JP6516212B2 - Substrate device and electronic device - Google Patents

Description

  The present invention relates to a substrate device and an electronic device using the substrate device.

  Conventionally, a substrate device on which an electronic component having a relatively large amount of heat generation is mounted is generally a substrate on which an electronic component is mounted on the surface, and includes a substrate having a conductive pattern and a heat dissipation pattern on the surface. The conductive pattern is a pattern for supplying power or an arbitrary signal to the electronic component. The heat radiation pattern is a pattern for radiating the heat generated in the electronic component. These patterns are formed of, for example, a heat conductive material such as copper foil. Furthermore, in the said board | substrate apparatus, in order to thermally radiate the heat which arose in the electronic component, there are some which are provided with the thermal pad. The heat dissipation pattern is configured to be thermally connected to the thermal pad (see, for example, Patent Document 1).

  In the substrate device, heat generated in the electronic component can be moved to the heat dissipation pattern through the thermal pad, so that the electronic component can be suppressed from becoming high in temperature.

JP, 2013-251337, A

  However, the conventional substrate device has a problem that the heat dissipation is not sufficient.

  Then, this invention aims at providing the board | substrate apparatus and electronic device which can improve heat dissipation.

  In order to achieve the above object, a substrate device according to one aspect of the present invention is a substrate for mounting an electronic component on the surface, and a conductive pattern electrically connected to the electronic component and a thermal of the electronic component The substrate has a heat dissipation pattern on the surface to dissipate heat, and the conductive pattern has a shape extending radially from the electronic component.

  The substrate device and the electronic device of the present invention can improve heat dissipation.

It is a perspective view which shows an example of the external appearance of the light projector in a comparative example. It is a perspective view which shows an example of the module in a comparative example. It is an upper surface view which shows an example of a structure of the board | substrate apparatus in a comparative example. It is sectional drawing which shows an example of a structure of the board | substrate apparatus in a comparative example. It is an upper surface view which shows an example of a structure of the electrically conductive pattern of the board | substrate apparatus in a comparative example, and a thermal radiation pattern. It is a figure which shows the result of having measured the temperature of the board | substrate apparatus in a comparative example. It is a figure which shows the result of having measured the temperature of the board | substrate apparatus in a comparative example. FIG. 2 is a top view showing an example of the configuration of a substrate device in accordance with Embodiment 1. FIG. 5 is a top view showing an example of the conductive pattern and the heat dissipation pattern of the substrate device in accordance with Embodiment 1. It is an enlarged view of the part of the ellipse A shown in FIG. It is a figure which shows the shape according to the expansion angle of the electrically conductive pattern and heat radiation pattern which temperature-measured. It is an external view which shows an example of a glass epoxy board. It is a graph which shows the measurement result of the temperature according to expansion angle in a glass epoxy board. It is a schematic diagram which shows typically the measurement result of the temperature according to expansion angle in a glass epoxy board. It is an external view which shows an example of Al board | substrate. It is a graph which shows the measurement result of the temperature by expansion angle in an Al board | substrate. It is a schematic diagram which shows typically the measurement result of the temperature by expansion angle in an Al board | substrate. FIG. 14 is a top view showing an example of the configuration of the conductive pattern and the heat dissipation pattern in the second embodiment. FIG. 18 is a top view showing an example of the configuration of a substrate device in Embodiment 2. FIG. 17 is a diagram showing an example of the configuration of the electronic component in the second embodiment.

<Findings that made the basis of the present invention>
[Configuration of illumination device provided with substrate device]
The substrate device mounted with the above-described electronic component (heat source) having a relatively large amount of heat generation is used, for example, for a lighting device or a semiconductor element. The illumination device is, for example, a light projector using a light emitting element such as an LED (Light Emitting Diode), a vehicle lamp, a ceiling light, or the like.

  Here, as a comparative example, a case where a substrate device is used for a light projector will be described.

  FIG. 1 is a perspective view showing an example of the appearance of a light projector in a comparative example. As shown in FIG. 1, the light projector 100 includes six LED modules 10, a frame 110 supporting the six LED modules 10, and an arm unit 120.

  The arm unit 120 is attached to the frame 110 and is a member for fixing the frame 110 to a ceiling or a floor surface. The arm unit 120 is integrally formed with a first arm unit 121 fixed to the frame 110 and a second arm unit 122 fixed to a ceiling or a floor surface or the like. A fixing portion 123 connected to the frame 110 using a screw or the like is provided at the tip of the first arm portion 121 (the tip on the opposite side to the second arm portion 122). The frame 110 and the arm portion 120 may be fixedly connected by the fixing portion 123 or may be connected so as to be rotatable to some extent. The second arm portion 122 is formed with a hole 124 for passing a screw or the like and an arc-shaped slit 125 centered on the hole 124. When the light projector 100 is screwed using the hole 124 in a rotatable state to some extent, the rotation range of the light projector 100 can be limited by passing a screw or the like through the slit 125.

[Configuration of LED Module (Electronic Device)]
The LED module 10 is an example of an electronic device provided with the substrate device 1.

  FIG. 2 is a perspective view showing an example of a module in a comparative example. As shown in FIG. 2, the LED module 10 includes the substrate device 1 in the comparative example, the heat sink 20, and the transparent cover 30. The substrate device 1 will be described later. As shown in FIG. 2, the heat sink 20 includes a base 21 and a plurality of heat radiation fins 22.

  The base 21 is a plate-like member whose surface shape is rectangular. In FIGS. 1 and 2, for the sake of explanation, an axis perpendicular to the surface of the base 21 is taken as a Z axis, and axes parallel to the surface of the base 21 are taken as an X axis and a Y axis. The X axis is parallel to two opposing sides of the rectangle, and the Y axis is parallel to the other two opposing sides of the rectangle. A plurality of substrate devices 1 are attached to the surface of the base 21.

  The plurality of heat radiation fins 22 are plate-like members here, and are attached to the back surface of the base 21 in a state where the front surface is parallel to the YZ plane. In other words, the radiation fin 22 extends from the base 21 to the negative side of the Z axis.

  The transparent cover 30 is a member that covers the substrate device 1, and is attached to the surface of the base 21.

[Configuration of substrate device]
The substrate device 1 is a device on which an LED chip as an example of an electronic component is mounted.

  FIG. 3 is a top view showing an example of the configuration of the substrate device 1 in the comparative example. FIG. 4 is a cross-sectional view showing an example of the configuration of the substrate device 1 in the comparative example.

  The substrate device 1 includes a substrate 11 on which the LED chip 12 and the thermal pad 13 are mounted, as shown in FIGS. 3 and 4.

  The LED chip 12 is an example of an electronic component, and here is a light emitting element. More specifically, the LED chip 12 is a flip chip provided with electrodes 12a and 12b on the back surface. The housing of the LED chip 12 has a rectangular shape on the surface. The LED chip 12 is fixed to the surface of the high thermal conductivity ceramic 17.

  The high thermal conductivity ceramic 17 is a substrate on which the LED chip 12 is mounted, and is mounted on the substrate 11. The high thermal conductivity ceramic 17 is a substrate having a rectangular shape on the surface, and in FIG. 3, the long side is disposed parallel to the Y axis, and the short side is disposed parallel to the X axis. Through holes 17 a and 17 b and interconnections 18 a and 18 b are formed in the high thermal conductivity ceramic 17.

  The through hole 17a has a structure in which a through hole formed in the high thermal conductivity ceramic 17 is filled with a conductive material, and electrically connects the wiring 18a and the current-carrying terminal 16a. Similarly, the through hole 17 b has a structure in which a through hole formed in the high thermal conductivity ceramic 17 is filled with a conductive material, and electrically connects the wiring 18 b and the current-carrying terminal 16 b.

  The wiring 18 a is a wiring that electrically connects the electrode 12 a on the anode side of the LED chip 12 and the through hole 17 a. The wiring 18a is a long film formed of a conductive material such as Al or Cu, one end thereof is located between the electrode 12a of the LED chip 12 and the high thermal conductivity ceramic 17, and the other end is a through hole It is placed in contact with 17a. The wiring 18 a is connected to the electrode 12 a on the anode side of the LED chip 12 by a bump 19 a.

  Similarly, the wiring 18 b is a wiring that electrically connects the electrode 12 b on the cathode side of the LED chip 12 and the through hole 17 b. The wiring 18b is a long film formed of a conductive material such as Al or Cu, one end thereof is located between the electrode 12b of the LED chip 12 and the high thermal conductivity ceramic 17, and the other end is a through hole It is placed in contact with 17b. The wiring 18 b is connected to the electrode 12 b on the anode side of the LED chip 12 by a bump 19 b.

  Two conductive terminals 16 a and 16 b are formed on the back surface of the high thermal conductivity ceramic 17.

  The conduction terminal 16 a is a terminal electrically connected to the electrode 12 a of the LED chip 12, and the conduction terminal 16 b is a terminal electrically connected to the electrode 12 b of the LED chip 12. The current-carrying terminals 16a and 16b are terminals having a rectangular shape on the surface, which are made of a conductive material such as Al or Cu. The current-carrying terminals 16 a and 16 b are arranged such that the long sides are along the long sides (sides parallel to the Y-axis) of the high thermal conductivity ceramic 17.

  The conduction terminal 16 a is electrically connected to the electrode 12 a on the anode side of the LED chip 12 through the through hole 17 a and the wiring 18 a. The conduction terminal 16 b is electrically connected to the electrode 12 b on the cathode side of the LED chip 12 through the through hole 17 b and the wiring 18 b.

  The thermal pad 13 is a member for transferring the heat generated in the LED chip 12 to the heat dissipation pattern 15, and is a sheet whose surface shape is a rectangular shape. The thermal pad 13 is disposed such that the surface is in contact with the back surface of the high thermal conductivity ceramic 17 and the back surface is in contact with the surface of the heat dissipation pattern 15 formed on the substrate 11. Furthermore, the thermal pad 13 is disposed between the current-carrying terminal 16a and the current-carrying terminal 16b, in a state of being electrically insulated from the current-carrying terminals 16a and 16b.

  The substrate 11 is a substrate on which the high thermal conductivity ceramic 17 on which the LED chip 12 is mounted is mounted. The substrate 11 is a plate-like member having a rectangular surface shape. Conductive patterns 14 a and 14 b and a heat dissipation pattern 15 are formed on the surface of the substrate 11.

  The conductive patterns 14a and 14b are patterns for supplying a voltage for lighting the LED mounted on the LED chip 12 to the current-carrying terminal 16a and the current-carrying terminal 16b. Further, the heat generated in the LED chip 12 is dissipated by the conductive patterns 14a and 14b through the current-carrying terminals 16a and 16b. The conductive patterns 14a and 14b are formed of, for example, a material having relatively high thermal conductivity and conductivity, such as copper foil.

  In the comparative example, the conductive patterns 14a and 14b are rectangular patterns. One end of the conductive pattern 14a is connected to the conduction terminal 16a, and the other end is disposed outside the conduction terminal 16a. One end of the conductive pattern 14b is connected to the conduction terminal 16b, and the other end is disposed outside the conduction terminal 16b.

  The heat radiation pattern 15 is a pattern for radiating the heat transmitted from the LED chip 12 to the thermal pad 13. The heat radiation pattern 15 has a shape obtained by cutting the above-described conductive patterns 14a and 14b from a rectangular pattern in top view, and is disposed in a state of being electrically insulated from the conductive patterns 14a and 14b. It is done. In other words, the conductive patterns 14a and 14b and the heat dissipation pattern 15 are provided independently and arranged at a constant interval.

  FIG. 5 is a top view showing an example of the configuration of the conductive patterns 14 a and 14 b and the heat dissipation pattern 15 of the substrate device 1 in the comparative example.

  As shown in FIG. 5, the substrate 11 in the comparative example is formed in a square shape with one side of 20 mm. Further, in FIG. 5, the distance between the conductive patterns 14 a and 14 b and the heat dissipation pattern 15 is 0.4 mm. Further, in FIG. 5, the width in the X-axis direction of the heat dissipation pattern 15 in the portion where the thermal pad 13 is disposed is 1.86 mm. In FIG. 5, the conductive patterns 14 a and 14 b have a length of 5.18 (2.59 × 2) mm in the Y-axis direction and a length of 8.76 ((20−1.86−0. It is 4 × 2) / 2) mm.

(Details of the issue)
Here, when a light emitting element such as the LED chip 12 described above or an electronic component having a very large amount of heat generation such as a semiconductor element is mounted, the substrate 11 described above has a problem that the heat dissipation effect is not sufficient. Furthermore, in the case of the substrate 11 on which an electronic component with a large amount of heat generation is mounted, there is a problem that the electronic component is thermally deteriorated since the heat radiation effect is not sufficient.

  Therefore, the inventors of the present invention measured the temperature of the substrate device 1 by causing the electronic component to actually generate heat in the substrate device 1 in the comparative example.

  6 and 7 are diagrams showing the results of measuring the temperature of the substrate device 1 in the comparative example. FIG. 6 is a measurement result of the entire surface of the substrate 11 of the LED module 10, and FIG. 7 is an enlarged view of a part of the measurement result of FIG.

  In FIGS. 6 and 7, in the LED chip 12 and the area in the vicinity thereof, the low luminance part (dark part) is the high temperature part, and the high luminance (light part) is the low temperature. It is a part.

  As can be seen from FIGS. 6 and 7, it can be seen that the range of the high temperature portion is larger on the conductive patterns 14 a and 14 b side (conductive terminal side) than the heat dissipation pattern 15 side of the LED chip 12. Conventionally, it is considered that the heat generated in the LED chip 12 is dissipated by the heat dissipation pattern 15 via the thermal pad, so the heat dissipation pattern 15 and the conductive patterns 14a and 14b are made to increase the area of the heat dissipation pattern 15 The shape of was determined. On the other hand, the present inventors acquired the knowledge that the heat dissipation on the side of the conductive patterns 14a and 14b was not sufficient, from the results of the temperature measurement.

  From FIG. 6, no difference in the distribution of the temperature difference is found among the plurality of LED chips 12, so that the cause of the temperature on the conductive patterns 14a and 14b side being higher than the heat radiation pattern 15 side is, for example, It is considered that this is not caused by manufacturing factors such as adhesion of copper foil forming the heat dissipation pattern 15 or the state of application of grease.

  Hereinafter, a substrate device and an electronic device according to an embodiment of the present invention will be described in detail with reference to the drawings. Each of the embodiments described below shows a preferable specific example of the present invention. Therefore, numerical values, shapes, materials, components, arrangements of components, connection configurations and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. Therefore, among the components in the following embodiments, components that are not described in the independent claims indicating the highest concept of the present invention are described as optional components.

  Further, each drawing is a schematic view, and is not necessarily illustrated exactly. Moreover, in each figure, the same code | symbol is attached | subjected about the same structural member.

Embodiment 1
The configuration of the substrate device of the first embodiment will be described with reference to FIGS. 1, 2, 4, and 8 to 17. In this embodiment, the case where a substrate device is used for a light projector will be described as an example. Moreover, the case where the LED chip as an example of an electronic component is mounted in a board | substrate apparatus is demonstrated to an example.

  Based on the above-described findings, the present inventors have considered that the shapes of the conductive patterns 14a and 14b are LED in consideration of the property that heat spreads radially in order to improve the heat dissipation of the conductive patterns 14a and 14b. It is set as the shape (that is, the shape which has a radially extending part) which spreads radially as it goes to the outer side from chip 12. FIG.

[1-1. Device configuration]
The configuration of a lighting device (light projector) equipped with an electronic device using a substrate device in the present embodiment will be described.

  The configuration of the projector is basically the same as the projector of the comparative example shown in FIG. As shown in FIG. 1, the projector 100 includes six LED modules 10, a frame 110 supporting the six LED modules 10, and an arm unit 120. The configurations of the frame 110 and the arm unit 120 are the same as in the comparative example.

  The LED module 10 is an example of an electronic device provided with the substrate device 1. As shown in FIG. 2, the LED module 10 includes the substrate device 1 according to the present embodiment, a heat sink 20, and a transparent cover 30. The configurations of the heat sink 20 and the transparent cover 30 are the same as in the comparative example.

[Configuration of substrate device]
The substrate device 1 is a device on which an LED chip as an example of an electronic component is mounted.

  FIG. 8 is a top view showing an example of the configuration of the substrate device 1 in the present embodiment. FIG. 9 is a top view showing an example of the conductive pattern and the heat dissipation pattern of the substrate device 1 in the present embodiment. FIG. 10 is an enlarged view of the portion of the ellipse A shown in FIG.

  As shown in FIGS. 8 and 9, the substrate device 1 includes a substrate 11 on which the LED chip 12 and the thermal pad 13 are mounted.

  Similar to the comparative example, the substrate 11 is a substrate for mounting the LED chip 12 on the surface, and the conductive patterns 14 a and 14 b and the heat dissipation pattern 15 are formed on the surface. The substrate 11 is a plate-like member having a rectangular surface shape. In the present embodiment, the LED chip 12 is mounted on the substrate 11 in a state of being mounted on the high thermal conductivity ceramic 17.

  The conductive patterns 14a and 14b are for the current-carrying terminal 16a electrically connected to the electrode 12a on the anode side of the LED chip 12 and the current-carrying terminal 16b electrically connected to the electrode 12b on the cathode side of the LED chip 12 , And a pattern for supplying a voltage for lighting the LED chip 12. Further, the heat generated in the LED chip 12 is dissipated by the conductive patterns 14a and 14b through the current-carrying terminals 16a and 16b. The conductive patterns 14a and 14b are formed of, for example, a material having relatively high thermal conductivity and conductivity, such as copper foil.

  The conductive patterns 14 a and 14 b have shapes extending radially from the LED chip 12. In the present embodiment, the conductive patterns 14a and 14b are patterns having an isosceles trapezoidal shape. The legs of the isosceles trapezoidal shape extend radially.

  In the conductive pattern 14a, the upper side and the lower side of the isosceles trapezoid are parallel to the long side of the conducting terminal 16a, and the upper side of the isosceles trapezoid is on the lower side of the conducting terminal 16a and the lower side is the outer periphery of the substrate 11. It is arranged to be located. The conductive pattern 14a is connected to the conducting terminal 16a in the vicinity of the upper side.

  Similarly, in the conductive pattern 14b, the upper and lower sides of the isosceles trapezoid are on the lower side of the conductive terminal 16b and the lower side is the substrate 11 so that the upper and lower sides of the isosceles trapezoid are parallel to the long side of the conductive terminal 16b. It is arrange | positioned so that it may be located in the outer peripheral side. The conductive pattern 14 b is connected to the conducting terminal 16 b in the vicinity of the upper side. The conductive patterns 14 a and 14 b are arranged in line symmetry with respect to an axis (not shown) parallel to the Y axis passing the center of the LED chip 12.

  The heat radiation pattern 15 is a pattern for radiating the heat transmitted from the LED chip 12 to the thermal pad 13. The heat radiation pattern 15 has a shape in which a portion corresponding to the above-described conductive patterns 14 a and 14 b and a region for insulation are cut away from a rectangular pattern in top view. In other words, the heat radiation pattern 15 arranges two isosceles trapezoids symmetrically with respect to an axis (not shown) parallel to the X axis passing the center of the LED chip 12, and has rectangular upper sides of the two isosceles trapezoids. It has a shape in which The length of the side (parallel to the X-axis) connecting the upper sides of the two isosceles trapezoidal rectangles is the same as the length of the upper side, and the sides parallel to the X-axis of the rectangle are arranged so as to overlap .

  The heat dissipation pattern 15 is disposed in a state of being electrically insulated from the conductive patterns 14a and 14b. That is, the conductive patterns 14a and 14b and the heat radiation pattern 15 are provided independently, and are disposed at a constant distance (for example, 0.4 mm or the like).

  Since it comprised in this way, the thermal radiation pattern 15 has a shape radially extended from LED chip 12 similarly to the conductive patterns 14a and 14b. The radially extending shape of the heat radiation pattern 15 and the radially extending shape of the conductive patterns 14a and 14b are the same and arranged in parallel. If the radially extending shape in the heat radiation pattern 15 and the radially extending shape in the conductive patterns 14a and 14b are formed in the same shape, the areas of the heat radiation pattern 15 and the conductive patterns 14a and 14b can be increased. It will be possible. Moreover, the area of the surface of the substrate 11 can be used more efficiently.

  Further, in the present embodiment, the heat dissipation pattern 15 is formed of the same material as the conductive patterns 14a and 14b. For example, if the conductive patterns 14a and 14b and the heat radiation pattern 15 are formed of copper foil, a simple process of forming the copper foil on the entire surface of the substrate 11 and peeling unnecessary areas (areas for separating the patterns). Can simultaneously form two types of patterns.

  The LED chip 12 is an example of an electronic component, and here is a light emitting element. The LED chip 12 is a flip chip provided with electrodes 12 a and 12 b on the back surface. The housing of the LED chip 12 has a rectangular shape (an example of a rectangular shape) on the surface. In addition, the shape of the housing | casing of LED chip 12 may not be a rectangular shape, but may be other shapes, such as square or a rhombus. The LED chip 12 is fixed to the surface of the high thermal conductivity ceramic 17. More specifically, as in the comparative example shown in FIG. 3, the wiring 18a formed on the surface of the high thermal conductivity ceramic 17 and the electrode 12a of the LED chip 12 are connected via the bumps 19a. The wiring 18 b formed on the surface of the high thermal conductivity ceramic 17 and the electrode 12 b of the LED chip 12 are connected via the bumps 19 b.

  The high thermal conductivity ceramic 17 is a substrate on which the LED chip 12 is mounted. In the present embodiment, the thickness of the high thermal conductivity ceramic 17 is 150 mm. The high thermal conductivity ceramic 17 is electrically connected to the through hole 17a for electrically connecting the wiring 18a formed on the surface and the conduction terminal 16a, and the wiring 18b formed on the surface and the conduction terminal 16b. And a through hole 17b for the purpose. The configurations of the through holes 17a and the through holes 17b are the same as in the comparative example. Two long conductive terminals 16a and 16b are formed on the back surface of the high thermal conductivity ceramic 17 under the through holes 17a and 17b.

  The conduction terminal 16 a is a terminal electrically connected to the electrode 12 a of the LED chip 12, and the conduction terminal 16 b is a terminal electrically connected to the electrode 12 b of the LED chip 12. The current-carrying terminals 16a and 16b are terminals having a rectangular shape on the surface, which are made of a conductive material such as Al or Cu. The current-carrying terminals 16a and 16b are arranged along the sides of the high thermal conductivity ceramic 17 parallel to the Y axis such that the longitudinal direction is parallel to the Y axis. As described above, the conduction terminal 16 a is electrically connected to the anode electrode 12 a of the LED chip 12, and the conduction terminal 16 b is electrically connected to the cathode electrode 12 b of the LED chip 12.

  In the present embodiment, the conductive terminals 16a and 16b have been described by taking as an example the case where the shape of the surface, that is, the shape of the plane parallel to the XY plane is rectangular (one example of a long shape). It may be other shapes such as a shape or a rounded rectangle.

  The thermal pad 13 is a member for transferring the heat generated in the LED chip 12 to the heat dissipation pattern 15, and is a sheet whose surface shape is a rectangular shape. The thermal pad 13 is disposed such that the surface is on the back surface of the high thermal conductivity ceramic 17 and the back surface is in contact with the surface of the heat dissipation pattern 15. Furthermore, the thermal pad 13 is disposed between the current-carrying terminal 16a and the current-carrying terminal 16b, in a state of being electrically insulated from the current-carrying terminals 16a and 16b.

  In addition, although the part corresponding to one LED chip 12 is illustrated in FIG. 8 and FIG. 9, the part corresponding to several LED chip 12 is shown in FIG. Although FIG. 8 and FIG. 9 show the case where the LED chips 12 are arranged independently, actually, it may be considered that a plurality of LED chips 12 are connected in series.

  FIG. 10 shows the case where the LED chips C1 and C2 are connected in series. In FIG. 10, the conductive pattern 14b connected to the cathode side electrode 12b of the LED chip C1 and the conductive pattern 14a connected to the anode side electrode 12a of the LED chip C2 are integrally formed. By this configuration, the cathode of the LED chip C1 and the anode of the LED chip C2 are connected.

  Thus, the conductive pattern may be integrally formed with other conductive patterns connected to the electrodes of the other LED chips.

[1-2. Details of conductive pattern and heat dissipation pattern]
As described above, the inventors of the present invention have the shape of the conductive patterns 14 a and 14 b radially spread outward from the LED chip 12 because the heat spreads radially. Furthermore, the inventors of the present invention measured the temperature of the substrate device 1 by sequentially changing the expansion angles of the conductive patterns 14a and 14b.

(Measurement condition)
FIG. 11 is a diagram showing the shapes of the conductive patterns 14 a and 14 b whose temperature was measured, according to the spread angle.

  Here, the spread angle is an angle between an axis X1 parallel to the X axis passing near the upper ends of the electrodes 12a and 12b and an isosceles trapezoidal leg of the conductive patterns 14a and 14b passing the axis X1. . In the present embodiment, since conductive patterns 14a and 14b have an isosceles shape, an angle between axis X1 and one leg of the trapezoid and an angle between axis X2 and the other leg of the trapezoid And is the same. The axis X2 is an axis parallel to the X axis passing near the lower ends of the electrodes 12a and 12b.

  FIG. 11 shows the case where the expansion angle is 30 degrees, 45 degrees, 60 degrees and 90 degrees. In the present embodiment, the temperature is measured by adding Reference (when the width of the conductive patterns 14a and 14b is wider than the comparative example) and the comparative example (0 deg) in the four cases shown in FIG. The

  Further, in the present embodiment, the temperature was measured for the case of using a glass epoxy substrate and the case of using a metal substrate (Al substrate).

  Furthermore, in the present embodiment, the ambient temperature was 30.0.degree.

(Measurement result)
FIG. 12 is an external view showing an example of a glass-epoxy substrate. FIG. 13 is a graph showing the measurement results of the temperature according to the spread angle in the glass epoxy substrate. FIG. 14: is a schematic diagram which shows typically the measurement result of the temperature according to the expansion angle in a glass epoxy board. In FIG. 14, the higher the region (brighter region) the higher the luminance, the higher the temperature.

  The glass epoxy substrate shown in FIG. 12 is a resin substrate and has a thickness of 0.9 mm and a thermal conductivity λ = 1.0 W / mK. In addition, the thickness 70 μm of the copper foil (conductive pattern and heat radiation pattern), the thickness of the grease (corresponding to the thermal pad 13) for radiating the heat of the LED chip 12 is equivalent to 50 μm, and the thermal conductivity λ is 1.3 W / It is mK. The calorific value Q was 1.45 W (equivalent to 418 mA).

  FIG. 15 is an external view showing an example of an Al substrate. FIG. 16 is a diagram showing the measurement results of the temperatures by expansion angle in the Al substrate. FIG. 17 is a schematic view schematically showing the measurement result of the temperature at each expansion angle in the Al substrate. In FIG. 17, as in the case of FIG. 14, the region with higher brightness (brighter region) is a region with higher temperature.

  The Al substrate shown in FIG. 15 is provided with an insulating layer which electrically insulates the Al substrate from the conductive pattern and the heat dissipation pattern. The thickness of the insulating layer is 0.1 mm, the thickness of the copper foil (conductive pattern and heat radiation pattern) 120 μm, the thickness of the thermal conductive sheet (thermal pad 13) is 1.5 mm, and the thermal conductivity λ is 4.5 W . The calorific value Q was 2.49 W (equivalent to 700 mA).

  Further, the LED chip 12 used in this measurement has a side (parallel to the Y axis) to which the conductive pattern is connected rather than the side to which the heat dissipation pattern 15 is connected (a side parallel to the X axis) Is longer.

  In FIG. 13 and FIG. 16, Tj indicates the temperature of the connection portion between the conductive pattern and the current-carrying terminal, and Ts indicates the temperature of the high thermal conductivity ceramic portion.

  In the case of the glass-epoxy substrate shown in FIG. 13, the temperature rise of Tj from the ambient temperature of 30.0 ° C. is 60 deg compared to 19.9 ° C. (49.9-30.0) of the comparative example (0 deg). Then, it is 17.2 ° C (47.2-30.0). That is, in the case of the glass epoxy substrate shown in FIG. 13, it can be seen that the temperature rise amount is suppressed by about 1.5 percent.

  Similarly, in the case of the Al substrate shown in FIG. 16, the temperature rise of Tj from the ambient temperature of 30.0 ° C. is 17.9 ° C. at 60 deg., While that of the comparative example (0 deg.) Is 18.7 ° C. is there. That is, in the case of the Al substrate shown in FIG. 16, it is understood that the temperature rise amount is suppressed by about 0.5%.

  In the case of the glass epoxy substrate shown in FIG. 13, the temperature rise of Tj from the ambient temperature of 30.0 ° C. is 19.5 ° C. and 19.9 ° C. at Reference and 0 deg, and the heat dissipation is hardly improved. . Similarly, in the case of the Al substrate shown in FIG. 16, the temperature rise of Tj from the ambient temperature of 30.0 ° C. is 18.5 ° C. and 18.7 ° C. at Reference and 0 deg, and the heat dissipation is almost improved. Absent. That is, in both of the two types of substrates, the improvement of the heat dissipation is hardly seen at Reference and 0 deg. Even if the width of the conductive patterns 14a and 14b is changed, the temperature rise amount does not change much, so that merely widening the heat outlet in the conductive patterns 14a and 14b does not provide a sufficient improvement in the heat dissipation. I understand.

  Furthermore, as shown in FIG. 13 and FIG. 16, in the case of any of the two types of substrates, when the expansion angle is 30 degrees, 45 degrees, and 60 degrees, the result is that the amount of temperature rise is suppressed. In particular, the amount of temperature rise is suppressed most at 60 degrees. In the case of 60 degrees, it turns out that the amount of temperature rise is controlled about 0.5 percent to 1.5 percent more than in the case of the comparative example. From the result of the temperature measurement, it can be understood that the degree of contribution of heat dissipation through the conductive pattern is high to some extent.

  That is, from the results of the temperature measurement shown in FIG. 13 and FIG. 16, it can be understood that the heat dissipation can be improved by forming the radially extending portions. This is considered to be because heat can be smoothly transferred by providing the conductive patterns 14 a and 14 b with the radially extending portions because heat is transferred radially.

  The heat dissipation is most improved at 60 degrees, but the length of the current-carrying terminal in the longitudinal direction (length of the side parallel to the Y-axis) is the width of the thermal pad 13 (longitudinal direction) It is considered that this is because the width in the crossing direction, for example, the length of the side parallel to the X axis) is longer. That is, when the length in the longitudinal direction of the current-carrying terminal is longer than the width of the thermal pad 13, the radiation angle is determined by determining the expansion angle of the conductive patterns 14a and 14b to be 45 degrees or more and less than 90 degrees. It is thought that the improvement effect will be further enhanced. In other words, when the length in the longitudinal direction of the current-carrying terminal is longer than the width of the thermal pad 13, the expansion angle of the conductive patterns 14 a and 14 b is determined to be larger than the expansion angle of the heat dissipation pattern 15. It is considered that the heat radiation improvement effect is further enhanced.

  Conversely, when the length in the longitudinal direction of the current-carrying terminal is shorter than the width of the thermal pad 13, the heat dissipation can be determined by determining the expansion angle of the conductive patterns 14a and 14b to an angle greater than 0 degree and 45 degrees or less. It is thought that the improvement effect of In other words, when the length in the longitudinal direction of the current-carrying terminal is shorter than the width of the thermal pad 13, the expansion angle of the heat dissipation pattern 15 connected to the thermal pad 13 is larger than the expansion angle of the conductive patterns 14a and 14b. It is thought that the heat radiation improvement effect is further enhanced by determining the angle.

  If the length in the longitudinal direction of the current-carrying terminal and the width of the thermal pad 13 are the same or if the difference is small, the heat dissipation can be sufficiently improved even if the expansion angle is designed to be approximately the same. it is conceivable that.

  The optimal expansion angle is considered to change depending on the size relationship between the length of the current-carrying terminal in the longitudinal direction and the width of the thermal pad 13 and the difference between them, the heat dissipation of the thermal pad 13 etc. Do. The optimum expansion angle may be determined in consideration of not only these conditions but also other conditions.

  Although the length in the longitudinal direction (Y-axis direction) of the current-carrying terminal is compared with the width (length in the X-axis direction) of the thermal pad in the above, this corresponds to the outlet of heat following the conductive patterns 14a and 14b. It corresponds to comparing the size (length or area) with the size of the outlet of heat following the heat dissipation pattern 15. For this reason, the longitudinal direction of the current-carrying terminal and the width direction of the thermal pad do not have to be orthogonal to each other, as long as they intersect with each other. The expansion angle of each pattern is determined so that the expansion angle of the pattern on the side where the size of the heat outlet is larger is larger than the expansion angle of the pattern on the side where the heat outlet is smaller.

  As shown in FIG. 13 and FIG. 16, when the expansion angle is 90 degrees (when the conductive patterns 14a and 14b do not have a radially extending shape), the temperature of the heat dissipation pattern is higher than the temperature of the conductive pattern Also, it can be seen that the heat dissipation on the heat dissipation pattern side is impaired. For this reason, the expansion angle is preferably an angle smaller than 90 degrees.

[1-3. Effect etc]
In the present embodiment, by configuring the conductive patterns 14 a and 14 b to have a shape that radially extends from the LED chip 12, the heat dissipation in the conductive patterns 14 a and 14 b is improved.

  Since heat is considered to diffuse radially, it is considered that heat transfer can be smoothly performed by configuring the conductive pattern and the heat radiation pattern to have a shape extending radially from the electronic component. This makes it possible to improve the heat dissipation of the conductive pattern.

  The above-mentioned temperature measurement is performed in a state in which the brightness of the LED mounted on the LED chip 12 is lower than that in actual use, and the calorific value is about half of the calorific value in the actual use state ing. Therefore, it is considered that in the actual use mode, an effect twice as high as the measurement result shown in FIG. 13 and FIG. 16 can be obtained. In fact, when the amount of heat generation in the actual use state was measured for the temperature rise of the glass epoxy substrate, the substrate device 1 of the present embodiment had a temperature of about 4.4 ° C. as compared to the case of using the substrate device in the comparative example. The amount of increase was suppressed.

  The expansion angle is preferably determined so that the heat is in an equilibrium state (in FIGS. 14 and 17, the area of the same temperature is circular). As described above, the heat dissipation in each pattern is considered to change depending on the heat conductivity of the thermal pad 13, the ratio of the length in the longitudinal direction of the current-carrying terminal to the width of the thermal pad 13, and the like. Therefore, the expansion angles of the conductive patterns 14a and 14b and the heat radiation pattern 15 may be set in consideration of these conditions.

  In the case of FIG. 14 and FIG. 17, when the expansion angle of the conductive patterns 14a and 14b is 60 degrees, the area of the same temperature is arc-shaped (doughnut-shaped) (FIG. 14 and FIG. e), it is preferable to determine the expansion angle of the conductive pattern to 60 degrees. On the other hand, for example, when the ratio of the length of the conductive terminal to the width of the thermal pad is larger, the spread angle of the conductive pattern may be determined to be a larger angle. The conductive terminal to the width of the thermal pad If the ratio of lengths is smaller, the spread angle of the conductive pattern may be determined to be a smaller angle.

  Further, as shown in FIG. 14 and (f) of FIG. 17, when the expansion angle of the conductive pattern is 90 degrees (when it does not have a radial shape), the heat dissipation on the heat dissipation pattern side may be impaired. For this reason, it is preferable to determine the expansion angle to an angle smaller than 90 degrees.

  In the present embodiment, the heat dissipation of the conductive patterns 14a and 14b can be improved by a simple change such as changing the shapes of the conductive patterns 14a and 14b in comparison with the comparative example. Since the substrate device 1 of the present embodiment does not require a separate member for improving heat dissipation or other complicated steps, it is possible to prevent an increase in manufacturing cost.

  Furthermore, in the present embodiment, the heat dissipation pattern 15 is configured to have a shape extending radially from the LED chip 12. Since the heat radiation pattern 15 has a shape extending radially from the LED chip 12, the heat transfer is smoothly performed. For this reason, although the area of the heat radiation pattern 15 of the present embodiment is reduced as compared with the comparative example, the heat radiation performance can be prevented from being impaired.

  When the length in the longitudinal direction of the current-carrying terminals 16 a and 16 b is larger than the width of the thermal pad 13, the expansion angle of the conductive patterns 14 a and 14 b is determined to be larger than the expansion angle of the heat dissipation pattern 15. When the length in the longitudinal direction of the current-carrying terminals 16 a and 16 b is smaller than the width of the thermal pad 13, the expansion angle of the conductive patterns 14 a and 14 b is determined to be smaller than the expansion angle of the heat dissipation pattern 15. That is, if the expansion angle on the large side of the heat outlet is increased, the heat transfer can be smoothed, and the heat state can be brought close to the equilibrium state.

  In the present embodiment, since the plurality of conductive patterns 14 a and 14 b are provided, a desired voltage can be supplied to the electronic component, and to the LED mounted on the LED chip 12 in the present embodiment.

  The substrate 11 is useful for an electronic component having a large amount of heat generation, such as a semiconductor element or a light emitting element, because the heat dissipation property is improved. By the improvement of the heat dissipation, deterioration of the semiconductor element or the light emitting element can be reduced.

  Since the LED module 10 has the thermal pad 13, the heat can be smoothly transferred from the electronic component to the heat dissipation pattern 15.

  The LED module 10 according to the present embodiment includes the substrate 11 described above and a heat sink (heat dissipating fin). Thereby, the heat dissipation of LED module 10 can be improved and degradation of an electronic component can be reduced.

Second Embodiment
The configuration of the substrate device of the second embodiment will be described with reference to FIGS. 1, 2 and 18 to 20. In the present embodiment, the case where the shapes of the conductive pattern 14 b and the heat dissipation pattern 15 are different from those of the first embodiment will be described.

  More specifically, the conductive pattern 14b and the heat dissipation pattern 15 of the present embodiment are integrally formed.

[2-1. Device configuration]
The substrate device 1 of the present embodiment is applied to the projector 100 shown in FIG. 1 as in the first embodiment. As shown in FIG. 1, the projector 100 includes six LED modules 10, a frame 110 supporting the six LED modules 10, and an arm unit 120. The configurations of the frame 110 and the arm unit 120 are the same as in the first embodiment.

  The LED module 10 is an example of an electronic device provided with the substrate device 1. As shown in FIG. 2, the LED module 10 includes the substrate device 1 according to the present embodiment, a heat sink 20, and a transparent cover 30. The configurations of the heat sink 20 and the transparent cover 30 are the same as in the first embodiment.

  The substrate device 1 is a device on which an LED chip as an example of an electronic component is mounted.

  FIG. 18 is a top view showing an example of the configuration of conductive patterns 14 a and 14 b and heat dissipation pattern 15 in the present embodiment. FIG. 19 is a top view showing an example of the configuration of the substrate device in the present embodiment. FIG. 20 is a diagram showing an example of the configuration of the LED chip 12 in the present embodiment. (A) of FIG. 20 is a top view, (b) is a cross-sectional view of a plane parallel to the XZ plane in the BB line portion of (a), (c) is an XY in the CC line portion of (b) It is the sectional view which looked at the section parallel to a plane from the Z-axis negative side.

  As shown in FIGS. 18 to 20, the substrate device 1 includes a substrate 11 and an LED chip 12.

  As in the first embodiment, the substrate 11 is a substrate for mounting the LED chip 12 on the surface, and the conductive patterns 14 a and 14 b and the heat dissipation pattern 15 are formed on the surface. The substrate 11 is a plate-like member having a rectangular surface shape.

  The conductive pattern 14a is a pattern for supplying a voltage for lighting the LED chip 12 to the current-carrying terminal 16a electrically connected to the electrode 12a on the anode side of the LED chip 12, as in the first embodiment. Moreover, the heat which generate | occur | produced in LED chip 12 is thermally radiated via the electricity supply terminal 16a by the electrically conductive pattern 14a. As in the first embodiment, the conductive pattern 14 a is formed of a material having relatively high thermal conductivity and conductivity, for example, copper foil.

  The conductive pattern 14 a has a shape that radially extends from the LED chip 12. The conductive pattern 14a is a pattern having an isosceles trapezoidal shape, as in the first embodiment. The legs of the isosceles trapezoidal shape extend radially. In the conductive pattern 14a, the upper side and the lower side of the isosceles trapezoid are parallel to the long side of the conducting terminal 16a, and the upper side of the isosceles trapezoid is on the lower side of the conducting terminal 16a and the lower side is the outer periphery of the substrate 11. It is arranged to be located. The conductive pattern 14a is connected to the conducting terminal 16a in the vicinity of the upper side.

  The conductive pattern 14 b and the heat dissipation pattern 15 are integrally formed in the present embodiment. In addition, the composite pattern which consists of the conductive pattern 14b and the thermal radiation pattern 15 is electrically separated from the conductive pattern 14a. Specifically, the conductive pattern 14a and the composite pattern are disposed at an inseparable interval. The composite pattern has a shape in which a portion corresponding to the conductive pattern 14a and a region for insulation are cut out from a rectangle. The composite pattern receives the heat generated in the LED chip 12 through the conduction terminal 16 b connected to the electrode 12 b on the cathode side of the LED chip 12 and the thermal pad 13 and dissipates the heat. Furthermore, the composite pattern supplies a voltage for lighting the LED chip 12 to the current-carrying terminal 16b. The composite pattern is formed of a material having relatively high thermal and electrical conductivity, such as copper foil.

  Also in the present embodiment, the conductive pattern 14a and the composite pattern are formed of the same material.

  In the present embodiment, as shown in FIG. 20, the LED chip 12 includes an electrode 12 a and an electrode 12 b, two LEDs 12 c, a lead frame 12 d, a sealing portion 12 e, and a resin substrate 12 f.

  The electrode 12a and the electrode 12b are formed of a conductive material such as metal. The electrode 12a is connected to the conductive pattern 14a, and the electrode 12b is connected to the conductive pattern 14b (heat dissipation pattern 15). The two LEDs 12c are disposed at the inner bottom of a recess formed substantially in the center of the resin substrate 12f and sealed by a sealing portion 12e made of a transparent material.

  The lead frame 12d functions as a thermal pad. Since the lead frame 12 d is a lead frame in which the electrode 12 b which is a cathode electrode and the thermal pad are integrally formed, it is not necessary to provide an insulating portion between the conductive pattern 14 b and the heat dissipation pattern 15. In other words, the conductive pattern 14 b and the heat dissipation pattern 15 can be integrally formed.

  In FIG. 20B, the heat transferred from the lead frame 12d to the heat radiation pattern 15 is the heat transferred from the electrode 12a of the LED chip 12 to the conductive pattern 14a and the heat transferred from the electrode 12b to the conductive pattern 14b. Too big. Further, the amount of heat transferred from the electrode 12 b to the conductive pattern 14 b is larger than the amount of heat transferred from the electrode 12 a to the conductive pattern 14 a. Therefore, in the present embodiment, not the conductive pattern 14a connected to the electrode 12a which is the anode electrode, but the conductive pattern 14b connected to the electrode 12b of the LED chip 12 is integrally formed with the heat dissipation pattern 15.

  In other words, the conductive pattern connected to the side where the amount of heat dissipation from the heat dissipation source (the LED chip 12) is large is integrally formed with the heat dissipation pattern 15. In the present embodiment, since the heat dissipation amount on the cathode side is larger than the heat dissipation amount on the anode side, the conductive pattern on the cathode side and the heat dissipation pattern are integrally formed.

[2-2. Effect etc]
In the present embodiment, as in the first embodiment, by configuring the conductive pattern 14 a to have a shape extending radially from the LED chip 12, the heat dissipation in the conductive pattern 14 a is improved.

  Furthermore, in the present embodiment, the composite pattern in which the conductive pattern 14b and the heat dissipation pattern 15 are integrally formed is also configured to radially extend from the LED chip 12, so the heat dissipation of the composite pattern is achieved. Has been improved. Further, when the conductive pattern 14 b and the heat dissipation pattern 15 are integrally formed, the formation of the conductive pattern 14 b is simplified. Specifically, when forming unnecessary patterns from copper foil formed on one surface of the substrate 11 to form each pattern, it is necessary to peel off the insulating region between the conductive pattern 14 b and the heat dissipation pattern 15. It disappears. Further, since the conductive pattern 14 b and the heat radiation pattern 15 are integrally formed, the conductive pattern 14 b and the heat radiation pattern 15 are always in a so-called thermally balanced state. Thereby, the heat dissipation of conductive pattern 14b and heat dissipation pattern 15 can be improved.

  In addition, the method similar to Embodiment 1 can be used for the setting method of an expansion angle.

(Other embodiments)
Although the case where the electronic component is the light emitting element (LED chip 12) has been described as an example in the first and second embodiments, it may be another electronic component (heat radiation source) that generates heat, such as a semiconductor element.

  Although the case where the conductive pattern 14a has the shape of an isosceles trapezoidal shape has been described in the first and second embodiments, the present invention is not limited to this. In FIG. 11, the angle between the axis X1 and one leg of the trapezoid and the angle between the axis X2 and the other leg of the trapezoid may be different.

  Although the case where the conductive patterns 14a and 14b and the heat radiation pattern 15 are copper foils has been described as an example in the first and second embodiments, other materials may be used. The heat dissipation pattern 15 and the conductive patterns 14a and 14b do not have to be made of the same material, and may be made of different materials.

  In the above-described first and second embodiments, although the case where the expansion angle is an angle between the axis X1 and the radially extending portion has been described as an example, the present invention is not limited to this. For example, it may be an angle between two radially extending lines. In this case, (a) in FIG. 11 has a spread angle of 60 degrees, (b) has a spread angle of 90 degrees, (c) has a spread angle of 120 degrees, and (d) has a spread angle of 180 degrees. Become.

  Although the case where the electronic device is a light projector has been described in the first and second embodiments, the above-described vehicle lamp or a lighting fixture such as a ceiling light, a tunnel light or a road light may be used.

  In addition, the present invention can be realized by arbitrarily combining components and functions in each embodiment without departing from the scope of the present invention or embodiments obtained by applying various modifications that those skilled in the art may think to each embodiment. The form is also included in the present invention.

1 substrate device 11 substrate 12, C1, C2 LED chip (electronic component)
13 Thermal Pads 14a, 14b Conductive Pattern 15 Thermal Pattern 16a, 16b Conducting Terminal 22 Thermal Fin

Claims (8)

A substrate device,
A substrate for mounting an electronic component on the surface, the substrate having on the surface a conductive pattern electrically connected to the electronic component and a heat dissipation pattern for releasing heat of the electronic component ;
And a long conductive terminal connected to the conductive pattern ;
The conductive pattern has a shape extending radially from the electronic component,
The heat dissipation pattern has a shape extending radially from the electronic component ,
Longitudinal length before Symbol conduction terminal, said case electronic components greater than the width in the direction intersecting the longitudinal direction of the thermal pad located on the back side, widening the angle of the conductive pattern 45 degrees When the length of the conductive terminal in the longitudinal direction is smaller than the width of the thermal pad, the expansion angle of the conductive pattern is greater than 0 degree and 45 degrees or less.
The heat dissipation pattern may be provided independently of the conductive pattern, and may be spaced apart from the conductive pattern.
Substrate device. The substrate has a plurality of the conductive patterns,
The substrate device according to claim 1. The substrate has two of the conductive patterns,
The heat dissipation pattern is electrically separated between the two conductive patterns.
The substrate device according to claim 1. The substrate further comprises the electronic component,
The substrate device according to any one of claims 1 to 3. The substrate device comprises two of the current-carrying terminals,
The substrate is further disposed between two of said conductive terminal comprises a thermal pad connected to the heat radiation pattern,
The substrate device according to claim 4. The electronic component is a semiconductor element,
The substrate device according to any one of claims 1 to 5. The electronic component is a light emitting element,
The substrate device according to any one of claims 1 to 6. The substrate device according to any one of claims 1 to 7,
Radiation fins disposed on the back side of the substrate,
Electronics.