JP4678392B2 - Light emitting device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device capable of enhancing reliability and improving optical output and method of manufacturing the same. <P>SOLUTION: A light emitting device is provided with a frame 40 surrounding an LED chop 10 at a mounting surface side of the LED chip 10 on a mounting substrate 20, an elastic sealing part 50 composed of the LED chip 10, and sealing resin material (silicon resin) for sealing the bonding wires 14, 14 in the frame 40, and a lens 60 arranged so as to overlap the sealing part 50, and the lens 60 and frame 40 are integrally formed by silicon resin which is the same transparent resin material. With a lens block LB composed of the lens 60 and frame 40, an injection hole 41 for injecting the sealing resin material into a space between the lens block LB and mounting substrate 20 and evacuation hole 42 for evacuating the surplus sealing resin material are formed. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a light emitting device using an LED chip (light emitting diode chip) and a method for manufacturing the same.

  Conventionally, an LED chip, a circuit board on which the LED chip is mounted, a metal (for example, aluminum) frame that surrounds the LED chip on the LED chip mounting surface side of the circuit board, and an inner side of the frame There has been proposed a light emitting device including a sealing portion made of a transparent resin (for example, epoxy resin, silicone resin, etc.) filled with an LED chip and sealed with a bonding wire connected to the LED chip (for example, a patent) References 1 and 2). Here, the frames described in Patent Documents 1 and 2 are formed in a shape in which the opening area gradually increases as the distance from the circuit board increases, and the inner side surface is a mirror surface, which is emitted from the LED chip. It also serves as a reflector that reflects light.

Further, in Patent Document 2, a blue phosphor that emits blue light is used as an LED chip, and a yellow phosphor that emits light when excited by light emitted from the blue LED chip on a transparent resin that seals the blue LED chip. There has been proposed a light-emitting device capable of obtaining an emission spectrum of white light by dispersing.
JP 2001-85748 A JP 2001-148514 A

  By the way, in the above-described light emitting device, when an epoxy resin is used as a material for the sealing portion, when a heat cycle test (temperature cycle test) in which a low temperature period of −40 ° C. and a high temperature period of 80 ° C. are alternately performed is performed. When the temperature is high, the bonding wire may be disconnected due to thermal expansion of the conductor pattern of the mounting substrate made of the circuit board. Moreover, the thing using an epoxy resin as a material of a sealing part had the malfunction that a weather resistance was low compared with the thing using a silicone resin.

  On the other hand, in the light emitting device described above, in the case where a silicone resin is used as the material of the sealing portion, the sealing portion is gel-like and elastic, and the bonding wire is not heated at the high temperature of the heat cycle test. Although it is possible to prevent disconnection, the linear expansion coefficient of the silicone resin that is the material of the sealing portion is a value that is 10 times or more that of aluminum that is the material of the frame, and the linear expansion coefficient of both Due to the difference, there was a problem that voids were generated in the sealing portion at low temperatures in the heat cycle test.

  Further, in the above light emitting device, the inner surface of the frame body is used as a mirror surface so that light from the LED chip is efficiently extracted to the outside of the sealing portion. There was a problem that light loss sometimes occurred.

  In addition, in the light emitting device described in Patent Document 1, when a configuration is adopted in which a lens that controls the light distribution of light emitted from the LED chip is disposed across the sealing portion and the frame body, Depending on the dimensional accuracy and assembly accuracy of the body and the lens, the optical axis of the LED chip and the lens may shift and the light output may decrease.

  Moreover, although the said patent document 2 has described the light-emitting device which made a part of the sealing part which seals the LED chip and the bonding wire connected to the LED chip into the shape of a convex lens, The stress generated in the sealing part when an external force is applied is transmitted to the LED chip and each bonding wire, which may cause fluctuations in the light emission characteristics of the LED chip and disconnection of the bonding wire, and moisture in the external atmosphere may be applied to the LED chip. There was a risk of reaching.

  The present invention has been made in view of the above-described reasons, and an object of the present invention is to provide a light-emitting device capable of improving reliability and improving light output and a method for manufacturing the same.

  The invention of claim 1 includes an LED chip, a mounting substrate on which the LED chip is mounted, a frame body that surrounds the LED chip on the mounting surface side of the LED chip, and an LED chip that is sealed inside the frame body. The lens and the frame are integrally formed of the same transparent resin material, and the lens and the frame are integrally formed of the same transparent resin material. The lens block is configured by forming an injection hole for injecting the sealing resin material into a space between the lens block and the mounting substrate and a discharge hole for discharging an excess of the sealing resin material. It is characterized by.

  According to the present invention, since the lens and the frame are integrally formed of the same transparent resin material, the frame and the sealing portion are compared with the case where the frame is formed of a metal material as in the prior art. The linear expansion coefficient difference can be reduced, and the generation of voids in the sealing portion at low temperatures in the heat cycle test can be suppressed, so that the reliability can be improved and the light of the frame body Since the occurrence of reflection loss can be suppressed, the light output can be improved. In addition, the number of parts can be reduced as compared with the case where the lens and the frame are separate members, and a decrease in light output due to the deviation of the optical axis between the LED chip and the lens can be prevented. According to the present invention, the lens block including the lens and the frame includes an injection hole for injecting the sealing resin material into a space between the lens block and the mounting substrate, and surplus of the sealing resin material. Since the discharge hole for discharging the portion is formed, it is possible to adopt a manufacturing method in which the sealing resin material is injected into the space surrounded by the lens block and the mounting substrate after the lens block is fixed to the mounting substrate. It becomes possible.

  According to a second aspect of the present invention, the light of the lens according to the first aspect of the invention includes a phosphor that emits light of a color different from the emission color of the LED chip when excited by the light emitted from the LED chip. A dome-shaped color conversion member disposed on the exit surface side is provided, and an air layer is formed between the color conversion member and the light exit surface of the lens and the outer surface of the frame. .

  According to the present invention, the phosphor that is excited by the light emitted from the LED chip and emits light of a color different from the emission color of the LED chip is included and disposed on the light emitting surface side of the lens. Since the dome-shaped color conversion member is provided, it is possible to obtain mixed color light of light emitted from the LED chip and light emitted from the phosphor, for example, white light can be obtained. Further, according to the present invention, since the color conversion member is formed in a dome shape, uneven color can be reduced by making the thickness of the color conversion member uniform. Further, according to the present invention, an air layer is formed between the color conversion member, the light emitting surface of the lens, and the outer surface of the frame, and it is not necessary to make the color conversion member adhere to the lens. The LED chip can suppress a decrease in yield due to the dimensional accuracy and positioning accuracy of the color conversion member, and the stress generated in the color conversion member when an external force is applied to the color conversion member through the lens and the sealing portion. Of the light that is emitted from the LED chip, is incident on the color conversion member through the sealing portion and the lens, and is scattered by the phosphor particles in the color conversion member. The advantage is that the amount of light scattered to the side and transmitted through the lens can be reduced, and the light extraction efficiency to the outside as the entire apparatus can be improved, and the moisture in the external atmosphere There is an advantage that hardly reaches the serial LED chip.

  According to a third aspect of the present invention, in the second aspect of the present invention, in the lens according to the second aspect, the light is emitted from a light incident surface on the sealing portion side at the boundary between the light emitting surface and the air layer. It is formed in a convex curved surface shape that does not totally reflect.

  According to the present invention, the light emitted from the LED chip can easily reach the color conversion member without being totally reflected at the boundary between the light emitting surface and the air layer, and the total luminous flux can be increased. .

  According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the mounting substrate is made of a heat conductive material and includes a heat transfer plate on which the LED chip is mounted, and the LED chip and the heat transfer plate. A submount member interposed between the LED chip and the heat transfer plate to relieve stress acting on the LED chip due to a difference in linear expansion coefficient between the LED chip and the heat transfer plate; and a surface opposite to the heat transfer plate side A pair of lead patterns that are electrically connected to both electrodes of the LED chip are provided, and a window hole that exposes the submount member is formed through an insulating substrate that penetrates in the thickness direction and is laminated on the heat transfer plate. It is characterized by.

  According to the present invention, the heat generated in the LED chip can be efficiently radiated through the submount member and the heat transfer plate, and also due to the difference in linear expansion coefficient between the LED chip and the heat transfer plate. The stress acting on the LED chip can be relaxed.

  According to a fifth aspect of the present invention, in the fourth aspect of the invention, the submount member has a surface on the submount member side of the LED chip that is more heat conductive than an edge of the color conversion member on the mounting substrate side. The thickness dimension is set so as to be located away from the plate.

  According to this invention, it is possible to prevent light emitted from the LED chip from being emitted sideways through the joint portion between the color conversion member and the mounting substrate.

  The invention of claim 6 is the method for manufacturing the light emitting device according to any one of claims 1 to 5, wherein after mounting the LED chip on the mounting substrate, the lens block is fixed to the mounting substrate. Then, filling a space surrounded by the lens block and the mounting substrate with an uncured sealing resin material through the injection hole of the lens block, and then curing the sealing resin material to form a sealing portion. Features.

  According to the present invention, it is possible to provide a light emitting device that can improve reliability, improve light output, and reduce costs. In addition, after mounting the LED chip on the mounting substrate, a sealing resin material serving as a sealing portion is injected inside the lens block, and then the lens block is positioned with respect to the mounting substrate to cure the sealing resin material. As compared with the case where a manufacturing method for forming the sealing portion is employed, there is an advantage that voids are hardly generated in the sealing portion during the manufacturing process.

  The invention of claim 7 is the method for manufacturing a light emitting device according to any one of claims 1 to 5, wherein after the LED chip is mounted on the mounting substrate, the LED chip is part of the sealing portion. The first sealing resin material is covered with an uncured first sealing resin material, and then the lens block is fixed to the mounting substrate, and then the same material as the first sealing resin material is entered into the space surrounded by the lens block and the mounting substrate. And filling the uncured second sealing resin material, which becomes the other part of the sealing portion, through the injection hole of the lens block, and then curing each sealing resin material to form the sealing portion. It is characterized by.

  According to the present invention, it is possible to provide a light emitting device that can improve reliability, improve light output, and reduce costs. Further, as compared with the invention of claim 6, there is an advantage that voids are hardly generated in the sealing portion during the manufacturing process.

  In the invention of claim 1, there is an effect that the reliability can be enhanced and the light output can be improved. In the invention of claim 1, it is possible to adopt a manufacturing method in which a sealing resin material is injected into a space surrounded by the lens block and the mounting substrate after the lens block is fixed to the mounting substrate. There is.

  According to the sixth and seventh aspects of the invention, there is an effect that it is possible to provide a light emitting device with high reliability and high light output.

  First, after describing a reference example of the light emitting device, the light emitting device of the embodiment will be described.

(Reference Example 1)
Hereinafter, the light emitting device of this reference example will be described with reference to FIGS.

  The light emitting device 1 of the present reference example includes an LED chip 10, a mounting substrate 20 on which the LED chip 10 is mounted, a frame 40 that surrounds the LED chip 10 on the mounting surface side of the LED chip 10 on the mounting substrate 20, and a frame The LED chip 10 and the bonding wires 14 and 14 connected to the LED chip 10 inside the body 40 are made of a sealing resin material that seals, and the elastic sealing part 50 is disposed so as to overlap the sealing part 50. The lens 60 and a phosphor that is excited by the light emitted from the LED chip 10 and emits light of a color different from the emission color of the LED chip 10 together with a transparent material. A dome-shaped color conversion member 70 that covers the lens 60 on the surface 60b side and is disposed in such a manner that an air layer 80 is formed between the light emitting surface 60b and the frame body 40 is provided. Ri, the lens 60 and the frame body 40 are integrally formed by the same transparent resin material.

  The light emitting device 1 of the present reference example is used as a light source of a lighting fixture, for example, and is made of a metal (for example, a metal having a high thermal conductivity such as Al or Cu) through an insulating layer 90 made of, for example, a green sheet. Since the heat resistance from the LED chip 10 to the instrument body 100 can be reduced and the heat dissipation can be improved, and the temperature rise of the junction temperature of the LED chip 10 can be suppressed. The optical output can be increased and the optical output can be increased. Here, in the case of a lighting fixture, a plurality of light emitting devices 1 are mounted on the fixture body 100 so that a desired light output is obtained, and the plurality of light emitting devices 1 are connected in series or in parallel. That's fine.

  The mounting board 20 is provided with a metal plate 21 and a pair of lead patterns 23 and 23 electrically connected to both electrodes (not shown) of the LED chip 10 on the surface opposite to the metal plate 21 side. The insulating substrate 22 includes a laminated glass epoxy (FR4) substrate and a submount member 30 described later. A window hole 24 that exposes the submount member 30 is provided in the insulating substrate 22 in the thickness direction. The heat generated in the LED chip 10 can be transferred to the submount member 30 and the metal plate 21 without passing through the insulating substrate 22. Here, Cu is employed as the material of the metal plate 21, but any metal material having a relatively high thermal conductivity may be used, and not only Cu but Al or the like may be employed. In the present reference example, the metal plate 21 is made of a heat conductive material and constitutes a heat transfer plate on which the LED chip 10 is mounted. The metal plate 21 and the insulating substrate 22 are a bonding metal layer 25 (FIG. 2 and FIG. 6) made of a metal material (here, Cu) formed on the surface of the insulating substrate 22 facing the metal plate 21. Fixed) via Each lead pattern 23 is composed of a laminated film of a Cu film, a Ni film, and an Ag film. On the surface of the insulating substrate 22 opposite to the metal plate 21 side, a resist layer 26 (see FIGS. 2 and 6) made of a white resin is laminated so as to cover the lead patterns 23 and 23. The resist layer 26 is formed with a circular opening window 26a exposing the inner lead portions 23a, 23a of the lead patterns 23, 23 at the center, and the outer lead portions 23b of the lead patterns 23, 23 at the periphery. Circular opening windows 26b and 26b are formed to expose each of 23b.

  The LED chip 10 is a GaN-based blue LED chip that emits blue light, and is a conductive substrate made of an n-type SiC substrate that has a lattice constant and a crystal structure close to GaN as a crystal growth substrate and has conductivity compared to a sapphire substrate. The light emitting portion 12 formed of a GaN-based compound semiconductor material and having, for example, a double hetero structure is formed on the main surface side of the conductive substrate 11 by an epitaxial growth method (for example, MOVPE method). ), A cathode electrode (n electrode) which is a cathode side electrode (not shown) is formed on the back surface of the conductive substrate 11, and is shown on the surface of the light emitting unit 12 (the outermost surface on the main surface side of the conductive substrate 11). An anode electrode (p electrode) which is an electrode on the anode side that is not to be formed is formed. In short, the LED chip 10 has an anode electrode formed on one surface side and a cathode electrode formed on the other surface side. The cathode electrode and the anode electrode are composed of a laminated film of a Ni film and an Au film, but the material of the cathode electrode and the anode electrode is not particularly limited, and a material capable of obtaining good ohmic characteristics For example, Al or the like may be employed. In this reference example, the LED chip 10 is mounted on the metal plate 21 so that the light emitting part 12 of the LED chip 10 is farther from the metal plate 21 than the conductive substrate 11. The conductive plate 11 may be mounted on the metal plate 21 so as to be closer to the metal plate 21 than the conductive substrate 11. Considering the light extraction efficiency, it is desirable to arrange the light emitting part 12 on the side away from the metal plate 21, but in this reference example, the conductive substrate 11 and the light emitting part 12 have the same refractive index. Therefore, even if the light emitting unit 12 is disposed on the side close to the metal plate 21, the light extraction loss does not become too large.

  Further, the LED chip 10 is formed on the metal plate 21 in the shape of a rectangular plate having a size larger than the chip size of the LED chip 10, and the LED chip 10 is caused by the difference in linear expansion coefficient between the LED chip 10 and the metal plate 21. It is mounted via a submount member 30 that relieves stress acting on the chip 10. The submount member 30 has not only a function of relieving the stress, but also a heat conduction function of transferring heat generated in the LED chip 10 to a range wider than the chip size of the LED chip 10 on the metal plate 21. . In this reference example, AlN having a relatively high thermal conductivity and insulation is adopted as the material of the submount member 30, and the LED chip 10 has the cathode electrode on the LED chip 10 side of the submount member 30. Electrically connected to one lead pattern 23 through a conductor wire 31 provided on the surface and connected to the cathode electrode (see FIG. 5) and a bonding wire 14 made of a thin metal wire (for example, a gold wire, an aluminum wire). The anode electrode is electrically connected to the other lead pattern 23 via the bonding wire 14. The LED chip 10 and the submount member 30 may be bonded using, for example, solder such as SnPb, AuSn, SnAgCu, or silver paste, but may be bonded using lead-free solder such as AuSn, SnAgCu. It is preferable. In the submount member 30, a reflective film (for example, a laminated film of a Ni film and an Ag film) that reflects light emitted from the LED chip 10 is formed around the conductor pattern 31.

  The material of the submount member 30 is not limited to AlN, and any material may be used as long as the linear expansion coefficient is relatively close to 6H—SiC that is the material of the conductive substrate 11 and the heat conductivity is relatively high. Si or the like may be employed. In this reference example, since the LED chip 10 is mounted on the metal plate 21 via the submount member 30, the heat generated by the LED chip 10 can be efficiently radiated via the submount member 30 and the metal plate 21. In addition, the stress acting on the LED chip 10 due to the difference in linear expansion coefficient between the LED chip 10 and the metal plate 21 can be relaxed.

  The silicone resin is used as the sealing resin material of the sealing portion 50 described above, but is not limited to the silicone resin, and for example, an acrylic resin may be used.

  The frame body 40 is formed in an annular shape as shown in FIG. 4, and the lens 60 has a light incident surface 60a on the sealing portion 50 side formed in a flat shape and a light emitting surface 60b in a convex curved surface shape. It is formed into a formed plano-convex lens shape.

  Here, as described above, the lens 60 and the frame body 40 are integrally formed of the same transparent resin material (here, silicone resin) (in other words, the lens 60 and the frame body 40 are integrally formed integrally. The refractive index and the linear expansion coefficient are the same as those of the sealing portion 50. The lens 60 and the frame body 40 may be integrally formed of a transparent resin material that does not fall below the refractive index and elastic modulus of the sealing resin material of the sealing portion 50. For example, when the sealing resin material is an acrylic resin Alternatively, the lens 60 and the frame body 40 may be integrally formed with an acrylic resin. Moreover, the transparent resin material of the lens 60 and the frame 40 should just have a linear expansion coefficient equivalent to the linear expansion coefficient of sealing resin material.

  By the way, the lens 60 has a light emitting surface 60b formed in a convex curved surface shape that does not totally reflect the light incident from the light incident surface 60a at the boundary between the light emitting surface 60b and the air layer 80 described above. Here, the lens 60 is formed such that the light emitting surface 60 b is formed by a part of a spherical surface, and the center of the spherical surface is positioned on the center line of the light emitting unit 12 along the thickness direction of the LED chip 10. Yes. In other words, the lens 60 is disposed so that the optical axis of the lens 60 is located on the center line of the light emitting unit 12 along the thickness direction of the LED chip 10. Therefore, the light emitted from the LED chip 10 and incident on the light incident surface 60a of the lens 60 can easily reach the color conversion member 70 without being totally reflected at the boundary between the light emitting surface 60b and the air layer 80. The luminous flux can be increased. The light emitted from the side surface of the LED chip 10 propagates through the sealing portion 50 and the air layer 80 to reach the color conversion member 70 and does not excite the phosphor of the color conversion member 70 or collide with the phosphor. Or the color conversion member 70 is transmitted.

  The color conversion member 70 is a molded article in which a transparent material such as a silicone resin and a particulate yellow phosphor that emits broad yellow light when excited by the blue light emitted from the LED chip 10 are mixed. (That is, the color conversion member 70 contains a phosphor). Therefore, in the light emitting device 1 of the present reference example, the blue light emitted from the LED chip 10 and the light emitted from the yellow phosphor are emitted through the outer surface 70b of the color conversion member 70 to obtain white light. Can do. Note that the transparent material used as the material of the color conversion member 70 is not limited to the silicone resin, and for example, an acrylic resin, an epoxy resin, glass, or the like may be employed. Further, the phosphor mixed with the transparent material used as the material of the color conversion member 70 is not limited to the yellow phosphor. For example, white light can be obtained by mixing a red phosphor and a green phosphor.

  Here, the color conversion member 70 has an inner surface 70 a formed in a shape along the light emitting surface 60 b of the lens 60. Therefore, the distance between the light emitting surface 60b and the inner surface 70a of the color conversion member 70 in the normal direction is a substantially constant value regardless of the position of the light emitting surface 60b of the lens 60. In addition, the color conversion member 70 is shape | molded so that the thickness along a normal line direction may become uniform irrespective of a position. The color conversion member 70 may be joined to the mounting substrate 20 using, for example, an adhesive (for example, a silicone resin, an epoxy resin, or the like) at the periphery of the opening.

  By the way, in the light emitting device 1 of the present reference example, the thickness dimension of the submount member 30 described above is such that the surface of the LED chip 10 on the submount member 30 side is a metal plate than the edge of the color conversion member 70 on the mounting substrate 20 side. The light emitted from the LED chip 10 to the side can be prevented from being emitted through the joint portion between the color conversion member 70 and the mounting substrate 20 (that is, the light is emitted from the LED chip 10). The blue light emitted from the LED chip 10 can be prevented from being emitted outside without passing through the color conversion member 70). Here, in the light emitting device 1 of the present reference example, the LED chip 10 is disposed at a position separated from the plane including the outermost surface of the mounting substrate 20 (the surface of the resist layer 26) in the normal direction of the plane. In the lens block LB composed of the lens 60 and the frame body 40, the space surrounded by the lens 60 and the frame body 40 constitutes a housing recess for housing the LED chip 10.

  As a manufacturing method of the light emitting device 1 of this reference example, as shown in FIG. 8, after the LED chip 10 and the bonding wires 14 and 14 are connected, the above-described sealing is performed in a space surrounded by the lens 60 and the frame body 40. After injecting a liquid sealing resin material (for example, silicone resin) 50c to be the stopper 50, the lens 60 is disposed opposite to the mounting substrate 20 with the frame body 40 interposed between the lens 60 and the mounting substrate 20. A manufacturing method in which the sealing portion 50 is formed by curing the sealing resin material 50c is conceivable. However, in such a manufacturing method, a void may occur in the sealing portion 50 during the manufacturing process.

  Therefore, in the manufacture of the light emitting device 1 of the present reference example, as shown in FIG. 7, the LED chip 10 is mounted on the mounting substrate 20 and the LED chip 10 and the bonding wires 14 and 14 are connected, and then the LED chip 10. The bonding wires 14 and 14 are covered with a liquid first sealing resin material (for example, a silicone resin) 50 a that becomes a part of the sealing portion 50, and then the second space is surrounded by the lens 60 and the frame body 40. A liquid second sealing resin material (for example, silicone resin) 50b made of the same material as that of the first sealing resin material 50a and serving as another part of the sealing portion 50 is injected, and then the lens 60 is mounted on the mounting substrate 20. The sealing portion 50 is formed by curing the sealing resin materials 50a and 50b with the frame body 40 interposed therebetween so as to be opposed to the mounting substrate 20. According to such a manufacturing method, it is difficult to generate a void in the sealing portion 50 during the manufacturing process, and it is possible to provide the light emitting device 1 with high reliability and high light output. Here, if the first sealing resin material 50a is cured before injecting the second sealing resin material 50b, the viscosity of the first sealing resin material 50a is reduced, and the inside of the housing recess is reduced. There is an advantage that the trapped voids are easily removed. In this reference example, the inner diameter of the circular opening window 26a formed in the central portion of the resist layer 26 of the mounting substrate 20 is set to be slightly larger than the maximum outer diameter of the color conversion member 40. When the first sealing resin material 50a is potted, the first sealing resin material 50a that flows into the vicinity of the inner peripheral surface of the opening window 26a is used as an adhesive for joining the color conversion member 70 and the mounting substrate 20 together. ing.

  In the light emitting device 1 of the present reference example described above, the lens 60 and the frame body 40 are integrally formed of the same transparent resin material, so that the frame body is formed of a metal material as in the conventional case. Thus, the difference in linear expansion coefficient between the frame body 40 and the sealing portion 50 can be reduced, and generation of voids in the sealing portion 50 can be suppressed at a low temperature in the heat cycle test, thereby improving reliability. In addition, since it is possible to suppress the occurrence of light reflection loss in the frame body 40, the light output can be improved. In addition, the number of components can be reduced as compared with the case where the lens 60 and the frame body 40 are separate members, and a decrease in light output due to the deviation of the optical axis between the LED chip 10 and the lens 60 can be prevented. .

  Further, in the light emitting device 1 of this reference example, the color conversion member 70 may be disposed in a form in which an air layer 80 is formed between the light emitting surface 60 b of the lens 60 and the frame body 40. Since it is not necessary for the lens 60 and the frame 40 to be in close contact with each other, it is possible to suppress a decrease in yield due to the dimensional accuracy and positioning accuracy of the color conversion member 70. Further, in the light emitting device 1 of this reference example, since the assembly of the color conversion member 70 is the final process at the time of assembly, the color conversion member 70 in which the blending of the phosphor with respect to the transparent material is adjusted according to the emission wavelength of the LED chip 10. By using, color variations can be reduced. In addition, since the color conversion member 70 is formed in a dome shape, uneven color can be reduced by making the thickness of the color conversion member 70 uniform.

  Further, in the light emitting device 1 of the present reference example, since the air layer 80 is formed between the color conversion member 70 and the lens 60 as described above, the color conversion member when an external force acts on the color conversion member 70. The possibility that the lens 70 is deformed and abutted against the lens 60 is reduced, and the stress generated in the color conversion member 70 due to the external force is transmitted to the LED chip 10 and the bonding wires 14 and 14 through the lens 60 and the sealing portion 50. Therefore, there is an advantage that reliability is improved because fluctuations in the light emission characteristics of the LED chip 10 due to the external force and disconnection of the bonding wires 14 and 14 are less likely to occur. In addition, since the air layer 80 is formed between the color conversion member 70 and the lens 60, there is an advantage that moisture in the external atmosphere hardly reaches the LED chip 10.

  In addition, since the air layer 80 is formed between the color conversion member 70 and the lens 60, the color conversion member 70 is emitted from the LED chip 10 and enters the color conversion member 70 through the sealing portion 50 and the lens 60. Among the light scattered by the yellow phosphor particles in 70, there is an advantage that the amount of light scattered to the lens 60 side and transmitted through the lens 60 can be reduced, and the light extraction efficiency to the outside as the entire apparatus can be improved. is there.

  Here, as shown in FIGS. 9A and 9B, the optical axis of the color conversion member 70 and the optical axis of the LED chip 10 coincide with each other, and the central position of the color conversion member 70 in the optical axis direction. It is assumed that the blue light from the LED chip 10 is scattered in all directions by P, the total reflection angle at the interface between the color conversion member 70 and the air layer 80 is φa, and the color conversion member 70 and the outside of the color conversion member 70 are outside. The total reflection angle at the interface with air, which is the medium, is φb, and the light scattered at the position P is 2θa, the spread angle of the escape cone ECa on the inner surface 70a side of the color conversion member 70, and the color is scattered with respect to the light scattered at the position P. If the spread angle of the escape cone ECb on the outer surface 70b side of the conversion member 70 is 2θb, as shown in FIG. 9A, when the total reflection angles φa and φb are 40 °, 2θa = 60 ° and 2θb = 98 °. As shown in FIG. 9B, the total reflection angle When φa and φb are 50 °, 2θa = 76 ° and 2θb = 134 °.

Here, if the refractive index of the transparent material used for the color conversion member 70 is n, and the maximum emission efficiency of blue light scattered at the position P and emitted through the escape cone ECa on the inner surface 70a is η, η = ( ¼n ² ) × 100 [%], so that when silicone resin is used as the transparent material as described above, η≈13% when n = 1.4. Therefore, when the air layer 80 is not formed between the color conversion member 70 and the lens 60, 50% of the blue light scattered at the position P returns to the lens 60, whereas the air layer Since 80 is formed, only 13% of the blue light scattered at the position P returns to the lens 60, so that deterioration of the sealing portion 50 due to the blue light can be suppressed. In order to reduce the blue light emitted through the escape cone ECa, it is desirable to increase the thickness of the color conversion member 70.

(Reference Example 2)
The basic configuration of the light emitting device 1 of the present reference example shown in FIG. 10 is substantially the same as that of the reference example 1, and the inner diameter of the opening window 26a at the center of the resist layer 26 is set slightly smaller than the maximum inner diameter of the color conversion member 70. The difference is that the edge of the color conversion member 70 on the mounting substrate 20 side and the peripheral portion of the opening window 26a in the resist layer 26 are joined by the joining portion 75 made of an adhesive over the entire circumference. . In addition, the same code | symbol is attached | subjected to the component similar to the reference example 1, and description is abbreviate | omitted.

  Therefore, in manufacturing the light emitting device 1 of the present reference example, as in the reference example 1, as shown in FIG. 11, the LED chip 10 is mounted on the mounting substrate 20 and the LED chip 10 and the bonding wires 14 and 14 are connected. Then, the LED chip 10 and the bonding wires 14 and 14 are covered with a liquid first sealing resin material (for example, silicone resin) 50a which becomes a part of the sealing portion 50, and then the lens 60, the frame body 40, A liquid second sealing resin material (for example, silicone resin) 50b made of the same material as the first sealing resin material 50a and serving as another part of the sealing portion 50 is injected into the space surrounded by The sealing portion 50 is formed by curing the sealing resin materials 50a and 50b by disposing the lens 60 opposite to the mounting substrate 20 with the frame 40 interposed between the lens 60 and the mounting substrate 20. However, the resist layer 26 prevents the first sealing resin material 50a from flowing out to the joint portion of the color conversion member 70, and the edge of the color conversion member 70 on the mounting substrate 20 side is Is bonded by an adhesive, so that the thickness of the bonding portion 75 interposed between the color conversion member 70 and the mounting substrate 20 can be easily controlled, and the reliability of the bonding between the color conversion member 70 and the mounting substrate 20 can be controlled. Improves. In addition, it is desirable to use the same material as the color conversion member 70 as the adhesive of the joint portion 75.

(Embodiment)
The basic configuration of the light emitting device 1 of the present embodiment shown in FIG. 1 is substantially the same as that of the reference example 1, and the lens block LB composed of the lens 60 and the frame body 40 is combined with the lens block LB and the mounting substrate 20. After the injection hole 41 for injecting the sealing resin material into the space between them and the discharge hole 42 for discharging the surplus of the sealing resin material are formed, the lens block LB is fixed to the mounting substrate 20. A manufacturing method in which a sealing resin material is injected into a space surrounded by the mounting substrate 20 and the lens block LB can be employed. In addition, the same code | symbol is attached | subjected to the component similar to the reference example 1, and description is abbreviate | omitted.

  In manufacturing the light emitting device 1 of the present embodiment, for example, the LED chip 10 is mounted on the mounting substrate 20 and the LED chip 10 and the bonding wires 14 and 14 are connected, and then the mounting substrate 20 is connected via the lens block LB. After fixing, the space surrounded by the lens block LB and the mounting substrate 20 is filled with an uncured sealing resin material through the injection hole 41 of the lens block LB, and then the sealing resin material is cured to be sealed. It is only necessary to form the stopper 50 and then fix the color conversion member 70 to the mounting substrate 20. By adopting such a manufacturing method, it is possible to improve the reliability and improve the light output, and It is possible to provide the light emitting device 1 capable of reducing the cost. Further, after the LED chip 10 and the bonding wires 14 and 14 are connected, a sealing resin material that becomes the sealing portion 50 is injected inside the lens block LB, and then the lens block LB is positioned with respect to the mounting substrate 20. As compared with a case where a manufacturing method in which the sealing portion 50 is formed by curing the sealing resin material is employed, there is an advantage that voids are hardly generated in the sealing portion 50 during the manufacturing process.

  In manufacturing the light emitting device 1 of the present embodiment, for example, after the LED chip 10 is mounted on the mounting substrate 20 and the LED chip 10 and the bonding wires 14 and 14 are connected, the LED chip 10 and the bonding wires 14 and 14 are connected. 14 is covered with an uncured first sealing resin material that becomes a part of the sealing portion 50, and then the lens block LB is fixed to the mounting substrate 20, and then surrounded by the lens block LB and the mounting substrate 20. The uncured second sealing resin material, which is made of the same material as the first sealing resin material and becomes the other part of the sealing portion 50, is filled into the space through the injection hole 41 of the lens block LB. The sealing portion 50 may be formed by curing the first sealing resin material and the second sealing resin material, and voids are less likely to be generated in the sealing portion 50 during the manufacturing process. There is an advantage in that.

  By the way, in each above-mentioned reference example and embodiment, the blue LED chip whose luminescent color is blue is employ | adopted as the LED chip 10, and the SiC substrate is employ | adopted as the electroconductive board | substrate 11, but it replaces with a SiC substrate. A GaN substrate may be used. When a SiC substrate or a GaN substrate is used, the crystal growth substrate has a higher thermal conductivity than the case where a sapphire substrate, which is an insulator, is used as the crystal growth substrate. The thermal resistance of the growth substrate can be reduced. Further, the light emission color of the LED chip 10 is not limited to blue, and may be, for example, red or green. That is, the material of the light-emitting portion 12 of the LED chip 10 is not limited to the GaN-based compound semiconductor material, and a GaAs-based compound semiconductor material, a GaP-based compound semiconductor material, or the like may be employed according to the emission color of the LED chip 10. Further, the conductive substrate 11 is not limited to the SiC substrate, and may be appropriately selected from, for example, a GaAs substrate and a GsP substrate according to the material of the light emitting unit 12. Further, when the difference in linear expansion coefficient between the LED chip 10 and the mounting substrate 20 is relatively small, the submount member 30 described in each reference example and embodiment is not necessarily provided. Further, the mounting substrate 20 may employ a structure other than the structure described in each reference example and embodiment.

It is a schematic sectional drawing of the light-emitting device of embodiment. 6 is a schematic cross-sectional view of a light emitting device of Reference Example 1. FIG. It is a general | schematic disassembled perspective view in which the light emitting device same as the above was partially broken. It is a principal part schematic plan view of a light-emitting device same as the above. It is a schematic perspective view of the submount member in a light emitting device same as the above. The insulating board | substrate in a light-emitting device same as the above is shown, (a) is a schematic plan view, (b) is a schematic cross-sectional view taken along the line ABCD of (a), and (c) is a schematic bottom view partially broken. is there. It is explanatory drawing of the manufacturing method of a light-emitting device same as the above. It is explanatory drawing of the manufacturing method of a light-emitting device same as the above. It is principal part explanatory drawing of a light-emitting device same as the above. 10 is a schematic cross-sectional view of a light emitting device of Reference Example 2. FIG. It is explanatory drawing of the manufacturing method of a light-emitting device same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 10 LED chip 14 Bonding wire 20 Mounting board 21 Metal plate (heat-transfer plate)
22 Insulating substrate 23 Lead pattern 26 Resist layer 30 Submount member 40 Frame body 41 Injection hole 42 Ejection hole 50 Sealing part 60 Lens 70 Color conversion member 80 Air layer LB Lens block

Claims (7)

  An LED chip, a mounting substrate on which the LED chip is mounted, a frame body that surrounds the LED chip on the mounting surface side of the LED chip on the mounting substrate, and a sealing resin material that seals the LED chip inside the frame body A lens block that includes a lens and a frame, the lens and the frame are integrally formed of the same transparent resin material. Is a light emitting device characterized in that an injection hole for injecting the sealing resin material and a discharge hole for discharging an excess of the sealing resin material are formed in a space between the lens block and the mounting substrate.   A dome-like color conversion member disposed on the light emitting surface side of the lens, containing a phosphor that is excited by light emitted from the LED chip and emits light of a color different from the emission color of the LED chip 2. The light emitting device according to claim 1, wherein an air layer is formed between the color conversion member, the light emitting surface of the lens, and the outer surface of the frame.   In the lens, the light exit surface is formed in a convex curved surface shape that does not totally reflect the light incident from the light incident surface on the sealing portion side at the boundary between the light exit surface and the air layer. The light emitting device according to claim 2.   The mounting substrate is made of a heat conductive material, the heat transfer plate on which the LED chip is mounted, and the wire between the LED chip and the heat transfer plate interposed between the LED chip and the heat transfer plate. A submount member that relieves stress acting on the LED chip due to a difference in expansion coefficient, and a pair of lead patterns electrically connected to both electrodes of the LED chip on the surface opposite to the heat transfer plate side The window hole which exposes a submount member and is provided is comprised from the insulating board | substrate penetrated in the thickness direction and laminated | stacked on the heat exchanger plate, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Light-emitting device.   The thickness of the submount member is set so that the surface of the LED chip on the submount member side is located farther from the heat transfer plate than the edge of the color conversion member on the mounting substrate side. The light-emitting device according to claim 4.   6. The method of manufacturing a light emitting device according to claim 1, wherein after mounting the LED chip on the mounting substrate, the lens block is fixed to the mounting substrate, and then the lens block and the mounting substrate are mounted. And filling a space surrounded by an uncured sealing resin material through the injection hole of the lens block, and then curing the sealing resin material to form a sealing portion. Method.   6. The method of manufacturing a light emitting device according to claim 1, wherein the LED chip is mounted on the mounting substrate, and then the LED chip becomes a part of the sealing portion. After the lens block is fixed to the mounting substrate, the space surrounded by the lens block and the mounting substrate is made of the same material as the first sealing resin material, and the sealing portion An uncured second sealing resin material that becomes a portion of the lens block is filled through the injection hole of the lens block, and then the sealing portion is formed by curing each sealing resin material. Production method.

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