JP2010272744A - Led module device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve totally inexpensive and high-efficiency heat exhaustion by separating an electric connection substrate and a heat exhaust (heat dissipation) substrate, and optimizing cost performances thereof. <P>SOLUTION: A post electrode component is constituted by supporting a plurality of post electrodes together on a support plate. An LED package is constituted by mounting an LED chip on an LED package substrate and connecting it to a wiring layer thereof, mounting the post electrode component on the wiring layer thereof and connecting the wiring layer and one end of the post electrode to each other, and peeling the support plate after resin sealing. A lens is fitted at a boring position of a bored secondary mounting substrate, and the LED package is mounted on the secondary mounting substrate so that a light emission surface of the LED chip faces the lens. The LED package is mounted on the secondary mounting substrate by connecting the other end of the post electrode to wiring on the secondary mounting substrate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an LED module device in which an LED package having an LED chip mounted on an LED package substrate as a primary mounting substrate is mounted on a secondary mounting substrate.

  An LED (Light Emitting Diode) is widely used as an element that has both low power consumption, reduced carbon dioxide, high durability, and energy saving. Such an LED is mounted on a mounting substrate to form an LED package, and is used for backlighting of electronic devices such as mobile phones, digital video cameras, and PDAs, large displays, road displays, and the like. . Since the LED itself is a light emitting element and emits heat, the LED package basically includes a heat dissipation device for cooling.

  In the current LED module, a ceramic substrate or a metal core (copper, aluminum) substrate is used as the primary mounting substrate, and this primary mounting substrate is mounted on the secondary mounting substrate with the light emitting surface facing upward, and heat is applied to the secondary mounting substrate. Is conducted to dissipate heat. FIG. 19 is a diagram showing an LED module provided with a heat dissipation device according to the prior art (see Non-Patent Document 1). The illustrated LED module has an LED package that is mounted on a dedicated unit substrate, which includes a copper plate and a printed wiring board. In an LED package, an LED chip, an optical component, and a phosphor sheet are mounted on a ceramic substrate. The LED chip is flip-chip bonded directly to the ceramic substrate with gold bumps, and the optical component and the phosphor sheet are fixed with silicon resin.

  In the conventional method using a ceramic substrate, the heat conduction of the ceramic substrate is worse than that of metals such as copper, so that heat cannot be radiated well, it is expensive, and the CTE (thermal expansion coefficient) with the secondary mounting substrate (printed wiring board) Due to the large difference, there are problems such as poor bonding and difficulty in processing. In addition, although the metal core substrate has better heat dissipation than the ceramic substrate, the secondary mounting substrate made of glass epoxy or the like has a poor thermal conductivity, so a multilayer substrate is used to increase the thermal conductivity. However, the current situation is that the output is reduced to be insufficient.

  Patent Document 1 discloses a configuration in which a hole is formed in a secondary mounting substrate and an LED package is attached thereto. However, this Patent Document 1 uses a metal lead extending from the side surface of the LED package body to attach the LED package. It is necessary to integrally mold the ceramic and the metal lead, and the configuration is complicated.

  Patent Document 2 discloses a post electrode component described later that can be used by the present invention.

Masaru Sugimoto et al. “High Power White LED Light Source for Lighting”, Matsushita Electric Works, Vol.53, No.1, http://panasonic-denko.co.jp/corp/tech/report/531j/pdfs/531_01.pdf

US 6,428,189 B1 International Publication WO2008 / 065896 A1

  In the current LED module, the side opposite to the light emitting surface of the LED chip is mounted on the module substrate, and heat is radiated through the module substrate. However, because the thermal resistance of the module substrate and the secondary mounting substrate is large, the heat of the chip is increased. Difficult to communicate.

  The present invention solves such problems, separates the electrical connection board (secondary mounting board) and the exhaust heat (heat dissipation) board (LED package board), optimizes each cost performance, and integrates them. The purpose is to realize low-cost and high-efficiency exhaust heat.

  In the LED module device and the manufacturing method thereof according to the present invention, an LED package having an LED chip mounted on an LED package substrate as a primary mounting substrate is mounted on the secondary mounting substrate. The post electrode component is configured by collectively supporting a plurality of post electrodes on a support plate. In an LED package, an LED chip is mounted on an LED package substrate and connected to the wiring layer, and a post electrode component is mounted on the wiring layer on the LED package substrate, and one end of the wiring layer and the post electrode. Are connected, and the support plate is peeled off after resin sealing. The secondary mounting board is perforated, and the LED package is mounted on the secondary mounting board so that the light emitting surface of the LED chip faces the perforation position. The LED package is mounted on the secondary mounting board by connecting the other end of the post electrode to the wiring on the secondary mounting board. A lens is attached to the drilling position of the drilled secondary mounting substrate.

  As the LED package substrate, a metal plate having good thermal conductivity is used for thermal diffusion or heat dissipation, and a wiring layer is formed on the upper surface of the LED package substrate via an insulating layer. As the secondary mounting substrate, a printed wiring board having a single-sided single-layer wiring in which a lens mounting portion is perforated is used. On the secondary mounting substrate, circuit elements including a control IC and passive components are mounted and connected. A heat sink is attached to the LED package substrate on the side surface opposite to the LED chip mounting surface. In addition, the lens mounting portion can be inclined and perforated on the secondary mounting substrate, and a reflective surface can be formed on the surface opposite to the perforated portion and the LED package mounting surface.

  According to the present invention, the electrical connection substrate (secondary mounting substrate) and the exhaust heat (heat dissipation) substrate (LED package substrate) are separated, and the cost performance can be optimized, and the total, inexpensive and highly efficient exhaust heat can be achieved. Can be realized. Although a heat sink can be provided on the heat exhaust substrate, if the housing is brought into direct contact with the heat exhaust substrate, the housing can be used as a heat sink, so that an inexpensive configuration can be obtained.

  Since heat dissipation is promoted in the present invention, the output can be higher than before (it can be brightened). Or, it is possible to extend the life with the same output as the conventional one. Furthermore, since a general metal material is used, it can be manufactured at low cost.

It is sectional drawing of the LED module apparatus which actualizes this invention. It is sectional drawing which shows the mounting board | substrate for one LED package. It is sectional drawing shown in the state which mounted the LED chip. It is a figure which illustrates the post electrode component by which the some post electrode was supported by the support plate. It is a figure which shows a post electrode component in the state connected on the LED package board | substrate with which the LED chip was mounted | worn. It is a figure shown in the state sealed with resin. (A) is a figure shown in the state after peeling a support plate, (B) is the top view, (C) It is a top view shown in the connected state. It is sectional drawing which shows the drilled secondary mounting board | substrate. It is a figure shown in the state which attached the LED package to the printed wiring board. It is sectional drawing shown in the state which attached the lens. (A) is a sectional view of the LED module device shown with a plate-shaped heat sink attached, (B) is a schematic bottom view seen from the X direction shown in (A), and (C) is from the Y direction. FIG. It is sectional drawing which shows another example of the printed wiring board (secondary mounting board | substrate) pierced. It is a figure shown in the state which mounted | wore the printed wiring board with the LED package. It is a figure shown in the state which attached the reflecting plate to the printed wiring board back surface It is sectional drawing shown in the state which attached the lens. It is sectional drawing shown in the state which attached the heat sink. (A) is a figure which shows the LED module comprised based on this invention (same as above-mentioned FIG. 11), (B) is a figure which shows a conventional structure. It is a figure which shows the example which applied the LED module apparatus of this invention to the lighting module used for exposure etc., (A) is with a heat sink, (B) is a housing | casing heat dissipation type, (C) is with a reflector. The case heat dissipation type is shown. It is a figure which shows the LED module provided with the thermal radiation apparatus by a prior art.

  Hereinafter, the present invention will be described based on examples. FIG. 1 is a cross-sectional view of an LED module device embodying the present invention. The illustrated LED module device is configured by connecting the post electrode of the assembled LED package and various circuit elements (see FIG. 9) to the wiring on the lower surface of the secondary mounting substrate (printed wiring board), and attaching a lens and a heat sink. . The LED package is configured by mounting an LED chip and a post electrode on an LED package substrate, connecting to a wiring layer on the substrate, and further sealing with a resin. The LED package is mounted on the secondary mounting substrate by connecting the opposite end of the post electrode connected to the wiring layer on the LED package substrate to the wiring on the lower surface of the secondary mounting substrate. The LED chip is arranged so that its light emitting surface faces the lens. However, it is desirable to mount the lens for collecting light, but the lens is not always necessary.

  Hereinafter, the manufacturing process of the LED module device illustrated in FIG. 1 will be described with reference to FIGS. FIG. 2 is a cross-sectional view showing a mounting substrate for one LED package. The LED package substrate uses a metal with good thermal conductivity, such as a single plate of aluminum or copper, for thermal diffusion or heat dissipation. A wiring layer is formed on the upper surface of the LED package substrate via an insulating layer. For example, a tape material with a copper foil is stuck on the LED package substrate. As a tape material with copper foil, a metal film having a low resistance to be a wiring pattern is deposited or pasted on the entire surface of the thin film tape to form a tape with metal. In the illustrated configuration, in order to improve heat dissipation, the insulating layer of the LED chip mounting portion in the center of the figure is cut off, and the back surface of the LED chip is electrically connected to the package and the heat sink. This is a case where one electrode is constituted by a post electrode and the other electrode is taken from the back surface of the chip. In this case, a heat sink is used as the ground electrode. However, in general, the ground electrode is often taken out from the same direction as the post electrode without taking out from the back surface of the chip. In this case, insulation is necessary. For example, the LED chip may be bonded using an insulating die-bonding material, or the tape on the entire surface of the LED package substrate may be left. As the thin film tape, an insulating base material of a thin film represented by a polyimide tape or the like is desirable. As the metal film, for example, gold, silver, copper, or palladium foil can be used. Alternatively, instead of vapor deposition or pasting a metal film, a thin film tape and a thin metal film (for example, copper foil) integrated may be used. Next, a wiring pattern is formed. In order to form a wiring pattern, a resist is applied on a metal layer (copper foil), the pattern is exposed and developed, and further etched, and the resist is removed to complete the wiring pattern. In a later step, a plurality of LED packages are assembled in a connected state until separation into individual substrates is performed.

  FIG. 3 is a cross-sectional view showing a state in which the LED chip is mounted. The LED chip has an LED light emitting surface on the upper surface, and a bonding wire connection electrode is formed around the LED light emitting surface. After fixing such an LED chip at a predetermined position on the LED package substrate, a wire bond connection is made between the wiring layer on the LED package substrate and the connection electrode of the LED chip by a bonding wire. Alternatively, it is also possible to provide a connection electrode of the LED chip on the lower surface and bond the LED chip and the LED package substrate with a die bond material such as Ag paste (flip chip bond connection).

  FIG. 4 is a diagram illustrating a post electrode component in which a plurality of post electrodes are supported by a support plate. This post electrode component itself can be produced by using a known technique as described in Patent Document 2. The illustrated post electrode component has a post electrode supported by a support plate. The post electrode and the support plate are formed by electroforming so that they can be easily peeled off by heat or pressure. As the plating metal of the conductive material grown by electroforming, for example, nickel or copper, a nickel alloy, or a material containing a copper alloy can be used. As the matrix material, for example, stainless steel can be used. Such a post electrode component forms a post electrode integrated with a support plate by growing the post electrode on a conductive material (electroformed mother die) as a support plate using lithography and plating. Alternatively, the post electrode may be formed by etching a metal clad material. In this case, the clad material is pasted on the support plate with a light release adhesive (peelable adhesive). For example, a copper layer for a post electrode and a thin nickel layer clad material as a stopper for etching the copper layer are used. In this way, by thinly laminating nickel as an etching stopper, it becomes possible to sharpen the post electrode shape and narrow the post electrode pitch. As will be described later, the support plate peeling step is performed after the resin sealing step. FIG. 4 illustrates only one post electrode component. However, in the same manner as the LED package substrate illustrated in FIG. 2, a plurality of components are used until separation into individual substrates is performed in a later step. It is assembled in a state where the pieces are connected.

  FIG. 5 is a view showing a state in which the post electrode component (see FIG. 4) is connected to the LED package substrate on which the LED chip is mounted. A post electrode of the post electrode component is fixed and electrically connected to a predetermined position (electrode pad portion) of the wiring layer formed on the upper surface of the LED package substrate. As a method for fixing and connecting the post electrodes, (1) ultrasonic bonding, (2) connection using a conductive paste such as silver paste, and (3) solder connection may be used.

  FIG. 6 is a diagram showing the resin-sealed state. After the post electrode integrally connected by the support plate is fixed at a predetermined position of the wiring layer on the LED package substrate, in this state, the upper surface of the LED package substrate on which the LED chip is mounted is the lower surface of the support plate. Or is resin-sealed using a liquid resin (material is, for example, epoxy).

  FIG. 7A is a view showing the state after the support plate is peeled off, and FIG. 7B is a top view thereof, and FIG. 7C is a top view showing the connected state. The support plate is peeled off by applying a predetermined temperature, for example. Then, after dividing | segmenting into an individual package, an LED package is attached to a secondary mounting board | substrate at the process shown below, and an LED module apparatus is comprised.

  FIG. 8 is a cross-sectional view showing the drilled secondary mounting substrate. As this secondary mounting board, a printed circuit board having a lens mounting portion perforated in advance is produced. Normally, a plurality of LED packages are attached to the secondary mounting substrate to constitute an LED module device (see FIG. 11). The printed wiring board is a single-layer wiring on one side, and the perforations are formed by punching a mold or the like in the state of a prepreg (resin-impregnated base material) or drilling. This secondary mounting board constitutes a printed wiring of a circuit pattern with a conductor such as copper foil on an insulating board. In the printed wiring, a conductor pattern is formed by printing on the surface or surface of an insulating substrate and the inside thereof in order to connect components.

  FIG. 9 is a diagram showing a state in which an LED package is mounted on a printed wiring board. The LED package is mounted by connecting the tip of the post electrode to the wiring (the electrode connection pad portion) provided on the secondary mounting substrate (printed wiring board) by soldering or the like. At this stage, not only the LED package but also electric circuit elements such as a control IC and a passive component are mounted and connected to the wiring provided on the printed wiring board.

  FIG. 10 is a sectional view showing the lens attached. The lens is attached to the perforated position of the printed wiring board using an adhesive. The light emitting surface of the LED chip faces the lens direction. Or you may attach to a printed wiring board in the state which mounted | wore the lens beforehand to the package.

  11A is a cross-sectional view of the LED module device shown with a plate-like heat sink attached, FIG. 11B is a schematic bottom view seen from the X direction shown in FIG. It is the schematic top view seen from the direction. As shown in the figure, a heat sink (for example, a heat sink such as a copper plate, an aluminum plate, or a mixed material of aluminum and carbon) is bonded to the LED package substrate. Thereby, the LED module device is completed. As a result, the heat generated from the LED chip is dissipated through the LED package substrate and further through the heat sink. Since a space is also formed between the heat sink and the printed wiring board, heat can be radiated not only from the upper surface in the figure of the heat sink but also from the lower surface thereof. However, as will be described later, instead of the heat sink, a housing in which the LED module device is mounted can be used as a heat sink. Note that FIG. 1 described above corresponds to an LED module device in which only one LED package is mounted.

  Next, another example of the LED module device will be described with reference to FIGS. FIG. 12 is a cross-sectional view showing another example of a printed wiring board (secondary mounting board) that has been perforated. As this secondary mounting board, a printed wiring board having a lens mounting portion perforated is produced in the same manner as in the above example (see FIG. 8). In the illustrated example, the lens mounting portion is tilted perforated and further reflected. A metal plating (for example, copper, nickel, etc.) is applied to the perforated part.

  FIG. 13 is a diagram showing a state in which an LED package is mounted on a printed wiring board. The LED package is mounted in the same manner as in the above example (see FIG. 9). Thereafter, as shown in FIG. 14, a reflection plate (for example, a metal plate) is attached to the back surface of the printed wiring board. Alternatively, the reflector can be mounted by plating using the same material as the metal plating shown in FIG.

  FIG. 15 is a sectional view showing the lens attached. Attach the lens to the drilling position of the secondary mounting board.

  FIG. 16 is a cross-sectional view showing a state in which a heat sink is attached. As illustrated, a heat sink (heat sink) is bonded to the LED package substrate. Thereby, the LED module device provided with the reflector is completed. As described above, the exemplary configuration can easily attach the reflection plate to the entire surface except for the lens portion, and thus, for example, when used in a lighting device, the overall luminous efficiency can be improved. Become.

  Next, the heat radiation action of the present invention will be described with reference to FIG. FIG. 17A is a diagram showing an LED module configured according to the present invention (same as FIG. 11 described above), and FIG. 17B is a diagram showing a conventional structure. As shown in the figure, the LED module device constructed according to the present invention separates a substrate for electrical connection (printed wiring board) and a substrate for exhaust heat (LED package substrate), and exhaust heat is the most cost effective. You can choose a good means. For example, a cheap aluminum or copper single plate can be used as the LED package substrate, and the housing can also be used as a heat sink. Further, by separating the printed wiring board and the heat exhaust plate (LED package substrate), the surface area of the heat exhaust plate is increased almost twice as compared with the conventional structure, thereby increasing the heat exhaust (radiation) effect.

  On the other hand, in the conventional structure, since the LED mounting substrate and the printed wiring board are integrated together or in combination, exhaust heat is limited, or the substrate is expensive because of the combination.

  18A and 18B are diagrams showing an example in which the LED module device of the present invention is applied to a lighting module used in a lighting device or the like. FIG. 18A shows a case with a heat sink, FIG. ) Shows the case heat radiation type with a reflector. As shown in FIG. 11, the LED module device itself has a heat sink as shown in FIG. 11A, and the lighting module is placed inside the case covered with light diffusion glass. This is a configured example.

  The housing heat radiation type shown in FIG. 18B does not have a heat sink in the LED module device itself, and heat radiation is performed using the housing.

  The housing heat radiation type with a reflector shown in FIG. 18C is provided with a reflector as shown in FIG. 16 in addition to the configuration shown in FIG.

As described above, the LED module device of the present invention can be independently molded with an LED chip, a printed wiring board surface mounted with a circuit element, a reflector mounting surface, and a heat dissipation (heat exhaust) surface. Good ability.

Claims (15)

In an LED module device in which an LED package having an LED chip mounted on an LED package substrate as a primary mounting substrate is mounted on a secondary mounting substrate,
In the LED package, the LED chip is mounted on the LED package substrate and connected to the wiring layer, and at least one post electrode is mounted on the wiring layer, and the wiring layer and the post electrode are mounted. It is configured by connecting one end of and sealing with resin,
Drilling the secondary mounting substrate, and mounting the LED package on the secondary mounting substrate so that the light emitting surface of the LED chip faces the drilling position,
The LED module device comprising: mounting the LED package on the secondary mounting substrate by connecting the other end of the post electrode to a wiring on the secondary mounting substrate. The LED module device according to claim 1, wherein a lens is attached to a perforation position of the secondary mounting substrate. The LED module device according to claim 2, wherein a printed wiring board having a single-sided single-layer wiring having a lens mounting portion perforated is used as the secondary mounting substrate. The LED module device according to claim 2, wherein a lens mounting portion is inclined and perforated on the secondary mounting substrate, and a reflective surface is formed on a surface opposite to the perforated portion and the LED package mounting surface. 2. The LED according to claim 1, wherein a metal plate having good thermal conductivity is used as the LED package substrate for thermal diffusion or heat dissipation, and the wiring layer is formed on the upper surface of the LED package substrate via an insulating layer. Modular device. 2. The LED module device according to claim 1, wherein the LED package is configured by collectively supporting the plurality of post electrodes on a support plate and peeling the support plate after resin sealing. The LED module device according to claim 1, wherein a circuit element including a control IC and a passive component is mounted and connected on the secondary mounting substrate. The LED module device according to claim 1, wherein a heat sink is attached to the LED package substrate on a side surface opposite to the LED chip mounting surface. The LED module device according to claim 8, wherein the heat sink is a ground electrode. In the manufacturing method of the LED module device in which the LED package having the LED chip mounted on the LED package substrate as the primary mounting substrate is mounted on the secondary mounting substrate,
A plurality of post electrodes are combined to constitute a post electrode component supported on a support plate,
In the LED package, the LED chip is mounted on the LED package substrate and connected to the wiring layer, and the post electrode component is mounted on the wiring layer on the LED package substrate. And one end of each of the post electrodes, and by separating the support plate after resin sealing,
Drilling the secondary mounting substrate, and mounting the LED package on the secondary mounting substrate so that the light emitting surface of the LED chip faces the drilling position,
The LED package is mounted on the secondary mounting board by connecting the other end of the post electrode to a wiring on the secondary mounting board. The manufacturing method of the LED module apparatus of Claim 10 which attached the lens to the drilling position of the said secondary mounting board | substrate. The manufacturing method of the LED module apparatus of Claim 11 using the printed wiring board of the single-sided single layer wiring which perforated the lens attachment part as said secondary mounting board | substrate. 12. The method of manufacturing an LED module device according to claim 11, wherein a lens mounting portion is inclined and perforated on the secondary mounting substrate, and a reflective surface is formed on a surface opposite to the perforated portion and the LED package mounting surface. . 11. The LED according to claim 10, wherein a metal plate having good thermal conductivity is used as the LED package substrate for heat diffusion or heat dissipation, and the wiring layer is formed on an upper surface of the LED package substrate via an insulating layer. A method for manufacturing a module device. The manufacturing method of the LED module apparatus of Claim 10 which attached the heat sink to the said LED package board | substrate on the opposite side to the LED chip mounting surface.

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