JP3668438B2 - Chip light emitting diode - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a chip light emitting diode (LED) used mainly for key illumination of portable equipment, backlight of LCD (liquid crystal display) and the like.
[0002]
[Prior art]
  Conventionally, a chip LED is formed by mounting an LED chip on a substrate such as a glass epoxy substrate or MID (resin molding substrate) method, and packaging it by transfer molding or casting method using an epoxy resin. Is done. At that time, as a countermeasure against resin leakage at the time of molding, the top of the through-hole hole for conduction is covered with a copper foil, a resist, a sheet or the like.
[0003]
  When a plurality of LEDs are mounted in one package, generally, LED chips are arranged on the same layer of a substrate, and circuits are separated by patterning.
[0004]
[Problems to be solved by the invention]
  However, the conventional chip LED has the following problems. That is, when a plurality of LEDs are mounted in one package, the current that can flow through the LEDs cannot be increased due to the thermal resistance of the package. Therefore, when three color LED chips of R (red), G (green), and B (blue) are mounted in one package and mixed color light emission is performed, the rated current must be reduced and the luminous intensity is increased. It is not possible.
[0005]
  In that case, simply increasing the size of the package can lower the thermal resistance, but it is not possible to simply increase the size of the package due to the demand for miniaturization.
[0006]
  Therefore, in order to obtain the light intensity necessary to illuminate a certain light emitting area, it is necessary to use a plurality of LEDs per color, which causes an increase in price. Furthermore, by using a plurality of LED chips per color, it is necessary to suppress variations in luminous intensity and wavelength of individual LED chips corresponding to the same color, and the troublesome operation of adjusting the luminous intensity and wavelength is necessary. become.
[0007]
  For convenience of driving, an anode common is necessary when connecting a plurality of LEDs mounted in one package. However, in that case, it is necessary to separate the die areas of the individual LED chips, and there is a problem that the heat radiation land cannot be made common. Furthermore, since the total die area area is increased, there is a problem that the chip gap is wide, the display quality at the time of color mixture is lowered, and the package size is increased.
[0008]
  As described above, how to reduce the thermal resistance in a small one package incorporating a plurality of LEDs is a big issue.
[0009]
  Accordingly, an object of the present invention is to provide a small chip LED having a low thermal resistance on which a plurality of LED chips are mounted.
[0010]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention provides a chip LED in which an LED chip mounted on a substrate is sealed with a resin, and the substrate has a multilayer structure in which two layer substrates are laminated. The number of the LED chips is three or more, and at least one of the LED chips is mounted on a different layer substrate from the other LED chips, and each LED chip is mounted on the surface of each layer substrate. The electrode pattern to be connected is formed,The LED chip mounted on a different layer substrate from the other LED chips is an LED chip that generates a larger amount of heat than the other LED chips.the aboveLarge calorific valueIt is characterized in that at least one of the thickness and area of the electrode pattern of the layer substrate on which the LED chip is mounted is made larger than the electrode pattern of the other layer substrate to improve the heat radiation amount.
[0011]
  According to the said structure, a board | substrate is comprised in the laminated structure by two layer substrates,Larger heat generation than other LED chipsAt least one LED chip is mounted on a layer substrate different from the other, and at least one of the thickness and area of the electrode pattern of the layer substrate on which the at least one LED chip is mounted is greater than the electrode pattern of the other layer substrate. Increased heat dissipation to increase theMemorandumBy making the area and thickness of the electrode pattern of the layer substrate on which the LED chip with a large amount of heat is mounted larger than the electrode pattern of the other layer substrate, the heat dissipation of the LED chip with a large amount of heat generation is improved, and the thermal resistance Can be reduced.
[0012]
  In one embodiment, in the chip LED of the present invention, there is one LED chip mounted on a layer substrate different from the other LED chips, and this one LED chip is mounted at the center of the layer substrate. ing.
[0013]
  According to this embodiment, since one LED chip mounted on a layer substrate different from the above is mounted at the center of the layer substrate, for example, the other layer substrate stacked on this layer substrate. A groove, a notch or a hole for exposing the one LED chip is provided at the center of the LED, and other LED chips are arranged around the groove, the notch or the hole, so that a plurality of LED chip dies can be formed at the anode common. Even if the areas are separated, the die pitch of each LED chip is narrowed to improve the quality during mixed color light emission. Furthermore, the groove, notch or hole provided in the central portion of the other layer substrate forms a so-called cup structure, and the luminous efficiency of the one LED chip disposed therein can be improved.The
[0014]
  MaIn one embodiment, in the chip LED of the present invention, one of the two layer substrates has both arms and is substantially U-shaped.
[0015]
  According to this embodiment, one of the two layer substrates has a substantially U shape with both arms. Therefore, the area of the electrode pattern formed on the layer substrate that does not have the both arm portions of the two layer substrates can be widened to improve heat dissipation. That is, by laminating the layer substrate not having both arms and the layer substrate having both arms, the thermal resistance is reduced, the size is reduced, and the mounting pitch of each LED chip is reduced to display quality. It is possible to improve this.
[0016]
  In one embodiment, in the chip LED of the present invention, the LED chip mounted on a different layer substrate from the other LED chips is a G-color LED chip.
[0017]
  Since the forward voltage Vf is high and the luminous intensity ratio for white light emission is high, the amount of heat generated by the G color LED chip is the largest. According to this embodiment, the G-color LED chip having a large calorific value is mounted on a different layer substrate from the LED chips of other colors. Therefore, an increase in the area of the cathode pattern for the G-color LED chip that generates a large amount of heat is realized.
[0018]
  In one embodiment, in the chip LED of the present invention, the electrode pattern formed on each layer substrate is a cathode pattern, and a common anode pattern is provided on the light emitting surface of the light emitting side layer substrate, while the light emitting side is opposite to the light emitting side. A back surface pattern connected to the cathode pattern for each of the LED chips is provided on the anti-light emitting surface of the layer substrate, and the light emitting side layer substrate extends from the light emitting surface to the anti-light emitting surface at both corners. A notch is provided, and a metal foil electrically connected to the common anode pattern is formed on the inner wall of the notch, and the center of the one side surface of the layer substrate on the anti-light emitting side is repelled from the light emitting surface. A notch leading to the light surface is provided, and the cathode pattern for the LED chip mounted on a different layer substrate from the other light emitting diode chips on the inner wall of the notch The metal foil electrically connected is formed a back pattern for LED mounted on different layers substrate chips and the other light-emitting diode chips.
[0019]
  According to this embodiment, at the time of mounting, each one end of the back surface pattern for each LED chip provided on the anti-light emitting surface of the layer substrate on the anti-light emitting side constituting the substrate corresponds to the corresponding mounting on the mount surface. One end of a notched metal foil connected to the pattern and provided at both corners of the side surface of the layer substrate on the light emitting side and electrically connected to the common anode pattern is connected to the corresponding mounting pattern on the mount surface . Thus, the LED chip is mounted as a side light emitting type in which the light emitting direction of each LED chip is parallel to the mount surface. At that time, since there is a notch provided at one corner on one side of the layer substrate on the light emitting side and the center of the one side surface on the layer substrate on the anti-light emitting side at the connection position with the mounting pattern, The heat dissipation at the time is improved.
[0020]
  Further, at the time of formation, a through hole which is shared by two adjacent chip LEDs and becomes a notch at the center of the one side surface after the division is divided by the stacked light emitting side layer substrate. The resin is prevented from leaking to the non-light-emitting side through the through hole during resin sealing.
[0021]
  In one embodiment, in the chip LED of the present invention, the electrode pattern formed on each layer substrate is a cathode pattern, and a common anode pattern is provided on the light emitting surface of the light emitting side layer substrate, while the light emitting side is opposite to the light emitting side. The back surface pattern connected to the cathode pattern for each of the LED chips is provided on the anti-light emitting surface of the layer substrate, and the light emitting surface of the light emitting side layer substrate is provided at one corner of each of the two layer substrates. Is formed on the inner wall of the notch, and a metal foil electrically connected to the common anode pattern is formed on the inner wall of the notch. A notch from the light emitting surface to the anti-light emitting surface is provided at the center of the one side surface of the substrate, and an LE mounted on a layer substrate different from the other light emitting diode chips is provided on the inner wall of the notch. Metal foil for electrically connecting the back surface pattern for LED chips mounted on different layers the substrate is formed a cathode pattern and the other light emitting diode chip for the chip.
[0022]
  According to the above configuration, during mounting, each surface of the back surface pattern for each of the LED chips provided on the anti-light emitting surface of the layer substrate on the anti-light emitting side constituting the substrate corresponds to the mount surface. Connected to the mounting pattern. Further, one end of the light emitting side of the notched metal foil provided at one side corner of the two layer substrates and electrically connected to the common anode pattern is connected to the corresponding mounting pattern on the mount surface. Is done. Thus, the LED chip is mounted as a top light emitting type in which the light emitting direction of each LED chip is perpendicular to the mount surface.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 is a perspective view from the light emitting surface (front surface) side of the chip LED of the present embodiment. FIG. 2 is a perspective view from the side opposite to the light emitting surface (back surface) of the chip LED shown in FIG. FIG. 3 is a side view of the chip LED shown in FIG. 4 is a cross-sectional view taken along the line AA ′ in FIG. FIG. 5 is a view showing a state in which the mold resin 21 is removed from the state of FIG.
[0024]
  The chip LED in the present embodiment is a chip LED on which LED chips of three colors of R, G, and B are mounted. In general, a GaAlInP LED chip is used for R, and an InGaN LED chip is used for G and B. However, the InGaN LED chip has a high forward voltage Vf of about 3.5V. Further, when white light is emitted by mixing R, G, and B, a luminous intensity ratio of about R: G: B = 1: 7: 2 is required. As a result, the amount of heat generated by the G-color LED chip is the largest.
[0025]
  1 to 4, the first layer substrate 1 having the groove 2 and substantially U-shaped, and the second layer substrate 3 on which the first layer substrate 1 is laminated constitute a substrate. In the first layer substrate 1, R, B2 color LED chips 4, 5 are mounted on arms extending on both sides of the groove 2. On the other hand, the G-color LED chip 6 is mounted between the arms of the first layer substrate 1 in the second layer substrate 3.
[0026]
  Here, since the anode common is generally required for the convenience of the drive system, the LED lines 4, 6 and 5 of the R, G and B colors are common, and the cathode line is the LED chip 4, 6, and 5 respectively. It is necessary to make it independent every 5th. Therefore, the die area of the R and B color LED chips 4 and 5 is formed by processing the groove 2 in the first layer substrate 1 by NC (numerical control) method or the like. Further, as shown in FIG. 5, an anode pattern 10 made of a Cu foil common to all the LED chips 4, 5, 6 is formed on the base 22 on the side opposite to the groove 2 in the first layer substrate 1. The first layer substrate 1 is laminated and bonded to the second layer substrate 3.
[0027]
  In the laminated structure of the first layer substrate 1 and the second layer substrate 3, a G LED chip 6 having a large heat generation amount is mounted on the second layer substrate 3 in the groove 2 of the first layer substrate 1. . The cathode pattern (Cu foil 7) of the die bond portion is the same as the cathode pattern (Cu foils 8 and 9) of the die bond portion for the R and B color LED chips 4 and 5 on the first layer substrate 1 and the first layer substrate. Separated by 1. As a result, the Cu foil 7 for the G color LED chip 6 provided on the surface of the second layer substrate 3 is replaced with the Cu foil for the R, B color LED chips 4 and 5 provided on the surface of the first layer substrate 1. It is possible to form an area wider than the foils 8 and 9. In addition, the Cu foil 7 for the G color LED chip 6 can be formed thicker (35 μm to 70 μm) than the Cu foils 8 and 9 for the R and B color LED chips 4 and 5.
[0028]
  Therefore, the heat dissipation of the G color LED chip 6 with a large calorific value mounted on the second layer substrate 3 can be improved. At the same time, since the so-called cup structure is formed by the arm portion of the first layer substrate 1, the luminous efficiency of the G-color LED chip 6 can be improved.
[0029]
  Connection to the mounting terminal is performed by configuring the anode common line through the 1/4 through hole 11 of the first layer substrate 1. That is, the R-color LED chip 4 is mounted on the cathode pattern 8 provided on the arm portion of the first layer substrate 1, and the anode pattern 10 and the anode terminal are connected by the Au wire 12. Similarly, the B-color LED chip 5 is mounted on the cathode pattern 9, and the anode pattern 10 and the anode terminal are connected by the Au wire 13. On the other hand, the G LED chip 6 is mounted on the cathode pattern 7 provided on the second layer substrate 3, and the anode pattern 10 and the anode terminal are connected by the Au wire 14. Here, as shown in FIG. 5, both end portions of the anode pattern 10 are formed in the 1/4 through holes 11 and 11 as the notches provided at both side corners on the lower side of the first layer substrate 1 in the figure. It extends to the wall.
[0030]
  In this way, the anode common line passing through the anode terminal-Au wires 12, 13, 14-anode pattern 10-1 / 4 through hole 11 of each LED chip 4, 5, 6 is configured. In addition, the 1/4 through-hole 11 shares one circular cross-sectional through-hole formed in the substrate material of the first layer substrate 1 with the four chip LEDs adjacent to each other when the chip LED is formed. After the chip LED is completed, it is formed by dividing into individual chip LEDs by dicing.
[0031]
  On the other hand, the cathode terminal of the R color LED chip 4 mounted on the cathode pattern 8 of the first layer substrate 1 is connected to the cathode pattern 8. The upper corner portion of the cathode pattern 8 in the drawing extends to the inner wall surface of the 1/4 through hole 15 provided in common on the upper side corner of the first layer substrate 1 and the second layer substrate 3 in the drawing. doing. Further, on the inner wall surface of the 1/4 through hole 15, a first back surface pattern 16 made of Cu foil provided on the R color LED chip 4 mounting side on the back surface (the LED chip non-mounting surface) of the second layer substrate 3 is provided. It is connected. Thus, the first cathode line is formed via the cathode terminal-cathode pattern 8-1 / 4 through hole 15 -first back surface pattern 16 of the R-color LED chip 4. In addition, the 1/4 through-hole 15 includes four circular through-holes adjacent to each other that are formed in the substrate material of each of the first layer substrate 1 and the second layer substrate 3 when the chip LED is formed. The chip LED is shared, and after the chip LED is completed, it is formed by dicing into individual chip LEDs.
[0032]
  The cathode terminal of the B color LED chip 5 mounted on the cathode pattern 9 of the first layer substrate 1 is connected to the cathode pattern 9. The upper corner portion of the cathode pattern 9 in the drawing extends to the inner wall surface of the 1/4 through hole 17 provided in common on the upper side surface corner of the first layer substrate 1 and the second layer substrate 3 in the drawing. doing. Further, a second back surface pattern 18 made of a Cu foil provided on the B color LED chip 5 mounting side on the back surface of the second layer substrate 3 is connected to the inner wall surface of the 1/4 through hole 17. Thus, the second cathode line is formed via the cathode terminal of the B color LED chip 5 -the cathode pattern 9-1 / 4 through hole 17 -the second back surface pattern 18.
[0033]
  The cathode terminal of the G color LED chip 6 mounted on the cathode pattern 7 of the second layer substrate 3 is connected to the cathode pattern 7. The central portion of the lower end of the cathode pattern 7 in the drawing extends to the inner wall surface of the ½ through hole 19 as the notch provided in the center of the lower side surface of the second layer substrate 3 in the drawing. Yes. Further, a third back surface pattern 20 made of a Cu foil provided at an intermediate portion of the back surface of the second layer substrate 3 is connected to the inner wall surface of the 1/2 through hole 19. Thus, a third cathode line is formed via the cathode terminal-cathode pattern 7-1 / 2 through hole 19-third back surface pattern 20 of the G-color LED chip 6. The 1/2 through-hole 19 is shared by two chip LEDs adjacent to each other through one circular cross-section through hole formed in the substrate material of the second layer substrate 3 when forming the chip LED. After the chip LED is completed, it is formed by dividing into individual chip LEDs by dicing.
[0034]
  As described above, the 1/4 through-holes 11, 15, and 17 are configured with 1 / 4-divided holes, while the 1/2 through-hole 19 is configured with 1 / 2-divided holes, so that The number of through holes to be formed can be reduced as compared with the case of forming with one hole, and the cost can be reduced.
[0035]
  As described above, the surfaces (LED chip mounting surfaces) of the first layer substrate 1 and the second layer substrate 3 on which the LED chips 4, 6, 5 of R, G, B colors are mounted are sealed with the mold resin 21. Has been.
[0036]
  Here, as shown in FIG. 4, at the position of the ½ through hole 19 provided in the lower center portion of the second layer substrate 3, the base portion 22 provided with the anode pattern 10 in the first layer substrate 1. Is located. That is, at the time of forming the chip LED, one through hole shared by the two adjacent chip LEDs is blocked by the substrate material of the first layer substrate 1 in the two adjacent chip LEDs. Therefore, when the surface of the laminate of the first layer substrate 1 and the second layer substrate 3 is filled with the mold resin 21, the resin passes through the through hole that becomes the ½ through hole 19 and the resin passes through the second layer substrate 3. There is no leakage to the back side. Therefore, a process or material for closing the through hole with a Cu foil, a resist, or a sheet is not necessary, and the process can be shortened and the cost can be reduced.
[0037]
  FIG. 6 is an explanatory diagram of a lamination process of the first layer substrate 1 and the second layer substrate 3. FIG. 6A shows the substrate material 1 ′ of the first layer substrate 1, and a portion corresponding to one chip LED is shown by a solid line. Similarly, FIG. 6B shows a substrate material 3 ′ of the second layer substrate 3, and a portion corresponding to one chip LED is indicated by a solid line.
[0038]
  In FIG. 6 (a), through-holes 11 'having a circular cross section centering on the intersection are formed every other row at the intersection of the dividing line to each chip LED. Further, on the dividing line 26 in one direction where the through-hole 11 ′ is not drilled, the dividing line 26 is sandwiched in the middle of the intersection with the dividing line 27 in the other direction orthogonal to the one direction. A rectangular hole 2 ′ constituting the groove 2 of the two chip LEDs adjacent to each other is formed. And Cu foil 8 ', 9' used as cathode pattern 8,9 after division | segmentation is formed in the both sides to the said one direction of rectangular hole 2 '. In addition, a Cu foil 10 ′ is formed on the dividing line 25 in which the through hole 11 ′ is formed, and becomes the anode pattern 10 of two chip LEDs adjacent to each other with the dividing line 25 interposed therebetween. Further, a Cu foil is also formed on the inner wall of the through hole 11 ′ and is connected to the Cu foil 10 ′.
[0039]
  Further, in FIG. 6 (b), a through-hole having a circular cross section having a center at the dividing line 28 is provided at every other line of the dividing line in the one direction at the middle of the intersection with the dividing line 30 in the other direction. Hole 19 'is drilled. A Cu foil 7 ′ that becomes the cathode pattern 7 after the division is formed except for a region having a predetermined width centered on the dividing line 30. Further, a Cu foil is also formed on the inner wall of the through hole 19 ′ and is connected to the Cu foil 7 ′. Further, a Cu foil (not shown) is formed on the back surface, which becomes the first, second, and third back surface patterns 16, 18, and 20 after the division.
[0040]
  Thus, the Cu foils 8 ′ and 9 ′ to be the cathode patterns 8 and 9 and the Cu foil 7 ′ to be the cathode pattern 7 are formed in different layers of the first layer substrate 1 and the second layer substrate 3. As a result, the cathode pattern 7 can be formed larger in area and thicker than the cathode patterns 8 and 9 to improve heat dissipation.
[0041]
  A substrate material 1 ′ of the first layer substrate 1 shown in FIG. 6A and a substrate material 3 ′ of the second layer substrate 3 shown in FIG. 6B are divided into a dividing line 25, a dividing line 28, and a dividing line. 27 and the dividing line 30 are laminated and bonded together. After that, the substrate material 1 ′ and the substrate material 3 ′ are penetrated at the intersecting positions of the dividing lines 26 (29) and the dividing lines 27 (30) every other row, and then become 1/4 through holes 15 and 17. A through hole (not shown) is drilled, and Cu foil is applied to the inner wall of the through hole to electrically connect the Cu foils 8 'and 9' to the first and second back surface patterns 16 and 18. Then, as described above, the R and B color LED chips 4 and 5 and the G color LED chip 6 are mounted, connected by the Au wires 12, 13 and 14, and sealed by the mold resin 21.
[0042]
  In that case, the through hole 19 ′ is blocked by the first layer substrate 1. Therefore, as described above, the resin is prevented from leaking to the back surface side of the second layer substrate 3 through the through hole 19 ′. Therefore, it is not necessary to close the through hole 19 ′ with a Cu foil, resist or sheet.
[0043]
  After that, the laminated structure of the first layer substrate 1 and the second layer substrate 3 as shown in FIG. 6 (c) is obtained by dividing by the dividing lines 25, 26, 27, 28, 29, 30. can get. However, in FIG. 6C, the R, BLED chips 4, 5, 6, Au wires 12, 13, 14, and mold resin 21 are omitted.
[0044]
  When the chip LED configured as described above is mounted on the mount surface, as shown in FIG. 7, the mounting patterns 31, 31 abut the lower ends of the 1/4 through holes 11, 11 in the figure. The lower end in the drawing of the first back surface pattern 16 is brought into contact with the mounting pattern 32, the lower end in the drawing of the second back surface pattern 18 is brought into contact with the mounting pattern 33, and the 1/2 through hole is formed in the mounting pattern 34. 19 and the third back surface pattern 20 are brought into contact with the lower end in the figure and connected by soldering or the like.
[0045]
  In that case, the 1/4 through-holes 11 and 11 are located in the mounting patterns 31 and 31 and the 1/2 through-hole 19 is located in the mounting pattern 34, thereby improving the heat dissipation characteristics during soldering. it can. Further, by fixing the first layer substrate 1 constituting the substrate to the mounting pattern 31 and fixing the second layer substrate 3 to the mounting patterns 32 to 34, the front surface side and the back surface side of the substrate can be fixed. It is possible to prevent the other side from floating from the mounting surface as in the conventional case where only one side of the substrate is fixed. Therefore, an effect can be exerted in positioning of the chip LED.
[0046]
  As described above, in the present embodiment, the substrate on which the LED chips 4, 6 and 5 of the R, G and B colors are mounted is a first layer substrate having both arms and having a substantially U shape. 1 and the second layer substrate 3 are formed in a two-layer structure. Then, the cathode patterns 8 and 9 for the R and B color LED chips 4 and 5 with a small amount of heat generation are provided on the arm portion of the first layer substrate 1, and the cathode pattern 7 for the G color LED chip 6 with a large amount of heat generation is provided on the first side. It is provided over substantially the entire surface of the two-layer substrate 3. In this way, by providing the cathode pattern for the LED chip with a small amount of heat generation and the cathode pattern for the LED chip with a large amount of heat generation on different substrates, the area of the cathode pattern for the LED chip with a large amount of heat generation can be increased. In addition, the heat dissipation can be improved by increasing the thickness. At that time, a cathode pattern with a small area for an LED chip with a small amount of heat generation is arranged on top of a cathode pattern for a LED chip with a large area and a large amount of heat generation. Therefore, even when the area of the cathode pattern for the LED chip that generates a large amount of heat is increased to improve heat dissipation and the anode common wiring is performed, the mounting pitch of the LED chips 4, 6, and 5 for each of the R, G, and B colors can be increased. It can be made small so that the display quality does not deteriorate.
[0047]
  Further, the G-color LED chip 6 mounted on the second layer substrate 3 is arranged inside both arms of the first layer substrate 1 stacked on the second layer substrate 3. Therefore, because of the so-called cup structure formed by the arms of the first layer substrate 1, the light emission efficiency of the G-color LED chip 6 can be improved.
[0048]
  Further, the cathode terminal of the G color LED chip 6 is connected to the cathode pattern 7 provided on the light emitting surface side of the second layer substrate 3, and the lower end portion of the cathode pattern 7 is provided at the lower end center portion of the second layer substrate 3. The third through-hole 19 is connected to the third back surface pattern 20 provided on the back surface of the second layer substrate 3. When the chip LED is formed, the through-hole 19 ′ that will later become the 1/2 through-hole 19 is blocked by the substrate material 1 ′ of the first layer substrate 1 to be laminated. Therefore, when sealing with the mold resin 21, it is possible to prevent the resin from leaking to the back surface side of the second layer substrate 3 through the through hole 19 ′. That is, unlike the prior art, it is not necessary to close the through hole 19 'with a copper foil, resist, or sheet, and the process can be shortened and the cost can be reduced.
[0049]
  Further, when the chip LED is mounted on the mount surface, the first layer substrate 1 is connected to the mounting pattern 31, and the second layer substrate 3 is connected to the mounting patterns 32-33. Therefore, it is possible to prevent positional deviation during soldering as compared with the case where only one side of the substrate is mounted on the mount surface. In addition, since the 1/2 through hole 19 exists at the position of the mounting pattern 34 and the 1/4 through hole 11 exists at the position of the mounting pattern 31, 1 / 4,1 corresponding to each mounting pattern 31, 34. / 2 The heat dissipation characteristics when soldering the Cu foils of the through holes 11 and 19 can be improved.
[0050]
  In the above embodiment, the mounting position of the R and B color LED chips 4 and 5 on the first layer substrate 1 and the mounting position of the G color LED chip 6 on the second layer substrate 3 are the positions shown in FIG. It is not limited to. Further, the shapes of the cathode patterns 7 to 9 and the anode pattern 10 are not limited to the above embodiments. Of course, the same effect can be obtained even if the stacking order of the first layer substrate 1 and the second layer substrate 3 is reversed, and the substrate layer can be divided for each LED chip 4, 5, 6. Is possible.
[0051]
  Further, the color of the mounted LED chip is not limited to R, G, B, and the number thereof is not limited to three. Further, the number of layer substrates to be stacked is not limited to two or three.
[0052]
  By the way, in the present embodiment, the following modifications are possible. That is, as shown in FIG. 8, the 1/4 through hole 43 for connecting the anode pattern (not shown: see FIG. 5) in the first layer substrate 41 to the mounting pattern is formed in the first layer substrate 41 and the second layer substrate 41. You may provide in common with both side corners of the lower side in the figure with the layer substrate 42. In that case, as shown in FIG. 9, it can be used as a top-emitting (top-emitting) chip LED. In FIG. 9, the Cu foils of the ¼ through holes 43 and 43 connected to the anode pattern are connected to the mounting patterns 44 and 44 at the end on the back surface side of the second layer substrate 3. Incidentally, 45 is a mounting pattern for the R color LED chip 48, 46 is a mounting pattern for the B color LED chip 49, and 47 is a mounting pattern for the G color LED chip 50.
[0053]
  In addition, in the first layer substrate 1 shown in FIGS. 1 to 5, by providing the groove 2 at the center of the upper end in the figure, it is possible to secure a mounting area for the R, B color LED chips 4 and 5 that generate a small amount of heat, A cup structure for improving the light emission efficiency of the G-color LED chip 6 is formed. The above-described function can also be achieved by providing a hole 52 at a substantially central portion of the first layer substrate 51 as shown in FIG. In other words, cathode patterns 53 and 54 for R and B color LED chips with a small amount of heat generation are provided on both sides of the hole 52, and the G color LED chip mounted on the second layer substrate is placed in the hole 52 of the first layer substrate 51. It is arranged. Reference numeral 55 denotes an anode pattern.
[0054]
  In the said embodiment, although Cu foil is used as said metal foil and various electrode patterns, this invention is not limited to Cu.
[0055]
【The invention's effect】
  As is clear from the above, the chip LED of the present invention has a multilayer structure in which two layer substrates are stacked, and among the three or more mounted LED chips.High heat generation compared to other LED chipsAt least one is mounted on a layer substrate different from the others, and at least one of the thickness and area of the electrode pattern of the layer substrate on which the at least one LED chip is mounted is made larger than the electrode pattern of the other layer substrate. As a result, the heat dissipation amount has been improved.OfThe heat dissipation can be improved and the thermal resistance can be reduced.
[0056]
  In addition, the chip LED of one embodiment has one LED chip mounted on a layer substrate different from the above, and this one LED chip is mounted in the center of the layer substrate. A groove, a notch or a hole for exposing the one LED chip is provided in the central portion of the other layer substrate to be laminated, and another LED chip is disposed around the groove, the notch or the hole, thereby forming an anode. Even when the die areas of a plurality of LED chips are separated at the time of common, the die pitch of each LED chip can be reduced. Therefore, the quality at the time of mixed color light emission can be improved and the size of the package can be reduced. That is, it is possible to provide a small chip LED having a low thermal resistance on which a plurality of LED chips are mounted. Further, a groove, a notch or a hole provided in the central portion of the other layer substrate forms a so-called cup structure, and the light emission efficiency of the one LED chip disposed therein is improved.The
[0057]
  MaIn addition, in the chip LED of one embodiment, one of the two layer substrates is formed to have a substantially U shape with both arms. Therefore, the area of the electrode pattern formed on the layer substrate that does not have the both arm portions of the two layer substrates can be widened to improve heat dissipation. That is, the layer substrate not having both arms and the layer substrate having both arms are stacked, for example, an LED chip having a small heat generation amount is mounted on the both arm portions, while an LED chip having a large heat generation amount is mounted on the both arms. By mounting between both arms, the thermal resistance can be reduced, the size can be reduced, and the mounting pitch of each LED chip can be reduced to improve the display quality.
[0058]
  Further, in the chip LED of one embodiment, since the LED chip mounted on the layer substrate different from the above is the G color LED chip, the G color LED chip having a large calorific value is different from the LED chips of other colors. It can be mounted on a layer substrate. Therefore, it is possible to realize an increase in the area of the cathode pattern for the G color LED chip that generates a large amount of heat.
[0059]
  Furthermore, when each LED chip is wired to the anode common, the interval between the LED chips of each color can be narrowed compared to the case where the LED chip is realized with a single layer substrate as in the conventional case, so that the color mixing at the time of mixed color light emission is improved. Display quality can be improved.
[0060]
  Further, in the chip LED of one embodiment, the electrode pattern formed on each of the layer substrates is a cathode pattern, a common anode pattern is provided on the light emitting surface of the layer substrate on the light emitting side, and the anti-light emitting surface on the layer substrate on the counter light emitting side. Is provided with a back surface pattern connected to the cathode pattern for each of the LED chips, and a notch extending from the light emitting surface to the anti-light emitting surface is provided at one corner of the light emitting side layer substrate, and the inner wall of the notch is provided. Forming a metal foil electrically connected to the common anode pattern, and providing a notch from the light emitting surface to the anti-light emitting surface at the center of the one side surface of the layer substrate on the anti-light emitting side. On the inner wall, a cathode pattern for an LED chip mounted on a layer substrate different from the other light emitting diode chips and a layer substrate different from the other light emitting diode chips are mounted. Since the metal foil for electrically connecting the back surface pattern for the LED chip is formed, one end of each back surface pattern provided on the anti-light emitting surface of the layer substrate on the anti-light emitting side is mounted on the mounting surface at the time of mounting. One end of a notched metal foil provided on the light emitting layer substrate and electrically connected to the common anode pattern can be connected to the corresponding mounting pattern on the mount surface. . Therefore, it can be mounted as a side light emitting type in which the light emitting direction of each LED chip is parallel to the mount surface. At that time, since there is a notch provided in the light emitting side layer substrate and the counter light emitting side layer substrate at the connection position of the mounting pattern, heat dissipation during soldering can be improved. Further, since the light emitting side layer substrate and the counter light emitting side layer substrate are connected to the mounting pattern, the one surface side of the substrate does not float and positioning can be performed reliably.
[0061]
  Further, at the time of formation, a through hole that is shared by two adjacent chip LEDs and becomes a notch at the center of one side surface of the layer substrate on the side opposite to the light emitting side after being divided is closed by the layered layer substrate on the light emitting side. It is possible to prevent the resin from leaking through the through hole to the non-light emitting side during resin sealing. Therefore, unlike the prior art, it is not necessary to close the through hole with a copper foil or a resist, and the process can be shortened and the cost can be reduced.
[0062]
  Further, in the chip LED of one embodiment, the electrode pattern formed on each of the layer substrates is a cathode pattern, a common anode pattern is provided on the light emitting surface of the light emitting side layer substrate, and the anti light emitting surface of the anti light emitting side layer substrate is provided. Is provided with a back surface pattern connected to the cathode pattern for each of the LED chips, and a repulsion of the light emitting surface of the layer substrate on the light emitting side from the light emitting surface of the layer substrate on the light emitting side is repelled at one corner of the two layer substrates. A notch extending to the light surface is provided, a metal foil electrically connected to the common anode pattern is formed on the inner wall of the notch, and the center of the one side surface of the layer substrate on the anti-light emitting side is formed from the light emitting surface. A notch leading to the non-light emitting surface is provided, and the cathode pattern for the LED chip mounted on the layer substrate different from the other light emitting diode chip and the other light emitting are provided on the inner wall of the notch Since the metal foil electrically connected to the back surface pattern for the LED chip mounted on the layer substrate different from the ion chip is formed, each back surface pattern provided on the layer substrate on the anti-light-emitting side at the time of mounting Can be connected to the corresponding mounting pattern on the mounting surface. Further, one end of the light emitting side of the notched metal foil provided in common on the two layer substrates and electrically connected to the common anode pattern can be connected to the corresponding mounting pattern on the mount surface. Therefore, it can be mounted as a top light emitting type in which the light emitting direction of each LED chip is perpendicular to the mount surface.
[Brief description of the drawings]
FIG. 1 is a perspective view from the surface side of a chip LED of the present invention.
2 is a perspective view from the back side of the chip LED shown in FIG. 1. FIG.
FIG. 3 is a side view of the chip LED shown in FIG. 1;
4 is a cross-sectional view taken along the line AA ′ in FIG. 2;
FIG. 5 is a view showing a state where a mold resin is removed from the chip LED shown in FIG. 1;
6 is an explanatory diagram of a stacking process of a first layer substrate and a second layer substrate in FIG. 1. FIG.
7 is an explanatory diagram of mounting the chip LED shown in FIG. 1 on a mounting surface. FIG.
FIG. 8 is a perspective view of a chip LED different from FIG.
FIG. 9 is an explanatory diagram when the chip LED shown in FIG. 8 is used as a top emission type;
FIG. 10 is a perspective view of a first layer substrate different from those shown in FIGS.
[Explanation of symbols]
  1, 41, 51 ... first layer substrate,
  2 ... Groove,
  3, 42 ... second layer substrate,
  4,48 ... R color LED chip,
  5, 49 ... B color LED chip,
  6,50 ... G color LED chip,
  7, 8, 9, 53, 54 ... Cathode pattern,
10, 55 ... anode pattern,
11, 15, 17, 43 ... 1/4 through hole,
12, 13, 14 ... Au wire,
16 ... 1st back surface pattern,
18 ... second back pattern,
19 ... 1/2 through hole,
20 ... Third back surface pattern,
21 ... Mold resin,
25, 26, 27, 28, 29, 30 ... dividing line,
31, 32, 33, 34, 44, 45, 46, 47 ... mounting pattern,
52 ... hole.

Claims (6)

In a chip light emitting diode formed by sealing a light emitting diode chip mounted on a substrate with a resin,
The substrate has a multilayer structure in which two layer substrates are laminated,
The number of the light emitting diode chips is three or more, and at least one of the light emitting diode chips is mounted on a different layer substrate from the other light emitting diode chips,
On the surface of each layer substrate, an electrode pattern on which each light emitting diode chip is mounted and connected is formed,
The light emitting diode chip mounted on a different layer substrate from the other light emitting diode chips is a light emitting diode chip that generates a larger amount of heat than the other light emitting diode chips.
The heat radiation amount is improved by making at least one of the thickness and area of the electrode pattern of the layer substrate on which the light emitting diode chip having the large heat generation amount is mounted larger than the electrode pattern of the other layer substrate. Chip light emitting diode. The chip light emitting diode according to claim 1,
A chip light emitting diode, wherein one light emitting diode chip is mounted on a layer substrate different from the other light emitting diode chips, and the one light emitting diode chip is mounted at the center of the layer substrate. The chip light emitting diode according to claim 1,
One of the two layer substrates is a chip light emitting diode having both arms and having a substantially U shape. The chip light emitting diode according to claim 1,
A light emitting diode chip mounted on a different layer substrate from the other light emitting diode chips is a green light emitting diode chip. The chip light emitting diode according to claim 1,
The electrode pattern formed on each layer substrate is a cathode pattern,
A common anode pattern is provided on the light emitting surface of the layer substrate on the light emitting side, while a back surface pattern connected to the cathode pattern for each light emitting diode chip is provided on the anti-light emitting surface of the layer substrate on the anti-light emitting side. And
Notches extending from the light emitting surface to the anti-light emitting surface are provided at both corners of the light emitting side layer substrate, and a metal foil electrically connected to the common anode pattern is formed on the inner wall of the notch. And
A notch extending from the light emitting surface to the anti-light emitting surface is provided at the center of the one side surface of the layer substrate on the anti-light emitting side, and the inner wall of the notch is mounted on a layer substrate different from the other light emitting diode chips. A chip in which a metal foil for electrically connecting a cathode pattern for a light emitting diode chip and a back surface pattern for a light emitting diode chip mounted on a different layer substrate from the other light emitting diode chips is formed. Light emitting diode. The chip light emitting diode according to claim 1,
The electrode pattern formed on each layer substrate is a cathode pattern,
A common anode pattern is provided on the light emitting surface of the layer substrate on the light emitting side, while a back surface pattern connected to the cathode pattern for each light emitting diode chip is provided on the anti-light emitting surface of the layer substrate on the anti-light emitting side. And
A cutout from the light emitting surface of the light emitting side layer substrate to the antilight emitting surface of the anti-light emitting side layer substrate is provided at one corner of one side surface of the two layer substrates, and the common anode pattern is formed on the inner wall of the notch. A metal foil electrically connected to the
A notch extending from the light emitting surface to the anti-light emitting surface is provided at the center of the one side surface of the layer substrate on the anti-light emitting side, and the inner wall of the notch is mounted on a layer substrate different from the other light emitting diode chips. A chip in which a metal foil for electrically connecting a cathode pattern for a light emitting diode chip and a back surface pattern for a light emitting diode chip mounted on a different layer substrate from the other light emitting diode chips is formed. Light emitting diode.

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