JP2006156723A - Method for manufacturing thermally conductive substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermally conductive substrate in which voids are reduced by performing lamination in vacuum atmosphere thereby preventing entailment of air between a thermosetting resin composition and a lead frame. <P>SOLUTION: In the method for producing a thermally conductive substrate, a metal plate 14 for heat dissipation is applied to a thermally conductive sheet-like matter 6 of a soft thermosetting resin composition 1 and then a lead frame 2 is applied thereto in vacuum atmosphere. Subsequently, it is hot pressed in a formation die and subjected to primary curing while sustaining flexibility. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a heat conductive substrate (or a high heat dissipation substrate) using a mixture of a resin and an inorganic filler, which is used for a high power circuit in an electronic device.

  In recent years, with the demand for higher performance and miniaturization of electronic devices, higher density and higher functionality of semiconductors are required.

  As a result, the circuit boards on which they are mounted must also have a compact, high-density structure with excellent thermal conductivity and heat dissipation. As a result, the thermosetting resin is filled with an inorganic thermal conductive filler. A thermally conductive substrate in which the thermosetting composition thus obtained is integrated with a lead frame or a metal plate for heat dissipation has been proposed.

  A conventional method for manufacturing a thermally conductive substrate will be described with reference to a schematic manufacturing process diagram of FIG. That is, in FIG. 4, 1 is a soft thermosetting composition containing a thermosetting resin and a heat conductive filler as components. 2 is a lead frame having a plurality of through-holes 3 constituting wirings, electrodes or lead terminals, and the material thereof is a plate metal such as iron, copper, aluminum or alloys thereof having high thermal conductivity or high conductivity. The material is used. Reference numeral 4 denotes a terminal for connection or heat dissipation formed by bending a part of the lead frame 2.

  First, the heat conductive sheet 6 and the heat radiating metal plate 14 shown in FIG. 4A are prepared. As shown in FIG. Then, the film 12 is peeled off after being laminated so as not to sandwich air.

  Next, as shown in FIG. 4 (c), the heat conductive sheet 6 integrated with the heat radiating metal plate 14 is overlapped and laminated at a predetermined position of the lead frame 2.

  Then, as shown in FIG. 4D, the heat conductive sheet 6 integrated with the heat radiating metal plate 14 and the lead frame 2 are pressed by a forming die (not shown) to form a heat conductive sheet. A part of the object 6 is allowed to enter the through-hole 3 of the lead frame 2 and further heated at 170 ° C. for 6 hours to thermally cure the heat conductive sheet 6 to be integrated with the lead frame 2.

  Thereafter, as shown in FIG. 4E, unnecessary portions of the lead frame 2 are cut and removed, and the terminals 4 are formed by bending to complete the thermally conductive substrate 21.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2003-152148 A

  However, in the conventional method for manufacturing a thermally conductive substrate, when the thermosetting composition 1 is laminated on the lead frame 2 and thermally cured while being pressurized, the space between the thermally conductive sheet 6 and the lead frame 2 is reduced. However, there is a problem in that air is entrained and voids are generated, and the voids cause a decrease in thermal conductivity or a decrease in withstand voltage.

  Accordingly, an object of the present invention is to provide a method for producing a highly conductive thermally conductive substrate that does not generate voids.

  In order to achieve the above object, a method for producing a thermally conductive substrate of the present invention has the following configuration.

  The invention according to claim 1 of the present invention is a sheet-shaped soft thermosetting composition comprising a thermally conductive filler made of an inorganic material, a thermosetting resin, a curing agent and a curing accelerator as components. By laminating a metal plate for heat dissipation on one side of the heat conductive sheet-like material, laminated with a lead frame in a vacuum atmosphere, and heating and pressurizing in a forming mold to perform primary curing while having softness A lead frame, the heat-dissipating metal plate, and the thermosetting composition are integrated into a predetermined shape to form a preliminary heat conductive substrate, and after the preliminary heat conductive substrate is taken out of the forming mold, the heat A method for producing a thermally conductive substrate for curing a conductive sheet-like material. Since lamination is performed in a vacuum atmosphere, air does not get caught between the thermosetting composition and the lead frame, and heat with less voids. Conductive substrate Operational effects of being able fabricated to.

  According to a second aspect of the present invention, there is provided a heat-dissipating metal comprising a soft thermosetting composition comprising, as components, a thermally conductive filler made of an inorganic material, a thermosetting resin, a curing agent and a curing accelerator. 2. The method of manufacturing a thermally conductive substrate according to claim 1, wherein the sheet-like material coated on a plate is laminated with a lead frame in a vacuum atmosphere. Air does not get caught between the thermosetting composition and the lead frame, and there is an effect that a heat conductive substrate with few voids can be manufactured.

  In the invention according to claim 3 of the present invention, the metal plate for heat dissipation and the lead frame on which the thermosetting composition is laminated or applied are formed on a forming mold heated to 50 to 90 ° C. in advance. The heat-dissipating metal plate and the lead frame to which the thermosetting composition is laminated or applied are heated up to 50 to 90 ° C., and then pressed and integrated in the forming mold in a vacuum atmosphere The method for producing a thermally conductive substrate according to any one of claims 1 to 2, wherein the preliminary thermally conductive substrate is formed by heating to 100 ° C or higher after that, When the thermosetting composition becomes low viscosity at 50 to 90 ° C., the thermosetting composition flows to every corner by pressing and integrating in the forming mold to prevent unfilling. There is an effect of being able to.

  According to a fourth aspect of the present invention, after the preliminary heat conductive substrate is formed in the forming mold, the forming mold is cooled to 70 ° C. or lower, and then the preliminary heat conductive substrate is mounted. It takes out from the said metal mold | die, It is a manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-3, The said preliminary | backup heat conductive board | substrate in the said metal mold | die By cooling the substrate, the hardness of the preliminary heat conductive substrate is increased to make it difficult to be deformed when taken out.

  In the invention according to claim 5 of the present invention, the thermosetting composition is put into the forming mold heated in advance to 50 to 90 ° C., and the forming mold is preliminarily placed on the upper and lower heating plates. It is installed on a lower heating plate of a heat press set at a temperature of 50 to 90 ° C., the surroundings are in a vacuum atmosphere, and the temperature of the thermosetting composition is raised to 50 to 90 ° C. Heating and pressing is performed with the upper and lower heating plates being sandwiched, and the preliminary heating conductive substrate is formed by raising the temperature of the upper and lower heating plates to 100 ° C. or higher while being pressed in this state. 4. The method of manufacturing a thermally conductive substrate according to claim 3, wherein the temperature of the forming die is substantially the same as the set temperature of the lower heating plate of the hot press. It has the effect that it can be managed.

  According to a sixth aspect of the present invention, the thermosetting composition is put into the forming mold heated in advance to 50 to 90 ° C., and the forming mold is preliminarily placed on an upper and lower heating plate. It is installed on a lower heating plate of a heat press set at a temperature of 100 ° C. or higher, the surroundings are in a vacuum atmosphere, and the temperature of the thermosetting composition is raised to 50 to 90 ° C. The method for producing a thermally conductive substrate according to claim 3, wherein the preliminary thermally conductive substrate is formed by heating and pressing the sandwiched plate between upper and lower heating plates. Since the temperature of the hot press is raised by the lower hot platen of the hot press, it is necessary to actually measure the timing of pressurization in advance. To increase production efficiency without having to wait until the temperature rises It has the effect that kill.

  The invention according to claim 7 of the present invention is that the thermosetting composition of the preliminary thermal conductive substrate is cured in a constant temperature furnace after the preliminary thermal conductive substrate is taken out of the forming mold. 4. The method for producing a thermally conductive substrate according to claim 3, wherein the preliminary thermally conductive substrate in which the thermosetting composition is first cured while being soft and integrated into a predetermined shape is formed. The burrs of the thermosetting composition adhering to the forming mold can be made soft by taking out from the forming mold, and can be easily removed from the forming mold, and in addition, the thermosetting composition There exists an effect that a thing can be hardened certainly.

  The invention according to claim 8 of the present invention is characterized in that the preliminary thermal conductive substrate is left to cure in a constant temperature oven having an atmospheric temperature of 150 to 200 ° C. for 1 to 6 hours. It is a manufacturing method of the heat conductive board | substrate of description, and has the effect that the said preliminary | backup heat conductive board | substrate can be hardened reliably in the said thermostat.

  In the invention according to claim 9 of the present invention, the preliminary thermal conductive substrate is placed in a constant temperature furnace having an ambient temperature of room temperature, and is heated to 150 to 200 ° C. and then left to cure for 1 to 6 hours. 9. The method for producing a thermally conductive substrate according to claim 8, wherein the thermosetting composition is uniformly cured without applying unnecessary thermal stress when being placed in the constant temperature furnace. It has the effect of being able to do.

  According to the tenth aspect of the present invention, after the preliminary thermal conductive substrate is taken out of the forming mold, it is cured by heating in a state of being pressurized by a pressure oven, and then the preliminary thermal conductivity in a constant temperature furnace. The method for producing a thermally conductive substrate according to any one of claims 1 to 3, wherein the thermosetting composition of the substrate is cured, and the preliminary thermally conductive substrate is cured in a pressurized atmosphere. As a result, there is an effect that it is possible to suppress expansion and expansion of voids such as minute air latent in the heat conductive substrate.

  According to an eleventh aspect of the present invention, the thermosetting composition of the preliminary thermal conductive substrate is cured in a pressure oven after the preliminary thermal conductive substrate is taken out of the forming mold. It is a manufacturing method of the heat conductive board according to any one of claims 3 to 6, and the minute air which is latent in the heat conductive board by hardening the preliminary heat conductive board in a pressurized atmosphere, etc. It is possible to prevent the voids from expanding and expanding.

  According to a twelfth aspect of the present invention, the preliminary heat conductive substrate is disposed in a pressure oven without being constrained to at least the plane direction of the preliminary heat conductive substrate, and the heat conductive sheet-like material is arranged. The method for producing a thermally conductive substrate according to claim 11, wherein curing is performed without applying unnecessary stress to the entire surface of the thermosetting composition. Moreover, it has the effect that productivity can be improved by processing the preliminary | backup heat conductive board | substrate easily in large quantities in the said pressurization oven.

  Invention of Claim 13 of this invention is a manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-6 characterized by the vacuum atmosphere being 50000 Pa or less, By creating a vacuum atmosphere of this level, it is possible to prevent the generation of air layers and voids that significantly reduce the thermal conductivity and withstand voltage characteristics of commonly used substrates. This has the effect of improving productivity.

  According to the fourteenth aspect of the present invention, the thermosetting composition and the lead frame, which are put in a forming mold heated in advance to 50 to 90 ° C., are integrated with pressure in the forming mold. The method for producing a thermally conductive substrate according to any one of claims 1 to 6, wherein the thermosetting composition is not in contact in a vacuum atmosphere before being formed. And an effect of preventing air from being caught between the lead frame and the lead frame.

  The invention according to claim 15 of the present invention is characterized in that the preliminary heat conductive substrate is left to be cured in an atmosphere of 3 atm or more in a pressure oven at a temperature of 150 to 200 ° C. for 10 minutes or more. It is a manufacturing method of the heat conductive substrate of Claim 11, and has the effect that the said preliminary | backup heat conductive substrate can be hardened | cured completely reliably in the said pressurization oven.

  According to the sixteenth aspect of the present invention, the preliminary thermal conductive substrate is placed in a pressure oven having an atmospheric temperature of room temperature, and is heated to a temperature of 150 to 200 ° C. in an atmosphere of 3 atm or more. The method for producing a thermally conductive substrate according to claim 15, wherein the substrate is left to be cured for 10 minutes or longer, without applying unnecessary thermal stress when placed in the pressure oven. It has an effect that the conductive sheet can be uniformly cured without damage.

  In the invention according to claim 17 of the present invention, the temperature of the thermosetting composition is raised in a forming mold, and the melt viscosity of the thermosetting composition is reduced to 100 Pa · s or less, and then the pressure is applied. It is a manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-3 characterized by the above-mentioned, The said thermosetting composition removes the air of the surface of the said lead frame (or metal plate for heat dissipation). More reliably spread on the surface of the lead frame (or heat radiating metal plate) while removing, and as a result, improve the adhesion between the thermosetting composition and the lead frame (or heat radiating metal plate), and It has the effect of preventing unfilling.

  According to an eighteenth aspect of the present invention, the temperature of the thermosetting composition is increased in a forming mold, and the thermosetting composition is maintained at a temperature of 100 ° C. or higher for 30 seconds or longer to perform preliminary heat conduction. A method for producing a thermally conductive substrate according to any one of claims 1 to 3, wherein the conductive substrate is formed and then taken out from the forming mold. The preliminary heat conductive substrate is reliably formed, and it has an effect of facilitating the handling of the subsequent process.

  According to the nineteenth aspect of the present invention, the temperature of the thermosetting composition is raised in a forming mold so that the viscosity of the thermosetting composition is 1000 Pa · s or more and a preliminary heat conductive substrate is formed. 4. The method of manufacturing a thermally conductive substrate according to claim 1, wherein the preliminary thermal conduction has a predetermined shape, which is formed and then taken out from the forming mold. This has the effect of forming the conductive substrate more reliably and facilitating the handling of the subsequent process.

  According to a twentieth aspect of the present invention, the thermosetting composition includes a liquid thermosetting resin and a thermoplastic resin powder as components, and the thermoplastic resin powder is a liquid. The method for producing a thermally conductive substrate according to any one of claims 1 to 3, wherein a material that becomes solid by absorbing and swelling the liquid component is used. It can be reliably formed in a short time, can be taken out from the forming mold in a short time, and has the effect of increasing production efficiency.

  As described above, according to the present invention, a soft thermosetting composition containing, as components, a thermally conductive filler made of an inorganic material, a thermosetting resin, a curing agent, and a curing accelerator is used as a lead frame in a vacuum atmosphere. The lead frame and the thermosetting composition are integrated into a predetermined shape by laminating and first-curing the thermosetting composition laminated on the lead frame by heating and pressurizing with a forming mold while having softness. Forming a preliminary heat conductive substrate, taking out the preliminary heat conductive substrate from the forming mold, and then curing the thermosetting composition, in a vacuum atmosphere As a result of the lamination, the air does not get caught between the thermosetting composition and the lead frame, and it is possible to produce a heat conductive substrate with few voids.

  Hereinafter, the manufacturing method of the heat conductive board | substrate in embodiment of this invention is demonstrated using drawing. FIG. 1 is a production process diagram for explaining a method for producing a thermally conductive substrate in an embodiment of the present invention, FIG. 2 is a cross-sectional view showing the lamination of the thermosetting composition and a metal plate for heat dissipation, and FIG. FIG. 4 is a manufacturing process diagram for explaining a conventional method for manufacturing a heat conductive substrate. FIG.

  In addition, the same code | symbol is provided about the structural member demonstrated by the prior art, and detailed description is simplified.

  FIG. 1A shows a melt viscosity of 5 to 5 in a room temperature region (30 to 50 ° C.) containing an epoxy resin as a curable resin and an inorganic thermally conductive filler such as alumina, aluminum nitride, or silicon carbide. 100 Pa · s of the thermosetting composition 1 is applied by the MONO pump 5 so as to draw a single stroke on the metal plate 14 for heat dissipation.

  At this time, a plurality of rows are applied, but the length of the first row is short, and the amount of resin in this portion is adjusted.

  FIG. 1B shows a state after the applied thermosetting composition 1 is left for a certain period of time (24 hours at room temperature). The thermosetting composition 1 spreads in the form of a sheet on the heat-dissipating metal plate 14, and the thermosetting composition 1 can quickly spread to every corner at the time of pressurization, so that insufficient filling can be prevented. .

  Next, as shown in FIG. 1 (c), the lead frame 2 is laminated in a vacuum atmosphere (about 100 Torr) on the side surface of the thermosetting composition 1 opposite to the surface on which the metal plate for heat dissipation 14 is formed, It moves to the hardening process which hold | maintains the lead frame 2 or the metal plate 14 for heat dissipation, and heat-presses, and pressurizes the whole surface of the thermosetting composition 1 simultaneously via the metal plate 14 for heat dissipation, heating.

  Then, as shown in FIG.1 (d), a part of thermosetting composition 1 permeates into the through-hole 3 of the lead frame 2, and the resin in the thermosetting composition 1 is thermoset and thermoset. The composition 1, the lead frame 2, and the heat radiating metal plate 14 are integrated.

  Next, as shown in FIG. 1E, after completion of the curing step, unnecessary portions of the lead frame 2 are cut and removed, and terminals 4 for connection to external circuits are formed by bending, so that the electronic device is used. A predetermined thermally conductive substrate 21 constituting the large power circuit is formed. An electronic component or the like is mounted on the wiring pattern of the lead frame 2 of the heat conductive substrate 21 in a later process.

  The thermosetting composition 1 may be formed into a sheet shape by an extrusion molding method and laminated on the heat radiating metal plate 14 as shown in FIG.

  Further, the lead frame 2 used in the present invention shown in FIG. 2 is made of a conductive and thermally conductive metal plate made of, for example, iron, aluminum, silver, copper, or an alloy material thereof, and is used for mounting electronic components. And a terminal 4 for connection to an external circuit. At least one surface of the lead frame 2 (the upper surface side in FIG. 2) is roughened by etching, sandblasting, grinder or the like in order to improve adhesion to the thermosetting composition 1, and 4 terminals Is plated to prevent corrosion and improve solderability. The lead frame 2 is made of a highly conductive copper material to form a wiring pattern and transmit an electrical signal with high efficiency, thereby forming a heat conductive metal plate having particularly good electrical characteristics. can do.

  Reference numeral 14 denotes a heat radiating metal plate made of a metal material such as iron, copper, aluminum, or an alloy thereof having high thermal conductivity. The heat radiating metal plate 14 is laminated on the surface opposite to the surface of the thermosetting composition 1 on which the lead frame 2 is provided, and constitutes a thermally conductive substrate 21. Thereby, the heat conductivity and heat dissipation of the heat conductive substrate 21 can be further improved.

  In addition, at least one surface (the lower surface side in FIG. 2) of the heat radiating metal plate 14 is roughened by etching, sandblasting or grinder, and the roughened surface is brought into contact with the thermosetting composition 11. By doing so, a heat conductive metal plate with high adhesion strength of the heat radiating metal plate 14 can be configured.

  Next, the formation state will be specifically described with reference to FIG. In FIG. 3, reference numeral 1 denotes a thermosetting composition laminated and pasted or applied to the heat radiating metal plate 14, and 2 is a lead frame.

  7 is a steel forming die (lower die), and the lead frame 2 is placed at a predetermined position on the upper surface. The forming mold (lower mold) 7 includes a pin 10 floated by a spring 15. This pin 10 is in contact with the portion of the heat-dissipating metal plate 14 where the thermosetting composition 1 is not attached, and holds the thermosetting composition 14. A space between the thermosetting composition 1 and the lead frame 2 is retained. This prevents the thermosetting composition 14 and the lead frame 2 from coming into contact with each other in the air before entering the vacuum atmosphere.

  Reference numeral 8 denotes a steel forming die (upper die), which is floated from the forming die (lower die) 7 by a spring 9, and before being in a vacuum atmosphere, the thermosetting composition 14 and the lead frame in air. 2 is prevented from coming into contact with air.

  Reference numerals 16 and 17 respectively denote a hot platen (upper) and a hot platen (lower) in the hot press.

  The forming mold (lower mold) 7 and the forming mold (upper mold) 8 in FIG. 3 (a) have been heated to 70 ° C. in advance, and the lead frame 2 and the thermosetting composition 1 are laminated and pasted thereto. Alternatively, the applied heat radiating metal plate 14 is installed as shown in the figure. In this case, the lead frame 2 is heated to 70 ° C. within a few seconds after being placed on the forming die (lower die) 7, but the thermosetting composition 1 affixed or applied to the heat radiating metal plate 14 is placed at room temperature. In this case, it is necessary to measure in advance the time until the temperature is raised to 70 ° C. The reason why the pressure is applied is that the thermosetting composition 1 is desirably in a low viscosity state, and the viscosity is lowest in the range of 70 to 80 ° C. Moreover, if the temperature is raised to 70 ° C. before putting into the mold, the temperature control of the thermosetting composition 1 becomes easier.

  The forming mold set as shown in FIG. 3B is placed on a hot platen (lower) 17 of a hot press heated to 100 ° C. in advance. Thereafter, the vacuum chamber (upper and lower) 18 is closed via the packing 19, and the inside is brought into a vacuum state (about 100 Torr). During this time, the forming mold that was 70 ° C. in about 30 seconds gradually increases in temperature, and the internal thermosetting composition 1 reaches a temperature at which the viscosity becomes the lowest of 70 to 80 ° C. If the degree of vacuum is too high, air bubbles are also generated from the thermosetting composition 1, so that holes are formed and air is easily trapped when the vacuum is released. In addition, there is a method in which the heating plates (upper and lower) 16 and 17 of the hot press are set to 70 ° C. in advance, a forming mold is placed and a vacuum atmosphere is set, and then the temperature is raised to 100 ° C. However, it is difficult to increase the temperature.

  Next, as shown in FIG. 3C, the forming die is closed by closing the heat press, and the forming die is heated and pressurized to partially transfer the thermosetting composition 1 to the through hole 3 of the lead frame 2. It penetrates and becomes a preliminary heat conductive substrate having a shape in which the thermosetting composition 1 and the lead frame 2 are integrated. At this time, the vacuum state may be released after the forming mold is closed.

  Thereafter, the forming mold is cooled to 70 ° C. or less, and after the hardness of the thermosetting composition 1 is increased, the preliminary heat conductive substrate is taken out from the forming mold. At this time, when the cooling is insufficient and the thermosetting composition 1 has a low hardness, a part of the thermosetting composition 1 adheres to the forming mold when taking out and there is a dent on the surface of the preliminary heat conductive substrate. Care must be taken because it may occur. After taking out, the thermosetting composition 1 is left to stand in a predetermined temperature atmosphere such as a constant temperature furnace for a predetermined time to complete the curing of the thermosetting composition 1 (not shown).

  At this time, if the temperature is raised in a constant temperature furnace or the like, the fine voids in the preliminary thermal conductive substrate may expand due to thermal expansion before the resin of the thermosetting composition 1 reacts and cures. As a countermeasure, there is a method in which the preliminary heat conductive substrate is heated in a state in which fine voids are not thermally expanded by being placed in an atmosphere of 3 atm or higher, for example, 5 atm, which is higher than atmospheric pressure. In general, this process is performed using a furnace called a pressure oven that can pressurize and heat the inside of the furnace. There is a method in which the resin is cured in a short time within 1 hour in this furnace, and then the curing is completed by putting it in a constant temperature furnace for 1 hour or more. . However, it is desirable to operate the pressurized oven in as short a time as possible because the pressure oven is more expensive than the ordinary constant temperature furnace for its capacity. In the present embodiment, the furnace is heated from room temperature to 170 ° C. after being pressurized to 5 atm after being placed in a pressure oven. It took about 15 minutes to raise the temperature, and after heating at 170 ° C. for about 30 minutes, it was taken out. After that, when the temperature of the furnace was lowered to about 70 ° C., the substrate was put in and the temperature was raised while being pressurized, but no expansion of voids was observed. In other words, the starting temperature of curing can be increased up to a temperature at which the resin viscosity is lowered and the thermal expansion of the void occurs, but the stress applied to the substrate is smaller when heating is started from room temperature as in this embodiment. As a result, the strength at the interface between different materials on the substrate can be increased. Further, it is desirable that the arrangement state of the substrate in the furnace is a natural state that is not constrained in any direction so as not to apply excessive stress to the substrate.

  The thermosetting composition contains a liquid thermosetting resin and a thermoplastic resin powder as components, and the thermoplastic resin powder absorbs and swells the liquid component of the liquid thermosetting resin. By using a material that has a shape, the thermosetting resin component can be brought into a semi-cured state in a short time without being polymerized and cured over time, so that the preliminary heat conductive substrate can be reliably obtained in a short time. Since it can be formed and can be taken out from the forming mold in a short time, the production efficiency can be improved.

  According to the above manufacturing method, the thermosetting composition can be easily and reliably laminated on the lead frame of various patterns, and as a result, various types of thermally conductive substrates can be manufactured. There is an effect.

  The present invention comprises laminating a soft thermosetting composition comprising a thermally conductive filler made of an inorganic material, a thermosetting resin, a curing agent and a curing accelerator as components in a lead frame in a vacuum atmosphere, The thermosetting composition laminated on the lead frame is heated and pressed with a forming die and is first cured while having a softness so that the lead frame and the thermosetting composition are integrated into a predetermined shape and preheated. A method for producing a heat conductive substrate in which a conductive substrate is formed, the preliminary heat conductive substrate is taken out from the forming mold, and then the thermosetting composition is cured, and lamination is performed in a vacuum atmosphere. Therefore, air does not get caught between the thermosetting composition and the lead frame, and it is possible to produce a heat conductive substrate with few voids. It is useful as applications such as the manufacture method of the thermally conductive substrate, such as those used in the road.

(A)-(e) The perspective view and sectional drawing which show the manufacturing process of one embodiment of this invention Laminated cross section of the thermosetting composition and metal plate for heat dissipation (A)-(c) The block diagram which demonstrated the formation condition of the thermally conductive board | substrate concretely (A)-(e) Sectional drawing which shows the manufacturing process of the conventional heat conductive board | substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thermosetting composition 2 Lead frame 3 Through-hole 4 Terminal 5 Mono pump 6 Thermal conductive sheet-like material 7 Mold (lower mold)
8 Mold (Upper mold)
9 Spring 10 Pin 12 Film 13 Roller 14 Heat Dissipation Metal Plate 15 Spring 16 Heating Plate (Top)
17 Heating board (bottom)
18 Vacuum chamber 19 Packing 21 Thermally conductive substrate

Claims (20)

A heat-dissipating metal on one side of a sheet of heat-conductive sheet-like material comprising a heat-conductive filler composed of an inorganic material, a thermosetting resin, a curing agent and a curing accelerator as components. A laminate of plates is laminated with a lead frame in a vacuum atmosphere, and the lead frame, the heat-dissipating metal plate, and the thermosetting are heated and pressed in a forming mold and primarily cured while having a softness. A heat conductive substrate is formed by integrating a heat conductive composition into a predetermined shape to form a preliminary heat conductive substrate, and taking out the preliminary heat conductive substrate from the forming mold, and then curing the heat conductive sheet. Production method. A lead frame in a vacuum in which a heat-dissipating metal plate coated with a soft thermosetting composition containing inorganic conductive materials, thermosetting resin, curing agent and curing accelerator as components is applied. The method for manufacturing a thermally conductive substrate according to claim 1, wherein: The heat-dissipating metal plate and the lead frame to which the thermosetting composition is laminated or applied are put into a forming mold heated in advance to 50 to 90 ° C., and the thermosetting composition is laminated, Alternatively, the coated metal plate for heat dissipation and the lead frame are heated and integrated in the forming mold in a vacuum atmosphere after the temperature is raised to 50 to 90 ° C., and then heated to 100 ° C. or higher to A pre-heat conductive substrate is formed, The manufacturing method of the heat conductive substrate as described in any one of Claims 1-2 characterized by the above-mentioned. After the preliminary thermal conductive substrate is formed in the forming mold, the preliminary thermal conductive substrate is taken out of the forming mold after the forming mold is cooled to 70 ° C. or lower. The manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-3. The thermosetting composition is charged into the forming mold heated in advance to 50 to 90 ° C., and the forming mold is preliminarily heated at a temperature of the upper and lower heating plates set to 50 to 90 ° C. After the temperature of the thermosetting composition is raised to 50 to 90 ° C., it is sandwiched by the upper and lower heating plates of the hot press and heated and heated. 4. The heat conductive substrate according to claim 3, wherein the preliminary heat conductive substrate is formed by raising the temperature of the upper and lower heating plates to 100 ° C. or higher while applying pressure. Method. The thermosetting composition is charged into the forming mold heated in advance to 50 to 90 ° C., and the forming mold is preliminarily heated at a temperature of an upper and lower heating plate set to 100 ° C. or higher. Installed on a lower heating plate, the surroundings are in a vacuum atmosphere, and after the thermosetting composition has been heated to 50-90 ° C., it is heated and pressed by sandwiching it with the upper and lower heating plates of the hot press The method for manufacturing a thermally conductive substrate according to claim 3, wherein the preliminary thermally conductive substrate is formed. 4. The thermosetting composition of the preliminary thermal conductive substrate is cured in a constant temperature furnace after the preliminary thermal conductive substrate is taken out of the forming mold. 5. A method for manufacturing a thermally conductive substrate. The method for producing a thermally conductive substrate according to claim 7, wherein the preliminary thermally conductive substrate is left to cure in a constant temperature furnace having an atmospheric temperature of 150 to 200 ° C for 1 to 6 hours. 9. The heat according to claim 8, wherein the preliminary heat conductive substrate is placed in a constant temperature oven having an atmospheric temperature of room temperature, and is heated to 150 to 200 ° C. and then left to cure for 1 to 6 hours. A method for manufacturing a conductive substrate. Claims: After the preliminary heat conductive substrate is taken out of the forming mold, it is cured by heating in a state of being pressurized by a pressure oven, and then the thermosetting composition of the preliminary heat conductive substrate is cured in a constant temperature oven. The manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-3. The heat according to any one of claims 1 to 3, wherein after the preliminary heat conductive substrate is taken out of the forming mold, the thermosetting composition of the preliminary heat conductive substrate is cured in a pressure oven. A method for manufacturing a conductive substrate. The preliminary heat conductive substrate is placed in a pressure oven without being constrained to at least the plane direction of the preliminary heat conductive substrate, and the heat conductive sheet is cured. Of manufacturing a thermally conductive substrate. The method for producing a thermally conductive substrate according to claim 1, wherein the vacuum atmosphere is 50000 Pa or less. The thermosetting composition and the lead frame that have been put in a forming mold heated to 50 to 90 ° C. in advance contact each other in a vacuum atmosphere before being pressure-integrated in the forming mold. It is not carried out, The manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-6 characterized by the above-mentioned. 12. The heat conductive substrate according to claim 11, wherein the preliminary heat conductive substrate is cured by being left in a pressure oven at a temperature of 150 to 200 ° C. for 10 minutes or more in an atmosphere of 3 atm or more. Production method. The preliminary heat conductive substrate is placed in a pressure oven having an atmospheric temperature of room temperature, heated to a temperature of 150 to 200 ° C. in an atmosphere of 3 atmospheres or more, and then left to be cured for 10 minutes or more. A method for producing a thermally conductive substrate according to claim 15. The temperature of the thermosetting composition is increased in a mold for forming, and the melt viscosity of the thermosetting composition is set to 100 Pa · s or less, followed by pressurization. The manufacturing method of the heat conductive board | substrate as described in any one. The thermosetting composition is heated in a mold for forming, and the thermosetting composition is maintained at a temperature of 100 ° C. or higher for 30 seconds or more to form a preliminary heat conductive substrate, and then the mold for forming is formed. The method for producing a thermally conductive substrate according to claim 1, wherein the thermal conductive substrate is taken out from the substrate. The thermosetting composition is heated in a forming mold, the viscosity of the thermosetting composition is set to 1000 Pa · s or more to form a preliminary heat conductive substrate, and then taken out from the forming mold. The manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-3 characterized by these. The thermosetting composition contains a liquid thermosetting resin and a thermoplastic resin powder as components, and the thermoplastic resin powder absorbs and swells the liquid component of the liquid thermosetting resin. The manufacturing method of the heat conductive board | substrate as described in any one of Claims 1-3 which uses what becomes a shape.

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