JP5256591B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device, and more particularly to a light emitting device provided with a protection element.

  2. Description of the Related Art In recent years, with respect to light emitting devices that use semiconductors, higher output and improved reliability have become issues as the application spreads. Even in so-called lamp-type light emitting devices, demands for resistance to static electricity, overvoltage, overcurrent, reverse voltage, etc. are increasing for light emitting devices that require high reliability and high output, such as traffic lights, in-vehicle components, and channel letters for signboards. ing.

  In order to increase the resistance of the light emitting device to abnormal current and abnormal voltage, a method of providing a protective element such as a Zener diode in the package together with the light emitting element is generally used. A lamp type light emitting device includes a light emitting element in a package, and lead terminals are integrally formed as positive and negative electrodes to which positive and negative electrodes of the light emitting element are connected, respectively. As described above, when providing a protective element in a light-emitting device with limited space, there are many restrictions in terms of optical characteristics such as light distribution and the manufacturing process, but there is a recess in one lead terminal and light is emitted from the bottom of the recess. A light-emitting device in which a protective element is placed on a flange that surrounds the recess, and a light-emitting device in which a protective element is placed on a lead terminal that is paired with a lead terminal on which the light-emitting element is placed It has been proposed (for example, Patent Document 1).

Such a configuration has less adverse effect on the light distribution due to the installation of the protective element, and the manufacturing process is easy.
JP-A-10-256610

In the light emitting device, due to the heat generation of the light emitting element, due to thermal expansion, the adhesion between the metal member and the other members constituting the light emitting device is reduced, the package is cracked, or the wire is broken As a result, problems such as affecting the reliability of the light emitting device may occur.
However, Patent Document 1 does not mention the influence of the shapes and positions of leads, collars, and the like on other components of the light emitting device such as a package.
The present invention has been made in view of the above problems, and by using a protective element in combination with a light-emitting element, it can prevent cracks and lowering of adhesion between constituent members and disconnection of wires while securing a higher pressure resistance. Thus, it is an object to provide a highly reliable light-emitting device with improved characteristics.

A light emitting element; a protective element; a first and second metal member electrically connected to the light emitting element and the protective element; and a package in which at least part of the first and second metal members is embedded. A light emitting device,
The first metal member has a recess for placing the light emitting element and a flange that surrounds the recess, and the recess and the flange are opposed to the second metal member, and the flange A region formed with a constant width from the outer periphery of the recess between a side facing the second metal member and a side opposite to the facing side of the second metal member, and the second metal member A region that gradually becomes wider than the constant width as it approaches the second metal member on the side opposite to the second metal member, and a region that is narrower than the region that becomes wider on the side opposite to the opposite side of the second metal member. And a region .

  In this light emitting device, it is preferable that the protective element is placed on the flange portion of the first metal member, and further, the protective element is placed on the wide region of the flange portion of the first metal member. Is preferred.

Moreover, it is preferable that the recessed part and collar part of a 1st metal member are formed in line symmetry in planar view.
Further, the second metal member gradually increases in width toward the first metal member in a part of the region facing the first metal member, and the second metal member is line symmetric in plan view. It is preferable that the protective element is placed in the wide region.

In this light-emitting device, it is preferable that the wide region in the second metal member is a region that gradually becomes wider.
In these light-emitting devices described above, it is preferable that a light-transmitting coating material is embedded at least in the recess, and the light-transmitting coating material preferably contains a fluorescent substance. It is preferable that a lens is further provided in the light emitting direction of the light emitting element.

It is preferable that the symmetrical center line in the plan view of the second metal member is arranged on the extended line of the symmetrical center line in the plan view of the first metal member.
In these light-emitting devices described above, it is preferable that a light-transmitting coating material is embedded at least in the recess, and the light-transmitting coating material preferably contains a fluorescent substance. It is preferable that a lens is further provided in the light emitting direction of the light emitting element.

  According to the present invention, the pressure resistance can be further ensured by using the protective element in combination with the light emitting element. Further, the first metal member has a concave portion and a flange portion on which the light emitting element is placed, the concave portion and the flange portion are opposed to the second metal member, and the flange portion is the second portion. By gradually increasing the width toward the second metal member on the side facing the metal member, an area for placing the protection element is appropriately secured while minimizing the influence on reliability. be able to.

According to another light emitting device of the present invention, the first metal member has a recess facing the second metal member and mounting the light emitting element, and a flange surrounding the recess, The metal member of 2 is wide toward the first metal member in a part of the region facing the first metal member, so that a region for placing the protection element is secured, and the package and Adhesion with the second metal member can be improved. Furthermore, since the wire length can be shortened by using the first metal member and the wide portion adjacent to the collar portion for mounting the protective element or wire bonding, preventing the wire from being disconnected. Can do.
Therefore, the characteristics of the light emitting device itself can be improved, and the life can be extended.

The light emitting device of the present invention mainly includes a light emitting element, a protective element, first and second metal members electrically connected to the light emitting element and the protective element, and a package.
(Light emitting element)
The light emitting element may be a semiconductor light emitting element, and any element may be used as long as it is an element called a light emitting diode. For example, a laminated structure including an active layer is formed on a substrate by various semiconductors such as a nitride semiconductor such as InN, AlN, GaN, InGaN, AlGaN, InGaAlN, a III-V compound semiconductor, and a II-VI compound semiconductor. 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 one of C-plane, A-plane and R-plane, silicon carbide (6H, 4H, 3C), silicon, ZnS ZnO, GaAs, diamond; oxide substrates such as lithium niobate and neodymium gallate, nitride semiconductor substrates (GaN, AlN, etc.), and the like. 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 and / 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. .

Such a light emitting element is mounted on a metal member to be described later. In order to place the light emitting element on the metal member, a joining member is used. For example, in the case of a light emitting element having blue and green light emission and having a nitride semiconductor grown on a sapphire 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 may be plated with Al, without using resin, solder such as Au—Sn eutectic, low melting point metal, etc. A material may 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 that emits red light, die bonding may be performed using a conductive paste such as silver, gold, or palladium.
In the light emitting device of the present invention, only one light emitting element may be mounted, but two or more light emitting elements may be mounted.

(First and second metal members)
The metal member is usually electrically connected to the light emitting element, the protective element, and the like, and generally functions as a lead electrode and / or a function of placing the light emitting element, the protective element, and the like. Since a part of the metal member is normally embedded in the package, the part that functions as a mounting table such as a light emitting element and / or a lead electrode in the package is extended to the internal terminal and the package, A portion having a function of establishing electrical connection with an external terminal is also referred to as an external terminal. Accordingly, the material is not particularly limited as long as it can perform these functions, but it is preferably formed of a material having a relatively large thermal conductivity. By forming with such a material, heat generated in the light emitting element can be efficiently released. For example, a material having a thermal conductivity of about 200 W / (m · K) or more, a material having a relatively large mechanical strength, or a material that can be easily punched or etched is preferable. For example, metal such as copper, aluminum, gold, silver, tungsten, iron, nickel or iron-nickel alloy, phosphor bronze, iron-containing copper, etc. or a metal plating film such as silver, aluminum, copper, gold, etc. is applied to the surface. Examples include rubbed ones. The surface of the metal member is preferably smooth in order to improve the reflectance. The metal member is usually formed with a uniform film thickness, but may be partially thick or thin.

  The shape of the metal member is not particularly limited, and can be appropriately determined in consideration of the number of light emitting elements, the arrangement, the space in which the light emitting elements can be arranged, and the like. For example, the first metal member on which the light emitting element is placed as an internal terminal has a recess for placing the light emitting element and a flange that surrounds the recess. It is suitable that the recess and the collar face the second metal member, and that the collar gradually becomes wider as it approaches the second metal member on the side facing the second metal member. Yes. Here, the side facing the second metal member of the buttocks is not only the portion that strictly faces the first metal member, but, for example, the buttocks that surround the second metal member side half of the recess Specifically, it refers to the second metal member side of broken line BB ′ in FIG. By having such a shape, it is possible to effectively prevent cracking of the package while appropriately securing a region on which the protective element is placed. In addition, it is possible to effectively prevent the resin dripping from the concave portion and the collar portion of the translucent coating material embedded in the concave portion described later.

  Moreover, as for the 1st metal member, it is preferable that the recessed part and the collar part are formed in the shape of line symmetry in planar view (refer Fig.2 (a)). Thereby, the thermal stress resulting from the thermal expansion of the first metal member due to the heat generation of the light emitting element can be evenly distributed without being unevenly distributed, cracks generated in the package can be prevented, and the material such as the package can be prevented. Decrease in adhesion can be prevented and peeling and the like can be effectively prevented. In addition, the size and shape of the metal member constituting the internal terminal enhances heat dissipation, effectively suppresses the temperature rise of the arranged light emitting element, and can supply more current to the light emitting element. It is preferable to adjust so that the workability of wire bonding can be facilitated.

  The concave portion only needs to have at least a bottom area on which the light emitting element can be placed. For example, the concave portion may have a circular shape, an elliptical shape, a polygonal shape with rounded corners, or a shape deformed based on these shapes. it can. The depth may be, for example, not less than the height of the light emitting element, and more than about 100 μm, and about 0.5 mm or less is suitable. The side surface may be vertical, but is preferably inclined so as to become narrower toward the bottom surface. For example, it is suitable to incline at about 0 to 45 ° or about 20 to 40 ° in the normal direction with respect to the bottom surface. Thereby, the light from a light emitting element can be efficiently guide | induced to an upper surface.

  The collar portion surrounds the outer periphery of the recess and is disposed at a height different from the bottom surface of the recess. In addition, it is preferable that the surface is rounded from a recessed part to a collar part (refer X in FIG.2 (b)). By rounding in this way, the light-transmitting covering member and the package on the edge of the opening of the recess are less likely to crack, and the light-transmitting covering material and the package can be prevented from peeling off. Corresponding to the shape of the recess, the collar portion is usually a round shape, an elliptical shape having a diameter of about 2 to 5 mm, a shape with rounded corners of a polygonal shape, or a shape deformed based on these shapes. The width includes a region formed with a constant width of about 0.3 to 1.5 mm, for example, from the outer periphery of the recess. That is, it is suitable that the collar portion formed in the region having the constant width is substantially similar to or substantially similar to the outer peripheral shape of the recess. Moreover, the collar part has the area | region which becomes wide gradually as it approaches the 2nd metal member in addition to the area | region of a fixed width | variety. Here, gradually widening does not mean that the wide portion (protruding portion) is formed by an abrupt change, for example, within 0.3 mm, within 0.25 mm, or even 0 per 1 mm of the outer periphery of the collar. .Increase or decrease in width within 2 mm. Thus, the surface tension of the translucent coating material is appropriately adjusted when the translucent coating material is coated, for example, by potting, from the light emitting element in the recess to the eaves portion by gradually changing the eaves portion. Working and can properly coat the desired site. This is because when a protruding part is formed in the collar part with a sharp change, the translucent coating material flows out from both sides (corner part) of the protruding part, and the surface tension can work well. This is to avoid the phenomenon of disappearing.

  In addition, the outer periphery of the flange portion and the wide portion is rounded in the vicinity facing the second metal member (for example, in the vicinity of 13c in FIG. 2A). The crack of the package between the metal members can be effectively prevented.

  The position of the wide region of the buttocks is not particularly limited, but usually, wire bonding is performed from the light emitting element placed in the recess to the second metal member, and from the protective element to the second element. Since wire bonding is also performed over the metal member, it is preferable to determine so as not to hinder or hinder these wire bonding. Usually, the recessed part and the collar part in which a light emitting element is mounted are arrange | positioned so as to oppose the 2nd metal member. Therefore, it is preferable that the wide area | region of a collar part is arrange | positioned on the side facing a 2nd metal member, and is biased from the symmetrical centerline mentioned later of a 1st metal member. Further, the widened region is preferably arranged only on the side facing the second metal member (for example, on the second metal member side of the line BB ′ in FIG. 2A). It is preferable that a wide region is not disposed on the external terminal side of the metal member. If there is a wide area on the external terminal side of the first metal member, on the external terminal side of the first metal member, the joint between the external terminal and the collar part, that is, the curved part from the external terminal to the collar part This is because the shape changes abruptly (the width changes abruptly), and cracks are likely to occur in the package around the periphery, particularly the curved portion.

  This wide area is suitable as an area for placing the protection element. In particular, the wide region is disposed offset from the symmetry center line of the first metal member, and the protective element is placed on the wide region, so that a sufficient placement region for the protective element can be secured. Since the distance between the first metal member and the second metal member can be made larger than the shortest distance on the symmetry center line of the one metal member, it is not too close to the light emitting element, and a sufficient distance is provided. Can be taken and does not adversely affect the light extraction. In addition, since the wide region of the collar portion is closer to the second metal member than the other regions of the collar portion, when the wire from the second metal member is bonded to the wide region, the light emitting element Therefore, the wire length can be shortened and wire breakage can be effectively prevented as compared with bonding to other regions of the buttock.

  Since the second metal member is not necessarily mounted with a light emitting element or the like, the region corresponding to the concave portion and the collar portion may not be formed. However, the second metal member is the first metal member. You may have the area | region which becomes wide toward the 1st metal member in a part of area | region which opposes a member. Thereby, the area | region for mounting a protection element on the 2nd metal member is securable. Since the widened region is closer to the first metal member than the second metal member, when the light emitting element or the wire of the protective element is bonded to the widened region, the second metal member Compared to bonding, the length of the wire can be shortened, and wire breakage can be effectively prevented. The widened region may have a shape protruding toward the first metal member, but is preferably a gradually widened region. Here, the width gradually increases as described above.

  Furthermore, the second metal member (preferably with respect to an extension line of the symmetrical center line in the plan view of the first metal member) is preferably formed in line symmetry in the plan view. Thereby, the uneven distribution of the stress caused by the thermal expansion of the metal member in the package of the light emitting device can be made more uniform, and cracks and packages can be further prevented from being peeled off. That is, uneven distribution of stress and twisting of the lead are less likely to occur, and cracks in the package and wire breakage can be effectively prevented.

  Moreover, it is preferable that a protective element is placed in this wide region. Thereby, the optimal distance between the first metal member and the protection element can be secured, the electrical connection can be further stabilized, and the influence on the light distribution can be minimized. . Moreover, since the wide area | region is arrange | positioned facing the 1st metal member, the length of the wire bonded to a 1st metal member can be shortened, and wire breakage can be prevented effectively.

  Furthermore, it is preferable that the second metal member has a hole formed in a partial region thereof (see FIG. 2A). Thereby, a contact area with a package etc. can be increased and adhesiveness can be improved. In addition to forming the hole, the wide area as described above is formed in the portion of the second metal member disposed in the package, thereby increasing the contact area and complicatedly relating to the package. Therefore, the adhesion can be further improved. Especially, this effect can be exhibited more by making a wide area | region into a more complicated shape as shown in FIG.4 (b).

  In the light emitting device, both the wide region in the first metal member and the wide region in the second metal member may be present at the same time, as long as there is a wide region in one of them. Good. Thereby, the area | region which mounts a protection element etc. or the area | region which wire-bonds can be ensured in an appropriate position. If both are present at the same time, the widened region of the collar and the widened portion of the second metal member are very close to each other, so that the protective element is mounted on the widened region and the widened portion. When placing or bonding wires, the length of the wire can be made shorter than usual, and wire breakage can be prevented more effectively.

  It is preferable that a 1st metal member is a shape extended in a direction different from those from a recessed part and a collar part as an external terminal. Moreover, it is preferable that a 2nd metal member is a shape extended in a predetermined direction as an external terminal. The extending direction of the metal member is not particularly limited, and can be appropriately adjusted in consideration of the mounting type (for example, a through-hold type, a snap mounting type, etc.). These metal members do not necessarily have to be protruded to the outside from the same surface of the package, and may be protruded to the outside from a plurality of different surfaces, or all the metal members may be protruded in the back direction of the light emitting device. Alternatively, any (preferably similar) light-emitting device of the surface-mounting type may be used by bending toward the back direction or the side direction.

  The metal member only needs to include at least two of the first and second light emitting devices described above in one light emitting device. However, the number of light emitting elements mounted on the metal member is +1 or more, or the light emitting elements mounted on the metal member. You may have more than twice this number. For example, when only one light emitting element is mounted, the light emitting element is placed on one of the metal members, and is electrically connected to one electrode of the light emitting element, and the other metal member is the light emitting element. An electrical connection with another electrode can be made.

  When two or more light-emitting elements are mounted, all or several of the light-emitting elements are placed on one metal member for electrical connection, and another metal member corresponds to each light-emitting element. Different electrical connections may be made. Further, each light emitting element is mounted on a separate metal member, and electrical connection is made. Further, another metal member is configured to take another electrical connection corresponding to each light emitting element. Also good. In this way, a plurality of light emitting elements are mounted, and for each of them, independent wiring that is electrically connected to a metal member independently, various wirings such as series or parallel on the mounting surface of the light emitting device. It is possible to select a pattern and design a free circuit. In addition, in the case of the independent wiring, it is easy to adjust the light emission intensity of the light emitting element to be mounted, which is particularly advantageous when using a plurality of light emitting elements having different light emission colors such as full color LEDs. . In addition, since the heat dissipation paths of the light emitting elements can be formed without overlapping, the heat generated from the light emitting elements can be evenly dissipated, and the heat dissipation becomes better.

  The metal member may not be electrically connected to the light-emitting element, and may be provided with only the light-emitting element placed or the light-emitting element not placed. Such a metal member can function as a heat dissipation path for guiding heat generated from the light emitting element to the outside in the package and as a countermeasure against overvoltage.

The metal member is usually electrically connected to the light emitting element and the protection element by wire bonding using a wire. The wire preferably has good ohmic properties with the electrode of the light emitting element, good mechanical connectivity, or good electrical and thermal conductivity. 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.

(package)
As long as the package can embed a part of the above-described metal member, preferably integrally or in a lump shape, and can insulate the light emitting element, the protective element, and the metal member, It may be formed of any material. Examples thereof include polyphthalamide (PPA), polycarbonate resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), ABS resin, epoxy resin, phenol resin, acrylic resin, resin such as PBT resin, ceramic, and the like. Among these, a translucent resin is preferable. In these materials, various dyes or pigments may be mixed and used as a colorant. For _{example, Cr 2 O 3, MnO 2} , Fe 2 O 3, carbon black and the like. Note that the light-transmitting property 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 size and shape of the package are not particularly limited, and may be any shape such as a cylinder, an elliptical column, a sphere, an oval, a triangular column, a quadrangular column, a polygonal column, or a shape similar to these. The lens for may be integrally formed.
In the light-emitting device of the present invention, usually, first, a light-emitting element and a protective element are mounted on a first metal member, and then the first and second metal members are inserted into a resin casting case filled with a package member. Then, it can be integrally formed by curing.

(Translucent coating material)
In the translucent covering material, the light emitting element is placed in the recess of the first metal member, and as described above, the light emitting element or the protective element and the first and second metal members are electrically connected by a wire or the like. After being obtained, it is arbitrarily embedded in the recess of the first metal member. The translucent coating material can protect the light emitting element from external force, moisture, and the like, and can also protect the wire. In addition, since the light-transmitting coating material is embedded in the concave portion of the first metal member, deterioration of the package due to light and heat can be prevented, and high luminance can be achieved by using the light-transmitting coating member. In addition, it is possible to extract light of various color tones. The translucent coating material can protect the light emitting element from external force, moisture, and the like, and can also protect the wire. Examples of the translucent coating material include transparent resins or glass having excellent weather resistance such as epoxy resins, silicone resins, acrylic resins, urea resins, or combinations thereof. The translucent coating material may be the same as the package material, but is preferably a different material, a different composition, or the like. In particular, the transparent resin contains moisture contained in the resin by baking at 100 ° C. for 14 hours or more even when moisture is contained in the translucent coating material during the process or during storage. Can escape to the open air. Therefore, it is possible to prevent water vapor explosion and peeling of the light emitting element and the above-described package material. In addition, the translucent coating material has a small difference in thermal expansion coefficient in consideration of the adhesion between the package material and the translucent coating material when affected by the heat generated from the light emitting element or the like. It is preferable to select

The translucent coating material 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 of the package. 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 inorganic phosphors such as _3- SiO ₂ are suitably 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. In addition to these fluorescent materials, any of the known fluorescent materials described in, for example, Japanese Patent Application Laid-Open Nos. 2005-19646 and 2005-8844 can be used.

(Protective element)
The protective element is not particularly limited, and may be any known element 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 the light emitting device of the present invention, usually only one protective element is mounted, but two or more protective elements may be mounted. In addition, the protective element is preferably placed on the first metal member (metal member on which the light emitting element is placed), but may be placed on the second metal member.

(Other parts)
The light-emitting device of the present invention is a lens made of plastic or glass, for example, at the light emitting part of the light-emitting element (for example, the package part above the light-emitting element) as part of the package or attached to the package surface. Etc. may be provided. In order to efficiently extract light from the light emitting element, various components such as a reflection member, an antireflection member, and a light diffusion member may be provided.

Embodiments of the light emitting device according to the present invention will be described below in detail with reference to the drawings.
Example 1
As shown in FIG. 1, the light emitting device 10 of this embodiment is a lamp type light emitting device, and includes a light emitting element 11, a protective element 12, a first metal member 13, and a second metal member 14. A part is integrally sealed with a package 15 made of epoxy resin.

The light emitting element 11 is a light emitting element made of an n-type contact layer made of n-type GaN, an n-type clad layer made of n-type AlGaN, and a nitride semiconductor such as InN, AlN, GaN, InGaN, AlGaN, InGaAlN on a sapphire substrate. A p-type cladding layer made of p-type AlGaN or InGaN and a p-type contact layer made of p-type GaN are sequentially stacked to form an InGaN semiconductor that emits blue light having a dominant wavelength of about 470 nm. .
The die bonding of the light emitting element 11 is performed using, for example, a silver paste or an epoxy resin. Further, an electrode (not shown) formed on the light emitting element 11 and the first metal member 13 are connected by a wire made of a gold wire having a diameter of 30 μm.

As shown in FIG. 1 and FIGS. 2 (a) and 2 (b), the first and second metal members 13, 14 are
It is configured such that it is bent in the package and its end protrudes from one surface of the package 15 and functions as an external terminal. These first and second metal members 13 and 14 are formed, for example, by punching a silver-plated copper plate having a thickness of 0.4 mm using a press.

The first metal member 13 includes a line-symmetric concave portion 13a and a flange portion 13b surrounding the concave portion 13a in a plan view in FIG. The flange 13b has a width of, for example, about 0.75 mm on the side that does not face the second metal member 14 (that is, the external terminal side of the first metal member 13 along the line BB ′). It gradually changes toward the side facing the second metal member 14, and the widest region 13c has a width of about 1.25 mm. The change in this case is an increase in the width of about 0.25 mm per 1 mm of the outer periphery of the collar. The wide region 13 c is disposed on both sides of the opposing region that is the shortest distance between the first metal member 13 and the second metal member 14.
Further, the second metal member 14 is formed in line symmetry with respect to an extension of the symmetry center line of the first metal member 13 in plan view.

The first metal member 13 has a Zener diode mounted as a protective element on the collar portion.
Further, light transmission by a silicone resin containing a fluorescent material (for example, YAG: Ce) and a diffusing agent (for example, titanium oxide) extends from the recess 13a of the first metal member 13 to a part of the flange portion 13b and the wide region 13c. The covering material is embedded by potting.
In addition, a lens 18 for condensing light from the light emitting element 11 is provided at the center of the upper surface of the package 15 and above the recess 13a.

  According to the light emitting device having such a configuration, since the protective element is provided, the electrostatic withstand voltage strength can be further ensured. Further, since the concave portion and the flange portion of the first metal member are formed symmetrically, the thermal stress caused by the thermal expansion of the first metal member due to the heat generation of the light emitting element is evenly distributed without being unevenly distributed. Since it can be dispersed, it is possible to prevent cracking of the package and the like, prevent deterioration of the adhesion of the material such as the package, and effectively prevent peeling.

Furthermore, since the light-transmitting coating material is embedded in the recess, the package material can be prevented from being directly deteriorated by heat and light of the light emitting element, and is contained in the light-transmitting coating member. The fluorescent material makes it possible to extract light with high luminance and arbitrary color tone.
In addition, since the collar portion of the first metal member has a gradually widened region, the translucent coating material is covered by, for example, potting from the light emitting element in the recess to the collar portion. In this case, the surface tension of the light-transmitting coating material works appropriately, and the phenomenon that the light-transmitting coating material flows out from the first metal member can be avoided, and a desired portion can be appropriately covered.

Moreover, by providing a lens, the light irradiated from a light emitting element can be condensed, and directivity and a brightness | luminance can be improved.
Furthermore, since the wire length can be shortened by using the flange part close to the second metal member for mounting the protective element or wire bonding, it is possible to prevent the wire from being disconnected.
Accordingly, the characteristics of the light emitting device itself can be improved, and the lifetime can be extended in a highly reliable state.

Example 2
In the light emitting device of this embodiment, as shown in FIG. 3, a region 24 c that is gently wide is formed in a part of the region of the second metal member 24 that faces the first metal member 13. (The change in this case is an increase in the width of about 0.25 mm per 1 mm of the outer periphery of the wide portion), except that the protective element 12 is placed on the wide region 24c. The configuration is the same as that of the light emitting device.

  In this light emitting device, the same effect as that of the first embodiment is obtained, and the wide region 24c is formed in the second metal member 24 so that the distance between the first and second metal members 13 and 24 is closer. Thus, the connection between the light emitting element 11 and the protection element 12 and the first and second metal members 13 and 24 by the wire 16 can be performed more stably.

Example 3
In the light emitting device of this embodiment, as shown in FIG. 4A, a part of the region of the second metal member 34 facing the first metal member 13 is directed toward the first metal member 13. A wide region 34c protruding in this manner is formed (in this case, the change is an increase in width of about 0.5 mm per 1 mm of the outer periphery of the wide portion), and the protective element 12 is placed on the wide region 14c. Except for this, the configuration is substantially the same as that of the light-emitting device of Example 1.
This light emitting device can have the same effect as that of the second embodiment.

Example 4
In the light emitting device of this embodiment, as shown in FIG. 4B, a region 44 c that gradually increases in width is formed in a part of the region of the second metal member 44 that faces the first metal member 13. (The change in this case is an increase in the width of about 0.29 mm per 1 mm of the outer periphery of the wide portion), and the protective element 12 is placed on the wide region 44c. The first metal member 13 has substantially the same configuration as that of the light emitting device of Example 1 except that a substantially circular recess 13a and a flange 13b that surrounds the recess 13a and does not have a wide region are formed.
This light emitting device can have the same effect as that of the second embodiment.

  It 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.

It is a perspective view which shows one Embodiment of the light-emitting device of this invention. It is the top view and A-A 'line cross section of the metal member of the light-emitting device of FIG. It is a top view of the metal member in another embodiment of the light-emitting device of this invention. It is a top view of the metal member in another embodiment of the light-emitting device of this invention.

Explanation of symbols

10 light emitting device 11 light emitting element,
DESCRIPTION OF SYMBOLS 12 Protective element 13 1st metal member 13a Concave part 13b Eaves part 13c Wide area | region 14, 24, 34, 44 2nd metal member 14c, 24c, 34c, 44c Wide area | region 15 Package 16 Wire 17 Translucent coating | covering material 18 Lens

Claims (8)

A light emitting element; a protective element; a first and second metal member electrically connected to the light emitting element and the protective element; and a package in which at least part of the first and second metal members is embedded. A light emitting device,
The first metal member has a recess for placing the light emitting element and a flange that surrounds the recess, and the recess and the flange are opposed to the second metal member, and the flange A region formed with a constant width from the outer periphery of the recess between a side facing the second metal member and a side opposite to the facing side of the second metal member, and the second metal member A region that gradually becomes wider than the constant width as it approaches the second metal member on the side opposite to the second metal member, and a region that is narrower than the region that becomes wider on the side opposite to the opposite side of the second metal member. possess the area,
A protective element is placed on the widened region of the flange of the first metal member,
The light emitting device characterized that you have translucent covering material is embedded in at least the recess. The light emitting device according to claim 1, wherein the concave portion and the flange portion of the first metal member are formed in line symmetry in a plan view. The second metal member gradually increases in width toward the first metal member in a part of the region facing the first metal member, and the second metal member is formed in line symmetry in plan view. The light-emitting device according to claim 1 or 2 . The light-emitting device according to claim 3 , wherein a protective element is placed in a wide region of the second metal member. The light emitting device according to any one of claims 1 to 4, wherein a symmetric center line in plan view of the second metal member is arranged on an extension of the symmetric center line in plan view of the first metal member. . The light emitting device according to claim 5 , wherein the wide region in the second metal member is a region that gradually becomes wider. The light emitting device according to any one of claims 1-6 comprising a further lens in the light exit direction of the light emitting element. Translucent covering material, light-emitting device according to any one of claims 1 to 7 comprising a fluorescent substance.

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