For example, a semiconductor chip (not shown) is mounted on the substrate 20, and the substrate 20 on which the semiconductor chip is formed is molded with a sealing resin so that the inside of the substrate 20 is reached from above the electronic components 30. The mold resin and the substrate 20 are half-cut by dicing or the like. A method of arranging the electronic components 30 in an array on the substrate 20 that is half-cut in advance may be used. Through these steps, for example, the substrate 20 on which the electronic component 30 is mounted as shown in FIG. 5 is obtained. In the example of FIG. 5, the electronic component 30 refers to an integrated body obtained by molding a semiconductor chip, and refers to all electronic elements protected by an insulator. The half-cut includes a mode of reaching the inside of the substrate 20 and a mode of cutting to the surface of the substrate 20. Also, the entire substrate 20 may be cut at this stage. In this case, it is preferable that the substrate 20 is placed on the adhesive tape-attached substrate so as not to cause positional deviation. The material of the sealing resin for molding is not particularly limited, but a thermosetting resin is usually used. The method for forming the sealing resin is not particularly limited, and examples thereof include printing, laminating, transfer molding, compression, casting and the like. Molding is arbitrary, and the mounting method of the electronic component 30 can be changed arbitrarily.

[B] Step of placing the electromagnetic wave shielding laminate on the substrate:
Next, the electromagnetic wave shielding laminate 4 is prepared in which the substrate 20 on which the electronic component 30 is mounted is melted by thermocompression bonding and coated (see FIG. 4 ). The electromagnetic wave shielding laminate 4 is placed on the top surface of the electronic component 30 so that the conductive adhesive layer 6 of the electromagnetic wave shielding laminate 4 is on the electronic component 30 side. At this time, the electromagnetic wave shielding laminate 4 may be temporarily attached to a part or the whole surface of the electronic component 30. The term "temporary attachment" refers to a state in which the conductive adhesive layer 6 is fixed to an adherend at the B stage, which is temporarily joined so as to come into contact with the upper surface of at least a part of the electronic component 30. As the peeling force, in the 90° peel test, the peeling force with respect to Kapton 200 is preferably about 1 to 5 N/cm. An example of the temporary attachment method is a method of placing the electromagnetic wave shielding laminate 4 on the substrate 20 on which the electronic component 30 is mounted and lightly thermocompressing the entire surface or the end portion with a heat source such as an iron to temporarily attach. A plurality of electromagnetic wave shielding laminates 4 may be used for each region of the substrate 20 depending on the manufacturing equipment or the size of the substrate 20. Further, the electromagnetic wave shielding laminate 4 may be used for each electronic component 30. From the viewpoint of simplifying the manufacturing process, it is preferable to use one electromagnetic wave shielding laminate 4 for the entire plurality of electronic components 30 mounted on the substrate 20.

[C] Step of forming electromagnetic wave shield member:
Subsequently, the electromagnetic wave shielding laminate 4 is sandwiched between the pair of press substrates 40 on the substrate 20 on which the electronic component 30 is mounted and thermocompression bonded (see FIG. 6 ). In the electromagnetic wave shielding laminate 4, the conductive adhesive layer 6 and the releasable cushion member 3 are melted by heat and stretched along the half-cut groove provided in the production substrate by pressing, and the electronic component 30 and the substrate are obtained. It is coated following 20. The conductive adhesive layer 6 is bonded to the electronic component 30 and the substrate 20 and also functions as the electromagnetic wave shield layer 5 by thermocompression bonding. In the first embodiment, the electromagnetic wave shield member 1 is composed of a single layer of the electromagnetic wave shield layer 5, so that the electromagnetic wave shield member 1 is obtained by thermocompression bonding the conductive adhesive layer 6. After thermocompression bonding, a separate heat treatment may be performed for the purpose of promoting heat curing.

When the electromagnetic wave shielding laminate 4 is heated and pressed, a heat softening member, cushion paper or the like may be used between the electromagnetic wave shielding laminate 4 and the press substrate 40, if necessary.

The temperature and pressure in the thermocompression bonding process can be arbitrarily set independently within the range in which the coverage of the conductive adhesive layer 6 can be secured, depending on the heat resistance and durability of the electronic component 30, the manufacturing equipment or needs. The pressure range is not limited, but is preferably about 0.1 to 5.0 MPa, more preferably 0.5 to 2.0 MPa. By releasing the press board 40, a production board as shown in FIG. 7 is obtained. In this way, the electromagnetic shield member 1 covers the top and side surfaces of the electronic component and the exposed surface of the substrate.

The heating temperature in the thermocompression bonding step is preferably 100° C. or higher, more preferably 110° C. or higher, even more preferably 120° C. or higher. Although the upper limit value depends on the heat resistance of the electronic component 30, it is preferably 220° C., more preferably 200° C., and further preferably 180° C.

The thermocompression bonding time can be set according to the heat resistance of the electronic component 30, the binder resin used for the electromagnetic wave shield member 1, the production process, and the like. When a thermosetting resin is used as the binder resin precursor, the range of about 1 minute to 2 hours is suitable. The thermocompression bonding time is more preferably about 1 minute to 1 hour. The thermosetting resin is cured by this thermocompression bonding. However, the thermosetting resin may be partially or substantially completely cured before thermocompression bonding as long as it can flow.

The thickness of the conductive adhesive layer 6 is such that the electromagnetic wave shield layer 5 can be formed by covering the top and side surfaces of the electronic component 30 and the exposed surface of the substrate 20. Although it may vary depending on the fluidity of the binder resin precursor used and the distance and size between the electronic components 30, it is usually preferably about 10 to 200 μm, more preferably about 15 to 100 μm, still more preferably about 20 to 70 μm. This makes it possible to effectively exhibit the electromagnetic wave shielding property while improving the coverage with the sealing resin.

The releasable cushion member 3 has a function of softening to promote the coating of the conductive adhesive layer 6 to cover the top and side surfaces of the electronic component 30 and the exposed surface of the substrate 20, and the releasability in the peeling step. It is possible to use a material having excellent properties. As an upper layer of the releasable cushion member 3, a heat softening member functioning as a cushion material may be used, if necessary. In the example of the first embodiment, the coating of the electromagnetic wave shield member 1 electrically connects the ground pattern 22 formed in the substrate 20 and the electromagnetic wave shield member 1 (see FIG. 7).

The conductive adhesive layer 6 contains a binder resin precursor and a conductive filler. Examples of the binder resin precursor include a thermoplastic resin, a self-crosslinking resin, a plurality of types of reactive resins, and a mixture of a curable resin and a crosslinking agent. You may use these in combination. When a thermoplastic resin is exclusively used as the binder resin precursor, it can be said that the binder resin precursor and the binder resin are substantially the same in the sense that they do not have a crosslinked structure. From the viewpoint of enhancing tape adhesion after PCT, it is preferable that the binder resin forming the electromagnetic wave shield layer 5 has a three-dimensional crosslinked structure.

[D] Step of peeling the releasable cushion member:
The releasable cushion member 3 covering the upper layer of the electromagnetic wave shield member 1 is peeled off. Thus, the electronic component mounting board 51 having the electromagnetic wave shield member 1 that covers the electronic component 30 is obtained (see FIGS. 1 and 2). For example, peeling of the releasable cushion member 3 may be manually peeled from the end portion, or the outer surface of the releasable cushion member 3 may be sucked and peeled from the electromagnetic wave shield member 1. Peeling by suction is preferable from the viewpoint of improving the yield by automation.

[E] Process of dividing into individual pieces:
Using a cutting tool such as a dicing blade, dicing is performed in the X direction and the Y direction at a position corresponding to the product area of the individual product of the electronic component mounting board 51 (see FIG. 2). Through these steps, the electronic component 30 is covered with the electromagnetic wave shield member 1, and the ground pattern 22 formed on the substrate 20 and the electromagnetic wave shield member 1 are electrically connected to each other. 51 is obtained. The dicing method is not particularly limited as long as it can be separated into individual pieces. Dicing is performed from the substrate 20 side or the electromagnetic wave shielding laminate 4 side. At the time of dicing, high pressure water washing may be performed in order to cool friction heat and wash away dicing dust generated by dicing. In the electronic component mounting board 51 according to the present embodiment, the indentation elastic modulus is set to 1 to 10 GPa. By doing so, peeling of the electromagnetic wave shield member 1 due to the impact of high-pressure water washing can be significantly improved.

<Laminate for electromagnetic wave shield>
The electromagnetic wave shielding laminate 4 of the first embodiment is composed of two layers, that is, the electromagnetic wave shielding member 2 and the releasable cushion member 3, as described in FIG. In the first embodiment, the electromagnetic wave shielding member 2 is composed of a single-layer conductive adhesive layer 6. The conductive adhesive layer 6 is bonded to the electronic component 30 and the substrate 20 through a thermocompression bonding process, and functions as the electromagnetic wave shield layer 5.

(Conductive adhesive layer)
The conductive adhesive layer 6 is a layer formed from a resin composition containing a binder resin precursor and a conductive filler. The binder resin precursor contains at least a thermosoftening resin. Examples of the thermosoftening resin include a thermoplastic resin, a thermosetting resin and an actinic ray curable resin. The thermosetting resin and the actinic ray curable resin usually have a reactive functional group. When a thermosetting resin is used, a curable compound and a thermosetting auxiliary can be used together. When an actinic ray curable resin is used, a photopolymerization initiator, a sensitizer and the like can be used in combination. A thermosetting type that cures at the time of thermocompression bonding is preferable from the viewpoint of simplicity of the manufacturing process.
Alternatively, a self-crosslinking resin or a plurality of resins that crosslink each other may be used. In addition to these resins, a thermoplastic resin may be mixed. The compounding components such as the resin and the curable compound may be used alone or in combination of two or more.
Incidentally, a part of the crosslinks may be formed at the stage of the conductive adhesive layer 6 to be in the B stage (semi-cured state). For example, a state in which the thermosetting resin and a part of the curable compound are reacted and semi-cured may be included.

Suitable examples of the heat softening resin, polyurethane resin, polycarbonate resin, styrene elastomer resin, phenoxy resin, polyurethane urea resin, polyimide resin, polyamide resin, polycarbonate imide resin, polyamide imide resin, epoxy resin, epoxy ester resin, Acrylic resins, polyester resins, polystyrene, polyesteramide resins and polyetherester resins can be mentioned. The thermosetting resin when used under severe conditions during reflow should contain at least one of an epoxy resin, an epoxy ester resin, a urethane resin, a urethane urea resin, and a polyamide. preferable.

Among these, polyurethane resin, polycarbonate resin, styrene elastomer resin, phenoxy resin, polyamide resin, and polyimide resin are preferable. Further, a resin having a polycarbonate skeleton represented by the general formula (1) in the resin is preferable.
-RO-CO-O-... General formula (1)
In the formula, R is a divalent organic group.
By using the resin having the polycarbonate skeleton, it is possible to effectively suppress the burr of the electromagnetic wave shield layer caused by the manufacturing process. The heat softening resin can be used alone or in combination of two or more at an arbitrary ratio.

Examples of the resin having a polycarbonate skeleton include a polycarbonate resin, a polyurethane resin having a polycarbonate skeleton, a polyamide resin, and a polyimide resin. For example, according to the polycarbonate imide resin, having a polyimide skeleton makes it possible to enhance heat resistance, insulating properties and chemical resistance. On the other hand, by having a polycarbonate skeleton, flexibility and adhesion can be effectively enhanced.

Examples of the polycarbonate urethane resin include 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, and 2-methyl-1,8-octanediol. Polycarbonate polyols based on one or more diols such as the above can be used as the polyol component.

The thermosoftening resin, as a thermosetting resin, may have a plurality of functional groups that can be used for a crosslinking reaction by heating. Functional groups include, for example, hydroxyl group, phenolic hydroxyl group, carboxyl group, amino group, epoxy group, oxetanyl group, oxazoline group, oxazine group, aziridine group, thiol group, isocyanate group, blocked isocyanate group, silanol group and the like. ..

The curable compound has a functional group capable of crosslinking with the reactive functional group of the thermosetting resin. By crosslinking, the adhesion can be made stronger and the water resistance can be improved. Curable compounds include epoxy compounds, acid anhydride group-containing compounds, isocyanate compounds, polycarbodiimide compounds, aziridine compounds, dicyandiamide compounds, amine compounds such as aromatic diamine compounds, phenol compounds such as phenol novolac resins, and organometallic compounds. preferable. The curable compound may be a resin. In this case, the thermosetting resin and the curable compound are distinguished from each other such that one having a larger content is a thermosetting resin and one having a smaller content is a curable compound.

The epoxy compound is a compound having two or more epoxy groups in one molecule. The properties of the epoxy compound may be liquid or solid. As the epoxy compound, for example, a glycidyl ether type epoxy compound, a glycidyl amine type epoxy compound, a glycidyl ester type epoxy compound, a cycloaliphatic (alicyclic) epoxy compound and the like are preferable.

Examples of the glycidyl ether type epoxy compound include a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a bisphenol S type epoxy compound, a bisphenol AD type epoxy compound, a cresol novolac type epoxy compound, a phenol novolac type epoxy compound, and α-naphthol novolak. Type epoxy compound, bisphenol A type novolac type epoxy compound, dicyclopentadiene type epoxy compound, tetrabromobisphenol A type epoxy compound, brominated phenol novolac type epoxy compound, tris(glycidyloxyphenyl)methane, tetrakis(glycidyloxyphenyl)ethane Etc.

Examples of the glycidyl amine type epoxy compound include tetraglycidyl diaminodiphenylmethane, triglycidyl paraaminophenol, triglycidyl metaaminophenol, and tetraglycidyl metaxylylenediamine.

Examples of the glycidyl ester type epoxy compound include diglycidyl phthalate, diglycidyl hexahydrophthalate, diglycidyl tetrahydrophthalate, and the like.

Examples of the cycloaliphatic (alicyclic) epoxy compound include epoxycyclohexylmethyl-epoxycyclohexanecarboxylate and bis(epoxycyclohexyl)adipate. Further, a liquid epoxy compound can be preferably used.

Examples of the imidazole compound include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2,4-dimethylimidazole, 2-phenylimidazole, and other imidazole compounds, and further imidazole compounds. There are latent curing accelerators having improved storage stability, such as a type in which an epoxy resin is reacted with a solvent to make it insoluble in a solvent, or a type in which an imidazole compound is encapsulated in microcapsules. Among these, a conductive adhesive layer The latent curing accelerator is preferable from the viewpoint of initiating the curing after the heat melting.

The structure and molecular weight of the curable compound can be appropriately designed depending on the application. From the viewpoint of effectively suppressing burrs by adjusting the indentation elastic modulus in the range of 1 to 10 GPa, it is preferable to use two or more curable compounds having different molecular weights. The use of the first curable compound and the second curable compound also has the effect of increasing the tensile breaking strain of the electromagnetic wave shield layer.

The curable compound is preferably contained in an amount of 1 to 70 parts by mass, more preferably 3 to 65 parts by mass, still more preferably 3 to 60 parts by mass, relative to 100 parts by mass of the thermosetting resin. When the first curable compound and the second curable compound are used in combination, the first curable compound is preferably contained in an amount of 5 to 50 parts by mass, and preferably 10 to 40 parts by mass with respect to 100 parts by mass of the thermosetting resin. More preferably, it is more preferable to contain 20 to 30 parts by mass. On the other hand, the second curable compound is preferably contained in an amount of 0 to 40 parts by mass, more preferably 5 to 30 parts by mass, and further preferably 10 to 20 parts by mass based on 100 parts by mass of the thermosetting resin.

Preferable examples of the thermoplastic resin include polyester, acrylic resin, polyether, urethane resin, styrene elastomer, polycarbonate, butadiene rubber, polyamide, ester amide resin, polyisoprene, and cellulose. Examples of the tackifying resin include rosin-based resins, terpene-based resins, alicyclic petroleum resins, and aromatic petroleum resins. In addition, a conductive polymer can be used. Examples of the conductive polymer include polyethylenedioxythiophene, polyacetylene, polypyrrole, polythiophene, and polyaniline. Preferable examples of the thermoplastic resin include polyester, acrylic resin, polyether, urethane resin, styrene elastomer, polycarbonate, butadiene rubber, polyamide, ester amide resin, polyisoprene, and cellulose.

Examples of the conductive filler include metal filler, conductive ceramic particles and a mixture thereof. Examples of the metal filler include core powders of metal powder such as gold, silver, copper and nickel, alloy powder such as solder, silver coated copper powder, gold coated copper powder, silver coated nickel powder and gold coated nickel powder. From the viewpoint of obtaining excellent conductive properties, a conductive filler containing silver is preferable. From the viewpoint of cost, silver-coated copper powder obtained by coating copper powder with silver is particularly preferable.

The silver content in the silver-coated copper is preferably 3 to 20% by mass, more preferably 8 to 17% by mass, and further preferably 10 to 15% by mass, based on 100% by mass of the total amount of silver and copper. In the case of core-shell type particles, the coverage of the coating layer on the core portion is preferably 60% or more on average, more preferably 70% or more, and further preferably 80% or more. The core portion may be non-metal, but from the viewpoint of conductivity, a conductive substance is preferable, and metal particles are more preferable.

An electromagnetic wave absorbing filler may be used as the conductive filler. For example, iron, Fe-Ni alloy, Fe-Co alloy, Fe-Cr alloy, Fe-Si alloy, Fe-Al alloy, Fe-Cr-Si alloy, Fe-Cr-Al alloy, Fe-Si-Al alloy, etc. Examples include iron-based alloys, Mg-Zn ferrite, Mn-Zn ferrite, Mn-Mg ferrite, Cu-Zn ferrite, Mg-Mn-Sr ferrite, Ni-Zn ferrite, and other ferrite-based materials, and carbon filler. Examples of the carbon filler include acetylene black, Ketjen black, furnace black, carbon black, carbon fiber, particles composed of carbon nano-nanotubes, graphene particles, graphite particles and carbon nanowalls.

Examples of the shape of the conductive filler used in the conductive adhesive layer include scale particles, dendrite (dendritic) particles, needle particles, plate particles, grape particles, fibrous particles, and spherical particles. From the viewpoint of adjusting the numerical value of the kurtosis, it is preferable to include a conductive filler of needle-shaped particles and/or dendrite-shaped particles. Here, the acicular shape means that the major axis is three times or more the minor axis, and includes a so-called needle shape, a spindle shape, a columnar shape and the like. Further, the dendrite shape means a shape in which a plurality of branched branches extend two-dimensionally or three-dimensionally from a rod-shaped main axis when observed with an electron microscope (500 to 20,000 times). In the dendrite shape, the branched branch may be bent, or the branched branch may further extend from the branched branch.

Further, by containing the scale-like particles as the conductive filler, it is possible to provide an electromagnetic wave shield member having excellent coverage. Here, the scaly shape includes a thin shape and a plate shape. The conductive filler may have a scaly shape as a whole particle, and may have an elliptical shape, a circular shape, or a cut around the fine particle. The scale-like particles tend to have a high Martens hardness, and the spherical and dendritic particles tend to have a low Martens hardness. Further, as the amount of conductive filler increases, the Martens hardness tends to increase. Further, the higher the hardness of the cured resin, the harder the Martens hardness.

The conductive filler may be used alone or as a mixture. For example, a combination of scaly particles and spherical particles, a combination of scaly particles and dendrite particles, a combination of scaly particles and acicular particles, a combination of scaly particles, dendrite particles and acicular particles can be exemplified. These may also be used in combination with nano-sized spherical particles.

Further, by using the dendrite-shaped particles and/or the acicular particles in combination, the number of contact points between the conductive fillers can be increased, and the shield characteristics can be improved. In addition, the combined use of dendrite particles and/or acicular particles can increase the contact area with the binder component, so that a high-quality electromagnetic wave shield member can be provided.

The content of the conductive filler is preferably 40 to 85% by mass, and more preferably 50 to 80% by mass in the solid content (100% by mass) of the thermosoftening resin composition layer.

It is preferable that the acicular particles and/or dendrite particles are contained in an amount of 50% by mass or less with respect to 100% by mass of the conductive filler in the conductive adhesive layer. It is more preferably 0.5 to 40% by mass, further preferably 1 to 35% by mass, and particularly preferably 1 to 30% by mass. By containing 50% by mass or less, it is possible to provide an electromagnetic wave shield member having more excellent scratch resistance.

The average particle diameter D50 of the scaly particles is preferably 2 to 100 μm. A nano-sized conductive filler may be mixed with the scaly particles.

The average particle diameter D50 of the acicular particles is preferably 2 to 100 μm, more preferably 2 to 80 μm. The thickness is more preferably 3 to 50 μm, and particularly preferably 5 to 20 μm. Similarly, the preferable range of the average particle diameter D50 of the dendrite-shaped particles is preferably 2 to 100 μm, more preferably 2 to 80 μm. The thickness is more preferably 3 to 50 μm, and particularly preferably 5 to 20 μm. The average particle diameter D50 of the scaly particles is preferably 2 to 100 μm, more preferably 2 to 80 μm. The thickness is more preferably 3 to 50 μm, and particularly preferably 5 to 20 μm.

The average particle diameter D50 of the dendrite-shaped particles is preferably 2 to 100 μm, more preferably 2 to 80 μm. The thickness is more preferably 3 to 50 μm, and particularly preferably 5 to 20 μm. By using the scale-like particles and the dendrite-like particles together, the surface glossiness can be optimized and the print visibility can be improved when the characters are directly printed on the electromagnetic wave shield layer.

The average particle diameter D50 can be measured by a laser diffraction/scattering method. Specifically, for example, it is a numerical value obtained by measuring each conductive fine particle with a tornado dry powder sample module using a laser diffraction/scattering particle size distribution analyzer LS 13320 (manufactured by Beckman Coulter, Inc.). , The average particle diameter of the diameter of the particle diameter for which the integrated value of the particles is 50%. The refractive index is set to 1.6 for measurement. The average particle diameter D50 of each particle in the electromagnetic wave shield member 1 can be obtained by measuring the particle diameter of 100 particles using a scanning electron microscope (SEM) and determining the frequency distribution. In the case of needle-shaped particles and dendrite-shaped particles, the longest length of each particle is used as the particle size.

The composition forming the conductive adhesive layer may further contain a colorant, a flame retardant, an inorganic additive, a lubricant, an antiblocking agent and the like.
Examples of the colorant include organic pigments, carbon black, ultramarine blue, red iron oxide, zinc white, titanium oxide, graphite and the like. Among these, the inclusion of the black colorant improves the print visibility of the shield layer.
Examples of the flame retardant include halogen-containing flame retardants, phosphorus-containing flame retardants, nitrogen-containing flame retardants, inorganic flame retardants, and the like.
Examples of the inorganic additive include glass fiber, silica, talc, ceramics and the like.
Examples of the lubricant include fatty acid ester, hydrocarbon resin, paraffin, higher fatty acid, fatty acid amide, aliphatic alcohol, metal soap, modified silicone and the like.
Examples of antiblocking agents include calcium carbonate, silica, polymethylsilsesquiosan, and aluminum silicate salts.

The conductive adhesive layer may be any layer as long as it has conductivity due to continuous contact of the conductive filler by thermocompression bonding, and does not necessarily have conductivity at the stage before thermocompression bonding. The conductive adhesive layer can be formed by mixing and stirring the above-described conductive filler and a composition containing a binder resin precursor, coating the composition on a releasable substrate, and then drying. Alternatively, the releasable cushion member 3 may be directly applied and dried.

After applying the coating liquid for the conductive adhesive layer, it is dried to form the conductive adhesive layer on the releasable substrate. It is preferable to perform heating (for example, 80 to 120° C.) in the drying step. From the viewpoint of adjusting the kurtosis of the electromagnetic wave shield member, it is preferable to perform drying at 25° C. (room temperature) and normal pressure for 1 to 10 minutes after applying the coating liquid and before heating and drying. More preferable drying time at 25° C. (room temperature) before heat drying is 2 to 6 minutes. The kurtosis value can be adjusted by providing a process of drying at room temperature before heat drying.

The influence of the viscosity of the coating liquid and the drying time at 25° C. before heating and drying on the kurtosis of the electromagnetic wave shield member 1 will be described with reference to the schematic diagram of FIG. 9. As shown in the figure, a coating liquid is applied on the releasable substrate 15 to form the conductive adhesive layer 6. A conductive adhesive layer 6P that is in the process of drying and contains a solvent is obtained.

By setting a longer drying time at 25° C. for the conductive adhesive layer 6P in the process of heating, as shown in FIG. 9, the state in which the evaporation rate of the solvent is slow is intentionally lengthened, thereby making the binder resin The subduction of the precursor 10 can be promoted. On the other hand, by setting the drying time at 25° C. short, the sinking of the binder resin precursor 10 to the lower side is suppressed as shown in FIG. 9, and the conductive filler 11 easily rises by heating and drying at that stage. Become. Moreover, foaming easily occurs due to evaporation of the solvent, and the surface tends to be rough.

The solid content of the coating liquid is preferably 20 to 50% in order to set the kurtosis value of the electromagnetic wave shield member 1 to 1 to 8. Further, in order to adjust the kurtosis of the electromagnetic wave shield member, it is preferable that the coating liquid viscosity of the coating liquid measured with a B-type viscometer is in the range of 200 to 5000 mPa·s. Further, in order to adjust the kurtosis of the electromagnetic wave shield member, it is preferable that the thixotropy index of the coating liquid is 1.2 to 2.0. In addition, the conductive filler 11 of FIG. 9 and FIG. 10 described later is a scaly particle, and the figure is not a plan view of the main surface but a sectional view of a section in the thickness direction.

The value of kurtosis also changes depending on the viscosity of the coating liquid for forming the conductive adhesive layer. The higher the viscosity of the coating liquid, the more the fluidity of the conductive filler tends to be suppressed. Therefore, when the viscosity is high, the conductive fillers 11 tend not to be oriented and become random. On the other hand, when the viscosity is low, the scale-like particles tend to be oriented so that the main surface thereof faces the substrate surface. Further, when the drying time at 25° C. is shortened to perform heat drying, when the viscosity is high, the surface roughness due to foaming tends to increase, and when the viscosity is low, the conductive filler tends to move in the vertical direction. ..
In this way, the kurtosis can be adjusted by adjusting the viscosity of the coating liquid and the drying time at 25°C.

The kurtosis of the electromagnetic wave shield member 1 can also be adjusted by the particle diameter of the dendrite-shaped particles and/or the acicular particles. The effect of the particle size of the dendrite-shaped particles and/or the acicular particles on the kurtosis of the electromagnetic wave shield member 1 will be described with reference to the schematic explanatory view of FIG. 10. Similar to FIG. 9, by applying a coating liquid to form the conductive adhesive layer 6 on the releasable base material 15, the conductive adhesive layer 6P in the process of being dried can be obtained. 10, components and members common to those in FIG. 9 are designated by the same reference numerals. As shown in FIG. 10, when the average particle diameter D50 of the dendrite-like particles 12 which is a kind of conductive filler is small, the value of the kurtosis tends to decrease, and conversely, the average particle diameter D50 of the dendrite-like particles 12 is large. And the value of Kurtosis tends to increase. Depending on the thickness of the conductive adhesive layer 6, when it is desired to reduce the value of kurtosis, for example, the average particle diameter D50 is 2 to 5 μm, and when the value of kurtosis is desired to be increased, the average particle diameter D50 is, for example, 20 to When it is desired to set 50 μm, or an intermediate value between them, the average particle diameter D50 can be set to more than 5 μm and less than 20 μm.

In addition, in order to adjust the kurtosis of the electromagnetic wave shield member 1, after coating and drying the conductive adhesive composition for forming the conductive adhesive layer 6 which is the outermost layer of the electromagnetic wave shield member 2, the corona is applied. It is preferable to perform treatment or plasma treatment. Corona treatment is preferably irradiated amount of corona discharge electron is 1~1,000W / m ² / min, and more preferably in the 10~100W / m ² / min.

The kurtosis of the electromagnetic wave shield member 1 can be adjusted by increasing the amount of needle-like or dendrite-like conductive filler added to the composition forming the electromagnetic wave shield member 2 before thermocompression bonding. The kurtosis of the electromagnetic wave shield member 1 can also be adjusted by the average particle diameters D50 and D90 of the conductive filler.

The releasable substrate is a substrate having releasability on one side or both sides, and is a sheet having a tensile breaking strain at 150° C. of less than 50%. Examples of the releasable base material include polyethylene terephthalate, polyethylene naphthalate, polyvinyl fluoride, polyvinylidene fluoride, rigid polyvinyl chloride, polyvinylidene chloride, nylon, polyimide, polystyrene, polyvinyl alcohol, ethylene/vinyl alcohol copolymer, and polycarbonate. , Polyacrylonitrile, polybutene, soft polyvinyl chloride, polyvinylidene fluoride, polyethylene, polypropylene, polyurethane resin, ethylene vinyl acetate copolymer, plastic sheets such as polyvinyl acetate, glassine paper, fine paper, kraft paper, coated paper, etc. Papers, various non-woven fabrics, synthetic papers, metal foils, and composite films combining these.

(Releasable cushion member)
The releasable cushion member 3 is a sheet that functions as a cushioning material that promotes followability of the conductive adhesive layer 6 to the electronic component 30 and that has releasability. That is, it is a layer that can be separated from the electromagnetic wave shield member 1 after the thermocompression bonding process. Further, it is preferable that the layer has a tensile breaking strain at 150° C. of 50% or more and melts during thermocompression bonding.

The tensile breaking strain of the releasable base material and the releasable cushion member is a value obtained by the following method. The releasable base material and the releasable cushion member were cut into a size of width 200 mm×length 600 mm to obtain a measurement sample. A tensile test (test speed 50 mm/min) was carried out on the measurement sample using a small bench tester EZ-TEST (manufactured by Shimadzu Corporation) under the conditions of a temperature of 25° C. and a relative humidity of 50%. The tensile breaking strain (%) was calculated from the obtained SS curve (Stress-Strain curve).

As the releasable cushion member, polyethylene, polypropylene, polyether sulfone, polyphenylene sulfide, polystyrene, polymethylpentene, polybutylene terephthalate, cyclic olefin polymer and silicone are preferable. Of these, polypropylene, polymethylpentene, polybutylene terephthalate, and silicone are more preferable from the viewpoint of achieving both embedding properties and releasability. The releasable cushion member may be used in a single layer or multiple layers. In the case of multiple layers, sheets of the same type or different types can be laminated.

The method of laminating the releasable cushion member 3 and the conductive adhesive layer 6 is not particularly limited, but a method of laminating these sheets can be mentioned. Since the releasable cushion member 3 is finally peeled off, a material having excellent releasability is preferable. The thickness of the releasable cushion member is, for example, about 50 μm to 3 mm, more preferably about 100 μm to 1 mm.

[Second Embodiment]
Next, an example of an electronic component mounting board different from that of the first embodiment will be described. The electronic component mounting board according to the second embodiment is different from the first embodiment using the electromagnetic wave shield member including a single electromagnetic wave shield layer in that the electromagnetic wave shield member includes two electromagnetic wave shield layers. However, other basic configurations and manufacturing methods are the same. Note that descriptions that overlap with those of the first embodiment are omitted as appropriate.

The electromagnetic wave shield member of the second embodiment is, as shown in FIG. 11, an electromagnetic wave shield that is a conductive adhesive layer 6a composed of two layers of a first conductive adhesive layer 6a1 and a second conductive adhesive layer 6a2. It is formed using the member 2a and the electromagnetic wave shielding laminate 4a including the releasable cushion member 3a. By thermocompression-bonding the electromagnetic wave shielding laminate 4a, the electromagnetic wave shielding member including the first electromagnetic wave shielding layer and the second electromagnetic wave shielding layer is coated on the substrate 20 on which the electronic component 30 is mounted. In the electromagnetic wave shield member that is a laminate of the two electromagnetic wave shield layers, the indentation elastic modulus measured from the surface layer side is 1 to 10 GPa. By comprising two electromagnetic wave shield layers, the degree of freedom in designing the electromagnetic wave shield member can be increased. For example, a mode in which a laminate of an electromagnetic wave reflection layer and an electromagnetic wave absorption layer is used can be exemplified. You may laminate|stack three or more electromagnetic wave shield layers.

According to the electronic component mounting board of the second embodiment, the same effect as that of the first embodiment can be obtained by using the electromagnetic wave shield member including the two electromagnetic wave shield layers. Further, by laminating two electromagnetic wave shield layers, the degree of freedom in designing each layer can be increased, which is advantageous in that it is easy to provide an electromagnetic wave shield member according to needs.

[Third Embodiment]
The electronic component mounting board according to the third embodiment is different from the first embodiment in which the electromagnetic wave shield member is composed of a single electromagnetic wave shield layer in that the electromagnetic wave shield member is a laminate of an electromagnetic wave shield layer and a hard coat layer. Although different, the other basic structure and manufacturing method are the same.

The electromagnetic wave shielding member according to the third embodiment is, as shown in FIG. 12, an electromagnetic wave shielding member 2b and a releasable cushion member 3b which are a laminated body of one conductive adhesive layer 6b and an insulating resin layer 7b. It is formed by using the electromagnetic wave shielding laminate 4b. By thermocompression-bonding this electromagnetic wave shield laminate 4b, a hard coat layer formed of an electromagnetic wave shield layer formed of a conductive adhesive layer 6b and an insulating resin layer 7b is formed on a substrate on which electronic components are mounted. An electromagnetic wave shield member composed of The electromagnetic wave shield member according to the third embodiment has an indentation elastic modulus of 1 to 10 GPa when measured from the hard coat layer side.

The insulating resin layer 7b is a layer formed from a resin composition containing a binder resin precursor and an inorganic filler. The binder resin precursor contains at least a thermosoftening resin. Examples and preferred examples of the binder resin precursor are the same as those of the conductive adhesive layer of the electromagnetic wave shielding member described in the first embodiment. The binder resin precursors of the conductive adhesive layer and the insulating resin layer may be the same or different.

The inorganic filler does not have conductivity unlike the conductive adhesive layer of the first embodiment, but the characteristics of the preferable inorganic filler, for example, the shape, blending amount, D50, D90, etc., are the same as those of the conductive filler. Is the same. Examples of the inorganic filler include silica, alumina, magnesium hydroxide, barium sulfate, calcium carbonate, titanium oxide, zinc oxide, antimony trioxide, magnesium oxide, talc, kaolinite, mica, basic magnesium carbonate, sericite, montmoroli. Inorganic compounds such as knight, kaolinite and bentonite can be mentioned.

Suitable examples of the preferable blending component and the blending amount of the binder resin precursor used for the insulating resin layer are the same as those of the conductive adhesive layer of the first embodiment. Further, the preferable shape of the inorganic filler used for the insulating resin layer, the preferable average particle diameter D50 and the like are the same as those of the conductive filler of the first embodiment.

The heat-softenable resin composition, and the heat-softenable resin composition layer, if necessary, a colorant, a silane coupling agent, an ion scavenger, an antioxidant, a tackifying resin, a plasticizer, an ultraviolet absorber, a leveling agent. Modifiers, flame retardants and the like can be included.

According to the electronic component mounting board of the third embodiment, by using the electromagnetic wave shielding member having the hard coat layer, in addition to the effect described in the first embodiment, the electromagnetic wave shielding layer is covered with the hard coat layer. It is possible to provide an electromagnetic wave shield member having more excellent durability.

[Fourth Embodiment]
The electronic component mounting board according to the fourth embodiment is the same as the first embodiment using the electromagnetic wave shield member including a single electromagnetic wave shield layer in that the electromagnetic wave shield member is a laminate of an electromagnetic wave shield layer and an insulating coating layer. Although different, the other basic configuration and manufacturing method are the same as those in the first embodiment.

As shown in FIG. 13, the electromagnetic wave shield member according to the fourth embodiment includes an electromagnetic wave shield member 2c, which is a laminate of an insulating adhesive layer 8c and a conductive adhesive layer 6c, and a releasable cushion member 3c. It is formed using the electromagnetic wave shielding laminate 4c.

In the fourth embodiment, an example will be described in which the electromagnetic wave shield member is coated on a substrate on which a plurality of electronic components (for example, semiconductor packages) on which the individualizing step has not been performed or which have been individualized have been formed. As shown in FIG. 14( a ), the electromagnetic wave shielding laminate 4 c is arranged above the substrate 20 on which the electronic component 30 having the solder balls 24 functioning as connection terminals with the substrate 20 is mounted, and the releasability is improved. Thermocompression bonding is performed from the cushion member 3c side to the substrate 20 on which the electronic component 30 is mounted (FIG. 14B). Then, the releasable cushion member 3c is peeled off to obtain the electronic component mounting substrate 53 in which the electromagnetic wave shield member 1c of FIG. 14(c) is laminated. The electromagnetic wave shield member 1c according to the fourth embodiment has an indentation elastic modulus of 1 to 10 GPa when measured from the electromagnetic wave shield layer 5c side.

The obtained electronic component mounting substrate 53 can take GND from the upper surface of the electromagnetic wave shield layer 5c. In place of this method, a ground pattern is provided on the substrate 20, and in order to make the ground pattern and the electromagnetic wave shield layer 5c electrically conductive, the conductive pattern is penetrated through the insulating coating layer 9c on the ground pattern and electrically connected to the electromagnetic wave shield layer 5c. The connector part may be provided.

In the fourth embodiment, an example of a method of manufacturing an electronic component mounting board that does not require an individualizing step has been described. However, on the mother board, the unit of the product unit of FIG. It is also possible to obtain the electronic component mounting substrate shown in FIG. 14C by placing the shield laminate 4c and thermocompressing it to form an electromagnetic wave shield layer, and then performing an individualizing step.

The insulating adhesive layer 8c is a layer formed from a resin composition containing a binder resin precursor. The binder resin precursor contains at least a thermosoftening resin. Examples and preferred examples of the binder resin precursor include the binder resin precursor of the conductive adhesive layer described in the first embodiment. The binder resin precursors of the insulating adhesive layer 8c and the conductive adhesive layer 6c may be the same or different.

The heat-softenable resin composition and the heat-softenable resin composition layer are, if necessary, a colorant, a silane coupling agent, an ion scavenger, an antioxidant, a tackifier resin, a plasticizer, an ultraviolet absorber, and a leveling adjustment. Agents, flame retardants, inorganic fillers, etc. may be included.

According to the electronic component mounting board according to the fourth embodiment, by using the electromagnetic wave shield member 1c having the insulating coating layer 9c, in addition to the effect described in the first embodiment, a circuit other than the ground pattern, an electrode pattern, or the like can be obtained. It is possible to prevent a short circuit between the conductor portion and the electromagnetic wave shield member, and enhance the joint reliability between the electronic component and the electromagnetic wave shield layer. Also, the insulation reliability of the electronic component can be improved. Therefore, the electromagnetic wave shield member having excellent durability can be provided. As a result, it is possible to provide an electronic component mounting board having excellent electromagnetic wave shielding properties. Further, since the shield layer can be formed all over the substrate at once, the manufacturing process is simple and the thickness can be remarkably reduced as compared with a shield can or the like.

In the fourth embodiment, the insulating coating layer 9c is mainly used for strengthening the bonding between the electronic component and the electromagnetic wave shield member, but the insulating coating layer 9c can be applied to a sealing material. When the insulating coating layer 9c is applied to the sealing material, there is an advantage that the step of sealing the semiconductor chip and the like and the coating of the electromagnetic wave shield member can be performed in the same step. That is, the electromagnetic wave shield member according to the fourth embodiment is applied to an electronic component which is an insulator and is not integrally covered, and an insulating coating corresponding to the sealing material (mold resin) from the insulating adhesive layer. You can also get layers. In this case, in order to cover the electromagnetic wave shielding member on the side surface of the electronic component, a press plate in which concave portions corresponding to the electronic component are formed in an array (a press plate having a convex portion for embedding the electromagnetic wave shielding member in a gap between the electronic components is formed). A plate) may be used.

[Fifth Embodiment]
In the electronic component mounting board according to the fifth embodiment, the electromagnetic wave shield layer and the ground pattern are in direct contact with each other for electrical conduction, and the conductive adhesive layer located in the inner layer of the electromagnetic wave shield laminate is the same as that of the laminate body. An electromagnetic wave shielding laminate having an exposed region at a stage is used. The exposed region is provided so that a conductive pattern such as a ground pattern formed on the substrate or the like and the electromagnetic wave shield layer come into contact with each other to establish electrical conduction. The fifth embodiment is different from the fourth embodiment in these points, but the other basic configuration and manufacturing method are the same.

The electromagnetic wave shielding laminate according to the fifth embodiment has the same laminated structure as that of the fourth embodiment, but as shown in FIG. 15A, a region that covers the ground pattern 22 formed on the substrate 20. The conductive adhesive layer 6d is exposed in the electromagnetic wave shielding laminate 4d at a position corresponding to. Specifically, the exposed region of the conductive adhesive layer 6d is provided in a top view from the insulating adhesive layer 8d side. In the example of the electromagnetic wave shielding laminate 4d of FIG. 15(a), the size of the insulating adhesive layer 8d is made one size smaller than the size of the electromagnetic wave shielding laminate 4d, so that the frame region of the electromagnetic wave shielding laminate 4d is reduced. The conductive adhesive layer 6d is exposed. With such a configuration, as shown in FIGS. 15B and 15C, the electronic component mounting substrate 54 in which the ground pattern 22 and the electromagnetic wave shield layer 5d are brought into contact with each other by thermocompression to be conductive is obtained. The position of the exposed portion of the conductive adhesive layer 6d in the electromagnetic wave shielding laminate 4d is not limited to the example of FIG. 15A, and the exposed portion may be formed as an opening pattern.

<Modification>
Next, modifications of the electronic component mounting board and the like according to the present embodiment will be described. However, the present invention is not limited to the above-described embodiments and modifications, and other embodiments may be included in the scope of the present invention as long as they match the gist of the present invention. Further, the respective embodiments and modified examples are preferably combined with each other.

In the fourth and fifth embodiments, an example in which an electromagnetic wave shield laminate including a laminate of an insulating adhesive layer, a conductive adhesive layer, and a releasable cushion member is used has been described. It is also possible to do so. That is, as shown in FIG. 16A, the insulating coating layer 9e is first formed on the substrate 20 on which the plurality of electronic components 30 are mounted, as shown in FIG. 16B. The insulating coating layer 9e is obtained by hot pressing a sheet containing an insulating adhesive layer. Then, the electromagnetic wave shield layer 5e is formed by using the electromagnetic wave shield laminate 4e, which is a laminate of the conductive adhesive layer 6e and the releasable cushion member 3e (FIGS. 16C and 16D). Through these steps, the electronic component mounting board 55 on which the electromagnetic wave shield member is formed is obtained. The insulating coating layer 9e can be exemplified by a method of applying a solution resin and a method of spraying a solution resin, instead of the method of hot pressing the sheet.

In the above embodiment, an electronic component has been described as an example of the component, but the present invention can be applied to all components desired to be shielded from electromagnetic waves. The shape of the component is not limited to a rectangular shape, and includes a component having an R-shaped corner, a component having an acute angle between the upper surface and the side surface of the component, and a component having an obtuse angle. It also includes a case where the top surface is uneven, and the case where the outer surface of the electronic part is a curved surface such as a sphere. Further, in the above-described embodiment, the half dicing groove 25 (see FIG. 2) is formed on the substrate 20, but the half dicing groove 25 is not essential, and the electromagnetic wave shield member may be placed and covered on a flat substrate. Good. In addition, the electronic component mounting board of the present invention includes a case where the component mounting board on which the electronic component obtained by, for example, all-dicing the substrate 20 is mounted is mounted on another holding base material or the like. ..

Further, the electromagnetic wave shield laminate is not limited to the laminate form of the above embodiment. For example, a support substrate may be laminated on the releasable cushion member. By stacking the support substrates, it is possible to easily prevent the device from being soiled during thermocompression bonding. In addition, the support substrate has an advantage that the step of attaching the electromagnetic wave shielding laminate is facilitated. Further, the electronic components can be mounted not only on one side of the substrate but also on both sides, and the electromagnetic wave shield member can be formed on each electronic component.

The electronic component mounting board according to the present embodiment is excellent in covering property with respect to the concavo-convex structure, and thus can be suitably applied to various electronic devices such as personal computers, mobile devices, and digital cameras.

<<Example>>
Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. In addition, "part" in the examples means "part by mass", and "%" means "% by mass". The values described in the present invention were determined by the following method. In addition, in order to make it consistent with the invention according to claim 1, Examples 1 to 3, 5, and 6 described later are to be read as Reference Examples 1, 3, 5, and 6, respectively.

(Preparation of test board)
A substrate was prepared in which 5×5 array of mold-sealed electronic components (1 cm×1 cm) were mounted on the substrate made of glass epoxy. The thickness of the substrate is 0.3 mm, and the mold sealing thickness, that is, the height (component height) H from the upper surface of the substrate to the top surface of the mold sealing material is 0.7 mm. After that, half dicing was performed along the groove that is a gap between the components to obtain a test board (see FIG. 17). The half cut groove depth was 0.8 mm (the cut groove depth of the substrate 20 was 0.1 mm), and the half cut groove width was 200 μm.

The materials used in the examples are shown below.
・Binder resin precursor Resin 1: Urethane resin,
Resin 2: Polycarbonate resin,
Resin 3: Styrene elastomer resin,
Resin 4: Phenoxy resin,
Curable compound 1: Deconal EX830
Curable compound 2: jERYX8000,
Curable compound 3: jER157S70,
-Curing accelerator: PZ-33
Conductive filler Conductive filler 1: Flake Ag (average particle diameter D50: 11 μm)
Conductive filler 2: acicular silver-coated copper (average particle diameter D50: 7.5 μm)
・Additive Additive 1: BYK322,
Additive 2: BYK337

[Example 1]
(Preparation of Resin Composition of Conductive Adhesive Layer)
As shown in Table 1, 70 parts (solid content) of resin 1 (urethane resin), 30 parts (solid content) of resin 2 (polycarbonate resin), and curable compound 1 (epoxy resin) as binder resin precursors 30 parts, 15 parts of curable compound 2 (epoxy resin), 280 parts of conductive filler 1 (flake-like Ag), 50 parts of conductive filler 2 (acicular Ag coat Cu), and curing acceleration. 1 part of the agent and 0.4 part of the additive 1 were charged into a container, a mixed solvent of toluene:isopropyl alcohol (mass ratio 2:1) was added so that the nonvolatile content concentration was 35% by mass, and the mixture was mixed with a disper for 10 minutes. A resin composition for forming a conductive adhesive layer was obtained by stirring.

(Preparation of laminate for electromagnetic wave shield)
This resin composition was applied to a releasable substrate using a doctor blade so that the dry thickness would be 50 μm. Then, after being dried at 25° C. for 12 minutes at room temperature, it was dried at 100° C. for 2 minutes to obtain an electromagnetic wave shielding member (conductive adhesive layer). After that, a releasable cushion member CR1020, a layer structure (thickness 150 μm) in which both surfaces of the soft resin layer are sandwiched by polymethylpentene, manufactured by Mitsui Chemicals Tohcello Co., Ltd. are prepared and laminated with an electromagnetic wave shielding member to provide releasability. An electromagnetic wave shielding laminate according to Example 1 was obtained on the base material.

(Preparation of test pieces for electronic component mounting boards)
Next, the laminate for electromagnetic wave shielding on the releasable substrate was cut into 10×10 cm, the releasable substrate was peeled off, and then the laminate for electromagnetic wave shielding was placed on the test substrate (see FIG. 17). It was placed and temporarily attached so that the conductive adhesive layer surface side of the body was in contact. Then, thermocompression bonding was performed on the substrate surface from above the electromagnetic wave shielding laminate at 2 MPa and 180° C. for 2 hours. After the thermocompression bonding, the releasable cushion member was peeled off to obtain an electronic component mounting substrate (test piece) according to Example 1 covered with the electromagnetic wave shield member.

[Examples 2 to 19, Comparative Examples 1 and 2]
In the same manner as in Example 1 except that the compositions shown in Tables 1 and 2 were changed, the resin composition of the conductive adhesive layer of each Example and Comparative Example, the electromagnetic wave shielding laminate, and the electronic component mounting substrate. The test piece of was obtained.

<Indentation elastic modulus>
The electromagnetic wave shield laminates of Examples 1 to 19 and Comparative Examples 1 and 2 were prepared, placed on a FR4 substrate having a thickness of 300 μm, and 180° C. for 2 hours under the condition of 2 MPa in the surface direction from the releasable cushion member side. Heating was performed. Then, the releasable cushion member was peeled off to obtain a test piece of FR4 substrate on which the electromagnetic wave shield member was formed. Then, the indentation elastic modulus was measured from the side where the releasable cushion member was laminated by the following method.
That is, using a Fischer Scope H100C (manufactured by Fischer Instruments Co., Ltd.) type hardness meter, using a Vickers indenter (diamond indenter with a 100φ tip having a spherical tip), a test force of 0.3N and a test force at 25° C. The holding time was 20 seconds, and the test force addition time was 5 seconds. The indentation elastic modulus was determined by averaging the values obtained by repeatedly measuring the same film surface of the electromagnetic wave shield member at five locations.

In the measurement of the indentation elastic modulus of the electromagnetic wave shield member, the electromagnetic wave shield member actually coated on the electronic component mounting board can be measured. In this case, the Vickers indenter is brought into direct contact with the electromagnetic wave shield member coated on the electronic component substrate for measurement. Also with respect to the kurtosis and the water contact angle, which will be described later, the electromagnetic wave shield member actually coated on the electronic component mounting board can be measured in the same manner.

<Kurtosis>
The electromagnetic wave shielding laminates of Examples and Comparative Examples were prepared, placed on a FR4 substrate having a thickness of 300 μm, and heated and pressed at 170° C. for 5 minutes under the condition of 8 MPa in the surface direction from the releasable cushion member side. Thereafter, the releasable cushion member was peeled off, and heating was performed at 180° C. for 2 hours. Then, the releasable cushion member was peeled off to obtain a test piece of FR4 substrate on which the electromagnetic wave shield member was formed. In this test piece, the surface of the electromagnetic wave shield member from which the releasable cushion member was peeled off was subjected to metal sputtering treatment. The conditions for the metal sputtering treatment were that a sputtering device “Smart Coater” manufactured by JEOL Ltd. was used, gold was used as a target, and the separation distance between the target and the sample surface was 2 cm, and sputtering was performed for 0.5 minutes. For the metal sputtered surface of the obtained sample, the kurtosis was determined using a laser microscope (VK-X100, manufactured by Keyence Corp.) according to JIS B 0601:2001. The measurement conditions were such that the measurement magnification was 1000 times in the shape measurement mode and the surface shape was acquired. The obtained surface shape image was subjected to surface roughness measurement of an analysis application, and the entire area was selected, and the λs contour curve filter was set to 2.5 μm and the λc contour curve filter was set to 0.8 mm, and kurtosis was measured. The above measurement was carried out at five different points, and the average value of the measured values was used as the kurtosis value.
In the measurement of the kurtosis of the electromagnetic wave shield member, when measuring the electromagnetic wave shield member actually coated on the electronic component mounting substrate, the electromagnetic wave shield member coated on the electronic component substrate may be directly measured. ..

<Water contact angle>
For the test piece of FR4 substrate prepared in the same way as the sample for measuring the indentation elastic modulus, "Automatic contact angle meter DM-501/Analysis software FAMAS" manufactured by Kyowa Interface Science Co., Ltd. was used for the surface of the electromagnetic wave shield layer. Then, the water contact angle of the electromagnetic wave shield member was measured. The measurement was performed by a liquid method.

<Measurement of Martens hardness>
The test pieces of the electronic component mounting boards of the respective examples and comparative examples were prepared, and the Martens hardness was measured by a Fischer Scope H100C (manufactured by Fischer Instruments Co., Ltd.) type hardness meter in accordance with ISO14577-1. For the measurement, a Vickers indenter (diamond indenter with a 100φ tip having a spherical tip) is used on the upper surface of the electronic component 30, and a test force of 0.3 N, a test force holding time of 20 seconds, and a test in a thermostatic chamber at 25° C. It was carried out under the condition that the time required to apply force was 5 seconds. The average value of the values obtained by repeatedly measuring 10 times the same cured film surface at random was defined as Martens hardness. The test force is adjusted according to the thickness of the electromagnetic wave shield layer. Specifically, the test force was adjusted so that the maximum indentation depth was about 1/10 of the thickness of the electromagnetic wave shield member.

<Viscosity of coating liquid and thixotropic index>
The obtained conductive resin composition was allowed to stand in a water bath at 25° C. for 30 minutes, and then, with a “B type viscometer” (manufactured by Toki Sangyo Co., Ltd.), a viscosity (v1) at a rotation speed of 6 rpm and a rotation speed of 60 rpm. The viscosity (v2) of was measured. The value obtained by dividing (v1) by (v2) was used as a thixotropic index.

<Burr during full dicing>
The electromagnetic wave shielding laminates of Examples and Comparative Examples were thermocompression-bonded to the above-mentioned test substrate (a substrate on which electronic components were mounted in an array of 5×5 pieces) under conditions of 8 MPa and 170° C. for 5 minutes, and releasability was improved. The cushion member was peeled off by hand. Then, it was cured at 180° C. for 2 hours to obtain a test sample coated with the electromagnetic wave shield member. With respect to the obtained test sample, the occurrence state of burrs when an individualizing step (full dicing) was performed was evaluated by the following criteria using a laser microscope.
+++: No burr is confirmed.
++: Less than 2 out of 25 electronic components in which burrs are generated.
+: 2 or more and less than 5 out of 25 electronic components in which burrs are generated.
NG: 5 or more out of 25 electronic components in which burrs are singulated.

<Tape adhesion>
On the FR4 substrate having a thickness of 300 μm, the electromagnetic wave shielding laminates of Examples and Comparative Examples cut into 5×5 cm were placed, respectively, and hot pressed at 170° C. for 8 minutes under the condition of 8 MPa, and then at 180° C. for 2 hours. A test substrate was obtained by curing. Then, the releasable cushion member was peeled off. Then, the obtained test substrate was subjected to a pressure cooker test at 130° C., a humidity of 85%, and a pressure of 0.23 MPa. The test time was 96 hours, and an Nichiban adhesive tape having a width of 18 mm was used as the adhesive tape. Then, using a cross-cut guide according to JIS K5600, 25 grids having an interval of 1 mm were produced on the electromagnetic wave shield member. After that, an adhesive tape was pressure-bonded to the cross-cut portion of the electromagnetic wave shield member, the end of the tape was peeled off at an angle of 45°, and a tape adhesion test was conducted. The cross-cut state (crosscut residual rate) of the electromagnetic wave shield member was judged according to the following criteria.
+++: Shows the residual rate of 25/25.
++: Shows the residual rate of 24/25.
+: The residual rate of 23/25 is shown.
NG: less than 23/25 residual rate.

<Peelability evaluation of the half dicing groove of the releasable cushion member after thermocompression bonding>
The electromagnetic wave shielding laminates of Examples and Comparative Examples were thermocompression bonded to the test substrate (half dicing groove depth 800 μm, groove width 200 μm) under conditions of 8 MPa and 170° C. for 5 minutes to form a releasable cushion. The member was peeled off by hand. Then, the number of releasable cushion members torn and left in the groove in the gap between the electronic components was visually confirmed. The evaluation criteria are as follows.
+++: No residue is observed.
++: 1 or more residue and less than 3 residue.
+: 3 or more residues and less than 5 residues.
NG: 5 or more residues, or the residue remains in the entire groove.

<Steel wool resistance>
The electromagnetic wave shielding laminates of Examples and Comparative Examples cut into 5×15 cm were placed on a 125 μm-thick polyimide film (“Kapton 500H” manufactured by Toray-Dupont Co., Ltd.), respectively, and the conditions were 180° C. and 2 MPa. After hot pressing for 10 minutes, a test substrate was obtained by curing at 180° C. for 2 hours. Then, the releasable cushion member was peeled off. Then, the electromagnetic wave shield member was set on a Gakushin abrasion tester (manufactured by Tester Sangyo Co., Ltd.), and the electromagnetic wave shield member was abraded and the polyimide film was formed under the conditions of a load of 200 gf, a stroke of 120 mm, and a reciprocating speed of 30 times/min. The number of academic achievements until exposure was calculated. The evaluation criteria are as follows.
+++: 20,000 times or more.
++: 10,000 times or more and less than 20,000 times.
+: 5,000 times or more and less than 10,000 times (practical level).
NG: less than 5,000 times.

Tables 1 and 2 show the evaluation results of Examples 1 to 19 and Comparative Examples 1 and 2.

As shown in the examples of Table 1 and Table 2, the electronic component mounting board using the electromagnetic wave shielding member of Comparative Example 1 having the indentation elastic modulus of less than 1 did not reach the pass level in the burr at the time of full dicing. On the other hand, all the electromagnetic wave shielding members of the electronic component mounting board of the present invention have reached the pass level, and it has been confirmed that the occurrence of burrs can be suppressed. In addition, the electronic component mounting board using the electromagnetic wave shield member of Comparative Example 2 having the indentation elastic modulus of more than 10, the tape adhesion after the PCT test did not reach the pass level. On the other hand, it was confirmed that all the electromagnetic wave shielding members of the electronic component mounting board of the present invention had a tape adhesion level after the PCT test at an acceptable level and excellent PCT resistance.

FIG. 18 shows an image obtained by observing the side surface of the electronic component mounting substrate after being diced in Example 3 with a microscope. As shown in the figure, no burr was observed. On the other hand, FIG. 19 shows an image obtained by observing the side surface of the electronic component mounting substrate of Comparative Example 1 after singulation with a microscope. As shown in the figure, the occurrence of burrs was observed.

[Note]
The present specification also discloses inventions of the following technical ideas that are grasped from the above-described embodiments.
(Appendix 1)
An electromagnetic wave shielding member having a conductive adhesive layer containing a binder resin precursor and a conductive filler,
Having a releasable cushion member laminated on the electromagnetic wave shielding member,
When the electromagnetic wave shield member is obtained by peeling the releasable cushion member after heating at 180° C. for 2 hours under the condition of 2 MPa in the surface direction from the releasable cushion member side, the releasable cushion member The laminated body for electromagnetic wave shielding, wherein the indentation elastic modulus of the electromagnetic wave shielding member is in the range of 1 to 10 GPa when measured from the side where was laminated.
(Appendix 2)
When the electromagnetic wave shielding member is obtained by peeling the releasable cushion member after heating at 180° C. for 2 hours in the surface direction from the releasable cushion member side at 2 MPa, the releasability is 2. The electromagnetic wave shield laminate according to appendix 1, wherein the surface layer on the side where the cushion member is laminated has a water contact angle of 70 to 100°.
(Appendix 3)
When the electromagnetic wave shielding member is obtained by peeling the releasable cushion member after heating at 180° C. for 2 hours under the condition of 2 MPa in the surface direction from the releasable cushion member side, the releasable cushion The laminate for electromagnetic wave shielding according to Supplementary Note 1 or Supplementary Note 2, which has a kurtosis of 1 to 8 when measured according to JIS B0601; 2001 from the side where the members are laminated.

1 Electromagnetic Wave Shielding Member 2 Electromagnetic Wave Shielding Member 3 Releasable Cushion Member 4 Electromagnetic Wave Shielding Laminate 5 Electromagnetic Wave Shielding Layer 6 Conductive Adhesive Layer 6P Conductive Adhesive Layer 7b Insulating Resin Layer 8c Insulating Adhesive Layer 9c Insulating coating layer 10 Binder resin precursor 11 Conductive filler
12 dendrite particles 15 releasable substrate 20 substrate 21 electrode 22 ground pattern 23 inner via 24 solder ball 25 half dicing groove 30 electronic component 31 semiconductor chip 32 mold resin 33 bonding wire 40 press substrate 51, 52 electronic component mounting substrate

Claims (8)

Board,
An electronic component mounted on at least one surface of the substrate,
An electromagnetic wave shield member that covers from the upper surface of the electronic component to the substrate, covers the side surface of the step formed by mounting the electronic component and at least a part of the substrate,
The electromagnetic wave shield member has an electromagnetic wave shield layer containing a binder resin and a conductive filler, and has an indentation elastic modulus of 1 to 10 GPa and a Martens hardness of 114 to 312 N/mm ² . The electronic component mounting board according to claim 1, wherein a water contact angle of a surface layer of the electromagnetic wave shield member is 70 to 110°. The electronic component according to claim 1 or 2, wherein the electromagnetic shield member on the electronic component exhibits a crosscut residual ratio of 23/25 or more in a tape adhesion test after a pressure cooker test based on JIS K5600 of the electromagnetic shield member. Mounting board. The electronic component mounting board according to any one of claims 1 to 3, wherein the surface layer of the electromagnetic wave shield member has a kurtosis of 1 to 8 measured according to JIS B0601; 2001. The binder resin is obtained by thermocompression bonding a binder resin precursor containing a thermosetting resin and a curable compound having a functional group capable of crosslinking with the reactive functional group of the thermosetting resin. The electronic component mounting board according to claim 1, wherein the electronic component mounting board is provided. The electronic component mounting board according to claim 1, wherein the electromagnetic wave shield member has a film thickness of 10 to 200 μm. The electronic component mounting board according to claim 1, wherein acicular particles and/or dendrite particles are contained in an amount of 50% by mass or less in 100% by mass of the conductive filler. An electronic device on which the electronic component mounting board according to claim 1 is mounted.