JP2008085296A - Light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device excellent in reliability. <P>SOLUTION: The present invention relates to a light emitting device including: an insulated substrate provided with first and second electrodes on a plane; a light-emitting element which is placed on the plane and electrically connected with the first and second electrodes; a protecting element placed within a first recessed opening that is recessed from the plane side; and a light transmissible member sealing the light-emitting element and the protecting element, wherein the first recessed opening includes third and fourth electrodes electrically linked with the first and second electrodes on a bottom surface and the protecting element is electrically connected with the third and fourth electrodes. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a surface-mounted light-emitting device used for a lighting fixture, a display, a backlight of a mobile phone, a moving image illumination auxiliary light source, and other general consumer light sources.

  A surface-mounted light-emitting device using a light-emitting element emits light of a bright color that is small and power efficient. In addition, since this light emitting element is a semiconductor element, there is no fear of a broken ball. Further, it has excellent initial driving characteristics and is strong against vibration and repeated on / off lighting. Because of such excellent characteristics, light-emitting devices using light-emitting elements such as light-emitting diodes (LEDs) and laser diodes (LDs) are used as various light sources.

  In such a surface-mounted light-emitting device, when a device that is stronger against electrostatic withstand voltage is required, a protective element such as a Zener diode is electrically connected in the light-emitting device adjacent to the light-emitting element. FIG. 8 is a schematic cross-sectional view of a light-emitting device 800 shown as an example of the prior art. FIG. 9 is a schematic cross-sectional view of a light-emitting device 900 shown as another example of the prior art.

For example, as shown in FIG. 8, the first electrode 802a and the second electrode 802b are provided on the plane of the insulating substrate 803, and a pair of positive and negative electrodes is provided on the top surface of the tip of the first electrode 802a. The chip 801 is fixed. One electrode of the LED chip 801 is connected to the first electrode 802a and the other electrode is connected to the second electrode 802b by wires. Further, a protection element chip 804 having electrodes on both the upper and lower surfaces is placed at the tip of the second electrode, and the upper surface side electrode of the protection element 804 is connected to the first electrode 802a by the wire 808, and the lower surface side. The electrode is connected to the second electrode with a conductive adhesive. The LED chip 801 and the protection element 804 connected in this way are sealed with a translucent member 805.
Japanese Patent Laid-Open No. 11-54804

  Further, in Patent Document 1, a recess 906 is formed under the protective element 804 so that the height of the protective element 804 is lower than the height of the light emitting element 801 as in the light emitting device of FIG. It is disclosed that if the protective element 804 is placed, the influence of light blocking by the protective element 804 can be reduced.

  However, the light emitting device as shown in FIG. 9 tends to be significantly less reliable than the light emitting device of FIG. Specifically, since the wire 808 is lifted and bonded from the protective element 804 in the recess 906 to the electrode 802a above the protective element 804, the amount of the translucent member 805 disposed below the wire 808 is reduced. Increase. For this reason, the load on the wire 808 due to repeated expansion and contraction of the translucent member 805 increases due to the thermal cycle of the light emitting device during the manufacturing process and use, and thus the wire 808 is significantly deteriorated.

  Therefore, an object of the present invention is to provide a light emitting device that can have excellent reliability and optical characteristics.

  The light emitting device of the present invention includes an insulating substrate provided with a first electrode and a second electrode on a plane, and is placed on the plane and electrically connected to the first electrode and the second electrode. A light-emitting device having a connected light-emitting element, a protective element placed in a first concave opening recessed from the plane side, and a light-transmitting member that seals the light-emitting element and the protective element. The first concave opening has a third electrode and a fourth electrode that are electrically connected to the first electrode and the second electrode, respectively, on the bottom surface. It is characterized by being electrically connected to the third electrode and the fourth electrode.

  Further, when the protection element is electrically connected to at least one of the third electrode or the fourth electrode by a wire, the wire may be accommodated in the first concave opening. Good.

  The insulating substrate has a second concave opening substantially the same shape as the first concave opening on the plane side, and the first concave opening and the second concave opening are These may be opposed to a pair of external connection electrodes provided on the bottom surface side of the insulating substrate. The light emitting element is preferably disposed between the first concave opening and the second concave opening.

  Further, the arrangement direction of the external connection electrodes may be substantially perpendicular to the wire tension direction. Alternatively, when the insulating substrate is viewed in plan, the tension direction of the wire connected to the light emitting element or the protective element is the central axis in the longitudinal direction of the first concave opening or the second concave opening. It is preferable that the directions are substantially the same.

  The translucent member preferably includes a convex portion disposed on the light emitting element and a flat portion extending on the insulating substrate at a side of the convex portion. .

  The light-emitting element is covered with a wavelength conversion member that absorbs at least part of light from the light-emitting element and converts it into other light, and the convex of the translucent member is covered so as to cover the wavelength conversion member. It is preferable that a portion is provided. The thickness of the flat portion is preferably thinner than the thickness of the wavelength conversion member.

  The convex part of the translucent member is a thick part protruding from the upper surface of the flat part, and the boundary line between the convex part and the flat part is the first concave opening or the second part. It is preferable that a part of the translucent member disposed on the concave opening and including the boundary line is extended into the first concave opening or the second concave opening.

  According to the light emitting device of the present invention, since the protective element is electrically connected in the concave opening recessed from the light emitting element mounting surface, it is possible to have excellent reliability and optical characteristics. Further, in the present invention, since the translucent member is firmly fixed to the insulating substrate, the concave opening for accommodating the protective element can also be used as a shape for obtaining the anchor effect. As described above, according to the present invention, it is not necessary to provide a concave opening for an anchor in the insulating substrate separately from the concave opening for accommodating the protective element. It can be a device.

The best mode for carrying out the present invention will be described below with reference to the drawings. However, the form shown below illustrates the light-emitting device for embodying the technical idea of the present invention, and the light-emitting device of the present invention is not limited to the following.
Further, the present specification by no means specifies the members shown in the claims as the members of the embodiments. The dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments are not intended to limit the scope of the present invention only to the description unless otherwise specified. It's just an example. In addition, the size, positional relationship, and the like of members illustrated in each drawing may be exaggerated for clarity of explanation. Further, in the following description, the same name and reference sign indicate the same or the same members, and detailed description will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing.

  FIG. 1 is a schematic perspective view of a light emitting device of the present invention, and FIG. 2 is a schematic plan view of FIG. 3 is a schematic perspective view of the light emitting device according to the second embodiment, FIG. 4 is a schematic cross-sectional view taken along line AA in FIG. 3, and FIG. It is a typical bottom view. Furthermore, FIG. 6 and FIG. 7 are schematic perspective views of the light emitting devices in the third embodiment and the fourth embodiment, respectively.

  The light-emitting device of the present invention mainly includes a light-emitting element 101, a first electrode 102 a and a second electrode 102 b that are electrically connected to the light-emitting element 101, a protection element 104, and a protection element 104. A light-transmitting material that seals the light-emitting element 101 and the protective element 104, the insulating substrate 103 including the third electrode 107 a and the fourth electrode 107 b to be connected, and the concave opening 106 on which the third electrode 107 a and the fourth electrode 107 b are mounted. It is comprised from the member and 105. That is, the present invention is characterized in that a pair of positive and negative electrodes is provided in the concave opening so that the protective element disposed in the concave opening is electrically connected in the concave opening.

(Insulating substrate 103)
In the light emitting device 100 of the present embodiment, the insulating substrate 103 is a thin rectangular parallelepiped whose plane is substantially rectangular, and a concave opening 106 that is recessed from the plane side is formed at the end. On the surface of the insulating substrate, a light reflecting surface 110 on which the light emitting element 101 is placed and a first electrode 102a and a second electrode 102b are formed so as to sandwich the light reflecting surface 110. . In addition, a third electrode 107a and a fourth electrode 107b that are electrically connected to the first electrode 102a and the second electrode 102b, respectively, are formed on the bottom surface of the concave opening 106 so as to be separated from each other. Here, in the present invention, the shape and number of the insulating substrate 103, the concave opening 106, and each electrode can be variously selected according to the purpose. Further, a heat sink may be inserted below the mounting surface of the light emitting element 101, whereby the heat accumulated in the light emitting device can be efficiently drawn to the circuit board side on which the heat sink is mounted.

  As a material for the insulating substrate 103, a resin substrate, a hybrid substrate such as a glass epoxy substrate in which an inorganic substance is contained in an organic substance, an inorganic substrate such as a ceramic substrate, or the like can be used. In particular, when high heat resistance and high weather resistance are desired, it is preferable to use a hybrid substrate or an inorganic substrate.

In the light-emitting device of the present invention, a plurality of light-emitting devices can be obtained at low cost by separately assembling a plurality of other members on the insulating substrate 103 to form an aggregate of light-emitting devices and then dividing the light-emitting device. Further, when forming a light emitting device that requires high contrast, dark-colored insulation can be achieved by including Cr ₂ O ₃ , MnO ₂ , TiO ₂ , Fe ₂ O _3, etc. in the base material of the insulating substrate itself. It is preferable to use a conductive substrate.

  The main material of the ceramic substrate is preferably alumina, aluminum nitride, mullite or the like. A ceramic substrate is obtained by adding a sintering aid to these main materials and sintering. For example, 90 to 96% by weight of the raw material powder is alumina, and 4 to 10% by weight of viscosity, talc, magnesia, calcia, silica and the like are added as sintering aids and sintered at a temperature range of 1500 to 1700 ° C. 40-60% by weight of ceramics and raw material powder is alumina, and 60-40% by weight of borosilicate glass, cordierite, forsterite, mullite, etc. are added as sintering aids and sintered at a temperature range of 800 ° C to 1200 ° C. The ceramics etc. which were made to mention are mentioned. Such a ceramic substrate can be processed into various shapes at the stage of the green sheet before firing.

(First concave opening 106)
The insulating substrate 103 of this embodiment has a first concave opening 106 that is recessed from the plane side other than the region where the light emitting element 101 is mounted. A third electrode 107 a and a fourth electrode 107 b described later are exposed on the bottom surface of the first concave opening 106. The electrode on the light emitting element mounting surface side of the protection element 104 is electrically connected to the third electrode 107 a by a wire 108. On the other hand, the bottom electrode of the protective element 104 is bonded and fixed to the fourth electrode 107b with a conductive member. Here, the method of electrically joining the protection element 104 to the third electrode 107a and the fourth electrode 107b can be variously selected depending on the type of the protection element. For example, the protection element having both electrodes on the same surface side. In the case of an element, it may be flip-chip mounted without using a wire, or mounted so that both electrodes are on the plane side, and each electrode is connected to the third electrode and the fourth electrode by a wire. Also good.

The first concave opening 106 is formed in a substantially rectangular shape in plan view. However, the first concave opening 106 is not limited to this, and the inside of the first concave opening 106, preferably the first concave opening 106. It is only necessary that the protective element 104 can be placed on the bottom surface and the third electrode 107a and the fourth electrode 107b that are electrically connected to the protective element are exposed. A plan view of the first concave opening 106 may be a circle, an ellipse, a triangle, a quadrangle, or a shape that approximates these. In addition, the size, depth, and the like can be appropriately adjusted depending on the number of protection elements 104 to be mounted, a bonding method, and the like.
The concave opening of this embodiment is an anchor for fixing the translucent member to the insulating substrate by extending a part of the translucent member in the concave opening as well as for accommodating the protective element. Can also be used. Accordingly, the light-emitting device of this embodiment can be a light-emitting device with excellent reliability without the light-transmitting member being peeled from the insulating substrate. Note that the bottom surface or the side surface of the concave opening of this embodiment is preferably embossed or plasma treated. This is because such a surface treatment increases the adhesion area of the bottom surface or the side surface of the concave opening, thereby improving the adhesion with a translucent member described later.

(Second concave opening 210)
Further, as shown in FIG. 3, a second concave opening may be provided in addition to the first concave opening in the plane of the insulating substrate 103. Since the anchor effect is obtained by arranging a part of the translucent member in such a concave opening portion, the adhesion between the insulating substrate 103 and the translucent sealing member 105 is improved. be able to. It is preferable that the first concave opening and the second concave opening have substantially the same shape from the viewpoint of causing the adhesive force between the insulating substrate 103 and the translucent sealing member 105 to work equally in each direction. Further, from the same point of view, the light emitting element is disposed between the first concave opening and the second concave opening, and each member including electrodes and wires has a substantially symmetrical arrangement pattern around the light emitting element. It is preferable. Similar to the first concave opening 106, a protective element and other types of semiconductor elements can be mounted in the second concave opening 210. At that time, a pair of positive and negative electrodes can be provided in the second concave opening 210 so as to make electrical connection with the element in the concave opening.
(External connection electrodes 109a and 109b)
The external connection electrodes 109a and 109b provided on the back surface of the insulating substrate can be electrodes connected to the conductor wiring of the mounting substrate by soldering. Further, since the external connection electrodes 109a and 109b also serve as a heat dissipation path from the light emitting device to the mounting substrate, the portions above the external connection electrodes 109a and 109b are the regions most affected by the temperature change, Peeling easily occurs at the adhesive interface between the translucent member and the insulating substrate having different expansion coefficients. Therefore, the first concave opening and the second concave opening are respectively opposed to a pair of external connection electrodes 109a and external connection electrodes 109b provided on the bottom surface side of the insulating substrate. preferable. That is, it is preferable that a concave opening is also provided at the end on the same side as the end of the insulating substrate provided with the external connection electrodes. Thereby, the adhesion and reliability between the insulating substrate 103 and the translucent member 105 in the upper part of the external connection electrodes 109a and 109b, which are the regions most affected by the thermal cycle, can be enhanced. Here, the second concave opening 210 may or may not be equipped with a protective element, and may have any shape, size, and depth similar to the first concave opening 106. . Further, like the first concave opening 106, it is preferable that a process or the like for increasing the bonding area is performed.

(Protective element 104)
There may be one protective element 104, or two or more. Here, the protective element 104 is not particularly limited, and may be any known element mounted on the light emitting device. For example, overheating, overvoltage, overcurrent, a protection circuit, an electrostatic protection element, and the like can be given. Specifically, a Zener diode, a transistor diode, or the like can be used.

(Electrodes 102a, 102b, 107a, 107b, 109a, 109b)
The light emitting device of the present invention has at least a cathode electrode and an anode electrode that are electrically connected from the plane side to the bottom side of the insulating substrate, and a part of them is a plane of the insulating substrate, the first concave shape. It is exposed from the bottom surface of the opening and the bottom surface of the insulating substrate. These shapes are not particularly limited, and can be appropriately changed depending on the number, type, and size of the light-emitting element 101 and the protection element 104 to be mounted, the wiring shape of the circuit board, and the like.

  The material of the electrodes 102a, 102b, 107a, 107b, 109a, and 109b is not particularly limited as long as it has conductivity, and preferably has high thermal conductivity. Examples of such a material include tungsten, chromium, titanium, cobalt, molybdenum, and alloys thereof.

  The first electrode 102a, the second electrode 102b, the third electrode 107a, and the fourth electrode 107b are preferably covered with a light-transmitting member 105, which will be described later. Therefore, a decrease in reliability of the light emitting device can be suppressed. On the other hand, since the external connection electrodes 109a and 109b are exposed on the surface, the external connection electrodes 109a and 109b are preferably made of an antioxidant metal such as gold or stainless steel, and the antioxidant film made of such a material has a surface. Even if it is formed, the same effect can be obtained.

  In addition, it is preferable that at least the outermost surfaces of the first electrode 102a and the second electrode 102b are formed of a member having a high reflectance with respect to light from the mounted light emitting element 101. Specific examples of the material include high light reflective metals such as chromium, silver, and aluminum. Thereby, the light extraction efficiency of the light emitting device can be increased. The same effect can also be obtained by finishing the surfaces of the first electrode 102a and the second electrode 102b in a mirror state by silver or white surface treatment or the like.

(Light emitting element 101)
The light emitting element is usually a semiconductor light emitting element, and any element may be used as long as it is an element called a so-called light emitting diode. For example, a stacked structure including an active 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. 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. Alternatively, the semiconductor active layer may have a single quantum well structure or a multiple quantum well structure in which a thin film in which a quantum effect is generated is formed. The active layer may be doped with donor impurities such as Si and Ge or acceptor impurities such as Zn and Mg. The emission wavelength of the resulting 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 active layer, the type of impurities doped in the active layer, etc. .

  The light emitting element 101 is fixed on the plane of the insulating substrate 103 by a bonding member. The light-emitting element 101 may be directly mounted on the plane of the insulating substrate 103, but may be mounted via a heat sink, mounted on the plane of the first electrode 102a or the second electrode 102b, The light reflecting surface 110 may be formed at the interface with the insulating substrate 103, whereby the heat dissipation and light extraction efficiency of the light emitting device can be improved. In the case of a light-emitting element having both electrodes on the same surface side, flip-chip mounting can be performed via the first electrode and the second electrode and a conductive member, whereby the light-emitting device can be formed thin.

  For example, in the case of a light emitting element having a blue or green emission color and formed by growing a nitride semiconductor on a sapphire substrate, the bonding member may be an epoxy resin, silicone, or the like. In consideration of improvement in light extraction from the light emitting element, aluminum, silver, or rhodium having high light reflectance can be disposed on the back surface of the light emitting element by a forming method such as plating or sputtering. Further, in consideration of deterioration due to light and heat from the light emitting element 101, a eutectic material containing Au and Sn, a brazing material such as a low melting point metal, a conductive paste, or the like may be used as a bonding material. Further, in the case of a light emitting element made of GaAs or the like and having electrodes formed on both surfaces thereof, such as a light emitting element having red light emission, or when a light emitting element having both electrodes on the same surface is flip-chip mounted, the first electrode It can be fixed on the plane of 102a or the second electrode 102b by a conductive paste such as silver, gold or palladium, a metal bump, or a eutectic material such as Au-Sn.

  In the light emitting device of the present invention, the number of light emitting elements mounted on one insulating substrate may be one or plural. In this case, in order to improve luminous intensity, a plurality of light emitting elements that emit light of the same emission color may be combined. In addition, for example, in a light-emitting device that supports full-color display, color reproducibility can be improved by variously combining a plurality of light-emitting elements having different emission colors. In the case of using a plurality of light-emitting elements, it is preferable to form the first electrode 302a and the second electrode 302b for each light-emitting element as in the light-emitting device in FIG. It is ensured and the temperature rise of the light emitting device caused by mounting a plurality of light emitting elements can be suppressed.

(Translucent member 105)
In the present embodiment, the translucent member 105 seals the light-emitting element 101 and the protection element 104, and protects them from the external environment such as external force and moisture. Further, the light from the light emitting element 101 is also efficiently emitted to the outside. As such a specific material constituting the translucent member 105, transparent resin or glass having excellent weather resistance such as epoxy resin, urea resin, silicone, modified epoxy resin, modified silicone resin, and polyamide is preferably used. Used. In the case where the light emitting elements 101 are arranged at a high density, it is more preferable to use an epoxy resin, a silicone resin, or a combination thereof in order to suppress the joint breakage between the members due to thermal shock. Further, the light transmissive member 105 may contain a diffusing agent in order to further increase the viewing angle. As a specific diffusing agent, barium titanate, titanium oxide, aluminum oxide, silicon oxide or the like is preferably used. Moreover, an organic or inorganic coloring dye or coloring pigment can be contained for the purpose of cutting an undesired wavelength.
Further, as shown in FIG. 7, in the light emitting device of this embodiment, a wavelength conversion member 410 such as a fluorescent material that converts the wavelength of at least a part of the light from the light emitting element 101 is provided on a part of the light transmitting member 305. It can also be included. The wavelength conversion member 410 is integrally formed simultaneously with the formation of the translucent member 305, or can be formed prior to the formation of the translucent member 305 by a known molding technique such as screen printing or stencil printing. .

  The shape of the translucent member 105 is not particularly limited as long as it covers the light emitting element 101 and the protection element 104, and can be variously changed depending on the purpose. For example, as in the light emitting device of FIG. 6, when it is desired to give directivity to light emission of the light emitting device or to diffuse light from the light emitting element, it has a convex portion designed to obtain desired light. Although a translucent member is used, it is preferable to provide a flat portion extending to the side of the convex portion. This facilitates handling of the light emitting device. In addition, it is easy to confirm the lateral displacement of the translucent member, and by controlling the displacement range within the size of the flat portion, it is possible to manufacture with high productivity.

When the fluorescent material is contained in the translucent member 105, the translucent member 105 is excellent in heat resistance and light resistance, and is not easily deteriorated in color even when exposed to short wavelength high energy light including ultraviolet rays. It is preferably a silicone resin, which suppresses the occurrence of color misregistration and color unevenness. The fluorescent material that can be used in this embodiment is one that converts light from the light emitting element 101, and one that converts light from the light emitting element 101 to a longer wavelength is more efficient. When the light from the light emitting element is high energy short wavelength visible light, a YAG: Ce phosphor or a Ca ₂ Si ₅ N ₈ phosphor, which is a kind of aluminum oxide phosphor, is preferably used. In particular, the YAG: Ce phosphor absorbs part of the blue light from the LED chip depending on its content and emits yellow light that is a complementary color. Can be formed relatively easily.
As shown in FIG. 6 or FIG. 7, the translucent member 305 in the light emitting device of this embodiment has a convex portion 305a and a flat portion 305b. The flat portion 305 b of the translucent member 305 is a thin portion that is extended on the upper surfaces of both end portions of the insulating substrate 103. Further, the convex portion 305a of the translucent member 305 is a thick portion protruding from the upper surface of the flat portion 305b. For example, a lens shape such as a bowl shape is used to optically control light emitted from the light emitting device May have. And the translucent member 305 of this form has the boundary line 305c from which the member thickness differs between the said flat part 305b and the convex part 305a. The boundary line 305c between the convex part 305a and the flat part 305b of the translucent member 305 is disposed on the first concave opening part 106 or the second concave opening part 210, and further, the boundary line 305c. It is preferable that a part of the translucent member 305 including the upper surface of the insulating substrate 103 is extended from the upper surface of the insulating substrate 103 to the first concave opening 106 or the second concave opening 210. “The boundary line between the convex portion and the flat portion of the translucent member is disposed on the concave opening” means that the convex portion and the flat portion of the translucent member are viewed in plan view of the insulating substrate. This means that the translucent member is arranged so that the boundary line with the crossing at least a part of the opening shape of the concave opening.
The light emitting devices in the third and fourth embodiments of the present invention will be described in detail below. First, from the viewpoint of ensuring the adhesion between the translucent member and the insulating substrate, it is preferable that the translucent member disposed inside or above the concave opening is as thick as possible. That is, it is preferable to secure the adhesiveness of the entire translucent member to the insulating substrate by disposing the convex portion, which is a thick portion of the translucent member, on the concave opening.
However, the convex part of the translucent member is a part for optically controlling the light emitted from the light emitting device, and when the convex part is arranged on the concave opening part, the light entering the concave opening part is also emitted. Therefore, the optical characteristics of the light emitting device may be affected.
On the other hand, if the part disposed in the concave opening is only a flat part that is thinner than the convex part, the connection strength between the convex part and the flat part of the translucent member cannot be maintained, and the entire translucent member There is a risk that the adhesion of the insulating substrate cannot be ensured.
Therefore, in the light emitting devices according to the third and fourth embodiments of the present invention, the connection portion (the portion including the boundary line 305c on the upper surface) located between the convex portion and the flat portion of the translucent member is a concave opening. It is what was arranged. That is, the end of the convex portion that does not relatively affect the optical characteristics is disposed in the concave opening, and the end of the convex portion and the end of the flat portion are part of the translucent member that extends into the concave opening. Connect with. Thus, the thickness of the connection part of the convex part of a translucent member and a flat part is earned by utilizing the shape of a concave opening part skillfully. Accordingly, it is possible to ensure adhesion between the translucent member and the insulating substrate while maintaining good optical characteristics of the light emitting device, and prevent the translucent member from being peeled off from the insulating substrate. .

(Wavelength conversion member 410)
Further, as shown in FIG. 7, a wavelength conversion member 410 may be separately provided between the translucent member 105 and the light emitting element 101. In this case, the wavelength conversion member 410 covers only the periphery of the light emitting element 101 so as not to cover the protection element 104, and further, the convex portion is formed so that the shape of the translucent member 105 thereabove covers the wavelength conversion member 104. It is preferable to have. It is preferable that the topmost portion of the convex portion is located on the wavelength conversion member 104. Thereby, the light-emitting device which can extract efficiently the light emitted from the side of the wavelength conversion member 104 is obtained. Furthermore, when the wavelength conversion member 104 is sealed with a translucent member having a convex part and a flat part extending to the side of the convex part, the thickness of the flat part is the thickness of the wavelength conversion member. Thinner is preferred. Thereby, the light emitted from the side of the wavelength conversion member 104 can be efficiently extracted with less light loss due to the flat portion of the translucent member.

(Wire 108)
In the present invention, the means for electrically connecting the light-emitting element 101 and the protective element 104 to the electrodes 102a, 102b, 107a, and 107b is not particularly limited. However, when wires are used, they are connected to the electrodes of the light-emitting element 101 and the protective element 104. It is preferable that the ohmic property is good, the mechanical connectivity is good, or the electrical conductivity and thermal conductivity are good. The thermal conductivity, preferably ^{0.01cal / S · cm 2 · ℃} / than about cm further ^{0.5cal / S · cm 2 · ℃} / cm or higher order is more preferable. Considering workability and the like, the diameter of the wire is preferably about 10 μm to 45 μm. Examples of such wires include metals such as gold, copper, platinum, and aluminum, and alloys thereof. The wire can be easily connected to the light emitting element, the metal member for wire bonding, and the wire bonding apparatus.

  When the wire 108 is used as the electrical joining means of the protective element 104, the wire 108 is preferably accommodated in the concave opening 106. Thereby, a more reliable light-emitting device with reduced wire breakage can be obtained.

The insulating substrate 103 is deformed in the arrangement direction of the external connection electrodes 109a and 109b due to the influence of the thermal cycle of the external connection electrodes 109a and 109b. Therefore, the external connection electrode 109a that is most susceptible to the thermal cycle. , 109b, the tensioning direction of the wire 108 of the protection element 104 is preferably substantially perpendicular to the arrangement direction of the external connection electrodes 109a, 109b. Further, even when a wire is used as the conduction means of the light emitting element 101, it is preferable that the direction in which the light emitting element 101 is stretched is substantially perpendicular to the direction in which the external connection electrodes 109a and 109b are arranged.
The translucent member of this embodiment can be formed by various molding methods such as transfer molding, line coating, stencil printing, or screen printing. In such a forming method, the material of the translucent member is arranged by being continuously supplied in a predetermined direction on the insulating substrate. At this time, the direction of supply and arrangement of the material of the translucent member is substantially the same as the tension direction of the wire connected to the light emitting element or the protection element, so that the material of the translucent member supplied is a wire. Since the impact on the wire can be reduced, the metal fatigue of the wire can be reduced. Further, when the insulating substrate is seen in plan view, the tension direction of the wire connected to the light emitting element or the protective element is the central axis in the longitudinal direction in the opening shape of the first concave opening or the second concave opening. It is preferable that the directions are substantially the same. Thereby, not only the impact on the wire can be reduced, but also the material continuously supplied in the wire tension direction can be smoothly filled into the concave opening without staying around the wire. Therefore, the impact exerted on the wire by the material of the translucent member can be moderated relatively, and a more reliable light-emitting device can be obtained. Here, the direction in which the longitudinal central axis in the opening shape of the concave opening portion is substantially the same as the direction in which the conductive wire is stretched is not limited to the case where both directions are parallel, but also allows a difference of about ± 10 ° in both directions. It shall be included as a range.

  It can be used for illumination light sources, various indicator light sources, in-vehicle light sources, display light sources, liquid crystal backlight light sources, and the like.

FIG. 1 is a schematic perspective view showing a light emitting device according to an embodiment of the present invention. FIG. 2 is a schematic plan view of the light emitting device of FIG. FIG. 3 is a schematic perspective view showing a light emitting device according to another embodiment of the present invention. FIG. 4 is a schematic cross-sectional view taken along line AA of the light emitting device of FIG. FIG. 5 is a schematic bottom view of the light emitting device of FIG. FIG. 6 is a schematic perspective view showing a light emitting device according to another embodiment of the present invention. FIG. 7 is a schematic perspective view showing a light emitting device according to another embodiment of the present invention. FIG. 8 is a schematic cross-sectional view showing a conventional light emitting device. FIG. 9 is a schematic cross-sectional view showing another conventional light emitting device.

Explanation of symbols

100, 200, 300, 400 ... light emitting devices 101, 301, 801 ... light emitting elements 102a, 302a, 802a ... first electrodes 102b, 302b, 802b ... second electrodes 103, 803,. .... Insulating substrates 104, 804 ... Protection elements 105, 305, 805 ... Translucent member 305a ... Convex part 305b of translucent member ... Flat part 305c of translucent member ... The boundary lines 106, 906 of the translucent member and the flat portion of the translucent member, the first concave opening 107a, the third electrode 107b, the fourth electrode 108, and the wires 109a, 109b. , 809a, 809b ... External connection electrode 110 ... Light reflecting surface 210 ... Second concave opening 410 ... Wavelength conversion member

Claims (10)

An insulating substrate provided with a first electrode and a second electrode on a plane; a light-emitting element mounted on the plane and electrically connected to the first electrode and the second electrode; A light-emitting device comprising: a protective element placed in a first concave opening recessed from the plane side; and the light-emitting element and a translucent member that seals the protective element,
The first concave opening has a third electrode and a fourth electrode electrically connected to the first electrode and the second electrode, respectively, on the bottom surface thereof,
The light-emitting device, wherein the protective element is electrically connected to the third electrode and the fourth electrode.   The protection element is electrically connected to at least one of the third electrode and the fourth electrode by a wire, and the wire is accommodated in the first concave opening. The light-emitting device of description.   The insulating substrate has a second concave opening having substantially the same shape as the first concave opening on the plane side, and the first concave opening and the second concave opening are respectively The light-emitting device according to claim 1, wherein the light-emitting device faces a pair of external connection electrodes provided on a bottom surface side of the insulating substrate.   The light emitting device according to claim 3, wherein an arrangement direction of the external connection electrodes is substantially perpendicular to a tension direction of the wires.   The translucent member includes a convex portion disposed on the light emitting element and a flat portion extending on the insulating substrate at a side of the convex portion. 5. The light emitting device according to any one of items 1 to 4.   The light emitting element is covered with a wavelength conversion member that absorbs at least part of the light from the light emitting element and converts it into other light, and the convex of the translucent member is covered so as to cover the wavelength conversion member. The light emitting device according to claim 5, further comprising a portion.   The light emitting device according to claim 5, wherein a thickness of the flat portion is thinner than a thickness of the wavelength conversion member.   The convex part of the translucent member is a thick part protruding from the upper surface of the flat part, and the boundary line between the convex part and the flat part is the first concave opening or the second part. 6. The light emitting device according to claim 5, wherein a part of the translucent member disposed on the concave opening and including the boundary line is extended into the first concave opening or the second concave opening. apparatus.   The light emitting device according to any one of claims 3 to 8, wherein the light emitting element is disposed between the first concave opening and the second concave opening.   When the insulating substrate is viewed in plan, the tension direction of the wire connected to the light emitting element or the protection element is substantially the same as the central axis in the longitudinal direction of the first concave opening or the second concave opening. The light-emitting device according to claim 2, wherein the light-emitting device has a direction.

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