JP5870582B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device, and more particularly, to a stable light emitting device having a shape that enables high density arrangement.

With the recent development of LEDs, white LEDs can be used for longer life and smaller than incandescent and halogen lamps. Further downsizing is required.
For this purpose, white LEDs are individually or arranged in a high density / highly integrated module to achieve a desired brightness and provide appropriate heat dissipation. Further, a module in which high-brightness LEDs are arranged with high density / high integration is required to be further downsized.

Conventionally, various types of light-emitting devices that enable high density / high integration in consideration of heat dissipation have been proposed. For example, there is a light emitting device in which an LED chip is mounted on the substrate surface, a convex portion having insulation is ensured on the back surface of the substrate, and terminals connected to the electrodes of the LED are arranged on the back surface of the substrate other than the convex portion. It has been proposed (Patent Document 1). And in this light-emitting device, the via conductor from the substrate surface is provided in a region that is not a convex portion formed on the back surface of the substrate, and the terminals are routed to the back surface.
In such a light-emitting device, the convex portion on the back surface of the substrate of the light-emitting device is fixed on the surface of the mounting substrate, the terminal routed by the via conductor is connected to the electrode pad on the mounting substrate, and the convex portion and the mounting substrate are fixed. To achieve heat dissipation.

JP 2008-523578 A

However, in order to stably fix the conventional light emitting device to the mounting substrate with the convex portion on the back surface of the substrate and ensure heat dissipation, the convex portion needs to have a certain width. Cannot be downsized.
In other words, in a situation where further miniaturization is required, when the light emitting device itself, in particular, the substrate and the convex portion formed on the back surface thereof are further miniaturized, the convex portion on the back surface of the substrate is mounted on the mounting substrate. Even if only the substrate is fixed to the mounting substrate, the light emitting device is not stabilized, a mounting defect occurs, and heat dissipation cannot be ensured. In particular, as the light emitting device itself approaches the size of the LED for further miniaturization, such mounting defects become more prominent.

In addition, in order to improve performance, when a protective element or the like coexists in the light emitting device, the substrate area increases depending on the size of these elements in order to secure a mounting area for both. Inevitably, further downsizing of the light emitting device itself cannot be realized.
The present invention has been made in view of the above-mentioned problems, and by realizing further miniaturization, it is possible to realize a high density / highly integrated arrangement, and to stably and surely mount it on a mounting substrate. An object of the present invention is to provide a light emitting device capable of performing the above.

The present application includes the following inventions.
(1) a semiconductor light emitting device;
A protective element having a smaller planar area than the semiconductor light emitting element;
A substrate that supports the semiconductor light emitting element and the protective element ,
A light-emitting device having a through hole penetrating from a surface supporting the semiconductor light-emitting element of the base material to a back surface;
A light emitting device in which the centers of gravity of the semiconductor light emitting element, the protective element, and the through hole are linearly arranged.
(2) The light-emitting device according to any one of the above, wherein the base material includes first and second conductive members on a side surface extending in a short direction.
(3) The light-emitting device according to any one of the above, wherein the first and second conductive members are exposed on the back surface of the base material.
(4) The light emitting device according to any one of the above, wherein the third conductive member is disposed on the back surface of the base material between the first and second conductive members.
(5) The light emitting device according to any one of the above, wherein bottom surfaces of the semiconductor light emitting element and the protection element are electrically connected to the first conductive member, and a top surface of the semiconductor light emitting element is electrically connected to the second conductive member. .

According to the light emitting device of the present invention, it is possible to realize a high density / highly integrated arrangement by further downsizing, and more stable while improving the strength by the thick film of the partial wall surface. Thus, it can be mounted on the mounting board in a reliable and reliable manner.

Left side view (a), plan view (b), bb 'line cross-sectional view (c), right side view (d), longitudinal direction ee' line in the short direction showing the light emitting device of the present invention It is sectional drawing (e), the side view (f) of a longitudinal direction, and a back view (g). However, the cross section of the conductive member is omitted in FIG. It is a reverse view which shows another light-emitting device of this invention. It is a reverse view which shows another light-emitting device of this invention. It is a reverse view which shows another light-emitting device of this invention.

  The light emitting device of the present invention includes at least a semiconductor light emitting element (hereinafter referred to as “light emitting element”), a base material that supports the light emitting element, and a protective element.

[Semiconductor light emitting device]
The light emitting element may be any element as long as it is a so-called light emitting diode. For example, a laminated structure including a light emitting layer is formed on a substrate by various semiconductors such as nitride semiconductors such as InN, AlN, GaN, InGaN, AlGaN, InGaAlN, III-V group compound semiconductors, II-VI group compound semiconductors. What was formed is mentioned.
As a substrate, an insulating substrate such as sapphire or spinel (MgA1 ₂ O ₄ ) whose main surface is any of C-plane, A-plane, and R-plane; silicon carbide (6H, 4H, 3C), silicon, ZnS, Examples include ZnO, GaAs, diamond; oxide substrates such as lithium niobate and neodymium gallate, and nitride semiconductor substrates (GaN, AlN, etc.).

Examples of the semiconductor structure include a homostructure such as a MIS junction, a PIN junction, and a PN junction, a hetero bond, and a double hetero bond.
Each semiconductor layer constituting the light emitting element may be doped with a donor impurity such as Si and Ge and / or an acceptor impurity such as Zn and Mg.
The light emitting layer may have a single quantum well structure or a multiple quantum well structure formed in a thin film in which a quantum effect occurs.
The emission wavelength of the light-emitting element can be changed from the ultraviolet region to red by changing the semiconductor material, the mixed crystal ratio, the In content of InGaN in the light-emitting layer, and the type of impurities doped in the light-emitting layer.
Such a light emitting element may have a laminated structure that can correspond to either flip-chip mounting (face-down) or face-up mounting. For example, a pair of electrodes may be disposed on the front surface side of the light emitting element, or a pair of electrodes may be disposed on the front and back surfaces of the light emitting element.

The size, shape, and the like of the light-emitting element are not particularly limited, and can be appropriately adjusted depending on a material to be used, a target emission wavelength, output, characteristics, and the like. For example, a small light-emitting element having a planar shape of about 150 μm × 150 μm to 5 mm × 5 mm and a thickness of about 50 μm to 500 μm can be given.
The light emitting element is supported on a base material (for example, the first or second conductive member) described later. For the support, a joining member is usually used. For example, in the case of a light-emitting element having blue and green light emission and growing a nitride semiconductor on an insulating substrate, epoxy resin, silicone, or the like can be used. In consideration of deterioration from light and heat from the light emitting element, the back surface of the light emitting element is preliminarily plated with Al, without using resin, solder such as Au—Sn eutectic, brazing material such as low melting point metal, etc. Can also be used. Furthermore, in the case of a light emitting element made of GaAs or the like and having electrodes formed on both sides thereof, such as a light emitting element having red light emission, it may be supported by a conductive paste such as silver, gold or palladium.
In the light emitting device of the present invention, it is preferable that only one light emitting element is mounted, but two or more light emitting elements may be mounted.

[Base material]
The base material supports the above-described light-emitting element and the protection element described later. For example, the base material preferably supports the light-emitting element at or near the center (see, for example, the light-emitting element 2 in FIG. 1B). .
The material which comprises a base material is not specifically limited, It is preferable that it is a material which can thermally radiate the heat | fever generated from a light emitting element effectively.
For example, the thermal conductivity is suitably 10 W / (m · K) or more, preferably 20 W / (m · K) or more, and more preferably 100 W / (m · K) or more. More preferably, it is 200 W / (m · K) or more.
Examples of such a material include semiconductor materials such as Si and SiC, ceramic materials such as Al ₂ O ₃ and AlN, resins (for example, inorganic fillers may be included), and metal plates. Of these, AlN, Si, and the like are preferable in view of high thermal conductivity, workability, and the like. In addition, when a material having characteristics such as conductivity or semiconductor is used as a constituent material of the base material, silicon oxide, silicon nitride, etc. in order to ensure insulation on the outer surface of the base material or a part of the inside thereof Insulating materials may be used.

The base material has at least one through hole penetrating from the surface (front surface side) supporting the light emitting element to the back surface opposite to the surface, and the through hole includes a first or second conductive member described later. , Plays the role of passing from the front surface to the back surface (see 15 in FIG. 1A).
The position of the through hole is not particularly limited, but it is suitable that the through hole is disposed in a recessed portion described later on the front surface side and in a recessed portion described later on the back surface side. This is because, when a conductive member or the like is embedded through the through hole, the influence of the protrusion to the back surface side can be avoided, and the back surface of the base material in contact with the mounting substrate can be maintained flat.

  The shape of the substrate is not particularly limited, and can be various shapes. For example, in plan view (the support surface side of the light emitting element, that is, the surface side), a shape that approximates a circle or an ellipse, a polygon such as a quadrangle, a shape that approximates these polygons (a shape with rounded corners, etc.) ) And the like. In particular, a rectangular shape or a shape similar to this is given (see FIG. 1B). As for the size, considering the recent miniaturization of the light emitting device, it is appropriate that the length in the short direction of the substrate has a length of about 200% to 500% of one side of the light emitting element, Preferably, about 280-420% is mentioned. Specifically, about 1.0 mm-8.0 mm x 1.5 mm-about 50 mm and 2.5 mm-3.0 mm x 5.0 mm-about 50 mm are mentioned. When the plan view is rectangular, it is suitable that the length is about vertical: horizontal = 1: 1.2-10, about 1: 1.2-5, and further 1: 1.5- It is preferable to be about 2. For example, the thickness is suitably about 3 to 10 times that of the light-emitting element, and specifically, a small size of about 0.5 mm to 5 mm is mentioned. About 1.5 mm is suitable.

  The three-dimensional shape of the base material is basically (as a projected shape from the top and bottom surfaces and the side surfaces), and the above-described columnar shape in plan view is suitable, and a rectangular parallelepiped shape is preferable. That is, the base material has a shape having two pairs of side surfaces that extend in the longitudinal direction and the lateral direction and face each other. Here, a pair of side surfaces extending in the longitudinal direction and opposed to each other (hereinafter sometimes referred to as “longitudinal side surfaces”) refers to, for example, the side surface 1d and the side surface 1f in FIG. A pair of side surfaces extending in the direction and facing each other (hereinafter sometimes referred to as “short-side surfaces”) refers to, for example, the side surface 1c and the side surface 1e in FIG. A part of the side surface of the substrate may have a taper or a reverse taper portion (for example, refer to the side surface 1c and the side surface 1e in FIG. 1 (d)), and unevenness may be formed. . In particular, it is preferable that the lower side surface is substantially perpendicular to the front and back surfaces of the substrate and has a tapered portion that is inclined inward on the upper side surface. By setting it as such a shape, when forming a base material with a metal mold | die, the taking-out can be made easy. Further, when the light emitting device is mounted on the mounting substrate, the light emitting device can be reliably held from the side surface direction. For example, the height of the vertical portion is suitably about ½ or more of the height H of the base material.

On the back surface of the substrate (the surface opposite to the surface on which the light emitting element is supported), recesses that reach the side surfaces other than the corners of the substrate are formed. In other words, it has the recessed part opened to the side surface which does not contain the corner | angular part of a base material (it reaches the side surfaces other than the corner | angular part of a base material) of the base material.
For example, (a) you may have a recessed part over a pair of side surface of the longitudinal direction of a base material, and (b) only one side surface (for example, side surface of a transversal direction) among all the side surfaces of a base material. May be provided (see the recess 36 in FIG. 3), or (c) only one side surface (for example, the side surface in the longitudinal direction) of all the side surfaces of the substrate. May be provided (see the recess 46 in FIG. 4).

The shape of the concave portion is not particularly limited, and basically includes a shape lacking a part of a sphere or egg shape, a polygonal column such as a cube or a rectangular parallelepiped, or a shape similar to this. Especially, a cube or a rectangular parallelepiped is preferable.
Therefore, as viewed from the back surface of the base material, this recess is preferably (a) the back surface of the base material is arranged only in two directions in the short direction and is open in two directions in the longitudinal direction. (B) The back surface of the base material is disposed so as to be disposed in one of the two sides in the short direction and the longitudinal direction and opened in one of the short direction, or (c) the back surface of the base material is disposed in the longitudinal direction. Are arranged in one of the two directions and the short direction and are opened in one of the longitudinal directions.

The size of the recess is not particularly limited, and can be appropriately adjusted depending on the size of the base material itself, the stability of the back surface of the base material to the mounting substrate, and the like.
Considering the case where the substrate has a through hole, it is sufficient that the substrate has a shorter width or a longer width than the diameter of the through hole. Specifically, it is preferable that the width of the one side of the substrate is about 5 to 80%, the width is about 5 to 50%, and the width is about 5 to 30%. The depth is not particularly limited, but considering the strength of the base material and the like, it is suitable that it is about 50% or less of the thickness of the base material, preferably about 40% or less, 30% About 20% or less is preferable, 5% or more is sufficient, and 8% or more is preferable. In addition, the wall of the base material which comprises this recessed part may have a taper or reverse taper, and there may be some unevenness | corrugations or a level | step difference.

  The concave portion may be located at any position on the back surface of the base material as long as the shape described above is secured and the arrangement of the light emitting element, the protective element, and the through hole described later can be secured. For example, in the case of (a) described above, it may be biased to either the longitudinal direction and / or the lateral direction, or may be disposed at the central portion in the longitudinal direction / lateral direction. . In the case of (b), it may be biased in either the short direction or may be arranged in the central part in the short direction. In the case of (c), it may be biased in any one of the longitudinal directions, or may be arranged at the central portion in the longitudinal direction.

  Two concave portions may be arranged on opposite sides on the back surface. In addition, when two recessed parts are arrange | positioned, the through hole should just be formed in any one recessed part, and the through hole may be formed in both recessed parts.

The base material may have a hollow part in the site | part which supports a light emitting element and a protection element in the surface (refer 13 of FIG.1 (e)). The size of the recess is larger than the light emitting element and the protective element, and may be smaller than the base material. Thereby, when the light emitting element is mounted on the surface of the substrate, the flatness of the light emitting device can be ensured. In addition, light from the light-emitting element can be aligned on the top surface. Specifically, the depth of the recess is suitably about 0.3 to 3.0, and preferably about 0.5 to 2. The planar shape of the recess is not particularly limited, and as shown in FIG. 1 (b), a polygonal shape or a shape with chamfered polygonal corners, an elliptical shape, a circular shape, a track shape (in the short direction) Various shapes such as a curved side) can be mentioned.
In the dent portion, convex portions (see 14 in FIG. 1E) having a height higher than the dent surface may be formed on both sides of the portion where the light emitting element is disposed. Thereby, while ensuring flatness, while being able to reinforce a thin-film-like base material, it can contribute to the orientation of the light from a light emitting element more. Further, when the above-described through hole is formed in the base material, optical shielding can be ensured by arranging a convex portion between the through hole and the light emitting element. It can be avoided that light hits the through hole directly.

However, the light emitting element, the protection element, and the through hole need to be arranged in parallel in the longitudinal direction. With such an arrangement, the dimension of the light emitting element in one direction, in particular, the lateral direction can be as close as possible to that of the light emitting element, and the light emitting element can be further miniaturized. With such an arrangement, the light emitting device has the same plane area, and in the same occupied area when arranged with high density / high integration compared to a light emitting device having a substantially square shape or a shape close to a square. In addition, it is possible to provide a region where only the light emitting elements are arranged in a higher density / high integration, and it is possible to realize a light source with high brightness and brightness.
Here, “parallel in the longitudinal direction” means that they are arranged in a line in the longitudinal direction. Usually, in these elements and the like, since the light emitting element has the largest dimension, the protective element and the through hole may be arranged so as not to protrude in the short direction from the width in the short direction of the light emitting element. Is suitable. In particular, it is preferable that the centers of gravity of light emitting elements, protective elements, and through holes (or the centers in the short direction when arranged) are arranged linearly. With such an arrangement, the dimensions in the short direction can be made closer to the minimum. In addition, when the size of the light emitting device in the lateral direction is further reduced or the thickness is reduced, it is usually realized by reducing the thickness of the wall surface and / or the bottom surface.
At this time, if the through hole position is unevenly distributed in one of the short sides, there is a concern that the light emitting device is cracked. On the other hand, as described above, since the light emitting element, the protective element, and the through hole are arranged in the center in the short direction, the protective element (preferably the through hole) is smaller than the light emitting element. Without changing the width of the side, the wall surface can be thickened only in the vicinity thereof. Thereby, the strength of the light emitting device can be improved. In addition, the mounting accuracy can be further improved by arranging the protective element and / or the through hole at the center in the lateral direction.
In addition, the parallel order of a light emitting element, a protective element, and a through hole is not specifically limited, For example, the order of protective element-light emitting element-through hole may be sufficient, the order of protective element-through hole-light emitting element may be sufficient, and light emission may be sufficient. The order of element-protective element-through hole may be used.

In addition to the first and second conductive members, which will be described later, in order to place a light emitting element on the base material, in order to effectively reflect light from the light emitting element, various things such as ensuring heat dissipation of the light emitting element For this purpose, one or more conductive members formed of the same material as the first and second conductive members may be provided on the outer surface (preferably the back surface) or inside thereof (for example, FIG. 1 ( g) 17). The shape and position in this case are not particularly limited, but in particular, in order to ensure heat dissipation, it is preferable to form in a region including directly under the light emitting element.
A base material can be formed by well-known methods, such as sintering of the green sheet on which the molding, the electrically-conductive member, the ceramic material, etc. were laminated | stacked with the 1st and 2nd electrically-conductive member etc. which are mentioned later.

(First and second conductive members)
The base material includes first and second conductive members extending from the surface to the inside. The first and second conductive members are each electrically connected to a pair of electrodes of the light emitting element.
The material which comprises the 1st and 2nd electrically-conductive member is not specifically limited, What is necessary is just to have the electroconductivity which can function as an electrode or a terminal, and can thermally radiate the heat | fever which generate | occur | produces from a light emitting element effectively. It is preferable that it can be used.
Examples of such materials include Ni, Ti, Au, Pt, Pd, W, Co, Au, Mn, V, Cr, Zr, Rh, Cu, Al, Mg, Bi, Sn, Ir, Ga, and Nd. And metals such as Re; alloys of iron-nickel alloys, phosphor bronze, iron-containing copper, etc .; those having a metal plating film of silver, aluminum, copper, gold, etc. on the surface of these metals or alloys, etc. Can be mentioned. Further, it may be a paste-like conductive material in which a refractory metal such as tungsten or molybdenum is contained in a resin binder. These films may be a single layer or a laminated film made of different materials. In particular, in order to obtain a plating film that can be easily manufactured in a thin film shape, for example, a laminated film of copper-Ni-Au, copper-Ni-silver, or the like is preferably formed in this order from the substrate side. The thickness of the first and second conductive members is, for example, about 1 to 100 μm at the portion disposed on the outer surface of the base material.

  The first and second conductive members must be exposed on the surface of the base material supporting the light emitting element from the viewpoint of electrical connection with the electrode of the light emitting element, and the light emitting device is mounted on the mounting substrate. In order to mount, it is preferable to reach the back surface of the base material. In this case, either one or both of the first and second conductive members may extend from the surface of the base material through the side surface to the back surface (for example, the first in FIGS. 1A and 1D). The conductive member 11 and the second conductive member 12) may be extended from the surface of the base material to the back surface through a through hole penetrating from the surface of the base material to the back surface. In addition, when a through hole is formed in a base material and a conductive member passes through the through hole, the conductive member that passes through the through hole may be either an anode electrode or a cathode electrode of the light emitting element.

It is suitable that at least a part of the first and second conductive members is disposed on the back surface other than the concave portion formed on the back surface of the base material described above. It is preferable that the first and second conductive members are respectively disposed on both sides in the longitudinal direction of the recess.
In addition, when the light emitting element support surface of the base material has a recess and a convex portion is formed in the recess, the first and second conductive members are also disposed on the convex portion surface. Is preferred. Thereby, electrical connection with a light emitting element can be easily performed in the convex part surface.

[Protective element]
The light emitting device of the present invention further includes a protective element (see, for example, the protective element 18 in FIG. 1B). The protection element usually has a plane area smaller than that of the semiconductor light emitting element. Moreover, it is preferable that the length of one side of the protective element is smaller than the length of one side of any of the light emitting elements. Accordingly, when the protective elements are arranged in parallel in the light emitting device, the size of the light emitting device can be brought close to the size of the light emitting element, and a light source in which the light emitting device is integrated with high density / high integration can be provided. it can. The type of the protective element is not particularly limited, and may be any known element that is mounted on the light emitting device. For example, an element capable of short-circuiting a reverse voltage applied to the light-emitting element or short-circuiting a forward voltage higher than a predetermined voltage higher than the operating voltage of the light-emitting element, that is, overheating, overvoltage, overcurrent , Protection circuits, electrostatic protection elements and the like. Specifically, a Zener diode, a transistor diode, or the like can be used. In general, the protective element preferably has a size smaller than that of the light emitting element.
In the light emitting device of the present invention, it is preferable that the protective element is placed outside the irradiation range of the light emitted from the light emitting element. Thereby, the light absorption in a protection element can be suppressed. Normally, only one protective element is mounted, but two or more protective elements may be mounted.

[Translucent member]
In the light-emitting device of the present invention, it is preferable that a light-transmitting member covers the light-emitting element and the like in order to protect the light-emitting element and optionally a wire. For example, in the case where the substrate has a light emitting element mounting portion having a recessed shape, a translucent member may be disposed on the recessed portion so as to rise further from the surface of the substrate (FIG. 1 ( e) The translucent member 60 of FIG.
The translucent member is preferably formed of a material that can protect the light emitting element from external force, moisture, and the like, and can protect a wire that secures the connection between the light emitting element and the conductive member.
As a translucent member, epoxy resin, silicone resin, acrylic resin, urea resin fat, polyphthalamide (PPA), polycarbonate resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), ABS resin, phenol resin, PBT resin Examples thereof include transparent resins or glass excellent in weather resistance such as resins such as these or combinations thereof. In particular, even if the transparent resin contains moisture in the translucent covering member during the process or during storage, the moisture contained in the resin is obtained by baking at about 100 ° C. for about 14 hours or more. You can escape to the open air. Therefore, it is possible to prevent water vapor explosion and peeling of the light emitting element and the sealing member described later.
Here, the translucency means a property of transmitting light emitted from the light emitting element to about 70% or more, about 80% or more, about 90% or more, or about 95% or more.

The light transmissive member may contain a diffusing agent or a fluorescent material. The diffusing agent diffuses light and can reduce the directivity from the light emitting element and increase the viewing angle. The fluorescent substance converts light from the light emitting element, and can convert the wavelength of light emitted from the light emitting element to the outside. When the light from the light-emitting element is high-energy short-wavelength visible light, nitrogen-containing CaO—Al ₂ O activated with a perylene derivative, ZnCdS: Cu, YAG: Ce, Eu and / or Cr, which is an organic fluorescent material Various known materials such as inorganic fluorescent materials such as _3- SiO ₂ are used. In the present invention, when white light is obtained, in particular, when a YAG: Ce fluorescent material is used, light from the blue light emitting element and a yellow color which is a complementary color by partially absorbing the light can be emitted depending on the content. The system can be formed relatively easily and reliably. Similarly, when a nitrogen-containing CaO—Al ₂ O ₃ —SiO ₂ fluorescent material activated by Eu and / or Cr is used, the light from the blue light emitting element and a part of the light are absorbed depending on the content. Thus, a red color which is a complementary color can emit light, and a white color can be formed relatively easily and with high reliability.

Hereinafter, a light emitting device of the present invention will be described in detail with reference to the drawings.
Embodiment 1
As shown in FIGS. 1A to 1G, the light emitting device 10 includes a base material 1, a light emitting element 2, and a protective element 18.
The base material 1 is formed of alumina nitride, and the basic outer shape is formed in a rectangular parallelepiped shape with an outer shape in the longitudinal direction of about 5 mm, an outer shape in the short direction of about 3 mm, and a thickness of about 1 mm. Yes.
Near the center of the surface 1 a of the substrate 1, there is a recess 13 on which the light emitting element 2 and the protection element 18 are placed. Two convex portions 14 are formed in parallel to the lateral direction so as to sandwich the vicinity of the center of the recess 13. The position of the upper surface of the convex portion 14 is set slightly lower than the base material surface 1a other than the recess 13, and the width is about 0.22 mm. In addition, the bottom surface is disposed at a position slightly higher than the bottom surface position of the depression 13 near the center in the depression 13 and outside the convex portion 14. A through hole 15 is disposed inside the depression 13 and outside one of the protrusions 14.

  A recess 16 is formed on the back surface 1 b of the substrate 1. The recess 16 is arranged in parallel with the short side direction, straddling the pair of side surfaces 1d and 1f in the longitudinal direction of the base material 1, that is, being opened by the pair of side surfaces 1d and 1f in the longitudinal direction. The through hole 15 described above is disposed in the inside of the recess 16 and substantially in the center of the recess in the short direction.

A cathode electrode is disposed as the first conductive member 11 in the recess 13 on the surface 1 a of the substrate 1. The first conductive member 11 extends to a region other than the light emitting element 2 mounting portion in the recess 13 and reaches the upper surface of the two convex portions 14, the vicinity of the through hole 15, and the inside thereof.
The first conductive member 11 passes through the through hole 15 and penetrates the back surface 1b of the base material 1 and extends from the through hole 15 toward both sides thereof in a direction substantially parallel to the short direction of the base material 1. It is routed around the back surface 1 b of the material 1. One of the first conductive members 11 extending from the through hole 15 branches on the back surface 1b of the base material 1 and is on the side surface 1d in the longitudinal direction of the base material 1, and the other is the side surface in the short direction of the base material 1. It leads to side 1c. The other of the first conductive members 11 extending from the through hole 15 reaches the other longitudinal side surface 1 f side of the substrate 1.

Moreover, it is the surface 1a of the base material 1, and the light emitting element 2 mounting part in the recess 13 and the side surface of the recess 13 are drawn around, and the recess 13 is outside the convex portion 14 (the through hole 15 is formed). The anode electrode as the second conductive member 12 is disposed on the protection element 18 mounting portion on the side where the protective element 18 is not disposed and is electrically insulated from the first conductive member 11.
The second conductive member 12 extends from the inside of the recess 13 of the substrate 1 along one side surface 1d in the longitudinal direction, passes through the protection element 18 mounting portion, and further has a height at the center portion of the side surface 1e in the short side direction. It is drawn in the direction and reaches the back surface 1b. Further, in the other lateral side surface 1c, the vicinity of the end is drawn in the height direction and reaches the back surface 1b.
Note that the back surface 1b of the base material 1 is provided between the concave portion 16 and the second conductive member 12 on the side surface 1e side in the short direction, and in the portion corresponding to the portion immediately below the light emitting element 2, The third conductive member 17 is formed with a size slightly shorter than the length in the short direction so as not to short-circuit with the second conductive members 11 and 12. The third conductive member 17 functions effectively as a heat radiating member.
For example, the first to third conductive members 11, 12, and 17 are formed as stacked films by plating in the stacking order of copper (7 μm) -Ni (6 μm) -Au (0.3 μm) from the base material side. .

  The lower side surface (for example, a height of about 40% from the bottom) of the base material 1 is substantially perpendicular to the front and back surfaces of the base material 1, and the upper side surface (for example, a height of about 60% from the top). Is a tapered shape inclined inward by about 5 °. Accordingly, when the light emitting device is mounted on the mounting substrate, the light emitting device 10 can be reliably gripped from the side surface direction.

The light-emitting element 2 is formed of a laminated body of InGaAlN-based nitride semiconductor layers, has an emission wavelength of 385 nm, has a chip size of 1 mm × 1 mm, and a chip height of 300 μm (unit). The pair of electrodes are respectively formed on the upper and lower surfaces of the light emitting element, and are mounted on the substrate 1 face up.
The light emitting element 2 is die-bonded on the second conductive member 12 by using a conductive paste such as silver, gold, or palladium, and is electrically connected to the electrode on the back surface side of the light emitting element 2. The first conductive member 11 is electrically connected to the first conductive member 11 by wire bonding using a gold wire 19 by two pad electrodes formed on the surface side of the light emitting element on the upper surface of the convex portion 14 in the hollow portion 13.
The second conductive member 12 is extended into the recess 13 in addition to the portion where the light emitting element 2 is placed, and the protective element 18 is mounted thereon and is electrically connected to the protective element 18. The protective element 18 has a surface-side electrode electrically connected to the first conductive member 11.

That is, the light-emitting element 2 is disposed at the substantially center of the upper surface of the substrate 1, and the protective element 18 is disposed adjacent to the light-emitting element 2 (with the convex portion 14 interposed). A through hole 15 is disposed adjacently (with the convex portion 14 in between). In these arrangements, the center of gravity of the light emitting elements and the center of the side corresponding to the short direction of the light emitting elements are arranged in a straight line substantially at the center in the short direction of the light emitting device.
The hollow portion 13 of the substrate 1 is hollow, and the outermost surface of the substrate is covered with a glass plate or a glass lens (not shown). Or you may be covered with the translucent member 50 which consists of an epoxy resin etc., for example.

As described above, by arranging the semiconductor light emitting element, the protective element, and the through hole in the longitudinal direction in a specific base material, the dimension of the light emitting element in one direction, in particular, the short side direction is made as close as possible to that of the light emitting element. Thus, the light emitting element can be further miniaturized, and a light source or the like that can supply light with higher brightness and brightness can be realized.
In addition, since the light emitting element, the protective element, and the through hole are arranged almost in the center in the short side direction, the protective element and the through hole are smaller than the light emitting element, so that the width on the short side is not changed. The wall surface can be thickened only in the vicinity of, so that the strength of the light emitting device can be further improved and the mounting accuracy can be further improved.

Embodiment 2
In the light emitting device, as shown in FIG. 2, the position of the concave portion 26 and the position of the through hole 25 on the back surface 20 b of the base material 20 are moved to the central portion in the longitudinal direction. And the shape and arrangement of the back surface 20b of the second conductive member 22 are different.
In addition, with the change in the shape and arrangement of the first conductive member 21 and the second conductive member 22 on the back surface 20b, a through hole is formed on the support surface side of the light emitting element corresponding to the arrangement on the back surface 20b. The configuration is substantially the same as that of the light-emitting device 10 of Embodiment 1 except that the positions of the light-emitting elements 25 and the light-emitting elements are interchanged.
Note that the end portions on the side surface 20c side of the first conductive member 21 and the second conductive member 22 are both the first conductive member 11 and the second conductive member 12 like the end portions on the side surface 1c side in the first embodiment. May be arranged narrowly.
Further, the end of the second conductive member 21 on the side surface 20e side may be arranged with a narrow width like the second conductive member 22 in the first embodiment.
With such a configuration, the same effect as in the first embodiment can be obtained.

Embodiment 3
As shown in FIG. 3, in this light emitting device, the shape of the concave portion 36 on the back surface 30b of the base material 30 is different, and accordingly, the first conductive member 31 and the second conductive member 32 on the side surface 30c side in the short side direction. The configuration is substantially the same as that of the light-emitting device 10 of Embodiment 1 except that the routing is different.
That is, the recess 36 is the back surface 30b of the base material 30 and is opened only on the side surface 30c side in the short direction, and is surrounded by the back surface 30b in two directions in the short direction and one direction in the long direction. Yes.
Note that the end portion on the side surface 30e side of the second conductive member 32 may be arranged with a narrow width like the second conductive member 12 in the first embodiment.
Such a configuration has the same effect as that of the first embodiment.

Embodiment 4
As shown in FIG. 4, this light emitting device has substantially the same configuration as the light emitting device 10 of the first embodiment except that the shape of the recess 46 on the back surface 40 b of the substrate 40 is different.
That is, the recess 46 does not straddle the pair of side surfaces 40d and 40f in the longitudinal direction, and is open only on the side surface 1d side, and is surrounded by the back surface 40b in two directions in the longitudinal direction and one direction in the lateral direction. ing.
The end portions on the side surface 40c side of the first conductive member 41 and the second conductive member 42 are both the first conductive member 11 and the second conductive member 12 like the end portions on the side surface 1c side in the first embodiment. May be arranged narrowly.
Further, the end of the second conductive member 41 on the side surface 40e side may be arranged with a narrow width like the second conductive member 12 in the first embodiment.
Such a configuration has the same effect as that of the first embodiment.

  The light-emitting device of the present invention can be used for various light sources such as illumination light sources, various indicator light sources, in-vehicle light sources, display light sources, liquid crystal backlight light sources, traffic lights, in-vehicle components, and signboard channel letters. In addition, it can be used for a light source that is required to be lighter by being particularly miniaturized and arranged at an extremely high density.

1, 20, 30, 40 Base material 1a Front surface 1b, 20b, 30b, 40b Back surface 1c, 1e, 20c, 20e, 30c, 30e, 40c, 40e Side surface in short direction 1d, 1f, 20d, 20f, 30d, 30f 40d, 40f Longitudinal side surface 2 Light emitting element 10 Light emitting device 11, 21, 31, 41 First conductive member 12, 22, 32, 42 Second conductive member 13 Recessed portion 14 Protruding portion 15, 25, 35 Through hole 16 , 26, 36 Recessed parts 17, 37 Third conductive member 18 Protective element 19 Gold wire 50 Translucent member

Claims (5)

A semiconductor light emitting device;
A protective element having a smaller planar area than the semiconductor light emitting element;
A base having a front surface for supporting the semiconductor light emitting element and the protective element, two pairs of side faces extending in the longitudinal direction and the short side and facing each other, and a back face having a recess extending only to the side face extending in the longitudinal direction. Including
A light-emitting device having a through hole penetrating in the rear surface of the recess from the table surface of the substrate,
The light-emitting device, wherein the semiconductor light-emitting element, the through hole, and the protective element are arranged in this order in the longitudinal direction and so that the centers in the short-side direction are arranged in a straight line. Wherein the substrate, the light emitting device according to claim 1 comprising first and second conductive members on a side surface extending the in the transverse direction.   The light-emitting device according to claim 1, wherein the first and second conductive members are exposed on the back surface of the base material.   The light emitting device according to any one of claims 1 to 3, wherein a third conductive member is disposed between the first and second conductive members on the back surface of the base material. The semiconductor light emitting device and the bottom surface of the protective element is electrically connected to the first conductive member, any of the semiconductor top surface of the light emitting elements are connected the second conductive member and electrically claim 2-4 The light emitting device according to one.

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