JP2013008744A - Semiconductor light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting device with a configuration in which a plurality of light-emitting elements are stacked such that the light-emitting elements are parallel to one another along one direction with respect to a surface of a substrate.SOLUTION: Light-emitting elements 11, 12 are provided so as to stand up along a height direction Z from a surface 2f of a substrate 2 at a level lower than a light-emitting element 13. The light-emitting elements 11, 12 comprise a supporting member 5 which is opposite to at least two facing side surfaces 11a, 11b, 12a, 12b. Supporting portions 5a, 5b, which are parallel to the light-emitting element 11, on which the light-emitting elements 12, 13 provided at a level higher than the light-emitting layer 11 provided at the lowest level are mounted, are formed in the supporting member 5.

Description

  The present invention relates to a semiconductor light emitting device in which a plurality of light emitting elements are stacked in one direction on one surface of a substrate.

  In a semiconductor light emitting device, a configuration in which a plurality of light emitting elements are stacked along one direction with respect to one surface of a substrate is well known, and is disclosed in Patent Document 1, for example.

  In Patent Document 1, a first-stage transparent light-emitting element is mounted on one surface of an electric substrate, and two stages of the same size as the first-stage light-emitting element are placed on the first-stage light-emitting element via a transparent resin. A transparent light-emitting element of the eye is laminated, and a third-stage transparent light-emitting element having the same size as the first-stage and second-stage light-emitting elements is laminated on the second-stage light-emitting element via a transparent resin. A configuration is disclosed in which the bonding pads of each light-emitting element are electrically connected to the electrodes of the electric substrate via bonding wires, respectively.

  In such a configuration, the light emitted from the first-stage light-emitting element passes through the second-stage and third-stage light-emitting elements and is irradiated to the subject, and is emitted from the second-stage light-emitting element. The emitted light passes through the third-stage light-emitting element and is irradiated on the subject, and the light emitted from the third-stage light-emitting element is directly irradiated on the subject.

JP 2008-130777 A

  By the way, in the structure which laminates | stacks the some light emitting element disclosed by patent document 1 along one direction, in order to prevent that the light emitted from each light emitting element is scattered, each light emission is transmitted through transparent resin. It is necessary to stack the elements so that they are parallel to each other. In addition, if the light emitted from each light emitting element is scattered, the luminance is lowered and the light emission characteristics are deteriorated such as color unevenness.

  However, since a bonding pad or the like is provided on the surface opposite to the electric substrate of each light emitting element, it does not have a flat shape, so that each light emitting element is parallel even if a transparent resin is used. In other words, it is difficult to stack the transparent resin, in other words, it is difficult to cure the transparent resin while maintaining the parallelism of the light emitting elements.

  The present invention has been made in view of the above problems, and a semiconductor light emitting device having a configuration in which a plurality of light emitting elements can be stacked on one surface of a substrate so that each light emitting element is parallel along one direction. An object is to provide an apparatus.

  In order to achieve the above object, a semiconductor light emitting device according to an aspect of the present invention is a semiconductor light emitting device in which a plurality of light emitting elements are stacked in one direction with respect to one surface of a substrate, and the one direction from the one surface of the substrate. A support member facing at least two side surfaces facing each other in each of the light emitting elements located below the light emitting element of at least the uppermost layer among the light emitting elements provided to stand along A support portion parallel to the lowermost light emitting element on which the light emitting elements positioned above the lowermost light emitting element mounted on the substrate are mounted on a support member. Is formed.

  ADVANTAGE OF THE INVENTION According to this invention, the semiconductor light-emitting device which comprises the structure which can be laminated | stacked so that each light emitting element may become parallel along one direction with respect to one surface of a board | substrate can be provided.

Plan view of the semiconductor light emitting device of the first embodiment Sectional drawing of the semiconductor light-emitting device along the II-II line in FIG. The top view of the semiconductor light-emitting device which shows the example which formed the support part of the supporting member of FIG. 1 in the shape of a rail The top view of the semiconductor light-emitting device which shows the example which formed the support part of the support member of FIG. 1 in the shape which supports four corners of the bottom face of a light emitting element. The top view of the semiconductor light-emitting device of 2nd Embodiment Sectional drawing of the semiconductor light-emitting device along the VI-VI line in FIG. The top view of the semiconductor light-emitting device of 3rd Embodiment Sectional drawing of the semiconductor light-emitting device along the VIII-VIII line in FIG. Sectional view of the semiconductor light-emitting device along the line IX-IX in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. The drawings are schematic, and it should be noted that the relationship between the thickness and width of each member, the ratio of the thickness of each member, and the like are different from the actual ones. Of course, the part from which the relationship and ratio of a mutual dimension differ is contained.

(First embodiment)
1 is a plan view of the semiconductor light-emitting device of the present embodiment, FIG. 2 is a cross-sectional view of the semiconductor light-emitting device along the line II-II in FIG. 1, and FIG. 3 is a support portion of the support member of FIG. FIG. 4 is a plan view of a semiconductor light emitting device showing an example in which the support portion of the support member of FIG. 1 is formed in a shape that supports the four corners of the bottom surface of the light emitting element. FIG.

  As shown in FIGS. 1 and 2, the semiconductor light emitting device 1 includes a substrate 2, and a plurality of rectangular light emitting elements 11 having the same size are formed on a surface 2 f that is one surface of the substrate 2. , 12 and 13 are stacked along the height direction Z which is one direction.

  Specifically, the lowermost light emitting element 11 is mounted on the surface 2f by bonding or the like, and the light emitting element 12 is disposed on the upper layer in the height direction Z of the light emitting element 11 via the transparent resin 7. 11, and the uppermost light-emitting element 13 is positioned in parallel with the light-emitting elements 11 and 12 through the transparent resin 7 in the upper layer of the light-emitting element 12 in the height direction Z.

  Examples of the adhesive that adheres the light emitting element 11 to the surface 2f include a resin having a good light reflection efficiency such as a silver paste (or nanoparticles). Examples of the transparent resin 7 include a thermosetting resin, a UV curable resin, a UV heat combined curing resin, and the like, and examples of the material include an epoxy resin and an acrylic resin. Furthermore, the resin 7 is transparent because the light emitted from the light emitting elements 11 and 12 is irradiated upward in the height direction Z, and thus the light needs to pass through.

  Here, a specific configuration in which the light emitting elements 11 to 13 are stacked along the height direction Z so as to be parallel will be described.

  As shown in FIG. 2, the two support members 5 facing the two side surfaces 11a, 11b, 12a, 12b of the light emitting elements 11, 12 facing the surface 2f of the substrate 2 are arranged in the height direction Z from the surface 2f. Are provided by bonding or the like. In addition, as a material which comprises the supporting member 5, resin (epoxy, acrylic, glass, plastics, etc.) or metals (copper, aluminum, brass, etc.) are mentioned.

  Examples of the adhesive that bonds the two support members 5 to the surface 2f include UV curable resins or UV heat combined curable resins, and examples of the material include epoxy and acrylic. .

  In FIG. 2, the gap 9 is formed between the side surfaces 11 a, 11 b, 12 a, 12 b and the two support members 5, but the gap 9 may be omitted. That is, the two support members 5 may be in contact with the side surfaces 11a, 11b, 12a, and 12b.

  The two support members 5 have, at the top in the height direction Z, a support portion 5a that protrudes inward by a predetermined length W so as to be parallel to the light emitting element 11 in the direction Y, and in the height direction. Between the top in Z and the surface 2f, there is also a support portion 5b protruding inward by a predetermined length W so as to be parallel to the light emitting element 11 in the direction Y.

  The support portions 5a and 5b formed on one support member 5 and the support portions 5a and 5b formed on the other support member 5 are located at the same height in the height direction Z from the surface 2f. Therefore, the support portions 5a and the support portions 5b face each other in the direction Y.

  The support 5b is a part on which the bottom surface 12t of the light emitting element 12 is placed, and the support part 5a is a part on which the bottom surface of the light emitting element 13 is placed.

  As shown in FIG. 3, the support portion 5 a is formed in a rail shape along the direction X so as to have a width that is the same as or smaller than the width of the light emitting element 13 in the direction X. Moreover, when the support part 5a is formed in the same width | variety as the width | variety of the direction X of the light emitting element 13, the support parts 5a and 5b are utilized for positioning of each light emitting element 11-13.

  Further, the support portion 5a may be configured in a rail shape along the direction X so that the vicinity of the edge portions of the side surfaces 13a and 13b on the bottom surface 13t of the light emitting element 13 is placed. As shown in FIG. 4, the light emitting element 13 may have a configuration in which four corners on the bottom surface 13t are scattered. This also applies to the support portion 5b. Furthermore, the shapes of the support portions 5a and 5b are not limited to the shapes shown in FIGS.

  From the above, the light emitting element 11 is mounted on the surface 2 f, the bottom surface 12 t of the light emitting element 12 is placed on the support portion 5 b of the support member 5, and the bottom surface 13 t of the light emitting element 13 is placed on the support portion 5 a of the support member 5. Thus, the light emitting elements 11 to 13 are stacked along the height direction Z so as to be parallel.

  As shown in FIG. 1, the p-side electrode (not shown) of the light emitting element 11 is electrically connected to the electrode 3 a formed on the surface 2 f by wire bonding using the wire 21. The p-side electrode (not shown) is also electrically connected to the electrode 3b formed on the surface 2f by wire bonding using the wire 22, and the p-side electrode 13p of the light emitting element 13 also uses the wire 23. It is electrically connected to the electrode 3c formed on the surface 2f by wire bonding.

  Further, the n-side electrodes 11n, 12n, 13n of the light emitting elements 11, 12, 13 are electrically connected to the common electrode 4 formed on the surface 2f by wire bonding using the wires 25a to 25c.

  On the surface 2f, the electrodes 3a to 3c are side surfaces 11c to 13c that are 90 ° different from the side surfaces 11a to 13a and 11b to 13b in the stacked light emitting devices 11 to 13 (the side surfaces 11c and 12c are not shown). The common electrode 4 is 90 ° different from the side surfaces 11a to 13a and 11b to 13b in the stacked light emitting elements 11 to 13, and the side surfaces 11d to 13d facing the side surfaces 11c to 13c. (Side surfaces 11d and 12d are not shown).

  That is, the electrodes 3 a to 3 c and the common electrode 4 are located on a side different from the two support members 5 by 90 °. This is because if the electrodes 3a to 3c and the common electrode 4 are positioned on the same side as the two support members 5, the two support members 5 hinder wire bonding.

Next, a manufacturing process of the semiconductor light emitting device 1 having such a configuration will be briefly described.
First, the light-emitting element 11 is bonded and fixed to the surface 2f of the substrate 2, and the p-side electrode of the light-emitting element 11 is wire-bonded to the electrode 3a via the wire 21, and the n-side electrode is commonly used via the wire 25a. Wire bonding is performed on the electrode 4.

  Next, the two support members 5 are bonded and fixed to the above-described positions on the surface 2f. Thereafter, the transparent resin 7 is applied to the upper surface of the light emitting element 11 by a dispenser, an inkjet, or the like, and the light emitting element 12 is placed between the two support members 5 in the Y direction, with the support portions 5a and 5b in the height direction Z. Between the X direction, the bottom surface 12t is placed on the support portion 5b, and the transparent resin 7 is cured.

  Further, after the transparent resin 7 is cured, the p-side electrode of the light emitting element 12 is wire-bonded to the electrode 3b via the wire 22, and the n-side electrode is wire-bonded to the common electrode 4 via the wire 25b.

  Next, the transparent resin 7 is applied onto the light emitting element 12 by the same method as described above, and the light emitting element 13 is lowered from above in the height direction Z and placed on the support portion 5b. After the transparent resin 7 is cured, the p-side electrode 13p of the light emitting element 13 is wire-bonded to the electrode 3c via the wire 23, and the n-side electrode 13n is wire-bonded to the common electrode 4 via the wire 25c. . In this way, the semiconductor light emitting device 1 is manufactured.

  Thus, in the present embodiment, in the configuration of the semiconductor light emitting device 1 in which the light emitting elements 11 to 13 are stacked along the height direction Z on the surface 2f of the substrate 2 via the transparent resin 7, the substrate 2 It was shown that two support members 5 parallel to the light emitting element 11 fixed to the surface 2f of the light emitting element 11 were used, and the light emitting elements 11 to 13 were stacked along the height direction Z so as to be parallel to each other. .

  According to this, since each light emitting element 11-13 is certainly located in parallel by the support parts 5a and 5b of the two support members 5, the light emitted from each light emitting element 11-13 is scattered. Therefore, the luminance is not lowered, and the light emission characteristics such as color unevenness are not deteriorated. That is, light is efficiently emitted from each of the light emitting elements 11 to 13.

  From the above, the semiconductor light emitting device 1 having a configuration in which the plurality of light emitting elements 11 to 13 can be stacked along the height direction Z with respect to the surface 2 f of the substrate 2. Can be provided.

(Second Embodiment)
FIG. 5 is a plan view of the semiconductor light-emitting device of the present embodiment, and FIG. 6 is a cross-sectional view of the semiconductor light-emitting device along the VI-VI line in FIG.

  The structure of the semiconductor light emitting device of the second embodiment is such that the two support members are the uppermost light emitting elements as compared with the semiconductor light emitting device of the first embodiment shown in FIGS. The point which is formed in the length which opposes a side surface differs in the point by which the adhesive agent is inject | poured between the two support members and the side surface of each light emitting element. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  As shown in FIGS. 5 and 6, in the present embodiment, the two support members 5 have lengths facing the side surfaces 13 a and 13 b facing the light emitting element 13 located in the uppermost layer, specifically, The top portions in the height direction Z of the two support members 5 are formed to have the same height as the top surface of the light emitting element 13. The two support members 5 may be formed to have a length that protrudes upward in the height direction Z from the upper surface of the light emitting element 13.

  In the present embodiment, the thickness Y2 in the direction Y of the support member 5 is formed thicker than the thickness Y1 in the direction Y of the support member 5 in the first embodiment (Y2> Y1). This is to improve the heat radiation effect described later from the support member 5.

  Furthermore, in the present embodiment, a heat radiation adhesive 30 is injected into the gap 9 between the side surfaces 11a to 13a and 11b to 13b of the light emitting elements 11 to 13 and the two support members 5. . Examples of the adhesive 30 include an epoxy resin containing a metal filler, a highly heat conductive resin such as an acrylic resin, and a plastic resin.

  The adhesive 30 has a function of transferring heat generated from the light emitting elements 11 to 13 to the two support members 5 as the light emitting elements 11 to 13 emit light. Accordingly, the two support members 5 are made of a heat-dissipating material that dissipates the heat transferred from the light-emitting elements 11 to 13, specifically, a metal such as aluminum, copper, or brass, a high thermal conductive resin, or the like. It is preferable that it is comprised from these.

  Although not shown, a heat radiating metal plate may be provided on the back surface of the substrate 2 in order to further improve heat dissipation. In addition, two support members 5 penetrating the substrate 2 in the height direction Z may be directly connected to the metal plate for heat dissipation. Other configurations are the same as those in the first embodiment.

  According to such a configuration, since the two support members 5 are formed to have a length facing the side surfaces 13a and 13b of the uppermost light emitting element 13, the light emitting element 13 can be reliably supported. There is an advantage that the light emitting element 13 is less inclined than the first embodiment.

  Moreover, since the heat | fever of the light emitting elements 11-13 can be radiated | emitted from the two support members 5 through the adhesive agent 30 from the side surfaces 11a-13a, 11b-13b of the light emitting elements 11-13, the light emitting elements 11-13. The heat radiation efficiency of the light emitting elements 11 to 13 can be improved, the luminance can be further improved, and the life of the light emitting elements 11 to 13 can be increased.

  Therefore, in the configuration of the semiconductor light emitting device 1 of the first embodiment, heat may be radiated from the two support members 5 by injecting the adhesive 30 into the gap 9. Other effects are the same as those of the first embodiment.

(Third embodiment)
7 is a plan view of the semiconductor light emitting device of the present embodiment, FIG. 8 is a cross-sectional view of the semiconductor light emitting device along the line VIII-VIII in FIG. 7, and FIG. 9 is along the line IX-IX in FIG. It is sectional drawing of a semiconductor light-emitting device. 8 and 9 are simplified for easy understanding of the drawings.

  The structure of the semiconductor light emitting device of the third embodiment includes the semiconductor light emitting device of the first embodiment shown in FIGS. 1 to 4 and the semiconductor light emitting device of the second embodiment shown in FIGS. The difference is that the p-side electrode and the n-side electrode of the plurality of light-emitting elements are electrically connected to the electrodes of the substrate using side wirings provided on the side surfaces of the plurality of light-emitting elements. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first and second embodiments, and the description thereof will be omitted.

  As shown in FIGS. 8 and 9, in the semiconductor light emitting device of this embodiment, the electrical connection between the p-side electrode 11p of the light-emitting element 11 and the electrode 3a, the p-side electrode 12p and the electrode 3b of the light-emitting element 12 are performed. The electrical connection between the p-side electrode 13p and the electrode 3c of the light-emitting element 13 and the electrical connection between the n-side electrodes 11n to 13n of the light-emitting elements 11 to 13 and the common electrode 4 are wires. And using the side wirings 51 to 53 and 55 made of a conductor.

  Specifically, as shown in FIGS. 7 and 8, the p-side electrode 11 p and the electrode 3 a of the light emitting element 11 are side surfaces 11 a to 13 a and 11 b to 13 b facing the two support members of the light emitting elements 11 to 13. Are electrically connected by side wirings 51 formed on the side surfaces 11c to 13c, and the p-side electrode 12p and the electrode 3b of the light emitting element 12 are connected to the side surfaces 11c to 13c. The side wiring 52 formed is electrically connected, and the p-side electrode 13p and the electrode 3c of the light emitting element 13 are electrically connected by the side wiring 53 formed on the side surfaces 11c to 13c. .

  As shown in FIGS. 7 and 9, the n-side electrodes 11 n to 13 n and the common electrode 4 of the light-emitting elements 11 to 13 are side surfaces 11 a to 13 a and 11 b that face the two support members of the light-emitting elements 11 to 13. Are electrically connected by a side surface wiring 55 formed on a side surface different from that of the side surfaces 11d to 13d, specifically, the side surfaces 11d to 13d.

  The side wirings 51 to 53 and 55 are formed on the side surfaces 11c to 13c and 11d to 13d of the light emitting elements 11 to 13, for example, by inkjet. Although not shown, the side wirings 51 to 53 and 55 are covered with an insulator.

  Moreover, in order to protect the connection part of the side wirings 51-53, 55 with respect to the electrodes 3a-3c and the common electrode 4 mechanically, physically, and environmentally, an underfill may be provided.

  Further, as shown in FIGS. 7 to 9, the side surfaces 11 c to 13 c and 11 d to 13 d of the light emitting elements 11 to 13 and the two support members 5 are covered with a heat sink 41 in a circumferential shape. Moreover, between the heat sink 41 and the side surfaces 11c to 13c and 11d to 13d of the light emitting elements 11 to 13, between the two support members 5 and the side surfaces 11a to 13a and 11b to 13b of the light emitting elements 11 to 13, A heat radiation adhesive 30 is injected. Other configurations are the same as those of the first and second embodiments described above.

  According to such a configuration, it is not necessary to use a wire for the electrical connection between each of the light emitting elements 11 to 13 and the electrodes 3a to 3c and the common electrode 4, so that light emission is generated by being pulled by the wire by wire bonding. In addition to preventing the elements 11 to 13 from being tilted, a heat radiating plate can be provided around the entire light emitting elements 11 to 13, and thus further radiates heat than the first to third embodiments described above. Therefore, the luminance can be further improved and the lifetime of the light emitting elements 11 to 13 can be increased.

  In addition, since the side wirings 51 to 53 and 55 are used, it is not necessary to connect on the upper surface of the light emitting elements 11 to 13 as in the case of connection using wires, so that the mounting height of the semiconductor light emitting device 1 is described above. It can be made lower than in the first and second embodiments. Other effects are the same as those of the first and second embodiments described above.

  Hereinafter, modifications will be described. In the present embodiment described above, the side wirings 51 to 53 and 55 are formed in addition to the two supporting members 5. However, the side wirings 51 to 53 and 55 themselves may also serve as the supporting members. It is.

  In addition, the side wirings 51 to 53 and 55 are provided on the side surfaces 11c to 13c and 11d to 13d different from the side surfaces 11a to 13a and 11b to 13b of the light emitting elements 11 to 13 with which the two support members 5 are opposed. Of course, the present invention is not limited to this, and it may be provided on the side surfaces 11a to 13a and 11b to 13b.

  In the first to third embodiments described above, the case where the three light emitting elements 11 to 13 are stacked along the height direction Z on the surface 2f of the substrate 2 has been described as an example. Needless to say, the number of light emitting elements is not limited to three.

  Further, the two support members 5 are shown to be provided at positions facing the two side surfaces 11a to 13a and 11b to 13b facing each other of the light emitting elements 11 to 13. However, the present invention is not limited to this, and for example, shown in FIGS. If a structure is used, you may further provide in the position which opposes the two side surfaces 11c-13c and 11d-13d which the light emitting elements 11-13 face each other. That is, four may be provided.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor light-emitting device 2 ... Board | substrate 2f ... One side of board | substrate 5 ... Supporting member 5a ... Supporting part 5b ... Supporting part 9 ... Gap 11 ... Lowermost light emitting element 11a-11d ... Side face 12 ... Light emitting element 12a-12d ... Side face 13 ... Light emitting element of uppermost layer 13a-13d ... Side face 30 ... Adhesive 51 ... Side face wiring 52 ... Side face wiring 53 ... Side face wiring 55 ... Side face wiring Z ... Height direction (one direction)

Claims (6)

A semiconductor light emitting device in which a plurality of light emitting elements are stacked in one direction with respect to one surface of a substrate,
At least two side surfaces facing each other in each of the light emitting elements that are provided to stand up along the one direction from the one surface of the substrate and that are at least lower than the uppermost light emitting element. Comprising opposing support members,
A support parallel to the light emitting element of the lowermost layer on which the light emitting elements positioned above the light emitting element of the lowermost layer mounted on the substrate are mounted on the support member. A semiconductor light emitting device in which a portion is formed.   2. The semiconductor light emitting device according to claim 1, wherein the support member further faces at least two side surfaces of the uppermost light emitting element facing each other. A gap is formed between the support member and the side surface of the light emitting element facing the support member,
The semiconductor light emitting device according to claim 1, wherein an adhesive that transfers heat of the light emitting element to the support member is injected into the gap.   4. The semiconductor light emitting device according to claim 1, wherein the support member is made of a material having a heat dissipation property to dissipate heat transferred from the plurality of light emitting elements. 5. .   5. The semiconductor light emitting device according to claim 1, wherein each of the light emitting elements is electrically connected to the substrate by wire bonding.   Each of the light emitting elements is electrically connected to the substrate by a side wiring on the side surface or a side surface different from the side surface to which the support member of each light emitting element is opposed. 5. The semiconductor light emitting device according to claim 4.

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