JP2013229369A - Mold package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure good heat radiation performance of a heating element from a heat radiation surface of a mold resin even when the mold resin warps due to a linear expansion coefficient difference between the mold resin and a substrate in a mold package formed by integrally sealing the heating element and the substrate with the same mold resin.SOLUTION: A substrate 10 has a linear expansion coefficient smaller than that of a mold resin 50. In the mold resin 50, the substrate 10 is positioned closer to the side of a heat radiation surface 51 than to a center 52 in a thickness direction of the mold resin 50 that is arranged parallel to a board thickness direction of the substrate 10. When a virtual straight line, positioned at a center between both end parts 10a, 10b which face each other in the substrate 10 and extending in a direction parallel with plate surfaces 11, 12, is referred to as a substrate center line C1, an element mounting part 40 is positioned on the substrate center line C1 when viewed in a normal direction of the substrate 10.

Description

  The present invention relates to a mold package in which a heat generating element such as a power MOS and a substrate are integrally sealed with the same mold resin, and more particularly to an improvement in heat dissipation of the heat generating element from a heat radiating surface of the mold resin.

  Conventionally, a mold package has been proposed in which an insulating sheet is attached to a lead frame on which a power chip as a heating element is mounted, and this is sealed with a mold resin (for example, see Patent Document 1).

  In such a mold package, the outer surface of the mold resin is used as a heat radiating surface, and an external member is brought into contact with the heat radiating surface via an adhesive, heat radiating grease, etc. Is radiated from the heat radiation surface.

JP 2005-123495 A

  In contrast to the above-described conventional mold package, the present inventor is examining not only a heat generating element but also a mold package in which a substrate such as a ceramic wiring board is sealed with a mold resin integrally with a heat generating element. This is intended to reduce the size and simplification of the configuration including the substrate.

  However, in the case where the substrate is enclosed in the mold resin together with the heat generating element in this way, since the substrate made of ceramic or the like has a smaller linear expansion coefficient than the mold resin, the temperature of the mold resin decreases after sealing with the mold resin. There arises a problem that the substrate warps together with the mold resin.

  Specifically, in consideration of heat dissipation including the substrate, the substrate is usually on the heat radiation surface side in the mold resin from the center in the thickness direction of the mold resin parallel to the thickness direction of the substrate. It is set as the structure located in. If it does so, mold resin will warp so that the site | part with a large thickness of mold resin may pinch | shrink a board | substrate among mold resin from the linear expansion coefficient difference of a board | substrate and mold resin.

  That is, the mold resin is warped so as to protrude toward the portion of the mold resin where the thickness of the mold resin is small, that is, on the heat radiating surface side, across the substrate. At this time, the substrate warps in the same direction following the warping of the mold resin.

  Therefore, the occurrence of this warp partially increases the distance between the heat radiation surface connected to the external member in the mold resin and the surface of the external member. And in the part where the said distance became large, thickness, such as the said adhesive agent and heat radiation grease, will become large, and heat dissipation will fall. Therefore, if the heat generating element in the mold resin is located at a portion where the distance is increased, the heat dissipation of the heat generating element from the heat radiating surface becomes insufficient.

  The present invention has been made in view of the above problems, and in a mold package in which a heating element and a substrate are integrally sealed with the same mold resin, the mold resin is determined by the difference in linear expansion coefficient between the mold resin and the substrate. It is an object of the present invention to ensure good heat generation of the heat generating element from the heat radiating surface of the mold resin even if it is warped.

  In order to achieve the above object, the invention according to claim 1 is a plate-like substrate mounting in which a substrate is mounted on a plate-like substrate (10), a heating element (20, 21), and one surface (31). An element mounting portion (40) which is two-dimensionally arranged with respect to the portion (30) and the substrate mounting portion and has a heating element mounted on one surface (41), a substrate, a heating element, a substrate mounting portion, and an element A mold package comprising: a mold resin (50) that seals the mounting portion integrally and is a heat radiating surface (51) that is connected to an external member to radiate heat; It is what has.

  That is, the substrate has a smaller linear expansion coefficient than that of the mold resin, and the substrate is within the mold resin, on the side of the heat radiation surface from the center (52) in the thickness direction of the mold resin parallel to the plate thickness direction of the substrate. The virtual straight line that is located at the center between the opposite ends (10a to 10d) of the substrate and extends in the direction parallel to the plate surfaces (11, 12) is the substrate center line (C1). The element mounting portion is located on the center line of the substrate as viewed from the normal direction of the substrate.

  According to this, the substrate warps so that it protrudes toward the heat radiating surface with the position of the substrate center line as the top, and at the same time, the heat radiating surface of the mold resin also protrudes so as to become the top (53) at the position of the substrate center line. Warp. Therefore, when this mold package is connected to the external member (K1), the distance between the heat dissipation surface and the external member is minimized at the top of the heat dissipation surface. At this time, since the element mounting portion on which the heat generating element is mounted is located on the substrate center line, the element mounting portion is also present at a position corresponding to the top of the heat radiating surface.

  Therefore, according to the present invention, even if the mold resin is warped due to the difference in linear expansion coefficient between the mold resin and the substrate, the exothermic property of the heat generating element from the heat radiating surface of the mold resin can be ensured satisfactorily.

  Here, as in the invention described in claim 2, an imaginary straight line that is located at the center between the opposite end portions (50 a, 50 b) in the mold resin and extends in a direction parallel to the substrate center line ( When C2), it is preferable that the mold resin center line and the substrate center line are shifted from each other when viewed from the normal direction of the substrate.

  When viewed from the normal direction of the substrate, the center lines may coincide with each other and may be on the same straight line. However, in order to achieve such a configuration, there are large restrictions on the arrangement of the substrate and the heating element mounting portion. In that respect, if the configuration may be such that the center lines may be shifted from each other as in the present invention, the degree of freedom of arrangement of the substrate and the heating element mounting portion increases.

  Further, when there are a plurality of heat generating elements (20, 21) as in the invention described in claim 3, the heat generating element (21) having the largest physique generates the largest amount of heat. The element mounting portion on which the heat generating element is mounted is preferably positioned on the substrate center line in order to improve heat dissipation.

  Further, as in the invention described in claim 4, in addition to the element mounting portion located on the center line of the substrate, the heating elements (20, 21) mounted on the element mounting portion itself are also in the normal direction of the substrate. If it is located on the substrate center line as viewed from above, it is possible to expect further improvement in heat dissipation of the heating element mounted on the element mounting portion located on the substrate center line.

Further, in the invention described in claim 7, a plate-like substrate (10), a heating element (20, 21), and a plate-like substrate mounting portion (30) in which the substrate is mounted on one surface (31). The element mounting part (40) which is two-dimensionally arranged with respect to the board mounting part and on which the heating element is mounted on one surface (41) is integrated with the substrate, the heating element, the board mounting part, and the element mounting part. And a mold resin (50) having one surface connected to an external member and radiating heat to be a heat radiating surface (51), and a mold package comprising:
The substrate has a smaller linear expansion coefficient than that of the mold resin, and the substrate is located on the heat radiation surface side in the mold resin from the center (52) in the thickness direction of the mold resin parallel to the plate thickness direction of the substrate. An even number of heat generating elements are provided, and an even number of element mounting portions are provided according to the heat generating elements. When an imaginary straight line extending in a direction parallel to the planes (11, 12) is defined as the substrate center line (C1), the even number of element mounting portions are symmetrical with respect to the substrate center line as viewed from the normal direction of the substrate. (Refer to FIG. 14 and FIG. 15).

  According to this, the substrate warps so that it protrudes toward the heat radiating surface with the position of the substrate center line as the top, and at the same time, the heat radiating surface of the mold resin also protrudes so as to become the top (53) at the position of the substrate center line. Therefore, when this mold package is connected to the external member (K1), the distance between the heat dissipation surface and the external member is minimized at the top of the heat dissipation surface.

  At this time, since the even number of element mounting portions are positioned symmetrically with respect to the substrate center line, heat dissipation can be efficiently ensured for the entire even number of element mounting portions. Therefore, according to the present invention, even if the mold resin is warped due to the difference in linear expansion coefficient between the mold resin and the substrate, it is possible to ensure good exothermic properties of the heating elements from the heat dissipation surface of the mold resin.

  In addition, the code | symbol in the bracket | parenthesis of each means described in the claim and this column is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a figure which shows schematic plan structure of the mold package concerning 1st Embodiment of this invention. It is a figure which shows schematic sectional structure of the part of a board | substrate in the mold package shown by FIG. It is a figure which shows schematic sectional structure of the vicinity part of the heat generating element with the largest physique in the mold package shown by FIG. It is a schematic sectional drawing which shows the state which assembled | attached the mold package shown by FIG. 1 to the external member. It is a schematic plan view which shows the principal part of the mold package concerning 2nd Embodiment of this invention. It is a schematic plan view which shows the principal part of the mold package as a 1st preferable example in 2nd Embodiment. It is a schematic plan view which shows the principal part of the mold package as a 2nd preferable example in 2nd Embodiment. It is a schematic plan view which shows the principal part of the mold package as a 3rd preferable example in 2nd Embodiment. It is a schematic sectional drawing which shows the principal part of the mold package as a 4th preferable example in 2nd Embodiment. It is a schematic plan view which shows the principal part of the mold package as a 1st example of 3rd Embodiment of this invention. It is a schematic plan view which shows the principal part of the mold package as a 2nd example of 3rd Embodiment. It is a schematic plan view which shows the principal part of the mold package as a 1st example of 4th Embodiment of this invention. It is a schematic plan view which shows the principal part of the mold package as a 2nd example of 4th Embodiment. It is a schematic plan view which shows the principal part of the mold package as a 1st example of 5th Embodiment of this invention. It is a schematic plan view which shows the principal part of the mold package as a 2nd example of 5th 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 are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
The mold package S1 according to the first embodiment of the present invention will be described with reference to FIG. 1, FIG. 2, and FIG. In FIG. 1, the components inside the mold resin 50 are shown in a state where they pass through the mold resin 50. Further, in FIG. 3, the degree of warpage of each part associated with the mold resin 50 is deformed for easy understanding.

  The mold package S1 of the present embodiment is roughly divided into a plate-like substrate 10, heating elements 20, 21, a plate-like substrate mounting portion 30 having the substrate 10 mounted on one surface 31, and a substrate mounting portion 30. On the other hand, the element mounting portion 40, which is two-dimensionally arranged and has the heating elements 20 and 21 mounted on the one surface 41, and the substrate 10, the heating element 20, the substrate mounting portion 30, and the element mounting portion 40 are integrally sealed. In addition, the mold resin 50 is configured to be a heat radiating surface 51 that is connected to an external member and radiates heat.

  Here, the substrate 10 is made of a ceramic substrate made of ceramic such as alumina, or a resin substrate such as a printed substrate. Here, the wiring board is made of alumina ceramic. The substrate 10 may be a single layer substrate or a multilayer substrate.

  Here, the substrate 10 has a typical rectangular plate shape in which the front and back plate surfaces 11 and 12 are rectangular. Here, both end portions 10a and 10b facing each other in the longitudinal direction of the substrate 10 and both end portions 10c and 10d facing each other in the short direction of the substrate 10 are shown in FIG.

  The heating elements 20 and 21 are elements that generate a large amount of heat when driving a power MOS, IGBT, or the like. Here, the heating elements 20 and 21 are composed of a plurality of elements having different physiques, and the heating element 21 having the largest physique is the element that generates the largest amount of heat.

  The substrate mounting portion 30 has a rectangular plate shape that is slightly larger than the substrate 10. As shown in FIG. 2, the substrate 10 is in a state where one plate surface 12 faces the one surface 31 of the substrate mounting portion 30, and in this state, an adhesive 60 made of epoxy resin or the like is interposed therebetween. The substrate mounting part 30 is bonded and fixed.

  The element mounting portion 40 is provided with a plurality of elements having various plane sizes according to the physique of the heating elements 20 and 21. Each element mounting portion 40 is two-dimensionally arranged with respect to the substrate mounting portion 30 by being arranged outside the outer surface of the substrate mounting portion 30 in a direction parallel to the plate surfaces 11 and 12 of the substrate 10. ing.

  As shown in FIG. 3, each heating element 20, 21 is bonded and fixed on one surface 41 of the element mounting portion 40 via a die bonding material 61. The die bond material 61 is made of, for example, solder or a conductive adhesive.

  In the present embodiment, the substrate mounting part 30 and the element mounting part 40 are made of a conductive metal such as Cu or 42 alloy, and are configured as a part of a common lead frame. Of course, both of these 30 and 40 may be formed from separate members.

  Here, a suspension lead 32, which is a part of the lead frame, is connected to the substrate mounting portion 30. The element mounting portion 40 is integrally connected with a terminal 42 for electrical connection with the outside. The substrate 10 and the heating elements 20 and 21 are electrically connected by being connected by a bonding wire (not shown) in the mold resin 50.

  As shown in FIGS. 1 and 3, an insulating sheet 70 made of an electrically insulating material is attached to the other surface 43 of the element mounting portion 40 opposite to the one surface 41, which is also a mold resin. 50 is sealed. Here, the other surfaces 43 of the plurality of element mounting portions 40 are attached to one common insulating sheet 70.

  The insulating sheet 70 ensures electrical insulation between the element mounting portion 40 and the outside. Here, the element mounting portion 40 side is a layer made of an insulating material such as an epoxy resin, and the opposite side is a metal made of Cu. It consists of a laminated structure of two layers with layers attached. In addition, the insulating sheet 70 may be a single layer made of an insulating material such as an epoxy resin or a silicone resin, and is not particularly limited.

  The mold resin 50 is made of a typical mold material such as an epoxy resin. The mold resin 50 is obtained by mounting and fixing the substrate 10 and the heat generating elements 20 and 21 on the mounting portions 30 and 40, and then charging the mold resin into a mold (not shown) and filling the mold with the mold resin 50. Is molded by.

  Here, the mold resin 50 has a rectangular plate shape whose longitudinal direction is the longitudinal direction of the substrate 10. Here, FIG. 1 and FIG. 2 show both end portions 50a and 50b of the mold resin 50 which are separated in the longitudinal direction.

  In the present embodiment, a part of the substrate mounting part 30 and a part of the insulating sheet 70 are exposed from the mold resin 50 on the heat radiation surface 51 of the mold resin 50. Thereby, it is set as the structure which considered the heat dissipation of the board | substrate 10 and the heat generating elements 29 and 21. FIG. Specifically, the other surface 33 of the substrate mounting portion 30 and the surface opposite to the element mounting portion 40 side of the sheet 70 are exposed from the mold resin 50 in substantially the same plane as the heat radiating surface 51. Yes.

  Further, the tip of the terminal 42 connected to the element mounting portion 40 is exposed from the mold resin 50 on the side surface of the mold resin 50, here, the side surface along the long side of the mold resin 50. The terminal 42 is connected to the outside at the exposed portion.

  Here, the substrate 10 has a smaller linear expansion coefficient than the mold resin 50. For example, the substrate 10 is made of alumina ceramic and has a linear expansion coefficient of about 7 ppm / ° C., and the mold resin 50 is made of epoxy resin and has a linear expansion coefficient of about 14 ppm / ° C.

  Further, in the mold package S1, as shown in FIGS. 1 and 2, the thickness direction of the mold resin 50 and the thickness direction of the substrate 10 coincide with each other. Here, in FIG. 2, a center 52 in the thickness direction of the mold resin 50 parallel to the thickness direction of the substrate 10 is indicated by a virtual one-dot chain line 52. The substrate 10 is located in the mold resin 50 closer to the heat radiating surface 51 than the center 52 in the thickness direction of the mold resin 50.

  Further, as shown in FIG. 1, a substrate center line C1 is defined. The substrate center line C1 is an imaginary straight line C1 that is located at the center between the opposite ends 10a and 10b of the substrate 10 and extends in a direction parallel to the plate surfaces 11 and 12. Here, the substrate center line C <b> 1 is located at the center between both end portions 10 a and 10 b facing each other in the longitudinal direction of the planar rectangular substrate 10.

  As shown in FIG. 1, in the present embodiment, one element mounting portion 40 among the plurality of element mounting portions 40 is viewed from the normal direction of the substrate 10 (that is, the direction perpendicular to the paper of FIG. 1). And located on the substrate center line C1.

  In this case, in this embodiment, the substrate mounting part 30 and the element mounting part 40 are substantially on the same plane, but the substrate 10 and the element mounting part 40 are shifted in the thickness direction of the substrate 10. However, when viewed from the normal direction of the substrate 10, the element mounting portion 40 is located on the substrate center line C1.

  Here, the element mounting portion 40 located on the substrate center line C1 is one in which the heating element 21 having the largest physique among the plurality of heating elements 20 and 21 is mounted. In the present embodiment, the heating element 21 itself having the largest physique is also located on the substrate center line C <b> 1 when viewed from the normal direction of the substrate 10.

  Further, as shown in FIG. 1, a mold resin center line C2 is defined. The mold resin center line C2 is an imaginary straight line C2 that is located at the center between the opposite ends 50a and 50b of the mold resin 50 and extends in a direction parallel to the substrate center line C1. Here, the mold resin center line C2 is positioned at the center between both end portions 50a and 50b facing each other in the longitudinal direction of the planar rectangular mold resin 50.

  In this embodiment, as shown in FIG. 1, the mold resin center line C <b> 2 and the substrate center line C <b> 1 are shifted from each other when viewed from the normal direction of the substrate 10. Here, the center of the substrate 10 is configured to be offset toward one end 50a side (left side in FIG. 1) in the longitudinal direction of the mold resin 50.

  By the way, according to the present embodiment, the warping of the mold resin 50 is caused by the contraction of the mold resin 50 being restrained by the substrate 10 when the molded mold resin 50 is cooled as described above. The substrate 10 becomes a dominant factor of the warpage. And in this embodiment, the board | substrate 10 is located in the heat sink 51 side rather than the center 52 of the thickness direction of the mold resin 50 in the mold resin 50. FIG.

  Accordingly, the substrate 10 is warped so as to protrude toward the heat radiating surface 51 with the position of the substrate center line C1 as the top, and the heat radiating surface 51 of the mold resin 50 is also at the top 53 (see FIG. 2, see FIG. 3).

  Here, as shown in FIG. 4, the mold package S <b> 1 is attached to one surface K <b> 11 of an external member K <b> 1 made of a case, a heat sink, or the like. Specifically, the heat radiation surface 51 of the mold package S1 and the one surface K11 of the external member K1 are in contact with each other through a heat conductive material K2 such as a heat conductive adhesive or heat conductive grease in a state where heat conduction is possible. .

  At this time, if the warpage occurs in the mold package S1, when the mold package S1 is connected to the surface of the external member K1, as shown in FIG. The distance between the heat radiation surface 51 and one surface K11 of the external member K1 is the minimum distance L1.

  That is, the top 53 of the heat radiating surface 51 is a part where the heat conductive material K2 has the minimum thickness, and can be a part that is most excellent in heat radiation. Since the element mounting portion 40 on which the heat generating element 21 is mounted is located on the substrate center line C, the element mounting portion 40 is also present at a position corresponding to the top 53 of the heat radiating surface 51.

  Therefore, according to the present embodiment, even if the mold resin 50 is warped due to the difference in linear expansion coefficient between the mold resin 50 and the substrate 10, the heat generating property of the heating element 21 from the heat radiating surface 51 of the mold resin 50 is ensured satisfactorily. can do.

  In the present embodiment, as shown in FIG. 1, the mold resin center line C <b> 2 and the substrate center line C <b> 1 are shifted from each other when viewed from the normal direction of the substrate 10. Here, in the present embodiment, a configuration in which both the center lines C1 and C2 coincide with each other on the same straight line when viewed from the normal direction of the substrate 10 may be employed. However, in order to achieve such a configuration, there are large restrictions on the arrangement of the substrate 10 and the element mounting portion 40.

  In that respect, if the center lines C1 and C2 may be located at positions shifted from each other, the substrate 20 in the mold resin 50, the element mounting portion 40, the heating elements 20, 21 and the like, the mold resin 50 The degree of freedom of arrangement of the members to be sealed is increased.

  In the present embodiment, the element mounting portion 40 located on the substrate center line C1 is mounted with the heating element 21 having the largest physique among the plurality of heating elements 20 and 21. When there are a plurality of heating elements 20, 21, the heating element 21 having the largest physique generates the largest amount of heat, so the element mounting portion 40 on which the heating element 21 having the largest physique is mounted has the substrate center line C1. It is preferable to be positioned above for improving heat dissipation.

  Furthermore, in the present embodiment, in addition to the element mounting portion 40 located on the substrate center line C1, the heating element 21 itself mounted on the element mounting portion 40 also has the substrate center as viewed from the normal direction of the substrate 10. Located on line C1. For this reason, the heat dissipation element 21 can be expected to improve heat dissipation.

  In the case where there are a plurality of heating elements 20 and 21, the element mounting portion 40 on which the heating element 21 having the largest physique is mounted is not limited to being located on the substrate center line C1, but the physique is not limited. The non-maximum heating element 20 may be positioned on the substrate center line C1. Further, the heating element 20 that is located on the substrate center line C1 when viewed from the normal direction of the substrate 10 can also be configured as a heating element 20 that is not maximum in size.

  In the present embodiment, the substrate center line C1 is positioned at the center between both end portions 10a and 10b facing each other in the longitudinal direction of the substrate 10 having a rectangular plate shape. This is because the warpage in the longitudinal direction is likely to be larger than that in the short direction of the substrate 10, which is effective in applying each means of the above-described embodiment.

(Second Embodiment)
The second embodiment of the present invention will be described with reference to FIG. 5, focusing on the differences from the first embodiment. In the first embodiment, as shown in FIG. 1, in addition to the element mounting portion 40 located on the substrate center line C <b> 1, the heat generating element 21 itself mounted on the element mounting portion 40 also includes the substrate 10. It was the structure located on the board | substrate centerline C1 seeing from the normal line direction.

  On the other hand, as shown in FIG. 5, in this embodiment, the heating element 21 itself mounted on the element mounting portion 40 located on the substrate center line C <b> 1 is viewed from the normal direction of the substrate 10. The configuration is deviated from the center line C1. Even in such a case, since the heat of the heat generating element 21 is radiated through the element mounting portion 20, the same effect as described above due to the element mounting portion 40 being located on the substrate center line C1 is exhibited.

  Here, in the example shown in FIG. 5, both the substrate 10 and the insulating sheet 70 are rectangular, and on the extension lines (broken lines in FIG. 5) on both sides located at both ends 10 a and 10 b of the substrate 10, The corners of the insulating sheet 70 are located.

  The stress that the mold resin 50 receives is maximized at the outer periphery of the substrate 10. Therefore, when the corners of the insulating sheet 70 are positioned on the extended lines on both sides, which are the outline of the substrate 10 in this way, the insulating sheet 70 and the mold resin 50 are peeled off by the stress received by the mold resin 50, and around the insulating sheet 70. Resin cracks are likely to occur. Thereby, the insulating function by the insulating sheet 70 may be impaired.

  In view of such points, a preferred example of the present embodiment, which has been devised, will be described with reference to FIGS.

  6 to 8, the heating elements 20 and 21 and the element mounting portion 40 are omitted, but the arrangement of the element mounting portion 40 on the insulating sheet 70 is appropriately changed also in each mold package of the present embodiment. Thus, the element mounting portion 20 is similarly positioned on the substrate center line C1 when viewed from the normal direction of the substrate 10. Also in these, one of the heating elements 20 and 21 may be located on the substrate center line C1 or may not be located.

  In the first preferred example shown in FIG. 6, the insulating sheet 70 is shifted in the longitudinal direction of the substrate 10 from the position shown in FIG. 5 in the mold resin 50. Thereby, the position of the corner portion of the insulating sheet 70 is set to a position deviated from the extended lines (broken lines in FIG. 6) on both sides located at both end portions 10a and 10b of the substrate 10.

  In the second preferred example shown in FIG. 7, the planar size of the insulating sheet 70 is expanded in the longitudinal direction in the mold resin 50 as compared with that in FIG. 5. Thereby, the position of the corner portion of the insulating sheet 70 is set to a position deviated from the extended lines (broken lines in FIG. 7) on both sides located at both end portions 10 a and 10 b of the substrate 10.

  In the third preferred example shown in FIG. 8, the planar size of the insulating sheet 70 is reduced in the longitudinal direction in the mold resin 50 as compared with that in FIG. 5. Thereby, the position of the corner portion of the insulating sheet 70 is set to a position deviated from the extended lines (broken lines in FIG. 8) on both sides located at the both end portions 10 a and 10 b of the substrate 10.

  As described above, according to the configuration shown in FIGS. 6 to 8, the stress applied to the mold resin 50 at the corner portion of the insulating sheet 70 is smaller than that in the configuration of FIG. Can be suppressed. Thereby, it becomes easy to ensure the insulation function by the insulating sheet 70 appropriately.

  Furthermore, a fourth preferred example in the second embodiment will be described with reference to FIG. In this example, the position of the corner of the insulating sheet 70 in the mold resin 50 is set to a position deviated from the extension line of the plate surface 12 of the substrate 10.

  This is because, in the thickness direction of the substrate 10, the stress received by the mold resin 50 is maximum at the contact portions with the plate surfaces 11 and 12 of the substrate 10.

  If the corners of the insulating sheet 70 are positioned on the extension line of the plate surface 12 of the substrate 10, the same peeling and resin cracks as those described above are likely to occur, and the insulating function of the insulating sheet 70 may be impaired. In that respect, according to the example shown in FIG. 9, such a problem can be avoided.

(Third embodiment)
The third embodiment of the present invention will be described with reference to FIG. 10, focusing on the differences from the first embodiment. 10 and FIG. 11 to be described later, and FIG. 12 to FIG. 15 in each embodiment to be described later, only the mold resin 50, the substrate 10, the heating element 20, and the element mounting portion 40 are shown, and other components are omitted. It is.

  In the first embodiment, as shown in FIG. 1, the element mounting portion 40 and the heat generating elements 20, 21 are only on one side in the longitudinal direction of the substrate 10, specifically, only outside the end portion 10 d of the substrate 10. Had been placed.

  On the other hand, in the present embodiment, as shown in FIG. 10, the element mounting portion 40 and the heating element 20 are arranged on both outer sides in the longitudinal direction of the substrate 10, specifically, on the outer side and the end of the end portion 10 c of the substrate 10. Arranged outside the portion 10d.

  And in each of the said both sides, one of the element mounting parts 40 is located on the board | substrate centerline C1 seeing from the normal line direction of the board | substrate 10. FIG. Thereby, also in this embodiment, even if the mold resin 50 warps due to the difference in linear expansion coefficient, the heat generation property of the heating element 20 from the heat radiation surface 51 of the mold resin 50 can be ensured satisfactorily.

  In the first example shown in FIG. 10, the heating element 20 mounted on the element mounting portion 40 located on the substrate center line C <b> 1 on both outer sides in the longitudinal direction of the substrate 10 is also the method of the substrate 10. It is located on the substrate center line C1 when viewed from the line direction, improving heat dissipation.

  Here, also in the present embodiment, as shown in the second example shown in FIG. 11, both the outer heating elements 20 in the longitudinal direction of the substrate 10 are viewed from the normal direction of the substrate 10, and the substrate center line C <b> 1. You may employ | adopt the structure which remove | deviated from the top.

  Furthermore, although the heat generating element 20 itself is located on the substrate center line C1 on one of the outer sides in the longitudinal direction of the substrate 10, on the other hand, it may be configured to be located away from the substrate center line C1.

(Fourth embodiment)
A fourth embodiment of the present invention will be described with reference to FIG. 12, focusing on differences from the first embodiment.

  As shown in FIG. 12, the substrate center line in the substrate 10 having a rectangular plate shape is located at the center between both end portions 10 a and 10 b opposed in the longitudinal direction of the substrate 10 and is parallel to the plate surfaces 11 and 12. The first substrate center line C1, which is a virtual straight line extending in the direction, and the center between both ends 10c, 10d facing each other in the short direction of the substrate 10 and extending in a direction parallel to the plate surfaces 11, 12 There is a second substrate center line C3 that is a straight line.

  Therefore, in the present embodiment, the element mounting portion 20 is positioned on the first substrate center line C1 when viewed from the normal direction of the substrate 10 by using both the substrate center lines C1 and C3 orthogonal to each other. And a plurality of components including those positioned on the second substrate center line C3 when viewed from the normal direction of the substrate 10.

  According to this embodiment, not only the top 53 of the warpage of the mold resin 50 generated in the longitudinal direction in the rectangular plate-shaped substrate 10 but also the top of the warp of the mold resin 50 generated in the short direction is provided. 40 will be located. Therefore, the configuration is desirable in terms of improving the heat dissipation of the plurality of element mounting portions 40.

  Further, in the first example shown in FIG. 12, the heating elements 20 mounted on the element mounting portions 40 for all the element mounting portions 40 located on the substrate center lines C1 and C3 are also the same as the method of the substrate 10. It is located on the substrate center line C1 when viewed from the line direction, improving heat dissipation.

  Here, also in this embodiment, as shown in the second example shown in FIG. 13, the element mounting portions 40 are mounted on all the element mounting portions 40 located on the substrate center lines C <b> 1 and C <b> 3. A configuration may be employed in which the heat generating element 20 is out of the substrate center line C <b> 1 when viewed from the normal direction of the substrate 10.

  Furthermore, for some of the element mounting portions 40 located on the substrate center lines C1 and C3, the heating elements 20 themselves are also located on the substrate center lines C1 and C3. , C3 may be in a position deviating from C3.

  In the fourth embodiment, the element mounting portions 40 are arranged on both outer sides of the substrate 10 with the substrate center lines C1 and C3 interposed therebetween. However, the substrate center lines C1 and C3 are as shown in FIG. Alternatively, the element mounting portion 40 may be disposed only on one side of the substrate 10.

(Fifth embodiment)
A fifth embodiment of the present invention will be described with reference to FIG. In each of the above embodiments, the element mounting portion 40 is located on the substrate center lines C1 and C3 as viewed from the normal direction of the substrate 10. However, in this embodiment, the element mounting portion 40 is on the substrate center line C1. Provide a configuration that can ensure heat dissipation as much as possible even when there is not.

  The mold package of this embodiment is different from the mold package S1 shown in FIGS. 1 to 3 in that the arrangement of the heating element 20 around the substrate 10 and the element mounting portion 40 on which the heating element 20 is mounted is modified. This difference will be mainly described.

  As shown in FIG. 14, in the present embodiment, an even number of heating elements 20 having the same physique are provided, and an even number of element mounting portions 40 are provided according to the heating elements 20. Here, two element mounting portions 40 are provided outside each long side of the substrate 10 having a rectangular plate shape, and one heating element 20 is mounted on each element mounting portion 40.

  Then, on the outside of each long side of the substrate 10, when viewed from the normal direction of the substrate 10, the even number of element mounting portions 40 are arranged symmetrically about the substrate center line C <b> 1. Also in this embodiment, the substrate 10 is warped so as to protrude toward the heat radiating surface 51 with the position of the substrate center line C1 as the top, and the heat radiating surface 51 of the mold resin 50 is also at the top 53 at the position of the substrate center line C1. Warps in a convex shape so that

  Therefore, when this mold package is connected to the external member K1 in the same manner as described above, the distance between the heat dissipation surface 51 and the external member K1 is minimized at the top 53 of the heat dissipation surface 51. At this time, since the even number of element mounting portions 40 are positioned symmetrically with respect to the substrate center line C1, heat dissipation can be efficiently ensured for the entire even number of element mounting portions 40.

  Therefore, according to the present embodiment, even if the mold resin 50 is warped due to a difference in linear expansion coefficient between the mold resin 50 and the substrate 10, the heat generation property of the heating element 20 from the heat radiation surface 51 of the mold resin 50 is ensured satisfactorily. can do.

  Here, in the first example of FIG. 14, two element mounting portions 40 are provided outside each long side of the substrate 10, but as shown in the second example of FIG. Four element mounting portions 40 may be provided outside each of the ten long sides.

  Also in this example, since a total of eight element mounting portions 40 are positioned in line symmetry with respect to the substrate center line C1, heat dissipation can be efficiently ensured for the entire eight element mounting portions 40. Note that the even number of element mounting portions 40 may be positioned symmetrically with respect to the substrate center line C1, and the specific number of the even number is not particularly limited.

  Moreover, in this embodiment, if the said even number of heat generating elements 20 are all the same physique, it is thought that the heat dissipation effect by the said line symmetrical arrangement is large, However, The thing of a different physique may be contained. In this case, it is desirable that the heating element 20 having the largest physique is located closest to the substrate center line C1.

  Further, the fifth embodiment may also be configured using the two substrate center lines C1 and C3 shown in the fourth embodiment. That is, for each of the substrate center lines C1 and C3, an even number of heating elements 20 may be arranged symmetrically.

(Other embodiments)
In each of the above embodiments, the substrate 10 may be a resin substrate or the like other than the ceramic substrate as long as the linear expansion coefficient is smaller than that of the mold resin 50.

  In each of the above embodiments, the other surface 33 of the substrate mounting portion 30 and the insulating sheet 70 are exposed from the mold resin 50 at the heat dissipation surface 51 of the mold resin 50, and the heat dissipation of the substrate 10 and the heating elements 20 and 21 is performed. It was supposed to take into account gender. However, as long as the heat dissipation property is ensured, the entire substrate mounting portion 30 and insulating sheet 70 may be sealed with the mold resin 50.

  Further, the insulating sheet 70 may be omitted, and the other surface 43 of the element mounting portion 40 may be exposed from the mold resin 50 at the heat radiation surface 51 of the mold resin 50. In this case, when the mold package is attached to an external member, an electrically insulating sheet or an adhesive layer is provided on almost the entire heat dissipating surface 51, thereby allowing the heat dissipating surface 51 to be an external member. What is necessary is just to make it contact.

  In the third and fourth embodiments, the heat generating element 20 having the largest physique among the plurality of heat generating elements 20 is mounted on the element mounting portion 20 located on the substrate center lines C1 and C3. However, the present invention is not limited to this, and the heating element 20 having a physique that is not maximum may be mounted.

  Further, in the third to fifth and other embodiments, the mold resin center line C2 is not shown, but in these embodiments as well, if the degree of freedom of arrangement of the members in the mold resin 50 is taken into consideration, the substrate It is desirable that the mold resin center line C2 and the substrate center line C1 are shifted from each other when viewed from the normal direction of 10. Further, also in these embodiments, a configuration in which both the center lines C1 and C2 coincide with each other on the same straight line may be adopted.

  In addition to the combination of the above-described embodiments, the above-described embodiments may be appropriately combined within the possible range, and the above-described embodiments are not limited to the illustrated examples.

DESCRIPTION OF SYMBOLS 10 Board | substrate 11, 12 Plate | board surface of board | substrate 20, 21 Heat generating element 30 Board | substrate mounting part 40 Element mounting part 50 Mold resin 51 Mold heat dissipation surface 53 Center of thickness direction of mold resin C1 Board center line

Claims (7)

A plate-like substrate (10);
Heating elements (20, 21);
A plate-like substrate mounting portion (30) on which the substrate is mounted on one surface (31);
An element mounting portion (40) which is two-dimensionally arranged with respect to the substrate mounting portion and on which the heating element is mounted on one surface (41);
The mold resin (50) which integrally seals the substrate, the heating element, the substrate mounting portion, and the element mounting portion, and has one surface connected to an external member to dissipate heat. ) And
The substrate has a smaller linear expansion coefficient than the mold resin,
In the mold resin, the substrate is located closer to the heat radiation surface than the center (52) in the thickness direction of the mold resin parallel to the plate thickness direction of the substrate,
When a virtual straight line that is located at the center between the opposing ends (10a to 10d) and extends in a direction parallel to the plate surfaces (11, 12) is defined as a substrate center line (C1), the normal line of the substrate The mold package, wherein the element mounting portion is located on the substrate center line as viewed from the direction. When a virtual straight line extending in a direction parallel to the substrate center line and located at the center between the opposite end portions (50a, 50b) in the mold resin is defined as the mold resin center line (C2),
2. The mold package according to claim 1, wherein the mold resin center line and the substrate center line are shifted from each other when viewed from the normal direction of the substrate. A plurality of the heating elements are provided,
A plurality of the element mounting portions are provided corresponding to each of the heating elements,
The heating element (21) having the largest physique among the plurality of heating elements is mounted on the element mounting portion located on the center line of the substrate. Mold package.   In addition to the element mounting portion positioned on the substrate center line, the heating elements (20, 21) mounted on the element mounting portion themselves are also positioned on the substrate center line as viewed from the normal direction of the substrate. The mold package according to any one of claims 1 to 3, wherein the mold package is provided. The substrate is a rectangular plate,
The mold according to any one of claims 1 to 4, wherein the substrate center line is located at the center between both end portions (10a, 10b) facing each other in the longitudinal direction of the substrate. package. The substrate center line is a first substrate center line (C1) that is an imaginary straight line that is located in the center between both ends (10a, 10b) facing each other in the longitudinal direction of the substrate and extends in a direction parallel to the plate surface. And a second substrate center line (C3) which is an imaginary straight line located in the center between both ends (10c, 10d) facing in the short direction of the substrate and extending in a direction parallel to the plate surface. ,
The element mounting portion is positioned on the first substrate center line as viewed from the normal direction of the substrate, and is positioned on the second substrate center line as viewed from the normal direction of the substrate. The mold package according to claim 5, wherein the mold package comprises a plurality of items. A plate-like substrate (10);
Heating elements (20, 21);
A plate-like substrate mounting portion (30) on which the substrate is mounted on one surface (31);
An element mounting portion (40) which is two-dimensionally arranged with respect to the substrate mounting portion and on which the heating element is mounted on one surface (41);
The mold resin (50) which integrally seals the substrate, the heating element, the substrate mounting portion, and the element mounting portion, and has one surface connected to an external member to dissipate heat. ) And
The substrate has a smaller linear expansion coefficient than the mold resin,
In the mold resin, the substrate is located closer to the heat radiation surface than the center (52) in the thickness direction of the mold resin parallel to the plate thickness direction of the substrate,
An even number of the heating elements are provided,
The element mounting portion is also provided in an even number according to the heating element,
When a virtual straight line that is located at the center between opposite ends (10a, 10b) of the substrate and extends in a direction parallel to the plate surfaces (11, 12) is defined as a substrate center line (C1), the normal of the substrate As viewed from the direction, the even number of element mounting portions are arranged symmetrically about the substrate center line.

Images