JP2019117818A - Mounting substrate, light emitting device, and manufacturing method of light emitting device - Google Patents

Abstract

To provide a mounting substrate, a light emitting device, and a manufacturing method of a light emitting device which are excellent in light extraction efficiency.SOLUTION: A mounting substrate 11 includes a metal plate 1 having a mounting region E1 including a bottom surface 2 and a plurality of convex light emitting element mounting portions 3 extending from the bottom surface 2 and mounting a light emitting element 30, a reflective material 10 covering at least the bottom surface 2 and the entire side surface 4 of the light emitting element mounting portion 3 in the mounting region E1, and a circuit board 20 laminated on the metal plate 1 so that the mounting region E1 of the metal plate 1 is exposed in an opening 25 formed so as to surround the mounting region E1, and the reflectance of the reflective material 10 is higher than the reflectance of the metal plate 1.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a mounting substrate, a light emitting device, and a method of manufacturing the light emitting device.

  In recent years, light emitting elements with high brightness and high output have been developed, and for example, many COB (chip on board) type LED devices (hereinafter referred to as light emitting devices) have been proposed in which LED chips are mounted directly on a heat dissipation substrate. In this light emitting device, for example, a structure is disclosed in which the light extraction efficiency is enhanced by mounting an LED chip on a heat dissipation substrate with a submount structure (see, for example, Patent Document 1).

  As another example, in the light emitting device, the LED element is mounted on the LED element mounting portion of the convexly formed metal plate, and the inside of the groove formed around the LED element mounting portion is filled with high reflective ink A configuration is disclosed (see, for example, Patent Document 2).

JP, 2016-111179, A JP, 2016-207757, A

However, in the light emitting device of Patent Document 1, the heat from the light emitting element is conducted to the aluminum plate through the submount material, and thus the heat dissipation characteristics may be impaired. In addition, since it is necessary to mount the same number of submounts as the number of light emitting elements, the number of steps involved in mounting has increased.
Furthermore, in the light emitting device of Patent Document 2, since the groove is formed around the LED element mounting portion formed in a convex shape to be filled with the highly reflective ink, the highly reflective ink filled in the groove is the LED element mounted It easily adheres to parts and tends to cause mounting defects of LED elements. Further, since the relationship between the size of the lower surface of the LED element and the upper surface of the LED element mounting portion and the relationship between the distance between the LED element and the highly reflective ink are not specified, further light extraction efficiency is desired. .

  Therefore, an embodiment according to the present disclosure is to provide a mounting substrate, a light emitting device, and a method of manufacturing the light emitting device, which are excellent in light extraction efficiency.

The mounting substrate according to the present embodiment includes at least a metal plate having a mounting area including a bottom surface and a plurality of convex light emitting element mounting portions extending from the bottom surface and mounting the light emitting element; A reflective material that covers the bottom surface and the entire side surface of the convex light emitting element mounting portion, and the metal plate so that the mounting area of the metal plate is exposed in an opening formed to surround the mounting area And a circuit board to be laminated, wherein the reflectance of the reflective material is higher than the reflectance of the metal plate.
The light emitting device according to the present embodiment includes the mounting substrate and a light emitting element mounted on a light emitting element mounting portion of the mounting substrate.

  Furthermore, in the method of manufacturing a light emitting device according to the present embodiment, a metal plate having a mounting area including a bottom surface and a plurality of convex light emitting element mounting portions mounting the light emitting element extending from the bottom surface; Preparing a circuit board having an opening formed to surround the light emitting element mounting portion, laminating the circuit board on the metal plate to expose a mounting region in which the light emitting element mounting portion is formed, and the light emitting element A step of providing a reflective material on the bottom surface of the mounting area and the entire side surface of the light emitting element mounting portion such that the upper surface of the reflecting surface is located below the top surface of the mounting portion; Mounting the light emitting element, and electrically connecting the light emitting element and the circuit board with a wire, and the area of the top surface of the light emitting element mounting portion is the area of the bottom of the light emitting element Less than Ku, the reflectivity of the reflective material is higher than the reflectance of the metal plate.

  The mounting substrate and the light emitting device according to the present embodiment can improve the light extraction efficiency. Moreover, the manufacturing method of the light emitting device according to the present embodiment can provide the light emitting device which improves the light extraction efficiency.

It is a perspective view showing typically the mounting board concerning an embodiment. It is a perspective view which shows the light-emitting device concerning embodiment typically. It is a top view which shows typically the mounted substrate and light-emitting device which concern on embodiment. It is sectional drawing in the IV-IV line of FIG. It is an enlarged plan view which expands the V area | region of FIG. 3, and is shown typically. FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 5; FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. 5; It is a flowchart which shows the manufacturing method of the light-emitting device which concerns on embodiment. It is a top view which omits a part of circuit board aggregate used at a preparation process in a manufacturing method of a light emitting device concerning an embodiment, and is shown typically. It is a top view which omits and shows a part of metal plate aggregate used at a preparatory process in a manufacturing method of a light emitting device concerning an embodiment. It is sectional drawing which shows the part corresponding to one metal plate among metal plate assemblies in the manufacturing method of the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically the state which etched about the part of one metal plate among metal plate assemblies in the manufacturing method of the light-emitting device which concerns on embodiment, and formed the light emitting element mounting part. It is sectional drawing which shows typically the state which laminated | stacked the part corresponding to one metal plate and a circuit board among a metal plate aggregate and a circuit board aggregate in the manufacturing method of the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically the state which formed the reflective material in the mounting area | region of one metal plate among the mounting board assemblies in the manufacturing method of the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically the state which removed the reflective material of the upper surface of the light emitting element mounting part formed in the mounting area | region of one metal plate among mounting board assemblies in the manufacturing method of the light emitting device which concerns on embodiment. It is sectional drawing which shows typically the state which mounted the light emitting element in the light emitting element mounting part of one mounting area | region of mounting substrate assemblies in the manufacturing method of the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically the state which connected the wire to one metal plate light emitting element of the mounting substrate assemblies in the manufacturing method of the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically the state which formed the sealing member in one mounting area | region of mounting substrate assemblies in the manufacturing method of the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically one part about the modification of a metal plate in the light-emitting device which concerns on embodiment. It is sectional drawing which shows typically the modification of the mounted substrate which concerns on embodiment, and a light-emitting device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. However, the embodiments described below are for embodying the technical concept of the present invention, and the present invention is not limited to the following ones unless there is a specific description. Further, the sizes and positional relationships of members shown in the drawings may be exaggerated in order to clarify the description. Furthermore, in the drawings, the XYZ directions are illustrated and described, but the directions described in the drawings are arbitrary.

First Embodiment
FIG. 1 is a perspective view schematically showing a mounting substrate according to the embodiment, FIG. 2 is a perspective view schematically showing a light emitting device according to the embodiment, and FIG. 3 shows the mounting substrate and the light emitting device according to the embodiment. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is an enlarged plan view schematically showing an enlarged V region in FIG. 3, FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG.

  The light emitting device 100 includes at least a metal plate 1 having a mounting area E1 including a bottom surface 2 and a plurality of convex light emitting element mounting portions 3 extending from the bottom surface 2 for mounting the light emitting element 30; And the metal plate 1 so that the mounting area E1 of the metal plate 1 is exposed to the reflecting material 10 covering the bottom 2 and the entire side surface 4 of the light emitting element mounting portion 3 and the opening 25 formed to surround the mounting area E1. And a circuit board 20 to be stacked. In the light emitting device 100, the plurality of light emitting element mounting portions 3 are formed in the mounting area E1 so that the plurality of light emitting elements 30 can be provided.

  The metal plate 1 is provided with a bottom surface 2 and a plurality of light emitting element mounting portions 3 formed at a position higher than the bottom surface 2 in a mounting area E1 which is a predetermined area range. The metal plate 1 is formed such that a circular mounting area E1 is set at the center of a rectangular plate as an example, and a circuit board 20 described later is installed on the peripheral portion 6 which is the periphery of the mounting area E1. The metal plate 1 is preferably made of, for example, a metal that can be easily processed, such as copper or a copper alloy, an aluminum plate, a steel plate (for example, a SUS plate). Further, the metal plate 1 is formed such that its peripheral portion 6 is higher than the upper surface 5 of the light emitting element mounting portion 3.

  The light emitting element mounting portion 3 is a portion where the light emitting element 30 is installed at a position higher than the bottom surface 2. A plurality of the light emitting element mounting portions 3 are formed in the mounting area E1 at predetermined intervals. The light emitting element mounting portion 3 is integrally formed from the bottom surface 2. The light emitting element mounting portion 3 has a side surface 4 extending upward from the bottom surface 2 and an upper surface 5 formed at an upper end portion of the side surface 4. That is, the top surface 5 of the light emitting element mounting portion 3 is formed at a high position extending from the bottom surface 2. The light emitting element mounting portion 3 is integrally formed with the bottom surface 2 by etching or bending a flat plate in the thickness direction in a manufacturing method described later. The light emitting element mounting portion 3 extends from the bottom surface 2 to form the top surface 5 at a high position, and the bottom surface 2 and the top surface 5 are formed to have a step via the side surface 4. Note that “extending from the bottom surface 2” indicates that the bottom surface 2 and the top surface 5 are formed with different heights, and includes forming by pressing or etching. Therefore, extending from the bottom surface 2 is not limited to extending and forming the plate. The light emitting element mounting portion 3 is integrally formed with the bottom surface 2 to improve the heat dissipation.

  Here, the light emitting element mounting portion 3 is illustrated as an example formed in a truncated pyramid shape, but the shape may be, for example, a column, a truncated cone, a rectangular parallelepiped, a cube or the like. Moreover, the light emitting element mounting part 3 can improve reflectivity, when the side surface 4 is a shape which has inclination. When the light emitting element mounting portion 3 has a shape such as a truncated pyramid in which the side surface 4 is inclined, the inclination angle θ1 formed by the bottom surface 2 and the side surface 4 is preferably more than 90 degrees and 120 degrees or less. When the inclination angle θ1 of the side surface 4 becomes larger than 120 degrees, it is necessary to increase the distance in the mounting area of the light emitting element mounting portion 3, which may be unsuitable for the configuration in which many light emitting elements 30 need to be mounted. . If the inclination angle θ1 of the side surface 4 is less than 90 degrees (particularly 80 degrees or less), the area of the region surrounded by the lower end of the side surface 4 may be smaller than the area of the upper surface 5 and it may be difficult to form. Further, by setting the inclination angle θ1 to be more than 90 degrees and not more than 120 degrees, the reflective material 10 tends to crawl up the side surface 4 of the light emitting element mounting portion 3, and the side surface 4 of the light emitting element mounting portion 3 with a small amount of reflective material 10 Can cover the entire surface of the Further, the distance between adjacent light emitting elements 30 can be narrowed, and the light emitting elements 30 can be mounted with high density. Further, by enhancing the thermal conductivity from the light emitting element 30 to the metal plate 1, the heat dissipation can be enhanced. Furthermore, peeling can be reduced by increasing the contact area between the side surface 4 and the bottom surface 2 of the light emitting element mounting portion 3 and the reflective material 10.

Further, it is preferable that the bottom surface 2 and the upper surface 5 of the light emitting element mounting portion 3 be parallel to each other. When the bottom surface 2 and the top surface 5 of the light emitting element mounting portion 3 are parallel to each other, the reflecting material 10 can be easily formed at an even height with respect to the side surface 4 of the light emitting element mounting portion 3 when the reflecting material 10 is provided. .
In addition, the light emitting element mounting units 3 are arranged at regular intervals when the vertical direction with respect to the plane of the drawing is a row (vertical) direction. Further, the light emitting element mounting portion 3 is disposed with a gap in between in the row direction (horizontal direction) when the direction to the left and right with respect to the paper surface is the row direction. When the above-mentioned arrangement is viewed differently, the light emitting element mounting portion 3 is aligned so that six things are evenly arranged in the periphery with respect to the one located at the center, as shown in FIG. 5 . Alternatively, the light emitting element mounting units 3 are arranged to be aligned obliquely downward to the right and obliquely downward to the left at fixed intervals. The arrangement of the light emitting element mounting units 3 is set according to the number and intervals of installation.

Furthermore, in the light emitting element mounting portion 3, the area of the upper surface 5 is preferably 80% or less, more preferably 70% or less of the area of the bottom surface of the light emitting element 30. Since the area of the upper surface 5 of the light emitting element mounting portion 3 is smaller than the area of the bottom of the light emitting element 30, even if part of the light from the light emitting element 30 is emitted toward the reflective material 10 side, It can be reflected and sent upward. In addition, when the area of the upper surface 5 is significantly smaller than the area of the bottom surface of the light emitting element 30, high accuracy is required for mounting the light emitting element 30. Therefore, the area of the upper surface 5 is 40% or more, preferably 50% or more, with respect to the area of the bottom surface of the light emitting element 30.
The center of the light emitting element 30 is preferably equivalent to the center of the top surface 5 of the light emitting element mounting portion 3, but the center of the light emitting element 40 is offset from the center of the top surface 5 of the light emitting element mounting portion 3. May be However, it is preferable that the top surface 5 of the light emitting element mounting portion 3 be covered with the light emitting element 30 and not be visually recognized in a plan view.
Instead of mounting the light emitting element, a protective element, a semiconductor element or the like may be mounted on the convex portion (upper surface 5) formed in the metal plate 1, or nothing may be mounted.

  The light emitting element mounting portion 3 is formed such that the height from the bottom surface 2 to the top surface 5 is 0.01 mm or more. And it is preferable that the height to the upper surface 5 of the light emitting element mounting part 3 is 0.03 mm or more from bottom face 2, and it is more preferable that it is 0.05 mm or more. Further, the top surface 5 of the light emitting element mounting portion 3 may be formed at a position higher by 0.08 mm or more than the bottom surface 2, and may be 0.2 mm or more. In the case where the height of the upper surface 5 of the light emitting element mounting portion 3 is formed at a position higher than the bottom surface 2 by a predetermined range, a plurality of them can not be formed by one etching or one press. It can be formed by performing etching, pressing, or the like. The thickness of the metal plate 1 is not particularly limited, but is preferably 0.5 mm to 5 mm, and more preferably 1 mm to 3 mm. Here, the thickness of the metal plate 1 means from the back surface of the metal plate 1 to the upper surface 5 of the light emitting element mounting portion 3 in a convex shape.

  Further, the size of the mounting area E1 is set in advance by the number and intervals of the light emitting element mounting portions 3 to be formed. Here, the mounting area E1 is formed to be circular in plan view, but its shape is not particularly limited, such as rectangular or elliptical. The peripheral portion 6 of the mounting area E1 is formed flat at a height equal to or greater than or equal to the height of the upper surface 5 of the light emitting element mounting portion 3 in order to form a wiring 22 described later.

  The reflective material 10 is formed so as to cover the whole of the bottom surface 2 and the side surface 4 of the light emitting element mounting portion 3 in the mounting area E1. The reflective material 10 is provided to reflect and transmit the light from the light emitting element 30 upward. As the reflective material 10, a material having a reflectance higher than that of the metal plate 1 is used. The reflectance of the reflective material 10 is preferably 80% or more in visible light reflectance. As a base material which can reflect light from the light emitting element 30 and which is a material higher than the visible light reflectance of the metal plate 1, for example, silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, acrylic It can form using resin, a hybrid resin, etc. containing 1 or more types of resin, and a reflective substance. Examples of the reflective material to be a material having a higher reflectance than the visible light of the metal plate 1 include titanium oxide, silica, silicon oxide, zirconium oxide, potassium titanate, alumina, aluminum nitride, boron nitride, mullite and the like. In the reflective material 10, the reflective material may be dispersed in the above-described base material or may be formed by dispersing the reflective material on the base material. And as a reflective substance, it is more preferable that it is an inorganic material.

The content of the reflective substance or the like can be appropriately adjusted according to the characteristics of the light emitting device 100 to be obtained because the amount of reflection and transmission of light of the reflective material 10 can be varied. The reflective material 10 preferably has a reflective material content of, for example, 30 wt% or more.
The reflective material 10 may use a material having heat dissipation in addition to the reflectivity. The thermal conductivity of the reflective material 10 is preferably 0.2 W / m · K or more, and more preferably 1 W / m · K or more. Heat dissipation can be improved by setting the thermal conductivity high. As a material for increasing the thermal conductivity, aluminum nitride and boron nitride can be mentioned.

  The reflective material 10 can be formed by, for example, injection molding, potting molding, resin printing, transfer molding, compression molding, gravure printing, ink jet printing, dipping, dispensing, spray coating, or the like. The reflective material 10 is, as an example, filled in the mounting area E1 in a soft state to the same height as the upper surface 5 of the light emitting element mounting portion 3 and resulting in drying. It can be formed by lowering the height of ten. Alternatively, the reflective material 10 may be dried by covering the entire side surface 4 of the light emitting element mounting portion 3 and the position of the upper surface 5 and removing the reflective material 10 on the upper surface 5. By making the height of the reflective material 10 lower than the upper surface 5 of the light emitting element mounting portion 3 as described above, even if the die bonding resin 40 protrudes from the upper surface 5 of the light emitting element mounting portion 3, die bonding is performed on the side surface of the light emitting element 30. The mounting defect of the light emitting element 30 can be reduced without the resin adhering. In addition, when the reflective material 10 is drawn, a gap is formed between the light emitting element 10 and the reflective material 10, and light emitted from the bottom surface of the light emitting element 10 can be efficiently reflected by the reflective material 10.

The circuit board 20 is for electrically connecting to the light emitting element 30 and for electrically connecting to the outside. Here, the circuit board 20 is laminated on the upper surface of the peripheral portion 6 of the metal plate 1 via an adhesive. The circuit board 20 includes an insulating base 21 whose outer shape is formed in a rectangular shape, a wiring 22 formed on the base 21, and an opening 25 formed so as to surround the mounting area E1.
The base 21 of the circuit board 20 has an insulating property. Examples of the substrate 21 include insulating members such as glass epoxy, resin, and ceramics, and metal members provided with the insulating members. Among them, it is preferable to use an inexpensive insulating material such as BT resin, glass epoxy, epoxy resin, or polyimide as the material of the base 21. However, ceramics having high heat resistance and weather resistance can also be used. The ceramic material may, for example, be alumina, aluminum nitride or mullite.

The wiring 22 is formed on the base material 21 and includes wire connection parts 23 a and 24 a for connecting to the wires 50 from the light emitting element 30 and external connection terminals 23 and 24 for connecting to the outside. The material of the wiring 22 can be formed of, for example, a metal such as copper, aluminum, gold, silver, platinum, titanium, tungsten, palladium, iron, nickel or an alloy containing these. The wiring 22 can be formed by electrolytic plating, electroless plating, vapor deposition, sputtering or the like.
The wire connection portions 23 a and 24 a are formed in a semicircular arc band along the periphery of the opening 25 so as to be separated from the opening 25. The wire connection portions 23a and 24a are continuously formed on the external connection terminals 23 and 24 via connection lines in a state in which the end portions face each other and are separated. The wire connection portions 23a and 24a are formed to have a predetermined width, and are formed so that the wires 50 can be easily connected.
The external connection terminals 23 and 24 are respectively formed in a rectangular shape at two of four corners in plan view. The external connection terminals 23 and 24 may be marked at adjacent positions so that one is an anode or a cathode. The shape of the external connection terminals 23 and 24 is not particularly limited, such as rectangular.

The circuit board 20 and the metal plate 1 are bonded by an adhesive 15.
The adhesive 15 bonds the circuit board 20 to the metal plate 1 by being provided on either or both of the peripheral portion 6 of the metal plate 1 and the lower surface of the circuit board 20. The adhesive 15 may be a known adhesive such as epoxy resin, silicone resin, acrylic resin or fluorine resin, adhesive of thermoplastic or thermosetting resin, organic adhesive, adhesive of low melting point glass, or the like. it can. The adhesive 15 is more preferably an inorganic adhesive. The adhesive 15 is less likely to be deteriorated by heat and light when it is an inorganic adhesive, and is particularly convenient when used near the light emitting element 30 that emits high-intensity light.
Further, it is preferable that the upper surface of the circuit board 20 be covered with the insulating resin 26 except for the portion of the wiring 22. Further, the resin 26 to be coated is more preferably excellent in light reflectivity. For example, the resin 26 to be coated can be used if it is the one described in the reflective material 10 and has insulation. By providing the resin 26 in the portion of the peripheral portion 6 excluding the wiring 22 of the circuit board 20, insulation can be ensured.

  The mounting board 11 is formed by joining the metal plate 1 and the circuit board 20 and forming the reflective material 10. The mounting substrate 11 becomes the light emitting device 100 by being provided with the light emitting element 30 and the wire 50. The mounting substrate 11 is formed with a plurality of light emitting element mounting portions 3 in the mounting area E1 so as to be equally spaced from one another. In the light emitting device 100, the sealing member 60 for protecting the light emitting element 30 and the like is formed in the mounting area E1 of the metal plate 1.

(Light emitting element)
For example, an LED chip can be used as the light emitting element 30. Further, the light emitting element 30 may be provided with a plurality of elements having the same configuration, or may be provided with a plurality of types of configurations. Furthermore, the light emitting element 30 may emit light of different colors. The light emitting elements 30 are mounted one by one on the upper surface 5 of the light emitting element mounting portion 3 in the mounting area E1. Since the light emitting elements 30 are arranged at substantially equal intervals in the mounting area E1, it is possible to suppress unevenness in luminance of the light emitted from the light emitting device 100.

  The light emitting element 30 is installed using the insulating die bonding resin 40 such as silicone resin, with the surface opposite to the surface on which the element electrode is provided facing the upper surface 5 of the light emitting element mounting portion 3. The light emitting elements 30 mounted on the light emitting element mounting portion 3 are electrically connected in series or in parallel using the wires 50. The emission intensity of the light emitting element 30 can be changed by controlling the current or voltage of the wiring 22. The light emission intensity when using two types of light emitting elements 30 can be changed by controlling the current or voltage between the wirings. The number of light emitting elements 30 may be one or more. The arrangement intervals of the light emitting elements 30 are preferably approximately equal. Further, the electrical connection method of the light emitting element 30 is not particularly limited, and a plurality of the light emitting elements 30 may be divided into one or more sets and may be connected in series, respectively. It may be done.

  The light emitting element 30 is formed by forming a semiconductor such as GaAlN, ZnS, ZnSe, SiC, GaP, GaAlAs, AlN, InN, AlInGaP, InGaN, GaN, AlInGaN or the like on a substrate such as sapphire as a light emitting layer. Among these, a nitride-based compound semiconductor device having an emission peak wavelength in the short wavelength range (360 nm to 550 nm) of visible light from the ultraviolet range can be used. Note that a light emitting element having a light emission peak wavelength in a long wavelength range (551 nm to 780 nm) of visible light can also be used.

  As the die-bonding resin 40 for placing the light emitting element 30 on the upper surface 5 of the light emitting element mounting portion 3, a resin material which is less likely to cause discoloration or deterioration by light or heat emitted from the light emitting element 30 is preferable. Furthermore, the die-bonding resin 40 preferably has good transparency and is preferably equal to or less than the refractive index of the sealing member 60 described later. By making the refractive index of the die bonding resin 40 equal to or less than the refractive index of the sealing member 60, light emitted from the light emitting element 30 through the die bonding resin 40 is at the interface between the die bonding resin 40 and the sealing member 60. It can be efficiently taken out without being totally reflected. As such a resin material, a silicone-based die-bonding resin having a siloxane skeleton is preferable. Examples of silicone-based die-bonding resins include silicone resins, silicone hybrid resins, and silicone-modified resins.

The wire 50 connects the external connection portion of the n-side electrode of the light emitting element 30 to the external connection portion of the p-side electrode, or electrically connects the external connection portion of the light emitting element 30 to the wire connection portions 23a and 24a. It is a thing. The wire 50 is also used to electrically connect to the electrode of the protective element when the protective element is provided.
As the wire 50, Au, Cu, Al, Ag, or an alloy containing any of these metals as a main component can be suitably used. The protective element is for protecting the light emitting element 30 from electrostatic discharge. It is preferable to provide. As a protective element, a zener diode can be used in parallel with the light emitting element 30 and connected in reverse polarity. In addition, as a protective element, a varistor, a resistor, a capacitor, or the like can also be used.

Moreover, it is preferable that the sealing member 60 be provided in the mounting area | region E1 in which the reflective material 10 was provided (refer FIG. 4). The sealing member 60 is more preferably provided so as to cover the wire connecting portions 23a and 24a of the peripheral portion 6 and the wires 50 connected to the wire connecting portions 23a and 24a. .
The sealing member 60 is a member that covers the light emitting element 30, the wire 50, and the like. The sealing member 60 may not be provided, but by providing it, the sealed member can be protected from deterioration due to moisture or gas or damage due to mechanical contact. The sealing member 60 preferably has, for example, good transparency to the wavelength of light emitted by the light emitting element 30, and a thermosetting resin or a thermoplastic resin can be used.
Although the material which can be used as the sealing member 60 is not particularly limited, it is preferable to have good translucency. Examples of such a material include resin materials such as silicone resin and epoxy resin, and inorganic materials such as glass.
In addition, the sealing member 60 may contain a fluorescent material for converting the wavelength of the light from the light emitting element 30 or a light reflective material for scattering the light from the light emitting element 30.

The light reflective material preferably has an insulating property, and for example, particles of titanium oxide, aluminum oxide or the like can be used.
Moreover, as a fluorescent substance, what is necessary is to be what absorbs the light from the light emitting element 30, and carries out wavelength conversion to the light of a different wavelength. For example, what is generally used as a fluorescent material, such as aluminum garnet fluorescent substance, may be used.
Alternatively, fluorescent materials may be disposed on individual light emitting elements 30 and covered with sealing members 60 containing different fluorescent materials. The disposition of the fluorescent substance on the light emitting element 30 can be performed by applying particles of the fluorescent substance, or attaching a layer or a sheet containing the fluorescent substance. Thereby, light emitting devices of various colors can be provided.

  In the light emitting device 100 having the above configuration, the reflective material 10 is provided so as to cover the side surface 4 of the light emitting element mounting portion 3, and the reflectance of the reflective material 10 is higher than the reflectance of the metal plate 1. It is formed to be high. Therefore, even when part of the light from the light emitting element 30 travels to the side of the reflective material 10, the light emitting device 100 can efficiently reflect and take out light. In particular, when the side surface of the light emitting element mounting portion 3 is a slope, light can be extracted more efficiently. Further, in the light emitting device 100, light is emitted when the area of the upper surface 5 of the light emitting element mounting portion 3 is 70% or less of the area of the bottom surface of the light emitting element 30, and the side surface 4 of the light emitting element mounting portion 3 is an inclined surface It becomes easy to reflect a part of light from the element from the reflective material 10, and it becomes possible to improve the light extraction efficiency.

Next, a method of manufacturing the light emitting device 100 will be described below with reference to the drawings. FIG. 8 is a flowchart showing a method of manufacturing the light emitting device according to the embodiment.
Here, the method of manufacturing the light emitting device includes a preparation step S11 of preparing the metal plate 1 and the circuit board 20, a lamination step S12 of laminating the metal plate 1 and the circuit board 20, and a mounting area E1 of the metal plate 1. A reflective material forming step S13 for providing the reflective material 10, a light emitting element mounting step S14 for mounting the light emitting element on the light emitting element mounting portion, and a wire connecting step S15 for providing the wire 50 to the light emitting element 30 are mainly performed. In the mounting method of the light emitting device, a sealing member forming step S16 of forming a sealing member in the mounting area E1 after the wire connecting step S15 and a singulation step S17 of singulating the assembly of light emitting devices are performed. 10A to 10H, in the metal plate assembly A1 and the circuit board assembly B1, the state of one metal plate 1 portion and one circuit board 20 portion is schematically omitted by omitting a part thereof. Is shown.

(Preparation process)
The preparation process will be described with reference to FIGS. 9A to 10B. FIG. 9A is a plan view schematically showing a circuit board assembly used in the preparation step in the method of manufacturing the light emitting device according to the embodiment, and FIG. 9B is a method of manufacturing the light emitting device according to the embodiment. It is a top view which abbreviate | omits a part of metal plate aggregate | assembly used by a preparatory process, and is shown typically. 10A is a cross-sectional view showing a portion corresponding to one metal plate of the metal plate assembly in the method for manufacturing a light emitting device according to the embodiment, and FIG. 10B is a method for manufacturing a light emitting device according to the embodiment It is sectional drawing which shows typically the state which etched about the part of one metal plate among metal plate aggregate | assembly, and formed the light emitting element mounting part.
In the preparation step S11, substantially, a metal plate assembly A1 in which a plurality of metal plates 1 are formed and a circuit board assembly B1 in which a plurality of circuit boards 20 are formed are respectively prepared. When preparing the metal plate assembly A1 of the metal plate 1, here, a mask is provided on a metal plate of a fixed thickness, for example, a copper alloy plate, and etching is performed. In the metal plate assembly A1, portions corresponding to the plurality of mounting areas E1 and the peripheral portion 6 are formed by etching. In addition, the circuit board assembly B1 includes a plurality of areas to be one circuit board 20 in which the wirings 22 are formed on the base material 21. When preparing the circuit board assembly B1 of the circuit board 20, the wiring 22 is formed for each area on the base plate C1 where a plurality of areas to be the base 21 can be formed. The base plate C1 is provided with a resin 26 which covers the upper surface of the peripheral portion 6 other than the wiring after the wiring 22 is formed. And the circuit board aggregate B1 is prepared by cutting the position corresponding to the mounting area | region E1 of the metal plate 1, and forming the opening 25 as the base material board C1.

(Lamination process)
The lamination step will be described using FIG. 10C. FIG. 10C is a cross-sectional view schematically showing a state in which a portion corresponding to one of the metal plate and the circuit board in the metal plate assembly and the circuit board assembly is stacked in the method of manufacturing a light emitting device according to the embodiment. .
Next, in the laminating step S12, the metal plate assembly A1 having a plurality of metal plates 1 prepared in the preparation step S11 and the circuit board assembly B1 having a plurality of circuit boards 20 are adhered via the adhesive 15. In addition, after bonding through the adhesive 15 in the laminating step S12, a heating step or an ultraviolet irradiation step may be performed depending on the type of the adhesive 15 to cure the adhesive 15.

(Reflective material formation process)
The reflective material forming step will be described with reference to FIG. 10D. FIG. 10D is a cross-sectional view schematically showing a state in which the reflective material is formed in the mounting area of one metal plate of the metal plate assembly in the method of manufacturing a light emitting device according to the embodiment.
In the reflective material forming step S13, after the metal plate assembly A1 and the circuit board assembly B1 are stacked, the reflective material 10 is provided in the mounting area E1 of each of the metal plates 1. In the reflective material forming step S13, the reflective material 10 is formed to cover the entire bottom surface 2 of the mounting area E1 and the side surface 4 of the light emitting element mounting portion 3 by, for example, spray coating or a printing method. The reflective material 10 is dried to cause shrinkage on the member, and indents a portion between the side surfaces 4 of the adjacent light emitting element mounting portions 3. By forming such a recess, the reflective material 10 easily reflects light to the light extraction surface side.

When the reflective material 10 is provided, it is provided so as to cover the bottom surface 2, the side surface 4 and the top surface 5 of the light emitting element mounting portion 3, and then the reflecting material on the top surface 5 of the light emitting element mounting portion 3 is removed. Good. FIG. 10E is a cross section schematically showing a state in which the reflective material on the upper surface of the light emitting element mounting portion formed in the mounting region of one metal plate of the mounting substrate assembly in the method of manufacturing the light emitting device according to the embodiment is removed. FIG. When the reflective material on the upper surface 5 is removed, polishing or cutting is performed. Then, after the polishing process or the cutting process is performed, it is preferable to perform an operation of removing the grinding waste or the cutting waste by the cleaning operation or the like.
Since the reflective material 10 has a higher reflectance than the visible light of the metal plate 1, the reflective material 10 is provided on the entire surface of the bottom surface 2 and the side surface 4 of the light emitting element mounting portion 3 to enhance the efficiency of reflecting light from the light emitting element 30. be able to. By forming the reflective material 10 in the mounting area E1, a mounting substrate assembly of the mounting substrate 11 is formed. By forming the reflective material 10, a mounting substrate assembly having a large number of mounting substrates 11 is formed.

(Light emitting element mounting process)
The light emitting element mounting process will be described using FIG. 10F. FIG. 10F is a cross-sectional view schematically showing a state in which the light emitting element is mounted on the light emitting element mounting portion in one mounting region of the mounting substrate assembly in the method of manufacturing the light emitting device according to the embodiment.
In the light emitting element mounting step S14, the light emitting element 30 is mounted on the upper surface 5 of the light emitting element mounting portion 3 via the die bonding resin 40. In the light emitting element mounting step S14, the area of the upper surface 5 of the light emitting element mounting portion 3 is formed smaller (for example, 40% or more) than the area of the lower surface of the light emitting element 30. Here, the light emitting element 30 is installed on the upper surface 5 of the light emitting element mounting portion 3 in a state where the center thereof coincides with the center of the upper surface 5 and the peripheral edge of the lower surface of the light emitting element 30 protrudes outward from the upper surface 5.

(Wire connection process)
The wire connection process will be described with reference to FIG. 10G. FIG. 10G is a cross-sectional view schematically showing a state in which a wire is connected to one metal plate light emitting element of the mounting substrate aggregate in the method for manufacturing a light emitting device according to the embodiment.
In the wire connection step S <b> 15, the wire 50 is connected to the light emitting element 30 provided on the upper surface 5 of the light emitting element mounting unit 3. Here, in the wire 50, groups of light emitting elements 30 set in advance are connected in series to the wire connection portions 23a and 24a, and the groups are connected in parallel to each other. In the case where the wires 50 are provided in the light emitting element 30, the parallel connection means that the p electrodes or the n electrodes in the adjacent light emitting elements 30 are electrically connected by the wire 50.

(Sealing member formation process)
The sealing member forming step will be described with reference to FIG. 10H. FIG. 10H is a cross-sectional view schematically showing a state in which the sealing member is formed in one mounting region of the mounting substrate assembly in the method of manufacturing a light emitting device according to the embodiment.
In the sealing member forming step S16, after the frame 27 is formed on the metal plate 1, the sealing member 60 is formed in the mounting region E1 of the metal plate 1, thereby the light emission being disposed in the mounting region E1. This is a step of sealing the element 30, the wire 50 and the like. It is preferable that the frame 27 use a resin containing a light reflective substance. The frame 27 may use the same material as the reflective material 10, and for example, a silicone resin or an epoxy resin in which a light reflective substance such as titanium oxide or silica is dispersed at a high concentration can be used. The frame 27 can be formed by dropping and curing the resin in a ring shape on the circuit board 20. In addition, since the frame 27 does not cover the wire, the frame 27 can be attached to the circuit board 20 with an adhesive after the annular formed body is formed. In the sealing member forming step S16, the sealing member 60 in the molten state is filled in the mounting area E1 by potting, for example. Further, the sealing member 60 can be formed to be able to serve as a lens by forming the center in the mounting area E1 higher than the peripheral edge.

(Dividing process)
A singulation step S17 is performed after the sealing member formation step S16.
The singulation step S17 is a step of forming the individual light emitting devices 100 by performing the cutting operation along the connection lines set in advance in the metal plate aggregate A1 for each of the light emitting devices 100. In the singulation step S17, the light emitting device 100 is singulated by cutting a preset cut portion using a cutting device.

  As described above, by performing the preparation step S11 to the reflection material formation step S13, a mounting board assembly having a plurality of mounting boards 11 is formed. Further, the light emitting device 100 can be manufactured by performing the singulation step S17 including the preparation step S11 to the wire connection step S15.

The mounting substrate 11 or the light emitting device 100 described above is not limited to the above-described configurations, and may have the following configuration, for example. FIG. 11 is a cross-sectional view schematically showing a part of a modification of the metal plate in the light emitting device according to the embodiment.
For example, although the light emitting element mounting portion 3 integrally formed from the bottom surface 2 of the metal plate 1 has been described as an example formed by etching, as shown in FIG. 11, the metal plate 1A is pressed by pressing or the like. The light emitting element mounting portion 3A may be formed to protrude at a high position extending from the bottom surface 2A. The metal plate 1A has the same configuration as the mounting substrate 11 and the light emitting device 100 described above except that the metal plate 1A is formed by processing a thin metal plate.

  In the light emitting element mounting portions 3 and 3A, the top surfaces 5 and 5A may be plated with a material different from that of the metal plates 1 and 1A. As the metal to be plated, for example, it is desirable to use a material having a higher visible light reflectance than the metal plates 1 and 1A. Specifically, a metal material such as copper or copper alloy having high workability is used for the metal plate 1, 1A, and as a metal material to be plated, aluminum or an aluminum alloy having a reflectance higher than that of a copper alloy or the like, silver or silver An alloy or the like may be used. The range of design can be expanded by changing the material of the metal of the metal plates 1 and 1A and the material of the metal to be plated.

The mounting area E1 is described as forming the light emitting element mounting portions 3 at equal intervals, but the light emitting element mounting portions 3 may be appropriately changed in arrangement depending on the use for which the light emitting device 100 is used. . The plan view shape of the mounting area E1 is not limited to a circle, and may be, for example, a rectangle, a shape in which corners of a rectangle are formed into a curve, or an ellipse.
A plurality of types of light emitting elements 30, for example, two types, three types, or four types may be used, and an area to be mounted is determined for each type of each light emitting element 30, and a light emitting element mounting portion It is good also as composition mounted in 3. Further, in order to control a plurality of light emitting elements 30 by type, the wirings 22 may be provided independently for each type.

Further, another embodiment will be described with reference to FIG. FIG. 12 is a cross-sectional view schematically showing a modification of the mounting substrate and the light emitting device according to the embodiment. This modification is substantially the same as the above except that the shape of the frame is different.
In the above-described sealing member forming step, the frame 27a is formed by dropping or injecting a resin containing a light reflective substance so as to cover the wire connecting portions 23a and 24a and a part of the wire 50. Since the wire connection parts 23a and 24a are covered with the frame 27a and the frame 27a can be made to have a predetermined thickness and height, the light extraction efficiency from the light emitting element 30 can be improved.

1, 1A metal plate 2, 2A bottom surface 3, 3A light emitting element mounting portion 4 side surface 5 top surface 6 peripheral portion 10 reflective material 11 mounting substrate 15 adhesive 20 circuit substrate 21 base 22 wiring 23 external connection terminal 23a wire connection portion 25 opening Reference Signs List 26 resin 27, 27a frame 29 recess 30 light emitting element 40 die bonding resin 50 wire 60 sealing member 100 light emitting device A1 metal plate aggregate B1 circuit board aggregate C1 base plate E1 mounting region S11 preparation step S12 lamination step S13 reflection member Forming step S14 Light emitting element mounting step S15 Wire connecting step S16 Sealing member forming step S17 Segmenting step

Claims (15)

A metal plate having a mounting area including a bottom surface, and a plurality of convex light emitting element mounting portions extending from the bottom surface and mounting the light emitting element;
A reflective material that covers at least the bottom surface and the entire side surface of the convex light emitting element mounting portion in the mounting region;
And a circuit board laminated on the metal plate such that the mounting region of the metal plate is exposed in an opening formed so as to surround the mounting region.
The mounting substrate wherein the reflectance of the reflective material is higher than the reflectance of the metal plate.   The mounting substrate according to claim 1, wherein the light emitting element mounting portion is formed in a truncated cone, a truncated pyramid, or a columnar shape, and the top surface and the bottom surface of the light emitting element mounting portion are both formed in parallel planes.   The mounting substrate according to claim 1, wherein the light emitting element mounting portion includes a side surface having a slope formed such that an angle between a bottom surface and a side surface is larger than 90 degrees.   The mounting substrate according to any one of claims 1 to 3, wherein the area of the top surface of the light emitting element mounting portion is 70% or less of the area of the bottom surface of the light emitting element.   The mounting substrate according to any one of claims 1 to 4, wherein the reflective material is a material having a visible light reflectance of 80% or more from a reflective surface.   The mounting substrate according to any one of claims 1 to 5, wherein an inorganic material is dispersed in the resin or on the resin.   The mounting substrate according to any one of claims 1 to 6, wherein the metal plate is plated at least on the top surface of the convex light emitting element mounting portion with a material different from the metal plate.   The upper surface of the light emitting element mounting portion and a reflective surface of the reflective material formed on the bottom surface are formed in parallel planes, and the upper surface of the light emitting element mounting portion is higher by 0.01 mm or more than the reflective surface of the reflective material The mounting substrate according to any one of claims 1 to 7, which is a position.   The mounting substrate according to any one of claims 1 to 8, wherein the mounting region is circular or rectangular in plan view, and a plurality of the light emitting element mounting portions are formed at equal intervals.   A light emitting device comprising: the mounting substrate according to any one of claims 1 to 9; and a light emitting element mounted on a light emitting element mounting portion of the mounting substrate.   The light emitting device according to claim 10, wherein the light emitting elements are connected to each other via a wire and connected to a wire connection portion of the circuit board. A metal plate having a mounting area including a bottom surface and a plurality of convex light emitting element mounting portions for mounting the light emitting element extending from the bottom surface; and a circuit board having an opening formed to surround the mounting area The step of preparing
Laminating the circuit board on the metal plate so as to expose a mounting area in which the light emitting element mounting portion is formed;
Providing a reflective material on the entire bottom surface of the mounting area and the entire side surface of the light emitting element mounting portion such that the upper surface of the reflecting surface is located below the top surface of the light emitting element mounting portion;
Mounting a light emitting element on each of the upper surfaces of the light emitting element mounting portion;
Electrically connecting the light emitting element and the circuit board with a wire;
The area of the top surface of the light emitting element mounting portion is smaller than the area of the bottom surface of the light emitting element,
A method of manufacturing a light emitting device, wherein the reflectance of the reflective material is higher than the reflectance of the metal plate. The area of the top surface of the light emitting element mounting portion is 70% or less of the area of the bottom surface of the light emitting element,
The method for manufacturing a light emitting device according to claim 12, wherein the visible light reflectance from the reflection surface is 80% or more.   In the metal plate prepared in the preparing step, the light emitting element mounting portion is formed in a truncated cone, a truncated pyramid, or a columnar shape, and the bottom surface of the metal plate and the upper surface of the light emitting element mounting portion are formed in parallel planes The manufacturing method of the light-emitting device according to claim 13.   The reflective material is filled so as to cover the bottom surface of the mounting area and the top surface of the light emitting element mounting portion, and is then removed by polishing or grinding the reflective material on the top surface of the light emitting element mounting portion The method for manufacturing a light emitting device according to any one of claims 12 to 14, wherein the method is provided on the entire surface of the light emitting element mounting portion and the bottom surface of the light emitting element mounting portion.

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