JP2019174127A - Heat flow flux sensor manufacturing method - Google Patents

Abstract

To provide a heat flow flux sensor manufacturing method capable of suppressing remaining of air bubbles on an inner side.SOLUTION: An insulation base material constituted by including a thermoplastic resin is filled with a conductive paste. A second protective member, the insulation base material, and a first protective member are arranged in this order so as to constitute a lamination body 70. Then, the lamination body 70 is pressurized from a laminating direction while being heated, so as to be integrated. Performance of integration includes: forming thermoelectric transducers 40, 50 from the conductive paste by pressurizing the lamination body 70 with the use of a press plate for regular heating; preliminarily cooling the lamination body 70 by pressurizing the lamination body 70 with the use of a press plate 131 for preliminary cooling; and regularly cooling the lamination body 70 by pressurizing the lamination body 70 with the use of a press plate for regular cooling after preliminarily cooling. In preliminarily cooling, a temperature for preliminary cooling and a pressurization force for preliminary cooling are set to enable crushing of air bubbles.SELECTED DRAWING: Figure 6D

Description

  The present invention relates to a method for manufacturing a heat flux sensor.

  Conventionally, a heat flux sensor including an insulating base, a first protective member disposed on one side of the insulating base, and a second protective member disposed on the back side of the insulating base has been proposed. . Specifically, in this heat flux sensor, a plurality of first and second via holes penetrating in the thickness direction are formed in the insulating base material, and the first and second via holes are made of different thermoelectric materials. First and second interlayer connection members are embedded. The plurality of first and second interlayer connection members are alternately connected in series by the first wiring pattern formed on the first protection member and the second wiring pattern formed on the second protection member. Yes. Note that the insulating base, the first protective member, and the second protective member are configured to include a thermoplastic resin.

  Such a heat flux sensor is manufactured as follows. That is, first, an insulating base material is prepared, and first and second via holes are formed in the insulating base material and filled with the first and second conductive pastes. The first and second conductive pastes constitute the first and second interlayer connection members by solid phase sintering.

  In addition, a first protective member on which the first wiring pattern is formed and a second protective member on which the second wiring pattern is formed are prepared. Then, the second protective member, the insulating base material, and the first protective member are sequentially laminated so that the first and second conductive pastes are in contact with the predetermined first wiring pattern and the predetermined second wiring pattern. Form.

  Thereafter, the laminate is pressed while being heated from the upper and lower surfaces in the laminating direction, so that the first and second conductive pastes are solid-phase sintered to form the first and second interlayer connection members. Integrate. Specifically, in the integration step, a heating step for forming the first and second interlayer connection members from the first and second conductive pastes and a cooling step for cooling after that are performed while appropriately changing the temperature and the applied pressure. Do.

  Here, for example, Patent Document 1 proposes a press device that includes a plurality of press machines having a pair of press plates and that can set the temperature and the pressure of the press plates in each press machine independently of each other. Yes. For this reason, an integration process can be performed using such a press apparatus. That is, the heating process is performed while placing the laminate on a press having a press plate set at the temperature of the heating process and pressurizing the laminate with a predetermined pressure. Further, the cooling step is performed while placing the laminate on another press having a press plate set at the temperature of the cooling step and pressurizing the laminate with a predetermined pressure. Therefore, as compared with the case where the heating process and the cooling process are performed with one press, there is no need for a standby time for raising or lowering the press plate, so that the manufacturing time can be shortened.

  In the heating step, the temperature of the press plate is set to a temperature higher than the glass transition temperature of the thermoplastic resin constituting the insulating substrate. Thereby, in a heating process, since a thermoplastic resin flows and pressurizes the 1st and 2nd conductive paste, solid phase sintering of the 1st and 2nd conductive paste can be performed favorably. In the cooling step, the temperature of the press plate is set to about room temperature.

JP 2009-290012 A

  However, as a result of studies by the present inventors, it was confirmed that bubbles were generated inside the heat flux sensor when the integration process was performed using the press device as described above.

  That is, since the heating process and the cooling process are performed using different press machines, the pressing force is once released when the heating process is performed and the press machine is changed. In this case, since the applied pressure is released while the thermoplastic resin is at a high temperature, bubbles are generated by generating gas from the thermoplastic resin. For this reason, if the cooling process which cools to room temperature at once in this state is performed, the thermoplastic resin will solidify with the presence of the bubbles, and the bubbles remain in the heat flux sensor.

  An object of this invention is to provide the manufacturing method of the heat flux sensor which can suppress that a bubble remain | survives inside in view of the said point.

  In order to achieve the above object, a heat flux sensor having a thermoelectric conversion element (40, 50), comprising a thermoplastic resin, and having a plurality of via holes penetrating in the thickness direction ( 11 and 12) are formed, and a conductive paste (41, 51) in which an organic solvent is added to an alloy powder in which a plurality of metal atoms maintain a predetermined crystal structure is filled in via holes is filled While preparing a base material (10) and arranging a first protective member (20) having a first wiring pattern (21) in contact with a predetermined conductive paste on one surface (10a) of an insulating base material A laminated body (70) is formed by disposing a second protective member (30) having a second wiring pattern (31) formed on the other surface (10b) of the insulating base material and in contact with a predetermined conductive paste. Do not heat the laminate. Pressurized insulating substrate from al stacking direction, the first protective member, and integrating the second protection member, is carried out. In the integration, the laminate is placed between the pair of main heating press plates (121), and the main body is pressed with the main heating press plate at the main heating temperature. By pressing, the thermoelectric conversion element, the first wiring pattern, and the second wiring pattern are electrically connected while forming the thermoelectric conversion element by solid-phase sintering the conductive paste while flowing the thermoplastic resin of the insulating base material. Main heating which is mechanically and mechanically connected, and after the main heating, a pre-cooling press in which a laminated body is arranged between a pair of pre-cooling press plates (131) and set to a pre-cooling temperature. The laminate is preliminarily cooled by pressurizing the laminate with a pressure for precooling with a plate, and after the precooling, the laminate is disposed between a pair of main cooling press plates (141). The main cooling temperature is lower than the preliminary cooling temperature. By pressurizing the laminated body with the main cooling press plate with the main cooling pressure, the main body of the laminated body is cooled and preliminarily cooled to change from the main heating press plate to the preliminary cooling press plate. The precooling temperature and the precooling pressure are set so that the bubbles (80) generated when the laminate is moved can be crushed.

  According to this, by pre-cooling, the temperature of the thermoplastic resin is lowered while crushing the bubbles. For this reason, it can suppress that a bubble remains in the inside of a heat flux sensor.

  Reference numerals in parentheses attached to each component and the like indicate an example of a correspondence relationship between the component and the like and specific components described in the embodiments described later.

It is a top view of the heat flux sensor in a 1st embodiment. It is sectional drawing along the II-II line | wire in FIG. It is sectional drawing which shows the manufacturing process of the heat flux sensor in 1st Embodiment. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3A. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3B. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3C. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3D. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3E. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3F. It is sectional drawing which shows the manufacturing process of the heat flux sensor following FIG. 3H. It is a flowchart which shows the integration process in 1st Embodiment. It is a figure which shows the case used in the case of an integration process. It is sectional drawing which shows the 1st preheating process and 2nd preheating process in an integration process. It is sectional drawing which shows the main heating process in an integration process. It is sectional drawing which shows the state which complete | finished this heating process and released the applied pressure. It is sectional drawing which shows the precooling process in an integration process. It is sectional drawing which shows this cooling process in an integration process. It is a figure which shows the experimental result which investigated the relationship between the applied pressure and temperature in a preliminary cooling process, and bubble generation | occurrence | production. It is sectional drawing of the heat flux sensor in other embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
A first embodiment will be described with reference to the drawings. First, the structure of the heat flux sensor 1 of this embodiment is demonstrated, referring FIG. 1 and FIG. In FIG. 1, a first protective member 20 described later is omitted.

  In the heat flux sensor 1, the insulating base material 10, the first protection member 20, and the second protection member 30 are integrated, and the first and second interlayer connection members 40 and 50 are alternately connected in series inside the integrated body. The structure is connected to In the present embodiment, the first and second interlayer connection members 40 and 50 correspond to thermoelectric conversion elements.

  The insulating base material 10 is in the form of a plate-like film that includes a thermoplastic resin having flexibility. A plurality of first via holes 11 and second via holes 12 penetrating in the thickness direction are alternately formed in the insulating base material 10. In this embodiment, the insulating base material 10 is configured by sequentially stacking thermoplastic polyimide, thermoplastic polyetherimide, and thermoplastic polyimide. The thermoplastic polyimide is a portion that functions as a fusion layer when bonded to the first and second protective members 20 and 30 and is formed extremely thin relative to the thermoplastic polyetherimide. For example, each thermoplastic polyimide has a thickness of about 25 μm, and the thermoplastic polyetherimide has a thickness of about 188 μm. That is, most of the insulating base material 10 is formed of thermoplastic polyetherimide.

  A first interlayer connection member 40 is disposed in the first via hole 11, and a second interlayer connection member 50 is embedded in the second via hole 12. That is, the first interlayer connection member 40 and the second interlayer connection member 50 are embedded in the insulating base material 10 so as to alternate.

  The first interlayer connection member 40 and the second interlayer connection member 50 are made of thermoelectric materials such as metals and semiconductors having different thermoelectric powers so as to exhibit the Seebeck effect. For example, in the first interlayer connecting member 40, the Bi (bismuth) -Sb (antimony) -Te (tellurium) alloy powder constituting the P-type maintains the crystal structure of a plurality of metal atoms before sintering. It is composed of a metal compound sintered in a solid phase. Further, for example, the second interlayer connection member 50 is a metal compound obtained by solid-phase sintering so that Bi-Te alloy powder constituting N-type maintains the crystal structure of a plurality of metal atoms before sintering. Composed.

  In FIG. 1, the first and second interlayer connection members 40 and 50 are hidden by a first wiring pattern 21 to be described later, but the positions of the first and second interlayer connection members 40 and 50 are shown for easy understanding. It is indicated by a broken line and hatched there.

  The 1st protection member 20 is made into the plate-shaped film shape comprised including the thermoplastic resin, and is arrange | positioned so that the one surface 10a of the insulating base material 10 may be covered. In the present embodiment, the first protective member 20 is configured by sequentially laminating thermoplastic polyimide, thermosetting polyimide, and thermoplastic polyimide.

  The first protective member 20 is formed with a plurality of first wiring patterns 21 in which a copper foil or the like is patterned on the side 20 a facing the insulating substrate 10. The plurality of first wiring patterns 21 are electrically connected to one end of the first interlayer connection member 40 and one end of the second interlayer connection member 50 adjacent thereto.

  The 2nd protection member 30 is made into the plate-shaped film shape comprised including the thermoplastic resin, and is arrange | positioned so that the other surface 10b of the insulating base material 10 may be covered. In the present embodiment, the second protective member 30 is configured by sequentially laminating thermoplastic polyimide, thermosetting polyimide, and thermoplastic polyimide.

  The second protective member 30 has a plurality of second wiring patterns 31 formed by patterning a copper foil or the like on the side 30 a facing the insulating substrate 10. The plurality of second wiring patterns 31 are electrically connected to the other end of the first interlayer connection member 40 and the other end of the second interlayer connection member 50 adjacent thereto.

  More specifically, the first wiring pattern 21 and the second wiring pattern 31 are formed so that the first interlayer connection member 40 and the second interlayer connection member 50 adjacent to each other are alternately folded and connected. Yes. That is, the first wiring pattern 21 and the second wiring pattern 31 are formed so that the first interlayer connection member 40 and the second interlayer connection member 50 are connected in series.

  In addition, although not particularly illustrated, a portion of the second wiring pattern 31 that is an end portion of the first and second interlayer connection members 40 and 50 connected in series is appropriately formed on the one surface 30a of the second protective member 30. The extended wiring is routed. The second protective member 30 has a contact hole that exposes the extended wiring in a cross section different from that shown in FIG. 2, and is electrically connected to the external wiring through the contact hole.

  The above is the configuration of the heat flux sensor 1 of the present embodiment. And when such a heat flux sensor 1 heat flux flows between one surface and the other surface in the thickness direction, one end of the first and second interlayer connecting members 40, 50 and the other A temperature difference occurs between the ends. At this time, in the heat flux sensor 1, a thermoelectromotive force is generated in the first and second interlayer connection members 40 and 50 by the Seebeck effect. For this reason, the heat flux sensor 1 outputs this thermoelectromotive force as a sensor signal (for example, a voltage signal).

  Next, a method for manufacturing the heat flux sensor 1 will be described with reference to FIGS. 3A to 3H. 3A to 3H are cross-sectional views corresponding to FIG.

  First, as shown in FIG. 3A, an insulating base material 10 is prepared, and a plurality of first via holes 11 are formed by a drill or the like. Then, as shown in FIG. 3B, each first via hole 11 is filled with a first conductive paste 41 constituting the first interlayer connection member 40. In this step, for example, the insulating base material 10 is disposed on the holding table (not shown) via the suction paper 60, and the first conductive paste 41 is filled in the first via hole 11 while the first conductive paste 41 is melted. To do. At this time, since the insulating base material 10 is disposed on the suction paper 60, most of the organic solvent of the first conductive paste 41 is absorbed by the suction paper, and the alloy powder is in close contact with the first via hole 11. Be placed.

  In the present embodiment, the first conductive paste 41 is a paste obtained by adding an organic solvent such as paraffin having a melting point of 43 ° C. to an alloy powder in which metal atoms maintain a predetermined crystal structure. Is used. Therefore, when the first conductive paste 41 is filled, the one surface 10a of the insulating base material 10 is heated to about 43 ° C. Moreover, as the powder of the alloy constituting the first conductive paste 41, for example, Bi—Sb—Te formed by mechanical alloy is used.

  Next, as shown in FIG. 3C, a plurality of second via holes 12 are formed in the insulating base material 10 by a drill or the like. As described above, the second via holes 12 are formed so as to alternate with the first via holes 11.

  Subsequently, as shown in FIG. 3D, each second via hole 12 is filled with a second conductive paste 51 constituting the second interlayer connection member 50. In this process, as in the process of FIG. 3B, for example, the insulating base material 10 is disposed on the holding table (not shown) via the suction paper 60, and the second conductive paste is melted while the second conductive paste is melted. The second conductive paste 51 is filled. As a result, most of the organic solvent of the second conductive paste 51 is adsorbed by the adsorbent paper, and the alloy powder is placed in close contact with the second via hole 12.

  In this embodiment, the second conductive paste 51 is an alloy powder in which metal atoms different from the metal atoms constituting the first conductive paste 41 maintain a predetermined crystal structure, and the melting point is normal temperature. A paste obtained by adding an organic solvent such as terpine is used. That is, as the organic solvent constituting the second conductive paste 51, a solvent having a lower melting point than the organic solvent constituting the first conductive paste 41 is used. And when filling the 2nd conductive paste 51, it is performed in the state by which one surface 10a of the insulating base material 10 was hold | maintained at normal temperature. In other words, the second conductive paste 51 is filled in a state where the organic solvent contained in the first conductive paste 41 is solidified. As a result, the second conductive paste 51 is prevented from entering the first via hole 11. Moreover, as the powder of the alloy constituting the second conductive paste 51, for example, Bi-Te formed by mechanical alloy is used.

  Then, in a step different from the above steps, as shown in FIG. 3E, one having a plurality of first wiring patterns 21 formed on one surface 20a of the first protective member 20 is prepared. Such a first protective member 20 is prepared, for example, by arranging a copper foil on one surface 20a of the first protective member 20 by thermocompression bonding or the like and patterning the copper foil.

  Similarly, as shown in FIG. 3F, one having a plurality of second wiring patterns 31 formed on one surface 30a of the second protective member 30 is prepared. Such a second protection member 30 is prepared by, for example, arranging a copper foil on one surface 30a of the second protection member 30 by thermocompression bonding and patterning the copper foil.

  Subsequently, as illustrated in FIG. 3G, the second protective member 30, the insulating base material 10, and the first protective member 20 are sequentially stacked to configure the stacked body 70. At this time, in the first protection member 20 and the second protection member 30, the first interlayer connection member 40 and the second interlayer connection member 50 are the first wiring pattern 21 and the second wiring pattern in the step of FIG. 31 to be connected in series. That is, the first protective member 20 and the second protective member 30 are arranged such that the first wiring pattern 21 and the second wiring pattern 31 are in contact with the predetermined first and second conductive pastes 41 and 51.

  Next, as illustrated in FIG. 3H, an integration process is performed in which the stacked body 70 is pressed and heated while being heated in a vacuum state from the upper and lower surfaces in the stacking direction.

  Below, the integration process of this embodiment is demonstrated concretely. In the present embodiment, in the integration process, as shown in FIG. 4, a first preheating process S10, a second preheating process S20, a main heating process S30, a precooling process S40, and a main cooling process S50 are performed. In this embodiment, when performing an integration process, the laminated body 70 is accommodated in the case 100 shown by FIG. 5, and it is set as the workpiece | work W, and the said workpiece | work W is arrange | positioned to a press apparatus.

  The case 100 of the present embodiment includes a base portion 101 and a cover portion 102, and the accommodation space 103 is configured by fitting the base portion 101 and the cover portion 102 together. Then, the stacked body 70 is accommodated in the accommodation space 103. Further, the case 100 is provided with an exhaust port 104, and the inside is decompressed by a vacuum pump (not shown) through the exhaust port 104. In addition, the case 100 of this embodiment is comprised using the stainless steel etc. which are excellent in heat conductivity, for example, and is comprised so that thermal resistance may become extremely small.

  The press apparatus of this embodiment is provided with the 1st-4th press machine 110-140, as FIG. 6A-FIG. 6D show. Moreover, the press apparatus can adjust the temperature and pressurizing force of the press plates 111 to 141 in the first to fourth press machines 110 to 140 independently of each other.

  And in an integration process, work W is conveyed in order to the 1st-4th press machines 110-140, the 1st preliminary heating process S10, the 2nd preliminary heating process S20, the main heating process S30, the preliminary cooling process S40, this Cooling process S50 is performed in order. In the present embodiment, as will be described later, both the first preheating step S10 and the second preheating step S20 are performed by the first press machine 110.

  Specifically, in the integration step, first, as shown in FIG. 6A, the workpiece W is disposed between the pair of press plates 111 in the first press machine 110, and the first preheating step S10 is performed. In the first preheating step S10, the workpiece W is pressurized at about 0.05 MPa for 10 minutes with a pair of press plates 111 set at 230 ° C. Thereby, in 1st preheating process S10, when it fills with the 1st, 2nd electroconductive pastes 41 and 51, the solvent which remained without adsorb | sucking to the adsorption paper 60 is dried.

  In the present embodiment, when the work W of the pair of press plates 111 is disposed, the buffer member 200 made of polyimide resin, Teflon (registered trademark), or the like is also disposed between each press plate 111 and the work W. To do. The buffer member 200 is very thin, for example, about 50 μm, and the thermal resistance is extremely small. As described above, the case 100 also has a very low thermal resistance. For this reason, when the workpiece W is pressurized with the pair of press plates 111, the temperature of the pair of press plates 111 and the temperature in the workpiece W become substantially equal. That is, when the workpiece W is pressurized with a pair of press plates 111 set at 230 ° C., the laminated body 70 becomes about 230 ° C. as with the press plate 111. In each of the following steps, the buffer member 200 is arranged as in the first preheating step S10. However, since the thermal resistance of the case 100 and the buffer member 200 is extremely small, the temperature of each press plate 112 to 114 And the temperature in the workpiece W are substantially equal.

  Next, the second preheating step S <b> 20 is performed while the workpiece W is placed on the first press machine 110. In the second preheating step S20, pressure is applied at about 8 MPa for 10 minutes while keeping the temperature of the pair of press plates 111 at 230 ° C. Thereby, in 2nd preheating process S20, the solid phase sintering of the 1st, 2nd conductive pastes 41 and 51 is started, and the connection with the 1st wiring pattern 21 and the 2nd wiring pattern 31 is started.

  Subsequently, as shown in FIG. 6B, the workpiece W is taken out from the first press machine 110, and the workpiece W is placed together with the buffer member 200 between the pair of press plates 121 in the second press machine 120, and this heating step S30. I do. In the main heating step S30, the workpiece W is pressurized at about 3.2 MPa for 15 minutes with a pair of press plates 121 set to 320 ° C. Thus, in the main heating step S30, the alloy powder in the first and second conductive pastes 41 and 51 is solid-phase sintered to form the first and second interlayer connection members 40 and 50. Moreover, in this heating process S30, the 1st, 2nd interlayer connection members 40 and 50, the 1st wiring pattern 21, and the 2nd wiring pattern 31 are electrically and mechanically connected. Furthermore, in this heating process S30, the insulating base material 10, the 1st protection member 20, and the 2nd protection member 30 are integrated.

  Moreover, in this heating process S30, it pressurizes with the press board 121 set to 320 degreeC, and the temperature in the workpiece | work W also becomes about 320 degreeC. Further, the glass transition temperature of the thermoplastic polyetherimide mainly constituting the insulating substrate 10 is 223 ° C. For this reason, in this heating process S30, the thermoplastic resin (namely, polyetherimide) which comprises the insulating base material 10 will be in the state which flowed. Thereby, in this heating process S30, since the fluidized thermoplastic resin also pressurizes the powder of the alloy in the 1st, 2nd electroconductive pastes 41 and 51, favorable solid-phase sintering can be performed. In the present embodiment, the press plate 121 corresponds to the main heating press plate, 320 ° C. corresponds to the main heating temperature, and 3.2 MPa corresponds to the main heating pressure.

  Next, as shown in FIG. 6C, the pressurization of the second press machine 120 is released. At this time, since the pressurization of the workpiece W is released at a high temperature of about 320 ° C., gas is generated from the flowing thermoplastic resin. For this reason, it will be in the state where the bubble 80 was generated inside the laminated body 70.

  Next, as illustrated in FIG. 6D, the workpiece W is disposed with the buffer member 200 between the pair of press plates 131 in the third press machine 130, and the preliminary cooling step S <b> 40 is performed. In the preliminary cooling step S40, the workpiece W is pressurized at 3.2 MPa for 15 minutes with a pair of press plates 131 set at 230 ° C. Thereby, the air bubbles 80 are crushed by pressurization, and are cooled to a temperature in the vicinity of the glass transition temperature of the insulating base material 10. In this embodiment, the press plate 131 corresponds to a precooling press plate, 230 ° C. corresponds to the precooling temperature, and 3.2 MPa corresponds to the precooling pressure.

  After that, as shown in FIG. 6E, the work W is taken out from the third press machine 130, and the work W is placed together with the buffer member 200 between the pair of press plates 141 in the fourth press machine 140 to perform the main cooling step S50. Do. Note that the temperature of the workpiece W is lower than that in the step of FIG. 6C. For this reason, when the pressurization of the third press machine 130 is released, gas is hardly generated from the thermoplastic resin constituting the insulating base material 10.

  In the main cooling step S50, the workpiece W is pressurized at 3.2 MPa for 8 minutes with a pair of press plates 141 set to 25 ° C. Thereby, in this cooling process S50, the laminated body 70 is cooled to about room temperature, and the heat flux sensor 1 is manufactured. At this time, in the main cooling step S50, the heat flux sensor 1 is cooled in a state where the bubbles 80 are crushed in the preliminary cooling step S40. For this reason, it is possible to suppress the bubbles 80 from remaining inside the heat flux sensor 1. In this embodiment, the press plate 141 corresponds to the main cooling press plate, 25 ° C. corresponds to the main cooling temperature, and 3.2 MPa corresponds to the main cooling pressure.

  The above is the manufacturing method of the heat flux sensor 1 in this embodiment. In addition, although the example which manufactures one heat flux sensor 1 was demonstrated here, the said process is performed, the several heat flux sensor 1 is manufactured integrally, and one heat flux sensor 1 is divided | segmented after that. May be manufactured.

  Here, the present inventors conducted further intensive studies on the relationship between the temperature and pressure in the preliminary cooling step S40 and the presence or absence of the bubbles 80, and obtained the experimental results shown in FIG. FIG. 7 shows the result when the buffer member 200 made of polyimide is disposed between the case 100 and each press plate 131 and the case 100 is made of stainless steel, as in FIG. 6D. For this reason, the temperature in FIG. 7 is a temperature set in the pair of press plates 131, but the inside of the workpiece W is also the same temperature.

  As shown in FIG. 7, in the preliminary cooling step S40, when the applied pressure is set to 4.2 MPa or more, the bubbles 80 remain by setting the temperature of the pair of press plates 131 in the range of 200 ° C. to 270 ° C. It is confirmed that it is not. Moreover, in precooling process S40, when the applied pressure is set to 3.7 MPa or more, it is confirmed that the bubbles 80 do not remain by setting the pressure in the range of 210 ° C. to 260 ° C. Furthermore, in precooling process S40, when the applied pressure is set to 3.2 MPa or more, it is confirmed that bubbles 80 are not generated by setting the pressure range to 225 ° C to 230 ° C.

  For this reason, in precooling process S40, if the relationship of the said pressurizing force and temperature is satisfy | filled, pressurizing force and temperature can be changed suitably.

  As described above, in this embodiment, after performing the main heating step S30, the preliminary cooling step S40 is performed, and the laminated body 70 is precooled while the bubbles 80 generated inside the heat flux sensor 1 are crushed. Yes. For this reason, when this cooling process S50 is performed, it can suppress that the bubble 80 remains inside.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be appropriately changed within the scope described in the claims.

  For example, in the said 1st Embodiment, the manufacturing method of the heat flux sensor 1 of the three-layer structure which has the 2nd protection member 30, the insulating base material 10, and the 1st protection member 20 was demonstrated. However, the manufacturing method of the heat flux sensor 1 of the first embodiment can be applied to a manufacturing method of the heat flux sensor 1 having a five-layer structure as shown in FIG. Specifically, the heat flux sensor 1 has a five-layer structure in which a second protective member 30, an insulating base material 10, a first protective member 20, an insulating base material 10, and a second protective member 30 are sequentially stacked. The insulating base material 10 and the second protection member 30 are symmetrically arranged with respect to the first protection member 20. That is, the one surface 10a of each insulating base material 10 is disposed so as to face the first protective member 20 side. Further, the first protective member 20 has the other-surface-side wiring pattern 22 formed on the other surface 20 b opposite to the one surface 20 a of the first protective member 20. More specifically, the other-surface-side wiring pattern 22 includes the first and second insulating base materials 10 positioned on the other surface 20b side together with the second wiring pattern 31 of the second protective member 30 positioned on the other-surface 20b side. Interlayer connection members 40 and 50 are formed to be connected in series.

  Such a heat flux sensor 1 is manufactured as follows. That is, two insulating base materials 10 are prepared in the steps of FIGS. 3A to 3D, and two second protective members 30 are prepared in the step of FIG. 3F. 3G, the second protective member 30, the insulating base member 10, the first protective member 20, the insulating base member 10, and the second protective member 30 are symmetric about the first protective member 20. Are sequentially stacked. Then, the heat flux sensor 1 shown in FIG. 8 is manufactured by performing the process of FIG. 3H.

  Such a heat flux sensor 1 includes two heat flux sensor units 1a and 1b. That is, the portion where the first and second interlayer connection members 40 and 50 formed on one insulating base material 10 are connected in series becomes the first heat flux sensor portion 1a, and is formed on the other insulating base material 10 A portion where the first and second interlayer connection members 40 and 50 are connected in series becomes the second heat flux sensor unit 1b. The first heat flux sensor unit 1a and the second heat flux sensor unit 1b are arranged to face each other.

  For this reason, when the heat flow passes through the heat flux sensor 1 in the thickness direction, the output signals output from the first heat flux sensor unit 1a and the second heat flux sensor unit 1b have opposite signs. Moreover, the influence of external temperature, etc. are equally added to the 1st heat flux sensor part 1a and the 2nd heat flux sensor part 1b. Therefore, by calculating the difference between the output signal from the first heat flux sensor unit 1a and the output signal from the second heat flux sensor unit 1b, a detection signal in which the influence of the external temperature is canceled can be obtained. As described above, such a heat flux sensor 1 can detect heat generation of a measurement object with high accuracy by being used in a measurement object that may generate heat, for example.

  Moreover, in the said 1st Embodiment, the insulating base material 10 may be comprised only with one type of thermoplastic resin, for example. Similarly, the 1st protection member 20 and the 2nd protection member 30 may be constituted only with one kind of thermoplastic resin. Furthermore, the first protective member 20 and the second protective member 30 may be made of a flexible insulating material other than a resin material, or may be made of an insulating material that does not have flexibility. Good.

  And in the said 1st Embodiment, the thermoplastic resin which comprises the insulating base material 10 can be changed suitably. In this case, in the precooling step S40, for example, the third press plate 131 is set to the glass transition temperature of the thermoplastic resin constituting the insulating base material 10, so that the bubbles 80 are crushed in the thermoplastic state. Since the resin can be solidified, the bubbles 80 can be prevented from remaining.

(Summary)
According to the first aspect shown in a part or all of the above-described embodiments, the heat flux sensor manufacturing method includes a thermoplastic resin, and includes a plurality of via holes penetrating in the thickness direction. An insulating substrate is prepared in which a conductive paste formed by adding an organic solvent to a powder of an alloy formed and having a plurality of metal atoms maintaining a predetermined crystal structure in a via hole is pasted. In the method of manufacturing the heat flux sensor, the first protective member having the first wiring pattern formed on one surface of the insulating base material and in contact with the predetermined conductive paste is disposed, and the predetermined surface is provided on the other surface of the insulating base material. A laminated body is formed by disposing a second protective member on which a second wiring pattern in contact with the conductive paste is formed. Further, in the method of manufacturing the heat flux sensor, the insulating base material, the first protective member, and the second protective member are integrated by applying pressure from the stacking direction while heating the stacked body. In the integration step, the laminated body is disposed between a pair of main heating press plates, and the laminate is pressed with the main heating press plate at the main heating temperature, whereby the insulating substrate is pressed. Electrically and mechanically connecting the thermoelectric conversion element to the first wiring pattern and the second wiring pattern while forming the thermoelectric conversion element by solid-phase sintering the conductive paste while flowing the thermoplastic resin material Do this book heating. In the integration step, after the main heating, the laminate is disposed between a pair of precooling press plates, and the precooling press plate having the precooling temperature is used to press the laminate with the precooling pressure. The laminated body is precooled by applying pressure. Further, in the integration step, after the preliminary cooling, the laminate is disposed between the pair of main cooling press plates, and the main body is pressed with the main cooling press plate having a lower main cooling temperature than the preliminary cooling temperature. The laminate is subjected to main cooling by pressurizing with a main cooling pressure. In the preliminary cooling, the preliminary cooling temperature and the preliminary cooling pressure are set so that bubbles generated when the laminate is moved from the main heating press plate to the preliminary cooling press plate can be crushed. Yes.

  Further, according to the second aspect, in the preliminary cooling, the preliminary cooling temperature is 200 ° C. or higher, 270 ° C. or lower, and the preliminary cooling pressure is 4.2 MPa or higher. According to this, the heat flux sensor is manufactured while suppressing the bubbles from remaining.

  Further, according to the third aspect, in the preliminary cooling, the preliminary cooling temperature is 210 ° C. or higher and 260 ° C. or lower, and the preliminary cooling pressure is 3.7 MPa or higher. According to this, the heat flux sensor is manufactured while suppressing the bubbles from remaining.

  According to the fourth aspect, in the preliminary cooling, the preliminary cooling temperature is 225 ° C. or higher and 230 ° C. or lower, and the preliminary cooling pressure is 3.2 MPa or higher. . According to this, the heat flux sensor is manufactured while suppressing the bubbles from remaining. Further, according to the fifth aspect, in the preliminary cooling, the preliminary cooling temperature is set to the glass transition temperature of the thermoplastic resin. According to this, the heat flux sensor is manufactured while suppressing the bubbles from remaining.

DESCRIPTION OF SYMBOLS 10 Insulation base material 11, 12 1st, 2nd via hole 20, 30 1st, 2nd protection member 21, 31 1st, 2nd wiring pattern 40, 50 1st, 2nd protection member (thermoelectric conversion element)
121 2nd press plate (press plate for main heating)
131 3rd press plate (press plate for pre-cooling)
141 4th press plate (main cooling press plate)

Claims (5)

A heat flux sensor having thermoelectric conversion elements (40, 50),
An alloy powder comprising a thermoplastic resin, in which a plurality of via holes (11, 12) penetrating in the thickness direction are formed, and a plurality of metal atoms maintain a predetermined crystal structure in the via holes. Preparing an insulating base material (10) filled with a conductive paste (41, 51) made into a paste by adding an organic solvent;
A first protective member (20) having a first wiring pattern (21) formed in contact with the predetermined conductive paste is disposed on one surface (10a) of the insulating substrate, and the other surface of the insulating substrate ( 10b) disposing a second protective member (30) having a second wiring pattern (31) in contact with the predetermined conductive paste to form a laminate (70);
Pressing the laminate from the laminating direction while heating the laminate, and integrating the insulating base, the first protective member, and the second protective member;
In the integration,
By placing the laminate between a pair of main heating press plates (121) and pressurizing the laminate with the main heating press plate with the main heating press plate having the main heating temperature, The thermoelectric conversion element, the first wiring pattern, and the second wiring pattern are formed by solid-phase sintering the conductive paste while flowing the thermoplastic resin of the insulating base material to form the thermoelectric conversion element. The main heating electrically and mechanically connected;
After the main heating, the laminate is disposed between a pair of precooling press plates (131), and the laminate is preliminarily pressurized with the precooling press plate having a precooling temperature. Pre-cooling the laminate by pressurizing with,
After the preliminary cooling, the main cooling press plate in which the laminated body is disposed between a pair of main cooling press plates (141) and has a main cooling temperature lower than the preliminary cooling temperature. The laminate is subjected to main cooling by pressurizing the laminate with a main cooling pressure, and
In the preliminary cooling, the preliminary cooling temperature and the preliminary cooling are performed so that bubbles (80) generated when the laminate is moved from the main heating press plate to the preliminary cooling press plate can be crushed. A method of manufacturing a heat flux sensor in which the applied pressure is set.   2. The heat flux sensor according to claim 1, wherein in the preliminary cooling, the preliminary cooling temperature is 200 ° C. or higher and 270 ° C. or lower, and the preliminary cooling pressure is 4.2 MPa or higher. Manufacturing method.   2. The heat flux sensor according to claim 1, wherein in the preliminary cooling, the preliminary cooling temperature is 210 ° C. or higher and 260 ° C. or lower, and the preliminary cooling pressure is 3.7 MPa or higher. Manufacturing method.   The heat flow according to claim 1, wherein in the preliminary cooling, the preliminary cooling temperature is 225 ° C or higher and 230 ° C or lower, and the preliminary cooling pressure is 3.2 MPa or higher. A manufacturing method of a bundle sensor.   The method of manufacturing a heat flux sensor according to claim 1, wherein in the preliminary cooling, the preliminary cooling temperature is set to a glass transition temperature of the thermoplastic resin.

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