JP2014110217A - Electronic device and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device capable of easily connecting between a minute terminal of a battery and an external terminal.SOLUTION: The electronic device includes: a battery including an electrode pad formation area 1x having a positive electrode pad 1a and a negative electrode pad 1b formed thereon; an anisotropic conductive film 4 stuck on the positive electrode pad 1a and the negative electrode pad 1b; first waiting 9a and second wiring 9b respectively formed upward of the positive electrode pad 1a and the negative electrode pad 1b of the anisotropic conductive film 4; a thermoelectric element 2 having a positive electrode terminal 2a and a negative electrode terminal 2b; third wiring 9d and fourth wiring 9d respectively connected to the positive electrode terminal 2a and the negative electrode terminal 2b of the thermoelectric element 2; and heat conduction patterns 9a, 9b formed on an area from the upward of the thermoelectric element 2 to the anisotropic conductive film 4.

Description

  The present invention relates to an electronic device and a manufacturing method thereof.

  As one form of a new secondary battery, an all-solid secondary battery in which all elements are formed of a solid has been developed and marketed.

  In a conventional lithium ion (Li) secondary battery, since a liquid electrolyte has been used as an electrolyte, there is a risk of liquid leakage, heating and ignition at a high temperature. Concerning the liquid leakage prevention structure, the sulfuric acid-based liquid and the electrode plate group are stored in the housing, the pin-shaped terminal connected to the electrode plate group is pulled out from the hole in the housing, and the gap between the hole and the pin-shaped terminal is embedded with resin. A structure for preventing liquid leakage is known. Also known is a structure in which a conductive resin agent is used as the resin, the conductive resin agent is wound around the pin-shaped terminal, and the pin-shaped terminal and the external output terminal are connected to each other via the conductive resin agent. .

  However, all solid-state secondary batteries have almost no such danger, and since no liquid is used, the deterioration of the electrolyte is very small, and the life of the battery capacity associated with charging / discharging is considered to be extremely long.

JP-A-6-196151

  The all-solid-state secondary battery is manufactured using a thin film process, and the positive electrode layer, negative electrode layer, electrolyte layer, and the like used are thin films on the order of μm. The battery capacity is about several mAh. In view of this, it is conceivable to take advantage of such shape features and integrate them in combination with other power generation devices to form a single chip. When the generated electric power is relatively small, the capacity of the battery required for storing the electric power may be small. For example, an all-solid-state secondary battery can be said to be a suitable power storage technique when the amount of power generation is small, such as energy harvesting, and power generation is performed not intermittently but intermittently.

  However, the size of an all-solid-state secondary battery used for such an application may be as small as several millimeters, for example, and it is difficult to connect fine terminals appearing on the surface to external terminals.

  The objective of this invention is providing the electronic device which can connect the fine terminal and external terminal of a battery easily, and its manufacturing method.

According to one aspect of the present embodiment, a battery having an electrode pad forming region in which a positive electrode pad and a negative electrode pad are formed, and an anisotropic conductive material attached on the positive electrode pad and the negative electrode pad. A film, a first wiring formed above each of the positive electrode pad and the negative electrode pad of the anisotropic conductive film, a second wiring, a thermoelectric element having a positive electrode terminal and a negative electrode terminal, A third wiring and a fourth wiring respectively connected to the positive electrode terminal and the negative electrode terminal of the thermoelectric element; and a heat conduction pattern formed in a range from the top of the thermoelectric element to the anisotropic conductive film; , An electronic device is provided.
The objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention.

  According to this embodiment, the fine terminal of a battery and an external terminal can be connected easily.

FIG. 1 is a plan view illustrating an example of an electronic component used in the electronic device according to the first embodiment. 2A and 2B are side cross-sectional views illustrating an example of a method for manufacturing an electronic device according to the first embodiment. 3A to 3D are side cross-sectional views illustrating an example of a method for manufacturing an electronic device according to the first embodiment. 4A to 4C are side cross-sectional views illustrating an example of a method for manufacturing an electronic device according to the first embodiment. FIG. 5 is a plan view illustrating an example of a heat treatment in the electronic device manufacturing method according to the first embodiment. FIG. 6 is a side cross-sectional view showing an example of a heat treatment in the electronic device manufacturing method according to the first embodiment. 7A to 7C are perspective views illustrating an example of contour lines of a temperature distribution by heat treatment used in the method for manufacturing an electronic device according to the first embodiment. FIG. 8 is a perspective view showing an example of an electronic circuit block diagram of the electronic device according to the first embodiment. FIG. 9 is a side sectional view showing an example of a side sectional view of the electronic device according to the first embodiment. FIG. 10 is a plan view illustrating an example of a heat treatment in the electronic device and the manufacturing method thereof according to the second embodiment. FIG. 11 is a plan view illustrating a first modification of the electronic device according to the second embodiment and an example of a heat treatment in the manufacturing method thereof. FIG. 12 is a plan view illustrating an example of a heat treatment in a second modification of the electronic device according to the second embodiment and a method for manufacturing the electronic device. FIG. 13 is a side sectional view showing an example of heat treatment in the electronic device and the manufacturing method thereof according to the third embodiment. 14A to 14D are side cross-sectional views illustrating an example of a method for manufacturing an electronic device according to a comparative example.

  Embodiments will be described below with reference to the drawings. In the drawings, similar components are given the same reference numerals.

(First embodiment)
FIG. 1 is a plan view illustrating an example of an element used in the electronic device according to the first embodiment, and FIGS. 2 to 4 and 6 are diagrams illustrating an example of a manufacturing process of the electronic device according to the first embodiment. Sectional drawing and FIG. 5 are top views which show an example of the manufacturing process of the electronic device which concerns on 1st Embodiment.

  FIGS. 1A, 1B, and 1C are plan views showing the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip component 3, respectively, and are arranged and integrated on the same plane.

  An all solid state secondary battery 1 shown in FIG. 1A is a lithium ion battery having a planar square shape with a side of 10 mm or less, for example, and is thinly formed in a stepped manner at one end with respect to the first surface of the main body. Electrode pad forming region 1x. The step with respect to the first surface of the electrode pad forming region 1x is formed with respect to the first surface of the all-solid-state secondary battery 1, for example, several tens μm to several hundreds μm. On the electrode pad forming region 1x, a pair of electrode pads made of metal, for example, aluminum, that is, a positive electrode pad 1a and a negative electrode pad 1b are exposed and formed thereon, and the anisotropic conductive film 4 is formed thereon. Is pasted. The all-solid-state secondary battery 1 is, for example, a Li all-solid-state secondary battery. For example, a sulfide-based material is used as the solid electrolyte housed therein, and the positive electrode material connected to the positive electrode pad 1a is, for example, Lithium cobalt oxide is used, and, for example, metallic lithium is used as a negative electrode material connected to the negative electrode pad 1b.

  The thermoelectric element 2 shown in FIG. 1 (b) has an electrode terminal forming region 2x that is thinly formed stepwise with respect to the first surface of the main body, and the terminal forming region 2x has a pair of metals formed from metal. The terminals, that is, the positive electrode terminal 2a and the negative electrode terminal 2b are exposed. The step in the terminal formation region 2x is formed with respect to the first surface of the thermoelectric element 2, for example, several tens μm to several hundreds μm. The thermoelectric element 2 has a structure in which power is output from the positive electrode terminal 2a and the negative electrode terminal 2b by the Seebeck effect, and heat is generated and cooled by the Peltier effect by applying a voltage between the positive electrode terminal 2a and the negative electrode terminal 2b. have.

  The thermoelectric element 2 has, for example, a plurality of columnar thermoelectric effect layers such as bismuth / tellurium-based materials and bismuth / antimony-based materials, and electrodes (not shown) are formed on the upper and lower sides of the thermoelectric elements 2. It is electrically connected to the electrode terminal 2b. The thermoelectric element 2 is sandwiched between heat conductive plates 2c and 2d formed of silicon (semiconductor) having high thermal conductivity or an insulating material.

  The chip component 3 shown in FIG. 1C is, for example, a chip capacitor and chip resistor necessary for power storage control of the all-solid-state secondary battery 1, and first and second electrode terminals 3a and 3b are provided at both ends thereof. Is formed.

  The first surfaces of the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip component 3 are attached and disposed on the foamable adhesive sheet 6 on the upper surface of the support plate 5 as shown in FIG. ing. The electrode pad formation region 1x of the all-solid-state secondary battery 1 and the terminal formation region 2x of the thermoelectric element 2 are both opposed to the support plate 5, and a gap is formed between the foamable adhesive sheet 6. Further, the electrode pad formation region 1x of the all-solid-state secondary battery 1 and the terminal formation region 2x of the thermoelectric element 2 are oriented in the same direction. In the case where a plurality of parts such as the all-solid-state secondary battery 1 are arranged on the foamable pressure-sensitive adhesive sheet 6, it is generally arranged accurately using a mounter.

  When the all-solid-state secondary battery 1 is attached, the anisotropic conductive film 4 is sandwiched between the foamable adhesive sheet 6 and the positive electrode pad 1a and the negative electrode pad 1b. The anisotropic conductive film 4 is a film formed by forming a material in which conductive fine metal particles (conductive filler) are mixed with a thermosetting resin (binder) into a film shape, and is an insulator in an initial state, The resistance is lowered by heating and pressurizing within a specified temperature range, for example, 180 ° C. to 200 ° C. As the anisotropic conductive film 4, for example, a film having substantially the same thickness as the step of the first surface and the electrode pad forming region 1x in the all-solid-state secondary battery 1 is used. The anisotropic conductive film 4 is not limited to a single layer, and a plurality of layers may be used to adjust the thickness to the steps.

Subsequently, the support plate 5 and the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip component 3 thereon are placed in a cavity of a mold for molding (not shown). The cavity has a rectangular parallelepiped shape in which a space exists on the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip component 3. In this state, for example, a silica filler-containing epoxy resin is injected into the cavity as a mold resin, and is pressed into a mold, for example, for several minutes while heating at about 120 ° C. in a vacuum. Thereby, as illustrated in FIG. 2B, the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip component 3 on the foamable adhesive sheet 6 are covered and embedded in the rectangular parallelepiped mold resin layer 7. It becomes a state.

  Thereafter, as shown in FIG. 3A, after the foamable adhesive sheet 6 is peeled from the first surface of the mold resin layer 7, the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip component 3, the mold resin layer 7 Is cured at 150 ° C. for about 1 hour. As a result, the first surfaces of the anisotropic conductive film 4, the all solid state secondary battery 1, the thermoelectric element 2, and the chip component 3 are exposed from the first surface of the mold resin layer 7, but the all solid state secondary battery 1. The positive electrode pad 1a and the negative electrode pad 1b and the positive electrode terminal 2a and the negative electrode terminal 2b of the thermoelectric element 2 are not exposed.

  Subsequently, as illustrated in FIG. 3B, gliding is performed on the second surface of the mold resin layer 7 to expose the second surface of the thermoelectric element 2. Thereby, the first surface and the second surface of the thermoelectric element 2, that is, the pair of heat conduction plates 2 c and 2 d are exposed from the first surface and the second surface of the mold resin layer 7. Since the thermoelectric element 2 is formed thicker than the all-solid-state secondary battery 1 and the chip part 3, the second surface of the all-solid-state secondary battery 1 and the chip part 3 after the gliding is molded resin. The state covered with the layer 7 is maintained.

Further, as illustrated in FIG. 3C, a part of the first surface of the mold resin layer 7 is irradiated with laser light, and an opening is formed on each of the positive electrode terminal 2a and the negative electrode terminal 2b of the thermoelectric element 2. The portions 7a and 7b are formed, and the positive electrode terminal 2a and the negative electrode terminal 2b are exposed. As the laser light source, for example, a CO ₂ laser is used.

  Next, as illustrated in FIG. 3D, the mold resin layer 7, the all-solid-state secondary battery 1, the anisotropic conductive film 4, the thermoelectric element 2, and the opening 7 a on the first surface of the chip component 3. A metal seed layer 8 is formed on the positive electrode terminal 2a and the negative electrode terminal 2b at the bottom of 7b. As the seed layer 8, for example, a copper (Cu) layer is formed to a thickness of about several μm by sputtering. Further, a photoresist is applied on the seed layer 8, and this is exposed and developed to form a resist pattern 10. The resist pattern 10 is formed on the heat conductive substrate 2c from the first opening 10a and the negative electrode pad 1b formed in a range from the upper side of the positive electrode pad 1a of the all-solid-state secondary battery 1 to the half on the heat conductive plate 2c. It has the 2nd opening part 10b formed in the range which reaches the other half. In this case, the first opening 10a and the second opening 10b are formed at an interval. The resist pattern 10 includes third and fourth openings 10c and 10d drawn laterally from the positive electrode terminal 2a and the negative electrode terminal 2b of the thermoelectric element 2, and the first and second electrode pads of the chip component 3. It has the 5th and 6th opening parts 10e and 10f pulled out from 3a and 3b, respectively.

  Subsequently, as illustrated in FIG. 4A, an electroplating method using the seed layer 8 as an electrode is used to convert a metal having a good thermal conductivity and a low resistance, such as a Cu film, into the first to sixth openings 10a. -10 f, for example, to a thickness of about 20 μm. Thereby, the Cu film in the first opening 10a and the seed layer 8 therebelow are used as the first heat conduction pattern / wiring 9a, and the Cu film in the second opening 10b and the seed layer therebelow are used. 8 is used as the second heat conduction pattern and wiring 9b, which are separated from each other. Further, the third and fourth electrodes in which the Cu films in the third and fourth openings 10c and 10d and the seed layer 8 therebelow are connected to the positive electrode terminal 2a and the negative electrode terminal 2b of the thermoelectric element 2, respectively. Used as wirings 9c and 9d. Further, the fifth and sixth openings 10e and 10f, and the seed layer 8 thereunder are connected to the first and second electrode pads 3a and 3b of the chip-like component 3, respectively. Used as sixth wirings 9e and 9f.

Next, as illustrated in FIG. 4B, after the resist pattern 10 is removed, the first and second heat conduction pattern / wirings 9a and 9b and the third to sixth wirings 9c to 9f are used as masks. In use, the exposed seed layer 8 is etched. Thereby, as illustrated in FIGS. 4C and 5, the first and second heat conduction pattern and wirings 9 a and 9 b and the third to sixth electrode wirings 9 c to 9 f are separated in shape. .

  After the basic shape of the electronic device is completed as described above, the first heat conduction pattern / wiring 9a is electrically connected to the positive electrode pad 1a of the all-solid-state secondary battery 1 by the following method. Are electrically connected to the negative electrode pad 1 b of the all-solid-state secondary battery 1.

First, as shown in FIG. 5, with the first surface of the mold resin layer 7 facing upward, the mold resin layer 7 including the all-solid-state secondary battery 1, the thermoelectric element 2 and the like is mounted on the mounting table 13 as a power supply module. To do. In this state, the second surface of the mold resin layer 7 is heated by the heater in the mounting table 13. The heating temperature T ₀ is set to a temperature at which the anisotropic conductive film 4 is not cured and lithium (Li) contained in the all-solid secondary battery 1 is not melted, for example, 160 ° C. Then, as shown in the cross section of FIG. 6, the first surface of the anisotropic conductive film 4 is pressed with a fluororesin rod 14 or the like having poor thermal conductivity via the positive electrode pad 1a and the negative electrode pad 1b, and the thermoelectric element. The DC power source 12 is connected to the second and fourth wirings 9c and 9d, and the thermoelectric element 2 is caused to generate heat by the Peltier effect. For example, the voltage applied to the third and fourth wirings 9c and 9d is about 5.6V. The application time is set to about 20 seconds to 1 minute.

  Thereby, the heat T generated in the thermoelectric element 2 is conducted above the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 through the first and second heat conduction pattern and wirings 9a and 9b. Is done. Thereby, the part on the positive electrode pad 1a and the negative electrode pad 1b of the anisotropic conductive film 4 is heated locally, and it cures with the pressure added from the top. Accordingly, in the portion of the anisotropic conductive film 4 above the positive electrode pad 1a and the negative electrode pad 1b, a conductive path is formed by connecting the plated layers of fine metal particles of the internal particles to each other. Further, insulation is maintained between the fine metal particles in the portion where no pressure is applied. As a result, in the anisotropic conductive film 4, the thickness direction conductivity is secured on the positive electrode pad 1 a and the negative electrode pad 1 b to form the low-resistance conductive portions 4 a and 4 b, and in other regions, insulation is performed. Is retained.

  After the first and second heat conduction patterns / wirings 9a and 9b are formed in this way, a current is passed through the thermoelectric element 2 to operate as a Peltier element, so that the top of the positive electrode pad 1a and the negative electrode pad 1b. This part is locally heated and further pressed. Thereby, the positive electrode pad 1a of the all-solid-state secondary battery 1 and the first heat conduction pattern / wiring 9a, and the second heat conduction pattern / wiring 9b and the negative electrode pad 1b are electrically connected.

  Here, the state when heated as described above is model-calculated. In this case, the all-solid-state secondary battery 1 having a length of 5 mm, a width of 5 mm, and a thickness of 300 μm, and a thermoelectric element 2 having a length of 4248 μm, a width of 3364 μm, and a thickness of 1090 μm are arranged with an interval of 500 μm. The positive electrode pad 1a and the negative electrode pad 1b on the electrode pad forming region 1x of the all-solid-state secondary battery 1 are 2 μm thick, 150 μm long, and 150 μm wide. Further, the step of the electrode pad forming region 1x of the all-solid-state secondary battery 1 with respect to the first surface is 35 μm, the positive electrode pad 1a and the negative electrode pad 1b having a thickness of 2 μm thereon, and the difference of 35 μm in thickness thereon. The isotropic conductive film 4 is pressed against the fluororesin rod 14. In this case, the pressure applied to the anisotropic conductive film 4 is calculated as about 3.4 MPa. In this case, when model number CP9842K manufactured by Sony Chemical & Information Device Co., Ltd. is used as the anisotropic conductive film 4, a pressure of 2 MPa to 4 MPa, which is one of the curing conditions, is satisfied.

As described above, when the second surface of the mold resin layer 7 is externally heated at a temperature of 160 ° C. and about 5.6 V is applied between the positive electrode terminal 2 a and the negative electrode terminal 2 b of the thermoelectric element 2, the thermoelectric element 2 Is heated to about 200 ° C. The contour line indicating the temperature distribution of the temperature at this time is, for example, FIG.
It becomes like a). In this case, heat is transmitted from the first surface of the thermoelectric element 2 to the positive electrode pad 1a and the negative electrode pad 1b on the all-solid-state secondary battery 1 via the first and second heat conduction patterns / wirings 9a and 9b. I understand that.

  Furthermore, when only the anisotropic conductive film 4 is taken out and temperature distribution is shown, it will become like FIG.7 (b). It can be seen that the anisotropic conductive film 4 is heated to 180 ° C. to 200 ° C. and the curing conditions of 180 ° C. to 200 ° C. can be achieved. In addition, since the whole module is heated at less than 180 degreeC, the heat_generation | fever temperature of the heating thermoelectric element 2 is a temperature which can be added in order to achieve the temperature of the anisotropic conductive film 4 in the range of 180 degreeC-200 degreeC. What is necessary is just to be less than 200 degreeC.

  On the other hand, a temperature distribution obtained by taking out only the thermoelectric element 2 and the all-solid-state secondary battery 1 is as shown in FIG. 7C, and the temperature of the region of the all-solid-state secondary battery 1 is from 160 ° C. to less than about 180 ° C. You can see that it is kept in range. That is, according to the above example, only the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 are locally heated and pressurized to form the conductive portions 4a and 4b on them, In this part, a high resistance region is formed. Therefore, as in this embodiment, fine local heating of a size level of several hundred μm is generated from the nearby thermoelectric element 2, so that a special heating tool is unnecessary. Moreover, heating by the Peltier effect can be performed easily and accurately by supplying current, which is very effective.

  Further, heat conduction pattern and wirings 9a and 9b are formed in a region from the first surface of the thermoelectric element 2 to the positive electrode pad 1a and the negative electrode pad 1b on the first surface of the all-solid-state secondary battery 1. Therefore, the degree of integration increases and the device can be miniaturized. When the all-solid-state secondary battery 1, the electrothermal element 2, and the chip-like component 3 integrated through the mold resin layer 7 are power supply modules, the formation of the conductive portions 4 a and 4 b in the anisotropic conductive film 4 is as follows. This can be done immediately before installing the module. For this reason, the all-solid-state secondary battery 1 can be kept unused for a long time, and early deterioration of the all-solid-state secondary battery 1 can be prevented. In addition, since the positive electrode pad 1a and the negative electrode pad 1b are covered with the anisotropic conductive film 4 in an insulating state, a new measure for preventing a short circuit becomes unnecessary and handling becomes easy.

  Next, an example of a circuit for accumulating the electric power generated by the thermoelectric element 2 in the all solid state secondary battery 1 and performing the above heat treatment will be described.

  In the manufacturing process of the electronic device described above, after the wirings 9a to 9f are formed, a current is passed through the thermoelectric element 2 so as to operate as a Peltier element, so that the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 are localized. Heating is taking place. When the directions of the high temperature side and the low temperature side of the thermoelectric element 2 with respect to the heat conductive plates 2c and 2d are determined, the direction of current due to the Seebeck effect as the thermoelectric element 2 and the direction of current as the Peltier element are reversed. Therefore, this must be considered for the circuit.

  An example of a circuit block when such a method is employed is shown in FIG. Since the output voltage due to the Seebeck effect of the thermoelectric element 2 is low, the boost converter circuit 21 is connected to the positive electrode terminal 2 a and the negative electrode terminal 2 b of the thermoelectric element 2. As the boost converter circuit 21, for example, model number LTC3109 manufactured by Linear Technology is used. The output terminal of the boost converter circuit 21 is connected to the input terminal of a lithium battery control IC 22 having a shunt battery storage circuit. The first output terminal of the lithium battery control IC 22 is connected to the positive electrode pad 1 a and the negative electrode pad 1 b of the all solid state secondary battery 1. Further, the lithium battery control IC 22 has a second output terminal 22 a that outputs the power stored in the all-solid-state secondary electrons 1 or the power generated by the thermoelectric element 2.

  The electric power generated by the thermoelectric element 2 is boosted to, for example, about 5 V by the boost converter circuit 21 and output, and is stored in the all-solid-state secondary battery 1 under the control of the lithium battery control IC 22 having the shunt battery storage circuit. When the all-solid-state secondary battery 1 is fully charged, the lithium battery control IC 22 outputs power to the second output terminal 22a. In this case, the final output voltage is the output voltage of the all-solid-state secondary battery 1, for example, about 4.1V.

  In such a configuration, the third and fourth wirings 9c and 9d are connected between the thermoelectric element 2 and the step-up converter circuit 21, and a voltage (Vheat-Vheat) is applied to them to supply the current I, thereby providing thermoelectricity. The element 2 is heated to form conductive portions 4 a and 4 b on the anisotropic conductive film 4. At the same time, the all-solid-state secondary battery 1 can be initially charged via the boost converter circuit 21 and the lithium battery control IC 22. The charging direction and the heating current supply direction are indicated by broken lines in FIG.

  After the conductive portions 4a and 4b are formed in the anisotropic conductive film 4 and the conduction is completed, the current of the power output from the thermoelectric element 2 is as shown by the arrow in FIG. 9 and the one-dot chain line in FIG. The current is reversed between positive and negative depending on the heating / cooling direction. However, since the LTC3109, which is the boost converter circuit 21 described above, can boost and output the same polarity regardless of the input polarity, it is convenient when the thermoelectric element 2 is used as a Peltier element. .

  In the above description, the all-solid secondary battery 1 is taken as an example of the battery. However, if the battery can be integrated, for example, a secondary battery using an electrolyte instead of the all-solid secondary battery 1 or A primary battery may be adopted. The same applies to the following embodiments.

  As described above, according to the present embodiment, the anisotropic conductive film 4 is sandwiched between the electrode pads 1a and 1b of the all-solid-state secondary battery 1 and the wirings 9a and 9b, and thereafter the electrode pads 1a and 1b are placed on the electrode pads 1a and 1b. The method of locally heating and pressurizing is adopted. Thus, after the wiring is formed, the conductive connection between the all-solid-state secondary battery electrode 1 and the wirings 9a and 9b can be irreversibly ensured. In addition, by this method, the insulating property of the all-solid-state secondary battery 1 is maintained until the wirings 9a and 9b are formed by the plating process, and a high-temperature process that may deteriorate the all-solid-state secondary battery 1 is avoided. It becomes possible. Therefore, the reliability of the battery can be maintained as compared with the prior art, which greatly contributes to the manufacturing method of the electronic device using the secondary battery. Moreover, when heating the electrode pads 1a, 1b using the thermoelectric element 2, it is possible to supply power to all the individual secondary batteries 1, so that the anisotropic conductive film 4 is locally heated. A new element becomes unnecessary and the conductive treatment becomes easy.

(Second Embodiment)
FIG. 10 is a plan view showing an electronic device according to the second embodiment. In FIG. 10, the same reference numerals as those in FIGS. 1 to 6 denote the same elements.

  In FIG. 10, a heat conduction pattern 9j of a metal having a good thermal conductivity, for example, Cu, is formed on the first surface of the thermoelectric element 2. The heat conductive pattern 9j extends to a region between the positive electrode pad 1a and the negative electrode pad 1b in the anisotropic conductive film 4 attached on the electrode pad forming region 1x of the all-solid-state secondary battery 1. The shape on and around the anisotropic conductive film 4 is shown as a substantially U-shape that exposes a portion of the anisotropic conductive film 4 between the positive electrode pad 1a and the negative electrode pad 1b. The shape may not be exposed.

  Further, on each of the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1, a plus side wiring 9g and a minus side wiring 9h are connected. The heat conduction pattern 9j, the plus wiring 9g, and the minus wiring 9h are obtained by changing the shape of the openings 10a and 10b of the resist pattern 10 shown in FIG. 3D and laminating a Cu film therein by an electrolytic plating method. It is formed.

Further, after the patterning of the seed layer 8 as shown in FIG. 4 is completed, the mold resin layer 7 and the all-solid-state secondary battery 1 are heated on the mounting table 13 to a temperature T ₀ below the lithium melting point, for example, about 160 ° C. To do. Further, the negative wiring 9g and the positive wiring 9h immediately above the positive electrode pad 1a and the negative electrode pad 1b are pressed by the fluororesin rod 14 under the same conditions as in the first embodiment. At the same time, heat is generated by flowing electricity to the thermoelectric element 2, and the heat T is transmitted to the vicinity of the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 through the heat conduction pattern 9j. The temperature on the anisotropic conductive film 4 is increased to 180 ° C. to 200 ° C. As a result, the anisotropic conductive film 4 is cured immediately above the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1, thereby forming conductive portions 4a and 4b. As a result, the positive electrode pad 1a is electrically connected to the plus wiring 9g, and the negative electrode pad 1b is electrically connected to the minus wiring 9h.

  As described above, according to the present embodiment, the heat conduction pattern 9j disposed on the thermoelectric element 2 is extended to the vicinity of the electrode pads 1a and 1b of the all-solid-state secondary battery 1, and is applied to the positive electrode pad 1a and the negative electrode pad 1b. Does not extend. Thereby, the freedom degree of the wiring electrically connected to the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 can be increased while maintaining the operational effects shown in the first embodiment. .

  In the present embodiment, the circuit shown in FIG. 8 may be employed. In this case, as shown in FIG. 9, the polarity can be made uniform even if the charging current to the all-solid-state secondary battery 1 is reversed between positive and negative depending on the heating and cooling directions above and below the heating element 2.

  By the way, as shown in FIG. 11, when the positive electrode pad 1a and the negative electrode pad 1b approach in the electrode pad formation region 1x of the all-solid-state secondary battery 1 and there are empty spaces near both ends, the space Alternatively, the anisotropic conductive film 4 may protrude. In this case, the tip of the heat conduction pattern 9j is connected to the portion of the anisotropic conductive film 4 that protrudes toward both ends of the electrode pad formation region 1x with respect to the positive electrode pad 1a and the negative electrode pad 1b. Conductive portions 4a and 4b are formed.

  In addition, as shown in FIG. 12, when there is a vacant space near the tips of the positive electrode pad 1a and the negative electrode pad 1b in the electrode pad formation region 1x of the all-solid-state secondary battery 1, anisotropic conductivity is generated in the space. The film 4 may protrude. In this case, the tip portion of the heat conduction pattern 9j is connected to the portion of the anisotropic conductive film 4 that protrudes toward the tip with respect to the positive electrode pad 1a and the negative electrode pad 1b, and heat is conducted to conduct the conductive portion 4a. 4b.

  As shown in FIGS. 11 and 12, in order to conduct heat from one heat conduction pattern 9j to the anisotropic conductive film 4 in the vicinity of the positive electrode pad 1a and the negative electrode pad 1b, the positive electrode pad 1a and The top of the negative electrode pad 1b is pressed by the fluororesin rod 14 to form the conductive portions 4a and 4b.

(Third embodiment)
FIG. 13 is a side sectional view showing an electronic device according to the third embodiment and a heating method in the manufacturing process thereof. In FIG. 13, the same reference numerals as those in FIGS. 1 to 6 denote the same elements.

In FIG. 13, in the anisotropic conductive film 4 attached to the electrode pad formation region 1x of the all-solid-state secondary battery 1, negative wiring 9g and regions above the positive electrode pad 1a and the negative electrode pad 1b, respectively, A plus wiring 9h is formed. The plus wiring 9g and the minus wiring 9h are formed by changing the shapes of the openings 10a and 10b of the resist pattern 10 shown in FIG. 3D and laminating a Cu film therein by an electrolytic plating method. In the present embodiment, a heat conduction pattern is not formed on the thermoelectric element 2.

  Then, a Cu film is formed, and then the seed layer 8 is partially etched as in the first embodiment. Thereafter, using a laser irradiation apparatus, for example, a laser fine soldering apparatus, laser light is irradiated from the center of each of the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 toward a region having a diameter of 150 μm. Then, local heating is performed on the negative wiring 9g and the positive wiring 9h.

  As for the heating temperature in this case, the temperature of the anisotropic conductive film 4 at the portion immediately above the positive electrode pad 1a and the negative electrode pad 1b can be set to about 200 ° C. The surface of 9h is adjusted to be about 150 ° C. by cooling by heat conduction, for example, by air cooling. Naturally, laser light irradiation is not performed at a temperature until the minus wiring 9g and the plus wiring 9h are melted. After the anisotropic conductive film 4 is heated by laser light, the negative electrode 9g and the positive wire 9h in the region immediately above the positive electrode pad 1a and the negative electrode pad 1b are fluorinated resin under the conditions shown in the first embodiment. You may pressurize with the stick | rod 14. The fluororesin rod 14 may be heated.

  By such local heating, low resistance conductive portions 4a and 4b are formed in the anisotropic conductive film 4, the positive electrode pad 1a is electrically connected to the positive wiring 9g, and the negative wiring 9h is connected to the negative electrode pad 1b. Electrically connected.

  As described above, according to the present embodiment, in the all-solid-state secondary battery 1, the anisotropic conductive film 4 is provided between the positive electrode pad 1a and the positive wiring 9g and between the negative electrode pad 1b and the negative wiring 9h. The structure that sandwiches is adopted. Furthermore, the positive wiring 9g and the negative wiring 9h immediately above the positive electrode pad 1a and the negative electrode pad 1b are irradiated with laser light to locally heat the anisotropic conductive film 4 thereunder, and then pressed to form a conductive portion 4a. 4b. As a result, the same effects as those of the first embodiment can be obtained, and the wirings 9g and 9h can be well connected to the fine positive electrode pad 1a and the negative electrode pad 1b.

  By the way, in 1st, 2nd and 3rd embodiment, an opening part is formed on each of the positive electrode pad 1a and the negative electrode pad 1b among the mold resin layers 7 which cover the all-solid-state secondary battery 1, and opening The method of connecting the wiring directly through the section is not adopted. This is to prevent a short circuit between the positive electrode pad 1a and the negative electrode pad 1b which occurs in the comparative example shown below.

  In the comparative example, first, as shown in FIG. 14A, the all-solid-state secondary battery 1, the thermoelectric element 2, and the chip-like component 3 are attached to the foamable adhesive sheet 6 on the upper surface of the support plate 5. In this case, a gap exists between the positive electrode pad 1 a and the negative electrode pad 1 b of the all-solid-state secondary battery 1 and the foamable adhesive sheet 6. In this state, when the mold resin layer 7 is formed on the foamable adhesive sheet 6, the mold resin layer 7 is interposed between the positive electrode pad 1 a and the negative electrode pad 1 b of the all-solid-state secondary battery 1 and the foamable adhesive sheet 6. Will intervene.

  Thereafter, the mold resin layer 7, the all-solid-state secondary battery 1 and the like are peeled off from the foamable pressure-sensitive adhesive sheet 6, and the second surface side of the mold resin layer 7 is grinded to reduce the thickness of the second surface of the power generating element 2. Expose. Accordingly, as shown in FIG. 14B, the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1 are covered with the mold resin layer 7.

Subsequently, as shown in FIG. 14C, openings 7c and 7d are formed by irradiating laser light on the positive electrode pad 1a and the negative electrode pad 1b of the all-solid-state secondary battery 1. Further, similarly to the first embodiment, openings 7a and 7b are formed on the positive electrode terminal 2a and the negative electrode terminal 2b of the thermoelectric element 2, and thereafter, as shown in FIG. A Cu seed layer 8 is formed on the first surface of the element 2 and the chip-like component 3 and on the inner surfaces of the openings 7a to 7d. Thereafter, although not particularly shown, a plus wiring 9g, a minus wiring 9h, etc. are formed on the seed layer 8 as in the third embodiment, and the seed layer 8 is further patterned.

  According to such a process, when the seed layer 8 is formed in the openings 7 a to 7 d and on the mold resin layer 7, the positive electrode terminal 2 a and the negative electrode terminal 2 b of the all-solid-state secondary battery 1 pass through the seed layer 8. Will cause a short circuit. Since such a short circuit is maintained for a long time from the formation of the seed layer 8 to the etching, the reliability of the all-solid-state secondary battery 1 is deteriorated due to a fatal deterioration or a shortened life.

  As a countermeasure, the positive electrode pad 1a and the negative electrode pad 1b are protected with an insulating material such as a resist before the molding resin layer 7 is formed. A method of connecting the electrode pad 1a and the negative electrode pad 1b with a conductive film is also conceivable. However, as described above, since the heat treatment is performed at 150 ° C. for at least 1 hour in the forming process of the mold resin layer 7 as described above, a resist material that can withstand this condition is necessary, but there is almost no such resist material. is there. Moreover, the process of removing the insulating film material later to form the conductive film is complicated and cannot be said to be an effective technique.

  On the other hand, a structure in which the anisotropic conductive film 4 is sandwiched between the electrode pads 1a and 1b of the all-solid-state secondary battery 1 and the wirings 9a, 9b, 9g, and 9h as in the above embodiment is employed, and the seed layer 8 is etched. After that, the anisotropic conductive film 4 is locally made conductive. For this reason, a short circuit between the positive electrode terminal 2a and the negative electrode terminal 2b of the all-solid-state secondary battery 1 due to the seed layer 8 is prevented by the anisotropic conductive film 4, and a complicated wiring formation step is not required. Moreover, the all-solid-state secondary battery 1 is electrically isolated before the anisotropic conductive film 4 is locally made conductive. Therefore, before the anisotropic conductive film 1 is made conductive, even if the positive wires 9a and 9g and the negative wires 9b and 9h connected to the all-solid-state secondary battery 1 are accidentally short-circuited from the outside, those wires The lower positive electrode pad 1a and the negative electrode pad 1b are not short-circuited, and management becomes easy. Moreover, since heat is only locally applied to the anisotropic conductive film 4 in the process after the wiring is formed, the electrode pads 1a and 1b of the all-solid-state secondary battery 1 may be locally heated to deteriorate the battery. High-temperature heating can be avoided, whereby deterioration of the all-solid secondary battery 1 can be prevented.

  All examples and conditional expressions given here are intended to help the reader understand the inventions and concepts that have contributed to the promotion of technology, such examples and It is interpreted without being limited to the conditions, and the organization of such examples in the specification is not related to showing the superiority or inferiority of the present invention. While embodiments of the present invention have been described in detail, it will be understood that various changes, substitutions and variations can be made thereto without departing from the spirit and scope of the invention.

Next, an embodiment of the present invention will be additionally described.
(Appendix 1) A battery having an electrode pad forming region in which a positive electrode pad and a negative electrode pad are formed, an anisotropic conductive film attached on the positive electrode pad and the negative electrode pad, and the anisotropy A first wiring and a second wiring formed above each of the positive electrode pad and the negative electrode pad of the conductive film, a thermoelectric element having a positive electrode terminal and a negative electrode terminal, and the positive electrode of the thermoelectric element An electronic device comprising: a third wiring and a fourth wiring respectively connected to a terminal and the negative electrode terminal; and a heat conduction pattern formed in a range from the thermoelectric element to the anisotropic conductive film.
(Supplementary note 2) The electronic device according to supplementary note 1, wherein the anisotropic conductive film has a first conductive portion and a second conductive portion on each of the positive electrode pad and the negative electrode pad.
(Additional remark 3) The said heat conductive pattern has the 1st heat conductive pattern which serves as said 1st wiring, and the 2nd heat conductive pattern which also serves as said 2nd wiring, The electron of Additional remark 1 or Additional remark 2 characterized by the above-mentioned device.
(Supplementary note 4) In Supplementary note 1 or Supplementary note 2, the end portion of the thermal conduction pattern is connected to the anisotropic conductive film in a region in the vicinity of the positive electrode pad and the negative electrode pad. The electronic device described.
(Supplementary Note 5) The battery is a secondary battery, and each of the first wiring and the second wiring is electrically connected to the positive electrode terminal and the negative electrode terminal of the thermoelectric element via a battery control semiconductor element and a booster circuit. The electronic device according to any one of Supplementary Note 1 to Supplementary Note 4, wherein the electronic device is connected electrically.
(Additional remark 6) It has the mold resin which covers the said battery, the said anisotropic conductive film, and the said thermoelectric element in the state which exposed the one surface of the said anisotropic conductive film, and both surfaces of the said thermoelectric element. Or an electronic device according to any one of appendix 5.
(Additional remark 7) The process of arrange | positioning a battery and a thermoelectric element, The process of sticking an anisotropic conductive film on the positive electrode pad and negative electrode pad which are formed in the electrode pad formation area of the said battery, The said anisotropic conductivity Forming a first wiring and a second wiring connected to a first region and a second region on each of the positive electrode pad and the negative electrode pad of the film, and the anisotropy from above the thermoelectric element A process of forming a heat conduction pattern over the conductive film, and conducting the first heat generated by the piezoelectric effect in the thermoelectric element by supplying current to the anisotropic conductive film through the heat conduction pattern. And increasing the temperature of the first region on the positive electrode pad and the second region on the negative electrode pad of the anisotropic conductive film, and increasing the temperature in the anisotropic conductive film. Shi Method for manufacturing an electronic device and a step of changing the first conductive portion and the second conductive portion by pressing through the second wiring and the first wiring each of the first region and the second region.
(Additional remark 8) The said anisotropic conductive film is supplied with the 2nd heat from the outside with the said 1st heat transmitted from the said heat conductive pattern, The manufacture of the electronic device of Additional remark 7 characterized by the above-mentioned. Method.
(Additional remark 9) The said battery WHEREIN: 1st temperature of the said electrode pad formation area is heated higher than 2nd temperature of another area | region, The manufacturing method of the electronic device of Additional remark 7 or Additional remark 8 characterized by the above-mentioned.
(Additional remark 10) The said 1st temperature is 180 degreeC or more, The manufacturing method of the electronic device of Additional remark 4 of Additional remark 9 characterized by the above-mentioned.
(Additional remark 11) Said 2nd temperature is less than 180 degreeC, The manufacturing method of the electronic device of Additional remark 9 or Additional remark 10 characterized by the above-mentioned.
(Additional remark 12) The said battery is a secondary battery, The said electric current sent through the said thermoelectric element is sent to the positive electrode pad and negative electrode pad of the said secondary battery through the said 1st heat conductive pattern and the said 2nd heat conductive pattern. The method of manufacturing an electronic device according to any one of appendix 7 to appendix 11, wherein the secondary battery is charged by flowing the battery.
(Supplementary note 13) Any one of Supplementary notes 7 to 12, wherein the thermal conduction pattern includes a first thermal conduction pattern that also serves as the first wiring and a second thermal conduction pattern that also serves as the second wiring. The manufacturing method of the electronic device as described in one.
(Additional remark 14) The edge part of the said heat conductive pattern is connected to the side part of the said 1st area | region of the said anisotropic conductive film, and the side part of the said 2nd area | region, The additional remark 7 thru | or the remark 12 characterized by the above-mentioned The manufacturing method of the electronic device as described in any one.
(Additional remark 15) The battery which has an electrode pad formation area in which a positive electrode pad and a negative electrode pad are formed, an anisotropic conductive film affixed on the positive electrode pad and the negative electrode pad, and the anisotropy An electronic device having a first wiring and a second wiring formed above each of the positive electrode pad and the negative electrode pad in a conductive film.
(Additional remark 16) The process of sticking an anisotropic conductive film on the positive electrode pad and negative electrode pad which are formed in the electrode pad formation area of a battery, The positive electrode pad and the negative electrode among the anisotropic conductive films Forming a first wiring and a second wiring over each of the pads; and heating the temperatures of the first region and the second region of the anisotropic conductive film on the positive electrode pad and the negative electrode pad And the first conductive part by pressing the first region and the second region of the anisotropic conductive film through the first wiring and the second wiring, respectively. And a step of forming a second conductive portion.

DESCRIPTION OF SYMBOLS 1 All-solid-state secondary battery 1a Positive electrode pattern 1b Negative electrode pattern 2 Thermoelectric element 2a Positive electrode terminal 2b Negative electrode terminal 3 Chip-shaped component 4 Anisotropic conductive film 4a, 4b Conductive part 5 Support plate 6 Foamable adhesive sheet 7 Mold Resin layer 8 Seed layers 9a, 9b, 9j Heat conduction pattern and wiring 9c, 9d, 9e, 9f, 9g, 9h Wiring 10 Resist pattern 12 Power supply 13 Mounting table 14 Fluoro resin rod 21 Boost converter circuit 22 Lithium battery control IC

Claims (7)

A battery having an electrode pad forming region in which a positive electrode pad and a negative electrode pad are formed;
An anisotropic conductive film affixed on the positive electrode pad and the negative electrode pad;
A first wiring and a second wiring formed above each of the positive electrode pad and the negative electrode pad of the anisotropic conductive film;
A thermoelectric element having a positive electrode terminal and a negative electrode terminal;
A third wiring and a fourth wiring respectively connected to the positive electrode terminal and the negative electrode terminal of the thermoelectric element;
A heat conduction pattern formed in a range from the thermoelectric element to the anisotropic conductive film;
An electronic device.   The electronic device according to claim 1, wherein the anisotropic conductive film has a first conductive portion and a second conductive portion on each of the positive electrode pad and the negative electrode pad.   3. The electronic device according to claim 1, wherein the thermal conduction pattern includes a first thermal conduction pattern that also serves as the first wiring and a second thermal conduction pattern that also serves as the second wiring. 4.   The end portion of the heat conduction pattern is connected to the anisotropic conductive film in a region in the vicinity of the positive electrode pad and the negative electrode pad. Electronic devices. Arranging the battery and the thermoelectric element;
Pasting an anisotropic conductive film on the positive electrode pad and the negative electrode pad formed in the electrode pad formation region of the battery;
Forming a first wiring and a second wiring connected to a first region and a second region on each of the positive electrode pad and the negative electrode pad of the anisotropic conductive film;
Forming a heat conduction pattern in a range from above the thermoelectric element to the anisotropic conductive film;
The first heat generated by the piezoelectric effect in the thermoelectric element by supplying current is conducted to the anisotropic conductive film through the thermal conduction pattern, and the anisotropic electrode on the positive electrode pad of the anisotropic conductive film. Increasing the temperature of the first region and the second region on the negative electrode pad;
In the anisotropic conductive film, the first conductive portion and the second conductive portion are pressed by pressing the first region and the second region, respectively, where the temperature is increased, through the first wiring and the second wiring. Changing process,
Manufacturing method of electronic device having   The method for manufacturing an electronic device according to claim 5, wherein the anisotropic conductive film is supplied with second heat from the outside together with the first heat transmitted from the heat conductive pattern.   7. The method of manufacturing an electronic device according to claim 5, wherein, in the battery, the first temperature in the electrode pad formation region is heated higher than the second temperature in the other region.

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