JP2007273602A - Wiring board for light emitting element, and light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiring board for use of a light emitting element capable of improving efficiency in extracting light, and to provide a light emitting device with a large light emission quantity. <P>SOLUTION: An element mounting part 6 for mounting the light emitting element 3 is provided on an insulative substrate 4. The mounting part 6 consists of an element mounting part body 19 to be placed on the substrate 4 and a protrusion 14 connecting with the body 19 and protruding in a tapered manner in the thickness direction Z from one surface 13 in the thickness direction Z of the substrate 4. The light emitting element 3 is mounted on a mounting surface 15 at the tip in the thickness direction Z of the protrusion 14 via a second joint 26. An area of the surface 15 is selected to be equal to an area of a packaging surface 20 facing the protrusion 14 of the element 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting element wiring board on which a light emitting element is provided and a light emitting device including the light emitting element wiring board.

  A light emitting device using a light emitting diode (abbreviated as LED) has a very high luminous efficiency and a small amount of heat generation compared to light emitting devices such as incandescent bulbs and fluorescent lamps. For example, there is an LED that has a very small size of about 0.1 mm in the width direction and a small heat generation amount that generates about 0.01 mW when the energization amount is about 30 mA (see, for example, Patent Document 1). In addition, as a container for housing the LED, there is a light emitting element housing package in which a convex portion protruding in the thickness direction from the surface of the substrate is formed (for example, see Patent Document 2). The convex portion has a placement portion on which a light emitting element is placed at a tip portion. On one surface portion in the thickness direction of the substrate, a wiring conductor connected to a predetermined terminal of the light emitting element by a bonding wire is formed. By differentiating the positions of the wiring conductor and the mounting part in the thickness direction of the substrate, it is possible to prevent the conductive adhesive from adhering to the wiring conductor when the light emitting element is attached to the mounting part. Undesirably conducting with the wiring conductor is prevented.

  Light emitting devices using LEDs have the advantage of being small and generating less heat, but they emit less light than light emitting devices such as incandescent bulbs and fluorescent lamps. It is used as the light source of the device.

  In view of increasing the luminance of a light-emitting device, there is a light-emitting device in which fluorescent particles are included in an adhesive for attaching a light-emitting element to a substrate (see, for example, Patent Document 3). By using the adhesive containing the fluorescent particles, the light emitted in the direction perpendicular to the light extraction direction of the light emitting device and the light emitted to the substrate side excite the fluorescent particles. The excited fluorescent particles convert the wavelength of light from the light emitting element and emit light in all directions. Accordingly, light other than light emitted in the light extraction direction is also used as light emitted from the light emitting device, and a light emitting device with high luminance is realized.

JP 2002-134790 A JP 2005-136123 A JP 2002-111073 A

  In the light emitting device of the prior art, since the light emission amount is not sufficient as an illumination device, there is a light emitting element wiring board capable of further increasing the light extraction efficiency from the light emitting device and a light emitting device with a large light emission amount. It has been demanded.

  In addition, when a light emitting element and a substrate are bonded using an adhesive containing fluorescent particles, it is necessary to use a resin having a lower thermal conductivity than a metal such as solder as the adhesive. There is a problem that the amount of light emission decreases as the temperature of the light emitting element increases.

  Accordingly, an object of the present invention is to provide a wiring board for a light emitting element and a light emitting device having a large light emission amount that can increase the light extraction efficiency.

The present invention has electrical insulation and a substrate on which wiring is formed;
An element mounting portion on which a mounting surface for mounting a light emitting element is formed at a tip portion that is inclined farthest from the one surface as the outer peripheral surface protrudes from one surface in the thickness direction of the substrate; It is a wiring board for light emitting elements characterized by including.

  Further, the present invention is characterized in that the area of the mounting surface is selected to be equal to the area of the mounting surface facing the element mounting portion of the light emitting element.

According to the present invention, the element mounting portion is made of metal.
In the invention, it is preferable that the element mounting portion is provided on the substrate through the substrate in the thickness direction.

In the invention, it is preferable that the element mounting portion is made of copper or aluminum.
Further, the present invention is characterized in that it further includes a reflective film formed on the outer peripheral surface of the element mounting portion between the mounting surface and the one surface, and made of silver or aluminum.

  Further, the present invention is characterized in that the light emitting element mounted on the mounting surface and a frame portion surrounding the element mounting portion are further included on one surface of the substrate.

The present invention also provides the light emitting element wiring board;
A light emitting device mounted on the mounting surface;
A light emitting device comprising: the wiring formed on the substrate; and an element connecting portion for connecting the light emitting elements.

  In addition, the present invention is characterized in that it further has a light-transmitting property and further includes a covering portion that covers the light-emitting element.

  According to the present invention, the outer peripheral surface of the element mounting portion is inclined in a direction approaching each other as it protrudes from one surface in the thickness direction of the substrate. A mounting surface on which the light emitting element is mounted is formed at the tip portion farthest from the substrate of the element mounting portion. The light emitting element mounted on the mounting surface not only emits light in the light extraction direction opposite to the substrate side, but also emits light toward the substrate side. At least a portion of the light emitted from the light emitting element to the substrate side is incident on and reflected from the outer peripheral surface of the element mounting portion between the mounting surface and one surface of the substrate, and is opposite to the substrate side from the light emitting element. Light is taken out. If the element mounting portion is formed in a quadrangular prism or columnar shape, light is not reflected on the outer peripheral surface of the element mounting portion, so that light emitted from the light emitting element to the substrate side is not used. Accordingly, the outer peripheral surface of the element mounting portion is inclined and the element mounting portion is formed in a tapered shape, thereby realizing a light emitting element wiring board having a higher light extraction efficiency than the columnar element mounting portion. .

  In addition, since light emitted from the light emitting element is reflected or scattered at various parts, when the outer peripheral surface of the element mounting portion is formed perpendicular to the surface of the substrate, the outer peripheral surface The light incident on the substrate is reflected on one surface in the thickness direction of the substrate and is lost, whereas the outer peripheral surface of the element mounting portion is formed at an angle and reflected on the conventional substrate side. Even with such light, the light can be guided to the side or the front side opposite to the substrate by the outer peripheral surface having an angle, and a light-emitting element wiring substrate with high light extraction efficiency is realized.

  The incident angle of the light emitted from the light emitting element to the outer peripheral surface is larger than the incident angle to the plane when the light emitting element is mounted on a plane having a larger area than the light emitting element. Since at least S-polarized light has a higher reflectance as the incident angle increases, reflection of light emitted from the light emitting element to the substrate side is more improved when the element mounting portion is provided than when a light emitting element is mounted on a flat surface. The rate is high. Therefore, the light emitted to the substrate side can be used more effectively as the extracted light, and a light emitting element wiring board with high light extraction efficiency is realized.

  According to the invention, the area of the mounting surface is equal to the area of the mounting surface facing the element mounting portion of the light emitting element. When the area of the mounting surface is smaller than the area of the mounting surface of the light emitting element, the area of the joint portion between the element mounting portion and the light emitting element is reduced. In this case, the amount of heat generated in the light emitting element is not easily diffused through the element mounting portion. Since the luminous efficiency of the light emitting element decreases as the temperature rises, the luminous efficiency of the light emitting element decreases when the area of the mounting surface is smaller than the area of the mounting surface of the light emitting element. In addition, when the area of the mounting surface is smaller than the area of the mounting surface of the light emitting element, the area of the bonding portion between the light emitting element and the mounting surface is reduced, so that the bonding property between the light emitting element and the mounting surface is deteriorated. Further, if the area of the mounting surface is larger than the area of the mounting surface of the light emitting element, a part of light emitted from the light emitting element to the substrate side enters the mounting surface. In this case, since the mounting surface performs the same operation as the plane in the configuration in which the light emitting element is mounted on the plane, the light extraction efficiency is lowered. In the present invention, since the area of the mounting surface is equal to the area of the mounting surface of the light emitting element, the light emitting element has high heat dissipation, high light extraction efficiency, and good light emitting element and mounting surface bonding characteristics. A wiring board is realized.

  According to the present invention, since the element mounting portion is made of a metal having higher thermal conductivity than resin and ceramics, the amount of heat generated in the light emitting element can be efficiently diffused to the element mounting portion. This realizes a light emitting element wiring board that suppresses the temperature rise of the light emitting element and increases the light emission efficiency.

  Further, according to the present invention, since the element mounting portion penetrates the thickness direction of the substrate, the heat generated in the light emitting element is conducted from the other surface side in the thickness direction of the substrate through the element mounting portion. . This realizes a light emitting element wiring board that suppresses the temperature rise of the light emitting element and increases the light emission efficiency.

  In addition, according to the present invention, since the element mounting portion is inexpensive among metals, has high thermal conductivity, and is ready for processing, use of copper or aluminum suppresses the temperature rise of the light emitting element, and emits light. A wiring board for a light emitting element with high efficiency is realized.

  Further, according to the present invention, since the reflective film made of silver or aluminum having a high reflectance is formed on the outer peripheral surface of the element mounting portion, the light emitted from the light emitting element to the substrate side is reflected by the reflective film. The proportion of light that goes up increases. As a result, a light emitting element wiring board with high light extraction efficiency is realized.

  According to the invention, the light emitting element mounted on the mounting surface and the frame portion surrounding the element mounting portion are formed. By this frame portion, for example, an obstacle and a light emitting element can be prevented from colliding with each other, and the light emitting element is protected. For example, when the light emitting element is surrounded by a phosphor, the frame and the substrate function as a container, so that the phosphor can be easily filled in the container, and the light emitting element surrounds the light emitting element. The device can be easily manufactured.

  Further, according to the present invention, since the light emitting device is configured using the light emitting element wiring substrate capable of increasing the light extraction efficiency as described above, a light emitting device having a large light emission amount can be realized.

  According to the present invention, since the covering portion covers the light emitting element, the light emitting element can be protected from moisture and dust. Further, since the covering portion has translucency, light from the light emitting element is not absorbed by the covering portion. As a result, a light emitting device having a large light emission amount can be realized.

  FIG. 1 is a cross-sectional view showing a light emitting device 1 according to an embodiment of the present invention. FIG. 2 is a plan view of the light emitting device 1. The light emitting device 1 includes a light emitting element wiring substrate 2 and a light emitting element 3. The light emitting element wiring board 2 functions as a container for housing the light emitting element 3. In the present embodiment, the light emitting element 3 is realized by an LED chip configured to include a light emitting diode (abbreviated as LED).

  The light emitting element wiring board 2 includes an electrically insulating substrate 4, wiring 5 formed on the substrate 4, an element mounting portion 6 on which the light emitting element 3 is mounted, and a frame portion 7 surrounding the light emitting element 3. Consists of including.

  The substrate 4 is formed in a plate shape in the present embodiment, and is formed so that a cross section perpendicular to the thickness direction is a square. The substrate 4 is white. Since the board | substrate 4 is white, a reflectance becomes high with respect to the light from the light emitting element 3 to mount. Thereby, the light incident on the substrate 4 from the light emitting element 3 is reflected in the light extraction direction, and the light from the light emitting element 3 can be used efficiently. Henceforth, the thickness direction of the board | substrate 4 is described as the thickness direction Z, the width direction of the board | substrate 4 is described as the 1st width direction X, and the width direction of the board | substrate 4 perpendicular | vertical to the 1st width direction X and the thickness direction Z is 2nd. It may be described as the width direction Y.

  A first through hole 8 that penetrates the substrate 4 in the thickness direction Z is formed in the center of the substrate 4 in the first width direction X and the second width direction Y. An element mounting portion 6 is provided in the first through hole 8. Further, a second through hole 10 penetrating the substrate 4 in the thickness direction Z is formed at a portion near the first through hole 8 between the first through hole 8 and one end of the substrate 4 in the second width direction Y. Is done. The second through hole 10 is provided with a first through electrode 9 described later. Further, a third through hole 12 that penetrates the substrate 4 in the thickness direction Z is formed at a portion near the first through hole 8 at the other end of the first through hole 8 and the substrate 4 in the second width direction Y. . The third through hole 12 is provided with a second through electrode 11 described later. In the present embodiment, the substrate 4 is made of a ceramic having a higher thermal conductivity than the resin. Thereby, the heat dissipation of the light emitting element 3 can be improved.

  The element mounting portion 6 is provided on the substrate 4 through the substrate 4 in the thickness direction Z of the substrate 4. The element mounting portion 6 is bonded to the substrate 4 via a first bonding portion 16 formed on the inner peripheral surface facing the first through hole 8 of the substrate 4. The element mounting portion 6 includes an element mounting portion main body 19 disposed in the first through-hole 8, and an outer peripheral surface 17 connected to the element mounting portion main body 19 in the thickness direction Z from one surface 13 of the thickness direction Z of the substrate 4. On the other hand, the projection 14 is inclined in a direction approaching each other as it projects in Z1. Protruding from one surface 13 in the thickness direction Z of the substrate 4 specifically means projecting from a virtual plane including the one surface 13 in the thickness direction Z of the substrate 4. Note that the element mounting portion 6 may be formed integrally with the same member as the substrate 4, and a protrusion 14 made of a material different from the substrate 4 is disposed on the surface of the plate-like substrate 4. Also good. In the present embodiment, the element mounting portion main body 19 and the protruding portion 14 are formed in a square truncated cone shape, and are formed so as to be tapered toward one side Z1 in the thickness direction Z. The inclination angle of the outer peripheral surface of the element mounting portion main body 19 with respect to the thickness direction Z is smaller than the inclination angle θ of the outer peripheral surface 17 of the protrusion 14 with respect to the thickness direction Z. Thus, since the element mounting part main body 19 is formed in the shape of a square pan, the element mounting part main body 19 is easily fitted into a predetermined position of the first through hole 8. Thus, the element mounting portion 6 can be easily incorporated into the substrate 4. The mounting surface 15 formed at the tip end portion of the element mounting portion 6 in the thickness direction Z on one side Z1, that is, the mounting surface 15 formed at the tip end portion of the projection portion 14 in the thickness direction Z on one side Z1 is perpendicular to the thickness direction Z. Formed on a flat surface. In the present embodiment, the mounting surface 15 is formed to be a square, and each side is formed in parallel to the first width direction X or the second width direction Y, respectively. In the present embodiment, the cross section of the element mounting portion 6 in a virtual plane including the one surface 13 in the thickness direction Z of the substrate 4 is formed in a square larger than the mounting surface 15 and each side is in the first width direction X. Or it forms in parallel with the 2nd width direction Y, respectively. In the present embodiment, the outer peripheral surface 17 of the protrusion 14 between the mounting surface 15 of the protrusion 14 and a virtual plane including the one surface 13 of the substrate 4 in the thickness direction Z is formed in a planar shape. The element mounting portion 6 is formed using a material having a thermal conductivity higher than that of at least the substrate 4. Thereby, the heat dissipation of the light emitting element 3 can be improved.

On the surface of the element mounting portion 6, a reflective film 18 having a high reflectance with respect to the wavelength of light emitted from the light emitting element 3 is formed. The reflective film 18 is composed of a single layer or a plurality of layers. In the reflective film 18, the layer farthest from the element mounting portion 6 is made of, for example, Al ₂ O ₃ , Al, or Ag. When the layer of the reflective film 18 that is farthest from the element mounting portion 6 is made of Al ₂ O ₃ , the reflectance is about 70%, and when it is made of Al, the reflectance is 75% to 90%. In the case of Ag, the reflectance is 90 to 95%. Further, the reflective film 18 has a layer made of Ni and a layer made of Au in order to improve the adhesion between the reflective film 18 and the element mounting part 6 and to prevent discoloration of the layer made of Ag. , Ag layers may be laminated in this order. The reflective film 18 is formed using, for example, a plating method.

  The mounting surface 15 is preferably formed in substantially the same shape as the mounting surface 20 facing the protrusion 14 of the light emitting element 3. More preferably, the mounting surface 15 is formed in the same shape as the mounting surface 20 of the light emitting element 3. That is, the area of the mounting surface 15 is more preferably selected equal to the mounting surface 20 of the light emitting element 3.

  The wiring 5 is formed using a conductive material. The wiring 5 includes a first through electrode 9, a second through electrode 11, a first surface pad electrode 21, a second surface pad electrode 22, a first back pad electrode 23, and a second back pad electrode 24. Consists of including.

  The first through electrode 9 is formed in the second through hole 10 of the substrate 4. The first surface pad electrode 21 is formed on one surface 13 of the thickness direction Z of the substrate 4 so as to cover one surface of the thickness direction Z of the first through electrode 9. The first back surface pad electrode 23 is formed on the other surface 25 of the thickness direction Z of the substrate 4 so as to cover the surface of the other through Z2 of the first through electrode 9 in the thickness direction Z. The first front surface pad electrode 21, the first through electrode 9, and the first back surface pad electrode 23 are electrically connected.

  The second through electrode 11 is formed in the third through hole 12. The second surface pad electrode 22 is formed on the one surface 13 of the thickness direction Z of the substrate 4 so as to cover one surface of the thickness direction Z of the second through electrode 11. The second back surface pad electrode 24 is formed on the other surface 25 of the thickness direction Z of the substrate 4 so as to cover the other surface of the second through electrode 11 in the thickness direction Z. The second front surface pad electrode 22, the second through electrode 11, and the second back surface pad electrode 24 are electrically connected.

  The light emitting element 3 is mounted on the mounting surface 15 via the second joint portion 26. The light emitting element 3 has a plate shape in the present embodiment, and a cross section perpendicular to the thickness direction Z is formed in a square shape. The shape of the mounting surface 20 facing the protrusion 14 of the light emitting element 3 is equal to the shape of the mounting surface 15 in the present embodiment. The light emitting element 3 is mounted on the mounting surface 15 so that the mounting surface 15 and the mounting surface 20 of the light emitting element 3 coincide with each other when viewed from one side in the thickness direction Z.

  The light emitting device 1 further includes a bonding wire 27 corresponding to the element connecting portion. Either one of the anode and the cathode of the light emitting element 3 is connected to the first surface pad electrode 21 via the bonding wire 27, and the other of the anode and the cathode is connected to the second surface pad electrode 22 via the bonding wire 27. Connected to. Accordingly, one of the anode and the cathode of the light emitting element 3 is electrically connected to the first back surface pad electrode 23, and the other of the anode and the cathode is electrically connected to the second back surface pad electrode 24. As a result, electric power can be supplied from the outside of the light emitting device 1 to the light emitting element 3 via the first and second back surface pad electrodes 23 and 24, and the light emitting element 3 can emit light.

  The frame portion 7 is formed on the peripheral portion of the one surface 13 of the thickness direction Z of the substrate 4 so as to extend in parallel with one Z1 of the thickness direction Z via the third joint portion 28. The frame portion 7 is formed so as to extend at least one surface Z1 in the thickness direction Z from one surface 29 in the thickness direction Z of the light emitting element 3, and surrounds the light emitting element 3 and the protrusion 14 mounted on the mounting surface 15. In the present embodiment, the inner circumference of the cross section perpendicular to the thickness direction Z of the frame portion 7 is formed to be a square. Further, the inner peripheral surface of the frame portion 7 is formed in a planar shape parallel to the thickness direction Z in the present embodiment.

  The light emitting device 1 further includes a covering portion 31 formed using a material having translucency at the wavelength of light from the light emitting element 3. The covering portion 31 is formed by filling a region surrounded by the frame portion 7 with resin or the like. The covering portion 31 is formed such that the position of the surface 32 of the one Z1 in the thickness direction Z is equal to the position of the surface 33 of the one Z1 in the thickness direction Z of the frame portion 7.

  The dimension of each member of the light emitting device 1 is selected so that the light emitted from the light emitting element 3 can be extracted most efficiently and the amount of heat generated in the light emitting element 3 can be radiated most efficiently. . The inclination angle θ from the thickness direction Z of the outer peripheral surface 17 of the protrusion 14 greatly affects the light extraction efficiency of the light emitting element 3 and is selected from 20 ° to 70 °, more preferably from 30 ° to 60 °. It is. The dimension H1 in the thickness direction Z of the protrusion 14 greatly affects the light extraction efficiency of the light-emitting element 3 in the same manner as the inclination angle θ, and the dimension H2 in the thickness direction Z of the light-emitting element 3 and the thickness of the second joint portion 26. It is set based on the dimension H3 in the direction Z. The dimension H3 in the thickness direction Z of the second joint portion 26 is selected to be about 5 μm. The dimension H1 in the thickness direction Z of the protrusion 14 is selected to be 1 to 5 times (H2 + H3), for example, 0.1 mm to 0.5 mm. The dimension H4 in the thickness direction Z of the first and second surface pad electrodes 21 and 22 needs to be thin enough not to affect the light emitted from the light emitting element 3 and thick enough not to increase the electrical resistance. For example, it is selected to be about 1/10 to 1/20 of the dimension H1 of the protrusion 14 in the thickness direction Z, and is selected to be 0.01 mm to 0.02 mm. The dimension W1 between the surfaces of the frame part 7 facing each other and the dimension H5 in the thickness direction Z of the frame part 7 greatly affect the light emission angle of the light emitting device 1. For example, when reducing the radiation angle, the dimension W1 is set small and the dimension H5 is set large. The dimension W1 and the dimension H5 are the dimension D1 of the light emitting element 3 in the first width direction X, the dimension W2 of the light emitting element 3 in the second width direction Y, and the substrate 4 on the one surface 29 of the light emitting element 3 in the thickness direction Z. It is set based on the distance (H1 + H2 + H3) from one surface 13 in the thickness direction Z. The dimension W1 is selected to be 3 to 5 times the dimension W2, for example, and is selected to be 2 mm to 4 mm. The dimension H5 is selected to be 2 to 5 times the dimension (H1 + H2 + H3), and is selected to be 0.2 to 0.5 mm.

Next, a method for manufacturing the light emitting device 1 will be described.
In the present embodiment, the substrate 4 is made of ceramics whose main crystal phase is Al ₂ O ₃ , MgO, SiO ₂ , CaO, AlN, Si ₃ N ₄ or the like.

When the substrate 4 is produced using an Al ₂ O ₃ sintered body having Al ₂ O ₃ as a main crystal phase, an inexpensive raw material can be used, so that an inexpensive wiring substrate 2 for a light emitting element is obtained. Can do. The Al ₂ O ₃ and _Al 2 _{O 3} quality sintered body composed mainly crystalline phase, for example, in the structure analysis using X-ray diffraction, is like the peak of _Al 2 _{O 3} is detected as the main peak It is desirable to contain 50% by volume or more of Al ₂ O ₃ crystals as a volume ratio.

In order to form the substrate 4 made of alumina (Al ₂ O ₃ ) ceramic, first, Al having an average particle diameter of 0.1 μm to 8 μm, preferably an average particle diameter of 1.0 μm to 2.0 μm and a purity of 99% by mass or more. ₂ O ₃ powder, at least one sintering aid selected from the group consisting of Mn ₂ O ₃ , SiO ₂ , MgO, SrO, and CaO having an average particle size of 1.0 μm to 2.0 μm, and an organic resin for molding (Binder) is mixed with toluene as a solvent to prepare a mud-like viscous material called slurry. The addition amount of the composition, such as sintering aid excluding Al ₂ O _3, in order to obtain a dense body of the _Al 2 _{O 3} as a main crystal, preferably 15 wt% or less, more preferably 10 wt% or less Is desirable. In particular, when the addition amount of a composition such as a sintering aid other than Al ₂ O ₃ is 15% by mass or less, most of the obtained substrate 4 can be formed of Al ₂ O ₃ crystals. The amount of these sintering aids added is preferably 5% by mass or more, more preferably 7% by mass or more in order to lower the firing temperature.

  The slurry thus prepared is molded into a predetermined shape using a doctor blade method to form a ceramic molded body called a ceramic green sheet.

  Next, the first to third through holes 8, 10, 12 are formed by punching the ceramic green sheet. Next, the 2nd and 3rd through-holes 10 and 12 are filled with the electrically conductive paste containing the powder which consists of material which has electroconductivity. Further, the conductive paste is printed on the portions where the first and second front surface pad electrodes 21 and 22 and the first and second back surface pad electrodes 23 and 24 are to be formed. The powder is composed of molybdenum (Mo), tungsten (W), or the like that does not melt during firing, which will be described later.

  Next, the ceramic green sheet coated with the conductive paste is fired in a temperature range of 1300 ° C. to 1600 ° C. in an oxidizing atmosphere, a reducing atmosphere, or an inert atmosphere. Thus, the substrate 4 is formed, and the first and second through electrodes 9 and 11, the first and second surface pad electrodes 21 and 22, and the first and second back surface pad electrodes 23 and 24 are formed. The first and second front surface pad electrodes 21, 22 and the first and second back surface pad electrodes 23, 24 are formed on the surface of the substrate 4 using a thin film method, or the metal foil is transferred to the surface of the molded body. Or may be formed.

  The ceramic substrate has high rigidity, is not deteriorated by light or heat emitted from the light emitting element 3, and has a relatively high thermal conductivity material, so that the ceramic substrate becomes a high performance and long life wiring substrate 2 for the light emitting element.

In the case of ceramics having main crystal phases such as MgO, SiO ₂ , CaO, AlN, and Si ₃ N ₄ , the firing temperature is different, but the substrate 4 made of ceramics having Al ₂ O ₃ as the main crystal phase is used. The substrate 4 can be formed through substantially the same procedure as the forming procedure. When a low-temperature fired ceramic substrate, a so-called glass ceramic substrate, is used as the substrate 4, the thermal conductivity, strength, and rigidity are inferior to ceramics fired in a temperature range of 1050 ° C. or higher, such as alumina ceramics. Since the expansion coefficient can be easily controlled, it is possible to easily match the thermal expansion coefficient with the element mounting portion 6. Further, in the case of glass ceramics having MgO, SiO _2, CaO or the like as the main crystal phase, since it can be fired at a temperature lower than the firing temperature of alumina (Al ₂ O ₃ ) ceramics, copper and silver having a low melting point The first and second through electrodes 9 and 11, the first and second surface pad electrodes 21 and 22, and the first and second back surface pad electrodes 23 and 24 made of a metal having a low resistivity can be fired simultaneously. it can. As a result, the low resistance wiring 5 can be formed, and electrical loss and heat generation in the wiring 5 can be suppressed.

  Next, the element mounting portion 6 is inserted into the first through hole 8, and the substrate 4 and the element mounting portion 6 are bonded via the first bonding portion 16. The element mounting portion 6 is formed, for example, by punching a metal plate or metal foil made of metal with a press machine or the like. The element mounting portion 6 is made of, for example, copper (Cu) or aluminum (Al) having a high thermal conductivity. Since Cu and Al are inexpensive, the light emitting device 1 can be manufactured at low cost. The element mounting portion 6 can be formed by a processing method such as pressing, casting, polishing, and powder metallurgy. Thereby, the element mounting portion 6 having a complicated shape can be formed. Further, the element mounting portion 6 may be formed using another processing method different from the method described above.

  The 1st junction part 16 consists of at least 1 sort (s) chosen from the group of a metal, ceramics, and resin. The first joint portion 16 is realized by, for example, a metal having a low melting point, and is realized by, for example, tin 60 mass% to 10 mass% -lead 40 mass% to 90 mass% solder, or lead-free solder not containing lead. By using the solder having a low melting point as described above, the operation of the bonding process for bonding the substrate 4 and the element mounting portion 6 can be easily performed.

  When a metal is used for the first joint portion 16, it is necessary to form a metal layer in advance on the inner peripheral surface facing the first through hole 8 of the substrate 4 in order to improve wettability with the first joint portion 16. There is. In the case of using solder, the substrate 4 and the element mounting portion 6 can be joined by processing for 10 seconds in a reflow furnace in a nitrogen atmosphere at 230 ° C.

  In addition to the solder, for example, eutectic Ag brazing material is used, and the substrate 4 and the element mounting portion 6 can be joined by processing in a reflow furnace in a mixed atmosphere of nitrogen and hydrogen at 800 ° C. for 1 hour. .

Moreover, the board | substrate 4 and the element mounting part 6 can also be joined using what is called an active metal method.
Moreover, when using resin as the 1st junction part 16, it is desirable to use the epoxy resin type | system | group joining agent generally used. When using a resin, the bonding agent is cured by heating for 20 to 40 minutes, for example, in an atmosphere of 80 to 150 ° C. according to the curing temperature of the bonding agent, and the substrate 4 and the element mounting portion via the first bonding portion 16. 6 can be joined.

  Bonding using a resin is superior to bonding using a metal in that it is inexpensive and can be easily bonded. In particular, when the substrate 4 is formed using a resin, the bonding force between the substrate 4 and the element mounting portion 6 increases when the resin is used as a bonding material. Further, when a resin is used as a bonding material, the bonding process can be performed at a relatively low temperature, so that there is almost no damage to the substrate 4, and the interface between the first bonding portion 16 and the substrate mounting portion 6 and the element mounting portion 6 are not affected. Generation of cracks can be prevented, and a highly reliable light emitting element wiring substrate 2 can be manufactured.

  Moreover, when using ceramics as the 1st junction part 16, low melting glass ceramics are used, for example. By using such a low-melting glass ceramic, the substrate 4 and the element mounting portion 6 can be bonded at a relatively low temperature of 600 ° C. or less, and the thermal stress generated by the bonding can be reduced.

  Moreover, you may form the 1st junction part 16 using the material which compounded the metal, ceramics, and resin. For example, by mixing metal powder, ceramic powder, and resin in an appropriate ratio, the thermal expansion coefficient of the first joint portion 16 can be adjusted according to the thermal expansion coefficients of the substrate 4 and the element mounting portion 6. Sometimes the stress that occurs can be reduced.

  The frame portion 7 is formed using a metal such as Al or Fe—Ni—Co alloy, and is connected to the substrate 4 via the third bonding portion 28. The third joint portion 28 is formed in the same manner as the first joint portion 16 described above. Since the frame portion 7 is formed of a metal that can be easily formed at low cost, even the frame portion 7 having a complicated shape can be easily and inexpensively formed. Can be manufactured. When the reflectance of the surface of the frame part 7 is low, a reflective film having a high reflectance is formed on the surface of the frame part 7 in the same manner as the reflective film 18 described above.

  Next, the light emitting element 3 is bonded to the mounting surface 15 of the element mounting portion 6 via the second bonding portion 26. The second bonding portion 26 is formed by curing the bonding agent, and is realized by an Au—Sn brazing material, an epoxy resin, or the like. When the light emitting element 3 is bonded using the Au—Sn brazing material, the second bonding portion 26 having high thermal conductivity is realized. In this case, since the amount of heat generated in the light emitting element 3 is efficiently diffused to the element mounting portion 6 via the second joint portion 26, the heat dissipation of the light emitting element 3 is improved. Therefore, the heat dissipation of the light emitting element 3 can be improved as compared with the conventional light emitting device in which the light emitting element 3 is bonded using an adhesive containing a phosphor, and the amount of light emission is reduced by the heat generated by the light emitting element 3. Can be prevented.

  When the light emitting element 3 is attached, the light emitting element 3 and the wiring 5 are then electrically connected by the bonding wire 27. Next, a coating part 31 is formed by filling an epoxy resin in a space surrounded by the light emitting element wiring substrate 2 and curing it. Thus, since the light emitting element 3 is attached to the element mounting portion 6 made of a metal having a high thermal conductivity, the amount of heat generated in the light emitting element 3 can be efficiently diffused to the element mounting portion 6 and generated in the light emitting element 3. It is possible to efficiently dissipate the amount of heat. Further, the amount of heat dissipated from the light emitting element 3 to the element mounting portion 6 is diffused into the frame portion 7 made of air, the substrate 4 and a metal having a high thermal conductivity, so that the amount of heat generated in the light emitting element 3 is efficiently dissipated. be able to. Accordingly, it is possible to suppress a decrease in luminance of the light emitting element 3 due to heat generation. Further, since it is not necessary to further provide a heat radiating member such as a heat sink, the light emitting device 1 can be downsized and the light emitting device 1 can be manufactured at low cost.

  According to the light emitting device 1 of the present embodiment described above, the protruding portion 14 is formed so as to project from the one surface 13 of the thickness direction Z of the substrate 4 to one side Z1 in the thickness direction Z. The light emitting element 3 emits light not only in the light extraction direction Z1 in the thickness direction Z but also on the substrate 4 side. At least a part of the light emitted from the light emitting element 3 to the substrate 4 side is incident on and reflected by the reflection film 18 formed on the outer peripheral surface 17 of the protrusion 14, and the light is extracted in the light extraction direction. If the element mounting portion is formed in a quadrangular prism shape or a cylindrical shape, light is not reflected on the outer peripheral surface of the element mounting portion, and thus light emitted from the light emitting element to the substrate side is not used. Therefore, by forming the protrusions 14 in a tapered shape, the light emitting element wiring board 2 having a higher light extraction efficiency than that of the element mounting portion formed in a columnar shape is realized.

  In addition, since light emitted from the light emitting element 3 is reflected or scattered at various portions, when the outer peripheral surface 17 of the protrusion 14 is formed perpendicular to the substrate 4, The light incident on the surface 17 is reflected on the one surface 13 in the thickness direction Z of the substrate 4 and lost, whereas the outer peripheral surface 17 of the protrusion 14 is formed at an angle to form a conventional substrate. Even if the light is reflected to the side, the light can be guided to the direction perpendicular to the thickness direction Z or the front side opposite to the substrate 4 by the outer peripheral surface 17 having an angle. A highly efficient light-emitting element wiring board 2 is realized.

  The incident angle of the light emitted from the light emitting element 3 to the reflection film 18 is larger than the incident angle to this plane when the light emitting element 3 is mounted on a plane wider than the light emitting element 3. Since at least the S-polarized light has a higher reflectance as the incident angle increases, light emitted from the light emitting element to the substrate 4 side is more provided with the protrusion 14 than when the light emitting element 3 is mounted on a plane. The reflectance becomes higher. Therefore, the light emitted to the substrate 4 side can be used more effectively as extracted light, and the light emitting element wiring substrate 2 with high light extraction efficiency is realized.

  In particular, the inclination angle θ from the thickness direction Z of the outer peripheral surface 17 of the protrusion 14 is selected from 30 ° to 60 °, and the dimension H1 of the protrusion 14 in the thickness direction Z is 1 to 5 times (H2 + H3). Therefore, the reflection film 18 effectively functions as a film that reflects light, and the light extraction efficiency is increased.

  In addition, since the reflective film 18 having a higher reflectance than the surface of the element mounting portion 6 is formed on the outer peripheral surface 17 of the protrusion 14, the light emitted from the light emitting element 3 to the substrate 4 side can be reflected more. . Thereby, the light extraction efficiency of the light emitting device 1 can be increased. Moreover, by forming the reflective film 18, the element mounting portion 6 can be prevented from corrosion.

  Further, the area of the mounting surface 15 of the light emitting device 1 according to the present embodiment is equal to the area of the mounting surface 20 facing the protruding portion 14 of the light emitting element 3. When the area of the mounting surface 15 is smaller than the area of the mounting surface 20 of the light emitting element 3, the area of the joint portion between the element mounting portion 6 and the light emitting element 3 becomes small. In this case, the amount of heat generated in the light emitting element 3 is not easily diffused through the element mounting portion 6. Since the luminous efficiency of the light emitting element 3 decreases as the temperature rises, the luminous efficiency of the light emitting element 3 decreases when the area of the mounting surface 15 is smaller than the area of the mounting surface 20 of the light emitting element 3 as described above. In addition, when the area of the mounting surface 15 is smaller than the area of the mounting surface 20 of the light emitting element 3, the area of the joint portion between the light emitting element 3 and the mounting surface 15 becomes small, and thus the bonding property between the light emitting element 3 and the mounting surface 15. Decreases. If the area of the mounting surface 15 is larger than the area of the mounting surface 20 of the light emitting element, a part of the light emitted from the light emitting element 3 to the substrate 4 side enters the mounting surface 15. In this case, since the mounting surface 15 performs the same operation as the plane in the configuration in which the light emitting element 3 is mounted on the plane, the light extraction efficiency is lowered. In the present embodiment, the area of the mounting surface 15 is equal to the area of the mounting surface 20 of the light emitting element 3, so that the light emitting element 3 has high heat dissipation, high light extraction efficiency, and the light emitting element 3 and the mounting surface 15. The light emitting element wiring board 2 with good bonding property is realized.

  Further, the element mounting portion 6 of the light emitting device 1 of the present embodiment is made of a metal having higher thermal conductivity than resin and ceramics. In particular, since the element mounting portion 6 is made of copper or aluminum, the amount of heat generated in the light emitting element 3 can be efficiently diffused into the element mounting portion 6. As a result, the light emitting element wiring board 2 is realized in which the temperature rise of the light emitting element 3 is suppressed and the light emission efficiency is increased.

  In addition, since the element mounting portion 6 of the light emitting device 1 according to the present embodiment penetrates the thickness direction Z of the substrate 4, the amount of heat generated in the light emitting element 3 is conducted through the element mounting portion 6 and the thickness direction of the substrate 4. Heat is also radiated from the other surface 25 side. As a result, the light emitting element wiring board 2 is realized in which the temperature rise of the light emitting element 3 is suppressed and the light emission efficiency is increased.

  Further, in the light emitting device 1 of the present embodiment, the frame portion 7 surrounding the light emitting element 3 and the protruding portion 14 is formed around an axis extending in parallel with the thickness direction Z. The frame portion 7 can prevent, for example, an obstacle and the light emitting element 3 from colliding with each other, and the light emitting element 3 is protected. Further, when forming the covering portion 31, the frame portion 7 and the substrate 4 function as a container for filling the material of the covering portion 31, so that the covering portion 31 can be easily formed. Further, since a reflective film having a high reflectance is formed on the frame portion 7, light is reflected by the frame portion 7. Thereby, the light from the light emitting element 3 can be collected in the light extraction direction, and the light emitting element wiring board 2 with high light extraction efficiency is realized.

  Moreover, since the light emitting device 1 according to the present embodiment includes the covering portion 31 that covers the light emitting element 3, the light emitting element 3 can be protected from moisture and dust. Since the covering portion 31 has translucency, the light from the light emitting element 3 is not absorbed by the covering portion 31. As a result, the light emitting device 1 having a large light emission amount can be realized.

  Although the element mounting portion 6 in the light emitting device 1 of the present embodiment is made of Cu or Al, the performance of the light emitting element 3 to be mounted, the type, characteristics, and cost of the substrate 4 are not limited to these. The material for the element mounting portion 6 may be selected. For example, the element mounting portion 6 may be formed using a composite material such as Cu—W (tungsten). Thus, when using composite materials, such as Cu-W containing two or more types of metals, the element mounting part 6 which has a desired characteristic can be produced by adjusting the metal to be used and its ratio. it can. The element mounting portion 6 may be formed of an alloy. Further, the element mounting portion 6 may be formed of ceramics, and in this case, it can be fired simultaneously with the substrate 4.

  Further, although the substrate 4 of the light emitting device 1 of the present embodiment is made of ceramics, it may be formed of an organic resin. Since the resin substrate is cheaper than the ceramic substrate, an inexpensive light-emitting element wiring substrate 2 can be obtained. Further, in order to improve rigidity, strength, hygroscopicity, heat resistance and the like, it is desirable to form the substrate 4 using a resin substrate containing ceramic powder and glass cloth.

  Further, the frame portion 7 of the light-emitting device 1 of the present embodiment is formed so as to be inclined with respect to the thickness direction Z although the inner peripheral surface is formed in parallel with the thickness direction Z. For example, the cross section perpendicular to the thickness direction Z of the inner peripheral surface of the frame portion 7 may be formed so as to become wider as the distance from the substrate 4 increases. Thus, by setting the shape of the inner peripheral surface of the frame part 7, the light emission angle of the light emitting device 1 can be arbitrarily adjusted.

  Moreover, although the frame part 7 of the light emitting device 1 of the present embodiment is made of metal, it may be made of ceramics. In this case, when the substrate 4 is fired, the frame portion 7 can be fired at the same time, and the process can be simplified, so that the inexpensive light emitting element wiring substrate 2 can be easily manufactured. In addition, since ceramics are excellent in heat resistance and moisture resistance, the use of the ceramic frame portion 7 makes it possible to use the light emitting device 1 for a long period of time and use the light emitting device 1 under adverse conditions. Thus, the light emitting element wiring board 2 is provided.

  Further, in addition to the light emitting device 1 of the present embodiment, a cooling device such as a heat sink may be provided on the other surface in the thickness direction Z of the element mounting portion 6. By providing the cooling device, the heat dissipation is further improved.

  In addition, a reflective film having a high reflectance with respect to the wavelength of light of the light emitting element 3 to be mounted may be formed on the substrate 4 of the light emitting device 1 according to the present invention. For example, when a reflective film is formed on the substrate 4 using an electroless plating method, light incident on the substrate is reflected in the light extraction direction, so that the light from the light emitting element 3 can be used effectively, and the light emitting device The light extraction efficiency can be improved.

  In the light emitting device 1 of the present embodiment, the wiring 5 and the light emitting element 3 are electrically connected by the bonding wire 27, but may be electrically connected by flip chip connection.

  Further, in the light emitting device 1 of the present embodiment, the light emitting element 3 is covered with the covering portion 31, but the light emitting element 3 is sealed using, for example, a light-transmitting lid without forming the covering portion 31. May be. The lid is formed so as to cover the lighting device 1 from one side Z1 in the thickness direction Z, for example. Further, a lid may be further formed in addition to the covering portion 31. As the lid, it is desirable to use a translucent material such as glass. Further, a phosphor for converting the wavelength of light emitted from the light emitting element 3 may be added to the covering portion 31.

  In the light emitting device 1 of the present embodiment, the configuration in which the light emitting element 3 is connected to the first and second backside pad electrodes 23 and 23 via the first and second through electrodes 9 and 11 has been described. The lighting device may be configured to supply power to the light emitting element 3 from the one surface 13 side in the thickness direction Z of the substrate 4 without providing the first and second through electrodes 9 and 11. Moreover, the board | substrate 4 may be comprised by the multilayer board | substrate.

  In the light emitting device 1 of the present embodiment, the frame portion 7 is provided, but a light emitting device that does not include the frame portion 7 may be configured.

  In the light emitting device 1 according to the present embodiment, the area of the mounting surface 15 and the area of the mounting surface 20 facing the protrusion 14 of the light emitting element 3 are selected to be equal. It may be smaller than the area of the mounting surface 20 of the element 3. Even in this case, as described above, the light from the light emitting element 3 enters the outer peripheral surface 17 of the protrusion 14, so that the light extraction efficiency of the light emitting device 1 is improved.

  Further, although the light emitting element 3 and the substrate 4 of the light emitting device 1 of the present embodiment have a square cross section in the thickness direction Z, they are not limited to a square but may be a rectangle, a circle, an ellipse, or the like. .

  FIG. 3 is a cross-sectional view showing an element mounting portion 41 of a light emitting device according to another embodiment of the present invention. Since the light emitting device of the present embodiment has the same configuration as the light emitting device 1 of the above-described embodiment except for the protrusion 42, the description of the configuration other than the protrusion 42 will be omitted, and only the protrusion 42 will be described. explain.

  The shape of the protrusion 42 is similar to the shape of the protrusion 14 of the above-described embodiment. The outer peripheral surface 43 of the projecting portion 42 is not flat in the present embodiment, and is formed to be curved inside the element mounting portion 41 as compared to the planar outer peripheral surface 17 of the projecting portion 14 of the above-described embodiment. The Even when the protrusions 14 are formed in this way, the light extraction efficiency of the light emitting device 1 is improved as described above.

  FIG. 4 is a cross-sectional view showing an element mounting portion 45 of a light emitting device according to still another embodiment of the present invention. Since the light emitting device of the present embodiment has the same configuration as the light emitting device 1 of the above-described embodiment except for the protrusion 46, the description of the configuration other than the protrusion 46 will be omitted, and only the protrusion 46 will be described. explain.

  The shape of the protrusion 46 is similar to the shape of the protrusion 14 of the above-described embodiment. The outer peripheral surface 47 of the protrusion 46 is not flat in the present embodiment, but is curved outward of the element mounting portion 45 as compared to the planar outer peripheral surface 17 of the protrusion 14 of the above-described embodiment. Is done. Even when the protrusions 14 are formed in this way, the light extraction efficiency of the light emitting device 1 is improved as described above.

  FIG. 5 is a cross-sectional view showing an element mounting portion 49 of a light emitting device according to yet another embodiment of the present invention. The light emitting device according to the present embodiment has the same configuration as that of the light emitting device 1 according to the above-described embodiment except for the protrusion 50. Therefore, the description of the configuration other than the protrusion 50 will be omitted, and only the protrusion 50 will be described. explain.

  The shape of the protrusion 50 is similar to the shape of the protrusion 14 of the above-described embodiment. A recess 51 that retreats inside the protrusion 50 is formed at the peripheral edge of the other end in the thickness direction Z of the protrusion 50. Since the projection 50 has the recess 51, the covering portion 31 fits into the recess 51. This improves the adhesion between the covering portion 31 and the light emitting element wiring substrate.

  FIG. 6 is a cut end view showing a frame portion 53 of a light emitting device according to still another embodiment of the present invention. Since the light-emitting device of the present embodiment has the same configuration as that of the light-emitting device 1 of the above-described embodiment except for the frame portion 53, the description of the configuration other than the frame portion 53 will be omitted, and only the frame portion 53 will be described. explain.

  At one end portion in the thickness direction Z of the frame portion 53, a flange portion 54 extending inward of the frame portion is formed. Since the frame part 53 has the flange part 54, the coating | coated part 31 fits in the wiring board for light emitting elements. This improves the adhesion between the covering portion 31 and the light emitting element wiring substrate. Since the flange 53 blocks light from the light emitting element 3, the flange 53 is formed to have such a size that the light quantity of the light emitting device does not decrease and the adhesion to the cover 31 increases.

(Example)
The light emitting device 1 shown in FIGS. 1 and 2 was manufactured, and the light amount of the light emitting device 1 was measured.

First, in order to prepare the substrate 4, 90% by mass of Al ₂ O ₃ powder as a raw material powder, 5% by mass of MgO powder, and 5% by mass of SiO ₂ powder are mixed, and acrylic molding as a binder. An organic resin was used and mixed using toluene as a solvent to prepare a slurry. The Al ₂ O ₃ powder has a purity of 99% by mass or more and an average particle size of 1.0 μm, and the MgO powder has a purity of 99% by mass or more and an average particle size of 1.3 μm. As the SiO ₂ powder, one having a purity of 99% by mass or more and an average particle diameter of 1.0 μm was used. Thereafter, a ceramic green sheet was produced by using a doctor blade method.

Next, a conductive paste was prepared as a material for the wiring 5. The conductive paste was prepared by mixing 95% by mass of W powder and 5% by mass of Al ₂ O ₃ powder, using an acrylic resin as a binder, and using acetone as a solvent. W powder having an average particle diameter of 2 μm was used, and Al ₂ O ₃ powder having an average particle diameter of 1.0 μm was used. Next, the produced ceramic green sheet was punched to form the first through hole 8, the second through hole 10, and the third through hole 12. The diameters of the second through hole 10 and the third through hole 12 are set to 100 μm, and the prepared conductive paste is filled into the second through hole 10 and the third through hole 12 by a screen printing method. A conductive paste was printed and applied in a wiring pattern on the portion where the electrode 21, the second front surface pad electrode 22, the first back surface pad electrode 23, and the second back surface pad electrode 24 were formed.

  The green sheet thus produced has a dimension D2 in the first width direction X, a dimension W3 in the second width direction Y, and a dimension H6 in the thickness direction Z after firing, D2 = 10 mm, W3 = 10 mm, and H6 = They were combined, aligned, laminated and pressure-bonded and fired so that the thickness became 0.6 mm. After firing, Ni plating and Au plating were sequentially performed on the surfaces of the first surface pad electrode 21, the second surface pad electrode 22, the first back surface pad electrode 23, and the second back surface pad electrode 24.

The frame portion 7 was formed using a metal made of Al having a thermal expansion coefficient of 23 × 10 ⁻⁶ / ° C. and a thermal conductivity of 238 W / m · K. Before joining the frame portion 7 to the substrate 4, the metal layer is applied to the peripheral portion where the frame portion 7 on the one surface 13 of the thickness direction Z of the substrate 4 is mounted using the conductive paste for the wiring 5 described above. Formed. Next, the frame portion 7 was joined to the substrate 4 using solder.

  The element mounting portion 6 made of Cu was molded so that the distance between the surface of the element mounting portion main body 19 and the inner peripheral surface of the substrate 4 facing the first through hole 8 was 100 μm to 300 μm. Further, a layer made of Ni, a layer made of Au, and a layer made of Ag were plated in this order on the surface of the element mounting portion 6 to form a reflective film 18. A eutectic Ag—Cu brazing paste is applied to the inner peripheral surface of the substrate 4 facing the first through hole 8, the element mounting portion 6 is inserted into the first through hole 8, and nitrogen and hydrogen are mixed at 890 ° C. Heat treatment was performed for 30 minutes in an atmosphere to form the first bonding portion 16 and bond the element mounting portion 6 to the substrate 4.

Next, Au—Sn brazing material is applied to the mounting surface 15, the LED chip as the light emitting element 3 is mounted on the mounting surface 15, and the second bonding portion 26 is formed by heating in a nitrogen atmosphere at 400 ° C. The light emitting element 3 was joined to the element mounting portion 6. In this example, an LED chip with an output of 1.5 W was used for the light emitting element 3. Next, the light emitting element 3 and the wiring 5 were electrically connected by the bonding wire 27. Next, an epoxy resin having a thermal expansion coefficient of 40 × 10 ⁻⁶ / ° C. was filled in the light-emitting element wiring board 2 and cured to prepare the covering portion 31.

  The dimension H1 in the thickness direction Z of the protrusion 14 of the manufactured light emitting device 1 is 0.2 mm, the inclination angle θ of the outer peripheral surface 17 from the thickness direction Z is 60 °, and the first and second surface pads The dimension H4 in the thickness direction Z of the electrodes 21 and 22 is 0.01 mm, the dimension H3 in the thickness direction Z of the second joint portion 26 is 0.005 mm, and the dimension H2 in the thickness direction Z of the light emitting element 3 is 0.1 mm, the dimension D2 in the first width direction X of the light emitting device 1 is 4 mm, the dimension D1 in the first width direction X of the light emitting element 3 is 0.6 mm, and The dimension W2 in the two width directions Y is 0.6 mm, the dimension W1 between the faces of the frame portion 7 facing each other is 3 mm, and the dimension H5 in the thickness direction Z of the frame portion 7 is 0. .5 mm.

  A 0.4 A current was passed through the manufactured light emitting device 1 and a total radiant flux measurement was performed 1 hour after the start of the current supply. At this time, the light intensity from the light emitting device 1 was 210 mW.

(Comparative example)
FIG. 7 is a cross-sectional view of a light emitting device 56 manufactured as a comparative example. The light emitting device 56 manufactured as a comparative example has a different shape from the element mounting portion 6 of the light emitting device 1 manufactured in the example, and the shape other than the element mounting portion 6 is the same as the light emitting device 1 manufactured in the example. In FIG. 7, portions of the light emitting device 56 manufactured as a comparative example corresponding to the light emitting device 1 manufactured in the example are denoted by the same reference numerals. The element mounting portion 57 in the light emitting device 58 of the comparative example is formed to extend in the thickness direction Z in a quadrangular prism shape. The dimensions of the element mounting portion 57 in the first width direction X and the second width direction Y are equal to the dimensions of the light emitting element 3 in the first width direction X and the second width direction Y, respectively. A current of 0.4 A was applied to the light emitting device 1 manufactured as a comparative example, and a total radiant flux measurement was performed 1 hour after the start of the current supply. At this time, the light intensity from the light emitting device 1 was 200 mW.

It is sectional drawing which shows the light-emitting device 1 of one Embodiment of this invention. 2 is a plan view of the light emitting device 1. FIG. It is sectional drawing which shows the element mounting part 41 of the light-emitting device of other embodiment of this invention. It is sectional drawing which shows the element mounting part 45 of the light-emitting device of further another embodiment of this invention. It is sectional drawing which shows the element mounting part 49 of the light-emitting device of further another embodiment of this invention. It is a cut end view which shows the frame part 53 of the light-emitting device of further another embodiment of this invention. It is sectional drawing of the light-emitting device 56 produced as a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 2 Light-emitting-element wiring board 3 Light-emitting element 4 Board | substrate 5 Wiring 6,41,45,49,57 Element mounting part 7,53 Frame part 14,42,46,50 Projection part 15 Mounting surface 18 Reflective film 19 Element Mounting body 20 Mounting surface 27 Bonding wire 31 Covering section

Claims (9)

A substrate having electrical insulation and on which wiring is formed;
An element mounting portion on which a mounting surface for mounting a light emitting element is formed at a tip portion that is inclined farthest from the one surface as the outer peripheral surface protrudes from one surface in the thickness direction of the substrate; A wiring board for a light-emitting element, comprising:   The light emitting element wiring board according to claim 1, wherein an area of the mounting surface is selected to be equal to an area of the mounting surface of the light emitting element facing the element mounting portion.   The light emitting element wiring board according to claim 1, wherein the element mounting portion is made of metal.   The said element mounting part penetrates the said board | substrate in the said thickness direction, and is provided in the said board | substrate, The wiring board for light emitting elements as described in any one of Claims 1-3 characterized by the above-mentioned.   The light emitting element wiring board according to claim 1, wherein the element mounting portion is made of copper or aluminum.   6. The method according to claim 1, further comprising a reflective film formed on the outer peripheral surface of the element mounting portion between the mounting surface and the one surface and made of silver or aluminum. The wiring board for light emitting elements as described in 2.   The light emitting device mounted on the mounting surface and a frame portion that surrounds the device mounting portion are further included on one surface of the substrate. Wiring board for light emitting element. A wiring board for a light emitting element according to any one of claims 1 to 7,
A light emitting device mounted on the mounting surface;
A light emitting device comprising: the wiring formed on the substrate; and an element connecting portion for connecting the light emitting elements. The light emitting device according to claim 8, further comprising a covering portion that has a light transmitting property and covers the light emitting element.

Images