JP2019087549A - LED package and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED package in which sufficient insulation resistance can be secured, durability can be enhanced and handling is easy by covering the outer peripheral surface of a base substrate exposed to the outside with an insulating film.
SOLUTION: A base substrate 12 made of a metal material and having a metal surface exposed on an upper surface 12a, a side surface 12b and a lower surface 12c, and a mount substrate disposed on the upper surface 12a of the base substrate 12 and having an opening 19 in the center. 14, a plurality of light emitting elements 15 disposed on the exposed upper surface 12 a of the base substrate 12, a reflection frame 17 provided on the mount substrate 14 along the outer periphery of the opening 19, and the reflection frame 17 And the internal electrode 22 and the external electrode 23 provided on the mount substrate 14 for supplying power to the plurality of light emitting elements 15 and the side surface 12 b of the base substrate 12. And an insulating film 24 covering the lower surface 12c.
[Selected figure] Figure 5

Description

  The present invention relates to a COB type LED package formed using a metal base substrate and a method of manufacturing the same.

  In recent years, a chip on board (COB) type LED package has been used in which a plurality of light emitting elements are arranged on a mounting base substrate in response to the miniaturization of the design of a lighting fixture etc. (Patent Document 1) ). In this COB type LED package, an anode (positive electrode) and a cathode (negative electrode) are formed on a base substrate formed of aluminum or the like having high thermal conductivity, and a plurality of light emitting elements are mounted in a region to be a light emitting portion. After that, the entire light emitting portion is sealed with a silicone resin containing a phosphor.

  Unlike the SMD type LED package, such a COB type LED package can be directly attached to a heat dissipation unit such as a device casing or a heat sink. For this reason, the mounting process and the printed circuit board become unnecessary, and by directly mounting the plurality of light emitting elements on the base substrate made of aluminum or the like, it has excellent characteristics in heat dissipation.

JP, 2011-009298, A

  In the above-mentioned conventional COB type LED package, it is common to use the metal base substrate with the side surface and the back surface exposed in order to enhance heat dissipation. However, since the side surface and the back surface have heat dissipation as well as conductivity, in the case of an overcurrent or a lightning surge, in some cases, electrostatic breakdown may occur. As described above, the conventional COB type LED package has problems in durability, easiness of handling, and the like as compared with the SMD type package because the insulation resistance is low.

  Therefore, it is an object of the present invention to cover an outer peripheral surface of a base substrate exposed to the outside with an insulating film so that sufficient insulation resistance can be secured, and the LED package and the durability thereof are enhanced and easy to handle. It is to provide a manufacturing method.

  In order to solve the above problems, the LED package of the present invention is formed of a metal material, and a base substrate having a metal surface exposed on the upper surface, side surface and lower surface, and disposed on the upper surface of the base substrate A plurality of light emitting elements disposed on the upper surface of the base substrate exposed by the opening, a reflective frame provided on the mount substrate along the outer periphery of the opening, and the reflective frame A resin body for sealing the plurality of light emitting elements, an internal electrode and an external electrode provided on the mount substrate for supplying power to the plurality of light emitting elements, and a side surface of the base substrate at least in the vicinity of the external electrode And an insulating film to be coated.

  In the method of manufacturing an LED package according to the present invention, a collective mount substrate made of an insulating material is bonded to the upper surface of a collective base substrate made of a metal material, and singulated by dicing the collective base substrate and the collective mount substrate. A method of manufacturing an LED package, comprising a plurality of LED packages comprising a base substrate and a mount substrate, wherein the predetermined width from the lower surface of the collective base substrate along the preset dicing dicing line to the collective mount substrate is reached. The groove portion is formed by half dicing, an insulating material is formed in the groove portion, and then the aggregate base substrate and the aggregate mount substrate are fully diced along the center line of the width of the groove portion to separate the pieces. The side surface of the base substrate is covered with an insulating film.

  According to the LED package of the present invention, at least the side surface of the base substrate from which the metal surface is exposed is covered with the insulating film, which causes an unexpected overcurrent from inside the device where the LED package is mounted or from outside such as lightning surge. Even in this case, dielectric breakdown of each light emitting element mounted in the light emitting unit can be effectively prevented. In addition, since the static electricity can be cut by the insulating film, durability can be improved and handling during storage and mounting can be facilitated.

  According to the method for manufacturing an LED package of the present invention, a collective base substrate having the collective mount substrate bonded to the upper surface is prepared, and a groove portion reaching the collective mount substrate from the lower surface side of the collective base substrate is formed by half dicing. By forming the insulating material in the groove and then fully dicing the groove along the center line, it becomes easy to use a COB type LED package with high insulation resistance, in which the insulating film is coated on the side of the individualized base substrate And it can be manufactured in large quantities.

It is a perspective view of the LED package of 1st Embodiment. It is a perspective view of the LED package of 2nd Embodiment. It is sectional drawing of the LED package of 2nd Embodiment. It is sectional drawing of the LED package of 3rd Embodiment. It is an action view of the LED package of 3rd Embodiment. It is explanatory drawing which shows the manufacturing process of the LED package of 2nd Embodiment. It is explanatory drawing which shows the manufacturing process of the LED package of 3rd Embodiment.

  FIG. 1 shows an LED package 11a according to a first embodiment of the present invention. The LED package 11 a has a rectangular base substrate 12, an opening 19 at the center, and a pair of external electrodes 23 outside the opening 19, and is mounted on the upper surface 12 a of the base substrate 12. 14 and a light emitting portion 13 formed in the opening 19.

  The base substrate 12 is formed of a metal material made of aluminum in a rectangular shape of a few dozen mm to several dozen mm square depending on the lighting application and the lighting scale, and the upper surface 12a on which the light emitting portion 13 and the mount substrate 14 are provided The side surface 12b and the lower surface 12c except for the metal surface are exposed. The side surface 12 b and the lower surface 12 c are used as a heat dissipating surface, and therefore, they are usually used in a state where the metal surface is exposed. However, in the present embodiment, a part of the side surface 12 b is covered with an insulating film 24. The insulating film 24 is formed so as to overlap the lower surface 12 c of the base substrate 12 from the lower surface of the mount substrate 14 on which the pair of external electrodes 23 are provided. Thus, the insulation resistance between the external electrode 23 and the lower surface 12c of the base substrate 12 can be enhanced by insulating the portion of the side surface 12b where the metal surface is exposed and close to the external electrode 23. Further, since the side surface 12 b and the lower surface 12 c of the base substrate 12 not covered with the insulating film 24 are exposed metal surfaces, sufficient heat dissipation can be secured in this portion. The insulating film 24 is a coating layer containing a ceramic insulating material, and can be formed by an electrodeposition method, a thermal spraying method, or the like.

  The mount substrate 14 is a plate member made of glass epoxy resin, and is formed in substantially the same size as the base substrate 12. At the center of the mount substrate 14, a circular opening 19 which is a formation region of the light emitting unit 13 is provided, and a part of the upper surface 12 a of the base substrate 12 is exposed through the opening 19. The pair of external electrodes 23 are external terminals, one of which is an anode terminal and the other of which is a cathode terminal, for supplying power from the outside to the plurality of light emitting elements 15 disposed in the light emitting portion 13. It is formed on the upper surface of the mount substrate 14.

  As shown in FIG. 5, the light emitting unit 13 includes a plurality of light emitting elements 15 disposed on the upper surface 12 a of the base substrate 12 exposed through the opening 19 of the mount substrate 14 and mounts along the outer periphery of the opening 19. A pair of internal electrodes 22 formed on the substrate 14, a ring-shaped reflection frame 17 formed on the mount substrate 14 along the outer periphery of the opening 19, and a plurality of light emitting elements surrounded by the reflection frame 17 And a resin body 18 for sealing 15. About several tens of the light emitting elements 15 are arranged at predetermined intervals in accordance with the light emission capacity, and are electrically connected to each other through the wire 16. Also. The pair of internal electrodes 22 is enclosed in a reflection frame 17 and electrically connected to the corresponding pair of external electrodes 23 by a wiring pattern (not shown) formed on the mount substrate 14.

  The resin body 18 is made of a silicone resin compatible with the light emission color of each light emitting element 15 and seals the mounting area of the light emitting element 15 surrounded by the reflection frame 17. The resin body 18 is formed by adding a predetermined amount of a fluorescent agent to a transparent resin base material and molding it. For example, yttrium aluminum garnet (a raw material of fluorescent particles) is used as an epoxy resin or silicone resin base material. It can be formed by mixing an appropriate amount of a fluorescent agent composed of YAG), a dye serving as a raw material of pigment particles, or the like.

  The plurality of light emitting elements 15 constituting the light emitting portion 13 use blue light emitting elements of the same kind and the same size made of a gallium nitride based compound semiconductor in order to emit a white light emitting color for general illumination. The blue light emitting element is composed of a substrate made of sapphire glass and a diffusion layer in which an n-type semiconductor and a p-type semiconductor are diffusion-grown on the substrate. The n-type semiconductor and the p-type semiconductor respectively have an n-type electrode and a p-type electrode on the top surface, and are electrically connected to each other through a wire 16.

  2 and 3 show the LED package 11b of the second embodiment. In the LED package 11 b, all four side surfaces 12 b were covered with the insulating film 24. The insulating film 24 is formed so as to overlap the lower surface 12 c of the base substrate 12 from the lower surface of the mount substrate 14 on which the pair of external electrodes 23 are provided. As described above, by insulating all the side surfaces 12b where the metal surface is exposed, it is possible to obtain higher insulation resistance than the LED package 11a according to the first embodiment. As a result, since the lower surface 12c of the base substrate 12 not covered with the insulating film 24 is an exposed metal surface, sufficient heat dissipation can be secured in this portion.

  FIG. 4 shows the LED package 11c of the third embodiment. In the LED package 11 c, the four side surfaces 12 b and the lower surface 12 c are all covered with the insulating film 24. The insulating film 24 is formed to completely cover from the lower surface of the mount substrate 14 on which the pair of external electrodes 23 are provided to the lower surface 12 c of the base substrate 12. As described above, by insulating all the side surface 12b and the lower surface 12c in which the metal surface is exposed, it is possible to obtain higher insulation resistance than the LED package 11b of the second embodiment.

  In the present embodiment, the base substrate 12 is formed of aluminum having a thickness of about 0.70 mm, and the mounting substrate 14 is formed of a glass epoxy resin having a thickness of about 0.1 mm, and the base substrate is formed via an adhesive sheet having a thickness of about 0.025 mm. It is joined to the upper surface of 12. The external electrode 23 formed on the mount substrate 14 is formed by gold plating on a resist having a thickness of about 0.015 mm.

  The insulation resistance of the LED package 11c is, as shown in FIG. 5, between the external electrode 23 and the side surface 12b of the base substrate 12 (A), between the internal electrode 22 and the upper surface 12a of the base substrate 12 (B) The distance between each light emitting element 15 and the upper surface 12 a of the base substrate 12 is measured at three points (C). The three levels of insulation resistance are (A) <(B) <(C). It is about 1.0 to 1.2 kV in (A), about 3.0 to 3.6 kV in (B), and about 4.5 kV in (C).

  In the present invention, the insulation resistance is enhanced by covering the exposed side surface 12 b and the lower surface 12 c of the base substrate 12 with the insulating film 24 made of a ceramic-based insulating material such as zirconia (ZrO 2) or aluminum nitride (AlN). Is configured. The insulating film 24 can be selected from two types: the case of only the side surface 12 b of the base substrate 12 and the both of the side surface 12 b and the lower surface 12 c. By covering the side surface 12 b of the base substrate 12 with the insulating film 24, the insulation resistance between (A) the external electrode 23 and the side surface 12 b of the base substrate 12 can be enhanced, and the insulating film is formed on the lower surface 12 c of the base substrate 12. By covering 24, it is possible to increase the insulation resistance between (B) the internal electrode 22 and the upper surface 12a of the base substrate 12, and (C) the light emitting element 15 and the upper surface 12a of the base substrate 12.

  Next, the result of having performed the withstand voltage test with respect to the LED package 11c of the said structure is shown. In this test, the pair of external electrodes 23 on the mount substrate 14 is short-circuited, and an alternating voltage is applied between the pair of external electrodes 23 and the lower surface 12 c of the base substrate 12. Then, the dielectric breakdown voltage was measured by changing the alternating voltage value at which dielectric breakdown occurs between the internal electrode 22 and the external electrode 23 and the base substrate 12. The material of the insulating film 24 used for this measurement was made of two types of zirconia (ZrO2) and aluminum nitride (AlN), and the exposed metal surface of the base substrate was coated by electrodeposition.

  In the case of the conventional COB type base substrate in which the metal exposed surface is not subjected to insulation processing, the dielectric breakdown voltage is about 1 kV. On the other hand, in the present invention, the dielectric breakdown voltage in the case where the side surface 12 b of the base substrate 12 is covered with the insulating film 24 is +0.7 kV or more, and both the side surface 12 b and the lower surface 12 c are covered with the insulating film 24 It was confirmed to be +2 kV or more. From this, by covering the insulating film 24 at least on the side surface 12 b of the base substrate 12, particularly in the vicinity of the pair of external electrodes 23, a higher degree of insulation resistance can be achieved with respect to the conventional general COB type LED package. You can get it. On the other hand, by forming the insulating film as a metal surface without forming the insulating film on the lower surface 12 c side of the base substrate 12, in this portion, it is possible to carry out a design giving priority to heat dissipation over insulation resistance.

  FIG. 6 shows a manufacturing process for collectively manufacturing a plurality of LED packages 11 b in which only the side surface 12 b of the base substrate 12 is covered with the insulating film 24. First, a collective substrate 31 is prepared in which a collective mount substrate 34 made of a resin material having the same planar size as the collective base substrate 32 is joined to the collective base substrate 32 made of a metallic material that can form a plurality of LED packages 11b (step a). A plurality of openings 19 are provided in advance in the collective mount substrate 34, and internal electrodes and external electrodes (not shown) are formed around the openings 19, respectively.

  With the lower surface 32c of the collective base substrate 32 up, dicing lines 35 for dividing into the individual LED packages 11b are set. Then, along the dicing lines 35, the collective base substrate 32 is half-diced until it reaches the collective mount substrate 34 (steps b and c).

  In the next step d, the insulating film 24 is formed only in the dicing groove 36, and the lower surface 32c of the collective base substrate 32 is left as it is in the metal surface. Then, the collective base substrate 32 and the collective mount substrate 34 are fully diced along the dicing line 35 which is the center line of the dicing groove 36 (step e). By this full dicing, only the side surfaces 12 b of the plurality of divided base substrates 12 are covered with the insulating film 24.

  Then, a plurality of light emitting elements 15 are placed in a reflection frame 17 provided along the opening 19 of the mount substrate 14 to form a light emitting portion 13 sealed by a resin body, whereby the individual LED packages 11 b Complete (step f).

  FIG. 7 shows a manufacturing process for collectively manufacturing a plurality of LED packages 11c in which the side surface 12b to the lower surface 12c of the base substrate 12 are covered with the insulating film 24. Steps a to c are the same as those in FIG. 6, but the insulating film 24 is covered with the inside of the dicing grooves 36 formed by half dicing in step c and the entire lower surface 32c of the collective base substrate 32. This coating is performed by electrodeposition or thermal spraying (step d). After the insulating film 24 is coated, the collective base substrate 32 and the collective mount substrate 34 are fully diced along the dicing lines 35. By this full dicing, the insulating film 24 is coated on the side surfaces 12 b and the lower surface 12 c of the plurality of divided base substrates 12 (step e).

  Then, as shown in FIG. 1 and FIG. 2, the light emitting portion 13 in which the plurality of light emitting elements 15 are mounted and sealed by the resin body is placed in the reflection frame 17 provided along the opening 19 of the mount substrate 14. By forming, each LED package 11c is completed (process f).

  As a manufacturing method other than that shown in FIG. 6 and FIG. 7, it is also possible to apply the steps shown below. First, an insulating sheet is attached to the lower surface 32c side of the collective base substrate 32, and then the entire insulating sheet is divided into pieces from the upper surface side of the collective mount substrate 34 bonded to the collective base substrate 32. Then, the insulating film 24 is coated on the side surface 12b of the base substrate 12 divided by this full dicing by an electrodeposition method or a thermal spraying method to form the side surface 12b of the base substrate 12 and the lower surface 12c to which the insulating sheet is attached. Can form the LED package 11 c covered with the insulating film 24. In addition, the LED package 11b in which the insulating film 24 is formed only on the side surface 12b of the base substrate 12 can be formed by peeling off the insulating sheet after the insulating process of the side surface 12b of the base substrate 12 is completed.

  As described above, in the LED package of the present invention, since the exposed metal surface of the base substrate is covered with the insulating film, the insulation resistance is enhanced, and an unexpected overcurrent such as a lightning surge occurs. Also, the dielectric breakdown can be effectively prevented. Further, by forming the insulating film only on the side surface of the base substrate and exposing the metal surface on the lower surface side to be the mounting surface, it is possible to have both heat dissipation and insulation resistance. Furthermore, since electrostatic resistance is also obtained, handling when the LED package is accommodated in or removed from the packaging tray is also facilitated.

  Further, in the method of manufacturing an LED package according to the present invention, the insulating film is formed by electrodeposition or thermal spraying in the dicing groove formed by half-dicating the aggregate substrate by the electrodeposition method or the thermal spraying method, and then the individual LEDs are full dicing. It can be divided into packages. This makes it possible to easily and mass-produce a COB type LED package with high insulation resistance.

11a, 11b, 11c LED package 12 base substrate 12a upper surface 12b side surface 12c lower surface 13 light emitting portion 14 mount substrate 15 light emitting element 16 wire 17 reflection frame 18 resin body 19 opening 22 internal electrode 23 outer electrode 24 insulating film 31 collective substrate 32 assembly Base substrate 34 Collective mounting substrate 35 Dicing line 36 Dicing groove

Claims (6)

A base substrate formed of a metal material and having a metal surface exposed on the upper surface, the side surface, and the lower surface;
A mounting substrate disposed on the upper surface of the base substrate and having an opening at a central portion thereof;
A plurality of light emitting elements disposed on the upper surface of the base substrate exposed by the opening;
A reflective frame provided on the mount substrate along the outer periphery of the opening;
A resin body for sealing a plurality of light emitting elements surrounded by the reflection frame;
Internal and external electrodes provided on the mount substrate and supplying power to the plurality of light emitting elements;
An insulating film which covers the side surface of the base substrate at least in the vicinity of the external electrode. In claim 1,
An LED package in which the base substrate has thermal conductivity. In claim 1,
The LED package in which the insulating film covers the entire side surface and the entire lower surface of the base substrate. In any one of claims 1 to 3,
The LED package whose said base substrate is aluminum. A collective mount substrate made of an insulating material is bonded to the upper surface of a collective base substrate made of a metal material, and the collective base substrate and the collective mount substrate are diced to obtain an LED package consisting of a singulated base substrate and a mount substrate. A method of manufacturing a plurality of LED packages, comprising:
A groove portion having a predetermined width that reaches the collective mounting substrate is formed by half dicing from a lower surface of the collective base substrate along a preset dicing dicing line.
After forming an insulating material in the groove, the aggregate base substrate and the aggregate mount substrate are fully diced along the center line of the width of the groove to cover the side surface of the singulated base substrate with the insulating film. LED package manufacturing method. In claim 5,
An insulating material is formed in the groove and an insulating film is coated on the lower surface of the aggregate base substrate, and the aggregate base substrate and the aggregate mount substrate are fully diced along the center line of the width of the groove, Method of manufacturing an LED package in which the side surface and the lower surface of the formed base substrate are covered with an insulating film.

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