JP2017201666A - Method for manufacturing light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a light-emitting device, which is superior in mass productivity.SOLUTION: The method for manufacturing a light-emitting device (100) according to an embodiment of the present invention comprises: a first step for using a die (80) having a plate-like base body (83) and protrusions (85) protruding from the base body (83) to form a first light reflective member (10) having holes (10p) formed by the protrusions (85); a second step for forming an optically-transmissive member (30) in each hole (10p); and a third step for gluing a light-emitting element (50) to the optically-transmissive member (30). The protrusions (85) each include a pillar portion (85a) and a frustum-like portion (85b) continuing to the base body (83) from the pillar portion (85a).SELECTED DRAWING: Figure 2A

Description

  The present disclosure relates to a method for manufacturing a light emitting device.

  For example, Patent Document 1 discloses a first step of mounting a plate-like optical member whose outer periphery is covered with an outer frame made of white ceramic on a light emitting element with an optical layer interposed therebetween, and an outer periphery of the optical layer and the plate. The manufacturing method of the light-emitting device which has the 2nd process of covering the outer periphery of the white ceramic outer frame of a glass-shaped optical member with a light-reflective resin material is described.

JP 2012-134355 A

  However, in the method for manufacturing a light emitting device described in Patent Document 1, the production cost of a plate-shaped optical member whose outer periphery is covered with a white ceramic outer frame is high, and is inferior in mass productivity.

  An object of one embodiment of the present invention is to provide a method for manufacturing a light-emitting device that is excellent in mass productivity.

  In a method for manufacturing a light emitting device according to an embodiment of the present invention, a first light reflecting member having a hole formed by a protrusion is formed using a mold having a plate-like base and a protrusion protruding from the base. A first step, a second step of forming a light transmissive member in the hole, and a third step of bonding a light emitting element to the light transmissive member, wherein the protrusion is formed from a columnar portion and the columnar portion. And a frustum-shaped portion continuous to the base.

  The method for manufacturing a light-emitting device according to an embodiment of the present invention can be configured mainly by resin molding, and is excellent in mass productivity.

1 is a schematic front view of a light emitting device according to an embodiment of the present invention. It is a schematic sectional drawing in the AA cross section of FIG. 1A. It is a schematic sectional drawing which shows the 1st process of the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing which shows the 2nd process of the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing which shows the 3rd process of the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing which shows the 4th process of the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing of the modification of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing of the modification of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing of the modification of the light-emitting device which concerns on one embodiment of this invention.

  Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the light-emitting device and the manufacturing method thereof described below are for embodying the technical idea of the present invention, and the present invention is not limited to the following unless otherwise specified. In addition, the size, positional relationship, and the like of members illustrated in the drawings may be exaggerated for clarity of explanation.

  The visible wavelength range is a wavelength range of 380 nm to 780 nm, the blue range is a wavelength range of 420 nm to 480 nm, the green range is a wavelength range of 500 nm to 570 nm, and the yellow range is longer than 570 nm to 590 nm. The following range, the red region, has a wavelength in the range of 610 nm to 750 nm. The main light emission direction of the light emitting device is “front”.

  1A is a schematic front view of a light-emitting device 100 according to an embodiment, and FIG. 1B is a schematic cross-sectional view taken along the line AA. 3, 4, and 5 are schematic cross-sectional views of modifications of the light emitting device 100 according to the embodiment.

  As shown in FIGS. 1A and 1B, a light emitting device 100 according to an embodiment is a chip size package (CSP) type light emitting diode (LED) device. The light emitting device 100 includes a first light reflecting member 10, a second light reflecting member 20, a light transmitting member 30, a light emitting element 50, an adhesive member 60, and an external connection terminal 70. The first light reflecting member 10 is a frame having an opening at the center. The light transmitting member 30 is provided in the opening. The light transmitting member 30 is supported on the inner surface of the opening of the first light reflecting member 10 over the entire circumference. The light transmissive member 30 is configured by a columnar first region 30a located in front and a frustum-shaped second region 30b continuous behind the first region 30a. The light transmitting member 30 contains a wavelength conversion substance 40. The wavelength converting substance 40 is unevenly distributed in the light transmitting member 30 on the front surface side, that is, on the first region 30a side. The light emitting element 50 is bonded to the rear surface of the light transmitting member 30 via an adhesive member 60. The adhesive member 60 covers at least a part of the side surface of the light emitting element 50. Positive and negative external connection terminals 70 are connected to the rear surface of the light emitting element 50. The second light reflecting member 20 is formed in contact with the rear surface of the first light reflecting member 10. The second light reflecting member 20 covers the entire circumference of the side of the light emitting element 50 through at least a partial region via the adhesive member 60 and other regions directly. In addition, the second light reflecting member 20 covers the entire side periphery of the positive and negative external connection terminals 70. The front surface of the light emitting device 100 is configured by the front surface of the first light reflecting member 10 and the front surface of the light transmitting member 30. The rear surface of the light emitting device 100 is configured by the rear surface of the second light reflecting member 20 and the rear surface of the positive and negative external connection terminals 70.

  The light emitting device 100 having such a configuration emits light when, for example, a positive and negative external connection terminal 70 is soldered to a circuit board or the like and power is supplied through the circuit. At this time, due to the high light reflectivity of the first light reflecting member 10 and the second light reflecting member 20, a lot of light emitted from the light emitting element 50 and the light transmitting member 30 to the side is deflected forward, and the light emitting device 100. The main light emitting region is the front surface of the light transmitting member 30. Therefore, the outline of the light emitting region is clear and light emission suitable for light distribution adjustment by an optical system such as a lens can be obtained.

  2A to 2D are schematic cross-sectional views illustrating the first to fourth steps of the method for manufacturing the light emitting device 100 according to the embodiment.

  In addition, the code | symbol with the parenthesis in this specification and drawing means that the component is in the state before reaching the final form, and more specifically, in a liquid or semi-cured state. Further, “liquid” in this specification includes sol form and slurry form.

  As shown in FIGS. 2A to 2C, the method of manufacturing the light emitting device 100 according to the embodiment includes the following first to third steps. Further, the method for manufacturing the light emitting device 100 according to the embodiment additionally includes a fourth step as shown in FIG. 2D.

  2A and 2B, the first step uses a mold (first mold) 80 having a plate-like base 83 and a protrusion 85 protruding from the base 83 to form a hole 10p formed by the protrusion 85. It is the process of forming the 1st light reflection member 10 which has these. Here, the protrusion 85 includes a columnar portion 85 a and a frustum-shaped portion 85 b continuous from the columnar portion 85 a to the base body 83. Specifically, the first mold 80 and the second mold 82 are, for example, one and the other of the upper and lower molds of the transfer molding machine. Then, the liquid material (10) of the first light reflecting member is filled into a molding space formed by closing the first mold 80 and the second mold 82, that is, a cavity, and is cured by heat treatment. In the illustrated example, the plate-like jig 90 is installed in the molding space, but the plate-like jig 90 can be omitted. By the first step, the first light reflecting member 10 becomes a plate-like or frame-like member having the hole 10p. As illustrated in FIG. 2B, the hole 10p includes a first space 10pa formed by the columnar portion 85a and a second space 10pb formed by the frustum-shaped portion 85b. The number of the protrusions 85 provided on one mold 80 may be one, but a plurality of protrusions 85 are preferable from the viewpoint of mass productivity, and the plurality of protrusions 85 are regularly arranged on the base 83. It is preferable. Further, the planar view shape of the protrusion 85, mainly the columnar portion 85a, may be appropriately selected according to the desired planar view shape of the light transmitting member 30, and may be a circular shape, a triangular shape, a hexagonal shape, etc. in addition to a rectangular shape. . However, in the case of a polygonal shape, the corner may be rounded due to processing accuracy.

  The second step is a step of forming the light transmitting member 30 in the hole 10p as shown in FIG. 2B. Specifically, the liquid material (30) of the light transmitting member is injected into the hole 10p of the first light reflecting member by, for example, a dropping (potting) method, and is cured by heat treatment in an oven or the like. As shown in FIG. 2C, the light transmitting member 30 includes the first region 30a formed in the first space 10pa and the second region 30b formed in the second space 10pb by the second step. become. In order to make the wavelength converting substance 40 unevenly distributed in the first region 30a side or the second region 30b side in the light transmitting member 30, the liquid material (30) of the light transmitting member injected into the hole 10p is completely cured. By the time, the wavelength conversion substance 40 is settled to the desired side by adjusting the orientation of the main surface of the first light reflecting member 10, that is, the hole 10p with respect to gravity. Further, the wavelength converting substance 40 may be forcibly unevenly distributed on a desired side by a centrifugal sedimentation method or the like.

  The third step is a step of bonding the light emitting element 50 to the light transmitting member 30 as shown in FIG. 2C. Here, the light emitting element 50 is bonded to one main surface of the light transmitting member 30 via the bonding member 60. Specifically, the liquid material (60) of the adhesive member is applied on one main surface of the light transmitting member 30, and the front side of the light emitting element 50 is placed thereon, and the liquid material (60 of the adhesive member) ) Is cured by heat treatment in an oven or the like. At this time, from the viewpoint of suppressing the formation of the light confinement region and efficiently guiding the light emitted from the light emitting element 50 to the light transmitting member 30, the adhesive member 60 should be within the main bonding surface of the light transmitting member 30. Is preferred. Moreover, the main bonding surface (the first region 30a side or the second region 30b side) of the light transmitting member 30 is selected by reversing the installation direction of the first light reflecting member 10, that is, the light transmitting member 30, during the bonding operation. Can do. The liquid material (60) for the adhesive member may be applied to the light emitting element 50 side. Further, the connection of the external connection terminal 70 to the light emitting element 50 may be performed before the third step or after the third step.

  The fourth step is a step of covering the periphery of the light emitting element 50 with the second light reflecting member 20 as shown in FIG. 2D. Specifically, the liquid material (20 of the second light reflecting member) so as to embed the light emitting element 50, the adhesive member 60, and the external connection terminal 70 on the first light reflecting member 10 by, for example, a dropping (potting) method. ) And cured by heat treatment in an oven or the like. In addition, similarly to the first step, the second light reflecting member 20 may be molded using a molding machine such as a compression molding machine or a transfer molding machine. Thereafter, the excessively formed second light reflecting member 20 is removed by grinding or blasting, and the surface of the external connection terminal 70 is exposed. Moreover, when using a molding machine, you may shape | mold the 2nd light reflection member 20, pressing the surface of the external connection terminal 70 with a metal mold | die so that the surface of the external connection terminal 70 may be exposed. In addition, after this 4th process, although the interface of the 1st light reflection member 10 and the 2nd light reflection member 20 may be observed, it is preferable not to be observed from a viewpoint of the adhesiveness of both members.

  Finally, the first light reflecting member 10 and the second light reflecting member 20 are cut by dicing or the like, and the light emitting device 100 is singulated as shown in FIGS. 1A and 1B. In the above grinding and dicing, when the light transmitting member 30 includes a manganese-activated fluoride-based phosphor that is relatively inferior in water resistance as the wavelength conversion material 40, it is preferable to use a dry apparatus.

  As described above, the method for manufacturing the light-emitting device 100 according to the embodiment can be mainly configured by molding a resin, is low in cost and rich in moldability, and has excellent mass productivity. In addition, by using a mold, the quality of the light emitting device can be stabilized and mass productivity can be further improved. Further, by using the mold, the inner surface of the hole 10p of the first light reflecting member, that is, the side surface of the light transmitting member 30 can be formed relatively smoothly, and the light emitted from the light emitting element 50 can be easily extracted efficiently.

  Hereinafter, the preferable form in the manufacturing method of the light-emitting device 100 which concerns on embodiment is explained in full detail.

  As shown in FIG. 2A, in the first step, the outer surface of the frustum-shaped portion 85b is preferably a concave curved surface. The projection 85 of the mold 80 is preferably formed by cutting a metal plate using an end mill from the viewpoint of mass productivity, and the outer surface of the frustum-shaped portion 85b formed by such cutting is a concave curved surface. It is because it is easy to become.

  As shown in FIG. 2A, in the first step, it is preferable to prepare a plate-like jig 90 having a through hole 90h and form a part of the first light reflecting member 10 in the through hole 90h. Thereby, the 1st light reflection member 10 can be hold | maintained on the plate-shaped jig | tool 90, the curvature of the 1st light reflection member 10 can be suppressed, and it is easy to handle the 1st light reflection member 10 in a next process. The planar view shape of the through-hole 90h can be selected as appropriate, and a circular shape is preferable from the viewpoint of ease of processing. A part of the first light reflecting member 10 formed in the through hole 90h remains as a convex portion when the first light reflecting member 10 is removed from the plate-shaped jig 90, but is removed by grinding or dicing. can do.

  As shown in FIG. 2C, in the third step, it is preferable that the light emitting element 50 is bonded to the second region 30 b side of the light transmitting member 30. Since the area of the main surface of the light transmitting member 30 on the second region 30 b side is larger than the area of the main surface of the light transmitting member 30 on the first region 30 a side, the light emitting element 50 is bonded to the main surface of the light transmitting member 30. It is easy to capture light emitted from the light emitting element 50. In addition, a projecting portion of the second region 30b projecting laterally from the side surface of the first region 30a (hereinafter referred to as “projecting portion of the second region 30b”) is located on the inner side of the light emitting device 100, and By covering the front and the rear with the first light reflecting member 10 and the second light reflecting member 20, respectively, the light transmitting member 30 can be prevented from peeling or dropping.

  As shown in FIG. 2C, when the light transmitting member 30 contains the wavelength conversion material 40 excited by the light of the light emitting element 50, in the second step, the wavelength conversion material 40 is unevenly distributed on the first region 30a side. preferable. When the light emitting element 50 is bonded to the second region 30b side of the light transmitting member 30 (see FIG. 1B), the protruding portion of the second region 30b is covered with the first light reflecting member 10 so that light is easily confined. It becomes a part. For this reason, the wavelength conversion substance 40 can be efficiently extracted by disposing the wavelength conversion substance 40 away from the projecting portion of the second area 30b toward the first area 30a. On the other hand, when the light emitting element 50 is bonded to the first region 30a side of the light transmissive member 30 (see FIG. 3), the wavelength converting substance 40 is positioned on the inner side of the light emitting device 100, and the wavelength converting substance 40 is moisture or the like. Easy to protect from the external environment. Moreover, when including the process of grinding the main surface by the side of the 2nd area | region 30b of the light transmissive member 30, degradation of the wavelength conversion substance 40 accompanying grinding of the light transmissive member 30 can be suppressed thru | or avoided.

  In the second step, it is preferable to form the recess 30r in the first region 30a or the second region 30b. In the third step, it is preferable to bond the light emitting element 50 in the recess 30r. Accordingly, it is easy to adhere the light emitting element 50 to the light transmitting member 30 while suppressing the wetting and spreading of the adhesive member 60. When the recess 30r is formed in the second region 30b (see FIG. 4), the position of the light emitting element 50 is moved forward by the recess 30r, so that light is incident on the projecting portion of the second region 30b and thereby Light confinement can be suppressed and light can be extracted efficiently. In FIG. 4, the recess 30 r is a portion that is recessed toward the first region 30 a with reference to the boundary line between the first light reflecting member 10 and the second light reflecting member 20. Such a recess 30r can be formed by injecting and curing the liquid material (30) of the light transmitting member in a state where a partial region in the hole 10p is closed with a mold or a jig. In addition, the recess 30r makes the amount of the liquid material (30) of the light transmitting member smaller than the volume of the hole 10p, and causes the peripheral portion of the liquid material (30) of the light transmitting member to crawl up on the inner surface of the hole 10p. For example, it can be formed by sinking the central portion of the liquid material (30) of the light transmitting member.

  In the third step, the light emitting element 50 may be bonded to the first region 30a side of the light transmitting member 30 (see FIGS. 3 and 5). As a result, the projecting portion of the second region 30b can be exposed to the external environment, and light confinement by the projecting portion of the second region 30b as described above can be suppressed or avoided. Further, by making the main surface on the second region 30b side where the area of the light transmitting member 30 is large as the light emitting surface of the light emitting device 100, the light extraction window is widened and light can be extracted efficiently.

  When the light transmitting member 30 contains the wavelength converting material 40 excited by the light of the light emitting element 50 and the light emitting element 50 is bonded to the first region 30a side of the light transmitting member 30, in the second step, the wavelength converting material 40 may be unevenly distributed on the second region 30b side (see FIG. 5). As a result, the light density in the vicinity of the wavelength converting substance 40 can be relatively lowered, whereby heat generation of the wavelength converting substance 40 can be suppressed, and temperature quenching of the wavelength converting substance 40 can be suppressed.

  After the first step, the method includes a step (fifth step) of grinding the main surface of the first light reflecting member 10 and removing at least a part of the first space 10pa and / or the second space 10pb. May be. In addition, after the second step, the main surface of the light transmitting member 30 is ground to remove a part of the first region 30a and / or at least a part of the second region 30b (fifth step or sixth step). ) May be provided. In particular, when the light emitting element 50 is bonded to the second region 30b side of the light transmissive member 30, a part of the second region 30b, more preferably all of the second region 30b is removed, so that the protruding portion of the second region 30b as described above is obtained. Light confinement due to can be suppressed or avoided.

  Hereafter, each component in the light-emitting device concerning embodiment of this invention is demonstrated.

(Light Emitting Device 100)
The light emitting device is, for example, an LED device. The light-emitting device of the above embodiment is a top emission type (also referred to as “top view type”), but can also be a side emission type (also referred to as “side view type”) depending on the configuration of the external connection terminal. is there. In the top emission type light emitting device, the mounting direction and the main light emitting direction are parallel to each other. In the side-emitting type light emitting device, the mounting direction and the main light emitting direction are perpendicular to each other. The front view shape of the light emitting device, that is, the shape viewed from the main light emitting direction can be selected as appropriate, but a rectangular shape is preferable in mass productivity. In particular, the shape of the front view when the light emitting device is a top emission type is preferably a square shape. On the other hand, the shape of the front view when the light emitting device is a side emission type is preferably a rectangular shape having a longitudinal direction and a short direction. Moreover, it is preferable that a light emitting element is also the shape of the front view similar to a light-emitting device.

(First light reflecting member 10, second light reflecting member 20)
From the viewpoint of forward light extraction efficiency, the first light reflecting member and the second light reflecting member preferably have a light reflectance at a light emission peak wavelength of 70% or more, preferably 80% or more. Is more preferable and 90% or more is even more preferable. Furthermore, the first light reflecting member and the second light reflecting member are preferably white. Therefore, it is preferable that the first light reflecting member and the second light reflecting member contain a white pigment in the base material.

  As the base material of the first light reflecting member and the second light reflecting member, a resin can be used, and a thermosetting resin is particularly preferable. For example, silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, diallyl phthalate resin Or these modified resins. Of these, silicone resins and modified silicone resins are preferred because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. The “modified resin” in this specification includes a hybrid resin. Moreover, the base material of a 1st light reflection member and a 2nd light reflection member may contain the filler similar to the base material of the below-mentioned light transmissive member. Moreover, it is preferable that the base material of the first light reflecting member and the base material of the second light reflecting member are the same type.

  White pigments are titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, zirconium oxide. One of them can be used alone, or two or more of them can be used in combination. The shape of the white pigment can be appropriately selected and may be indefinite or crushed, but is preferably spherical from the viewpoint of fluidity. The particle size of the white pigment is, for example, about 0.1 μm or more and 0.5 μm or less, but it is preferable that the white pigment is smaller in order to enhance the effect of light reflection and coating. The content of the white pigment in the first light reflecting member and the second light reflecting member can be selected as appropriate, but is preferably 10 wt% or more and 80 wt% or less, for example, from the viewpoint of light reflectivity and viscosity in liquid state, and 20 wt%. It is more preferably 75 wt% or less, and even more preferably 30 wt% or more and 70 wt% or less. Note that “wt%” is weight percent and represents the ratio of the weight of the material to the total weight of the first light reflecting member and the second light reflecting member.

(Light transmission member 30)
The light transmissive member is a member that is provided on the light emitting element and transmits light emitted from the light emitting element to the outside of the apparatus. The light transmitting member is composed of at least the following base material. Moreover, a light transmissive member can be functioned as a wavelength conversion member by containing the following wavelength conversion substances in a base material. However, the inclusion of the wavelength converting substance is not essential.

  The base material of the light transmissive member may be any material that transmits light emitted from the light emitting element. Note that “translucency” in the present specification means that the light transmittance at the emission peak wavelength of the light-emitting element is preferably 60% or more, more preferably 70% or more, and still more preferably 80%. % And more. As the base material of the light transmitting member, silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, diallyl phthalate resin, or modified resins thereof can be used. Of these, silicone resins and modified silicone resins are preferred because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. The light transmissive member can be configured by a single layer of one of these base materials or a stack of two or more of these base materials.

The base material of the light transmitting member may contain various fillers in the resin. Examples of the filler include silicon oxide, aluminum oxide, zirconium oxide, and zinc oxide. A filler can be used individually by 1 type of these or in combination of 2 or more types of these. In particular, silicon oxide having a small thermal expansion coefficient is preferable. Further, by using nanoparticles as the filler, scattering including blue light Rayleigh scattering of the light emitting element can be increased, and the amount of the wavelength conversion substance used can be reduced. Nanoparticles are particles having a particle size of 1 nm to 100 nm. Further, "particle size" herein, for example, it is defined by the D _50.

(Wavelength converting material 40)
The wavelength converting material absorbs at least a part of the primary light emitted from the light emitting element and emits secondary light having a wavelength different from that of the primary light. Thereby, it can be set as the light-emitting device which emits the mixed color light of the primary light of a visible wavelength, and secondary light, for example, white light. The wavelength converting substance can be used alone or in combination of two or more of the specific examples shown below. For example, in the case of one type, a phosphor emitting yellow light can be used, and in the case of two types, a first phosphor emitting green to yellow light and a second phosphor emitting red light can be used.

Examples of phosphors that emit green light include yttrium / aluminum / garnet phosphors (for example, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce) and lutetium / aluminum / garnet phosphors (for example, Lu ₃ (Al, Ga) ₅ ). O ₁₂ : Ce), terbium / aluminum / garnet phosphor (for example, Tb ₃ (Al, Ga) ₅ O ₁₂ : Ce) phosphor, silicate phosphor (for example (Ba, Sr) ₂ SiO ₄ : Eu) Chlorosilicate phosphor (for example, Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu), β sialon phosphor (for example, Si _6-z Al _z O _z N _{8 -z} : Eu (0 <z <4. 2)), SGS type phosphors (for example, SrGa ₂ S ₄ : Eu) and the like. As a phosphor emitting yellow light, an α sialon-based phosphor (for example, M _z (Si, Al) ₁₂ (O, N) ₁₆ (where 0 <z ≦ 2 and M is Li, Mg, Ca, Y, In addition, among the phosphors emitting green light, there are phosphors emitting yellow light, for example, yttrium / aluminum / garnet phosphors are Y By substituting part with Gd, the emission peak wavelength can be shifted to the longer wavelength side, and yellow light emission is possible, and some of these phosphors can emit orange light. Examples of the phosphor to be used include a nitrogen-containing calcium aluminosilicate (CASN or SCASN) phosphor (for example, (Sr, Ca) AlSiN ₃ : Eu), etc. In addition, a manganese activated fluoride-based phosphor Phosphor (general formula (I) A ₂ [M _1-a Mn _a F ₆ ] phosphor represented by formula (I) wherein A represents K, Li, Na, Rb, At least one selected from the group consisting of Cs and NH ₄ , M is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and a is 0 <a <0. A typical example of this manganese-activated fluoride phosphor is a manganese-activated potassium fluorosilicate phosphor (for example, K ₂ SiF ₆ : Mn).

(Light emitting element 50)
The light emitting element includes at least a semiconductor element structure, and in many cases further includes a substrate. Examples of the light emitting element include an LED chip. The front-view shape of the light-emitting element is preferably a rectangle, particularly a square shape or a rectangular shape that is long in one direction, from the viewpoint of mass productivity, but may be other shapes. For example, the hexagonal shape can increase the light coupling efficiency from the side surface of the light emitting element to the adhesive member covering the side surface, and can also increase the light emission efficiency. The side surface of the light emitting element or its substrate may be perpendicular to the front surface, or may be inclined inward or outward. The light emitting element preferably has positive and negative (p, n) electrodes on the same surface side. The number of light emitting elements mounted on one light emitting device is not limited to one and may be plural. The same applies to the light transmitting member. The plurality of light emitting elements can be connected in series or in parallel.

The semiconductor element structure preferably includes a stack of semiconductor layers, that is, at least an n-type semiconductor layer and a p-type semiconductor layer, and an active layer interposed therebetween. The semiconductor element structure may include positive and negative electrodes and / or an insulating film. The positive and negative electrodes can be composed of gold, silver, tin, platinum, rhodium, titanium, aluminum, tungsten, palladium, nickel, or an alloy thereof. The insulating film can be made of an oxide or nitride of at least one element selected from the group consisting of silicon, titanium, zirconium, niobium, tantalum, and aluminum. The emission peak wavelength of the light-emitting element can be selected from the ultraviolet region to the infrared region depending on the semiconductor material and its mixed crystal ratio. As the semiconductor material, it is preferable to use a nitride semiconductor, which is a material capable of emitting light with a short wavelength that can efficiently excite the wavelength conversion substance. The nitride semiconductor is mainly represented by a general formula In _x Al _y Ga _1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). The light emission peak wavelength of the light emitting element is preferably 400 nm or more and 530 nm or less, more preferably 420 nm or more and 490 nm or less, and more preferably 450 nm or more and 475 nm or less, from the viewpoints of light emission efficiency, excitation of the wavelength conversion substance, color rendering properties and color reproducibility. Even more preferable. In addition, an InAlGaAs-based semiconductor, an InAlGaP-based semiconductor, zinc sulfide, zinc selenide, silicon carbide, or the like can also be used.

  The substrate of the light emitting element is a crystal growth substrate capable of mainly growing a semiconductor crystal constituting the semiconductor element structure, but may be a bonding substrate bonded to a semiconductor element structure separated from the crystal growth substrate. Since the substrate has a light-transmitting property, it is easy to adopt flip chip mounting, and it is easy to increase the light extraction efficiency. Examples of the substrate include sapphire, spinel, gallium nitride, aluminum nitride, silicon, silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, zinc sulfide, zinc oxide, zinc selenide, diamond and the like. Of these, sapphire is preferable. The thickness of the substrate can be appropriately selected, and is, for example, 0.02 mm or more and 1 mm or less, and is preferably 0.05 mm or more and 0.3 mm or less in terms of the strength of the substrate and / or the thickness of the light emitting device.

(Adhesive member 60)
The adhesive member is a member that has translucency and guides light from the light emitting element to the light transmitting member by bonding the light emitting element and the light transmitting member. Examples of the base material of the adhesive member include silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, diallyl phthalate resin, and modified resins thereof. Of these, silicone resins and modified silicone resins are preferred because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. Moreover, the base material of the adhesive member may contain the same filler as the base material of the above-described light transmitting member.

(External connection terminal 70)
The external connection terminal may be a protruding electrode or a lead electrode. The external connection terminal may also serve as the positive and negative electrodes of the light emitting element. Examples of the protruding electrode include a bump or a pillar. An example of the lead electrode is an individual lead frame. The external connection terminal can be composed of a small piece of metal or alloy. Specific examples include gold, silver, copper, iron, tin, platinum, zinc, nickel, aluminum, tungsten, and alloys thereof. Especially, since copper is excellent in thermal conductivity and relatively inexpensive, copper or a copper alloy is particularly suitable. Gold or a gold alloy is also preferable because it is chemically stable and has a property of being less susceptible to surface oxidation and bonding. The external connection terminal can be formed by a plating method, a stud method, or the like. The external connection terminal may have a coating such as gold or silver on the surface from the viewpoint of solderability.

  Examples according to the present invention will be described in detail below. Needless to say, the present invention is not limited to the following examples.

  The light emitting device of the embodiment has the structure of the light emitting device 100 of the example shown in FIGS. 1A and 1B, and is a rectangular parallelepiped top-emitting CSP type LED having a width of 1.7 mm, a height of 1.7 mm, and a thickness of 0.38 mm Device.

  The first light reflecting member 10 covers the entire side periphery of the light transmitting member 30, and the second light reflecting member 20 covers the entire side periphery of the light emitting element 50 and the pair of external connection terminals 70, respectively. The first light reflecting member 10 and the second light reflecting member 20 are a cured product of phenyl-methyl silicone resin containing 60 wt% titanium oxide. The first light reflecting member 10 and the second light reflecting member 20 have a width of 1.7 mm, a length of 1.7 mm, and a thickness of 0.19 mm, respectively. The reflecting member 20 is integrated, and the interface between the two members is not observed.

  The light emitting element 50 has a sapphire substrate and a semiconductor element structure in which an n-type layer, an active layer, and a p-type layer of a nitride semiconductor are sequentially stacked, and can emit blue light (emission peak wavelength 445 nm) and has a width of 1 mm. A rectangular parallelepiped LED chip having a vertical width of 1 mm and a thickness of 0.15 mm.

  The light transmitting member 30 is bonded to the front surface of the light emitting element 50, that is, the back surface of the sapphire substrate via an adhesive member 60. The light transmitting member 30 has a rectangular shape when viewed from the front with a maximum width of 1.24 mm and a maximum length of 1.24 mm (four corners are rounded), has a thickness of 0.19 mm, and uses YAG: Ce as the wavelength converting material 40. This is a cured product of phenyl-methylsilicone resin containing 0.4 wt% of a filler of silicon oxide nanoparticles containing a phosphor. The light transmission member 30 includes a first region 30a on the front side and a second region 30b on the rear side. The first region 30a is a square pillar-shaped region (four corners are rounded) having a lateral width of 1.2 mm, a vertical width of 1.2 mm, and a thickness of 0.17 mm. The second region 30b has a rectangular front surface with a horizontal width of 1.2 mm and a vertical width of 1.2 mm, a quadrilateral shape (concave when viewed from the front) with a sectional view radius of 0.02 mm, a lateral width of 1.24 mm, and a vertical width. It is a frustum shape having a rear surface of a rectangular shape in plan view of 1.24 mm. The side surface of the first region 30a and the side surface of the second region 30b are smoothly continuous. The wavelength converting substance 40 exists in the first region 30a, does not substantially exist in the second region 30b, and is further unevenly distributed on the front side in the first region 30a. The front surface of the light transmitting member 30, that is, the front surface of the first region 30a and the front surface of the first light reflecting member 10 are substantially the same surface, and constitute the front surface of the light emitting device. The adhesive member 60 is a phenyl-methyl silicone resin (the same resin as the light transmitting member 30) containing 2 wt% of a filler of silicon oxide nanoparticles. The adhesive member 60 covers the front surface of the light emitting element 50 and a part of the front side of each side surface. The adhesive member 60 is located inside the outline of the first region 30a in front view.

  A pair of external connection terminals 70 are connected to the positive and negative electrodes on the rear surface of the light emitting element 50. Each of the pair of external connection terminals 70 is a small piece (interval of 0. 30 mm) having a nickel / gold film formed on the surface of a rectangular parallelepiped copper base having a lateral width of 0.33 mm, a longitudinal width of 0.86 mm, and a thickness of 0.04 mm. 2 mm). The rear surfaces of the pair of external connection terminals 70 are exposed from the second light reflecting member 20, respectively. The rear surfaces of the pair of external connection terminals 70 and the rear surface of the second light reflecting member 20 are substantially the same surface, and constitute the rear surface of the light emitting device.

The light emitting device of this example is manufactured as follows.
(First step)
The first light reflecting member 10 having a plurality of holes 10p is formed on the plate-like jig 90 using a transfer molding machine. The first mold 80, which is a lower mold, is made of stainless steel, and has a rectangular base 83 in plan view with a width of 70 mm, a length of 55 mm, and a thickness of 8.8 mm, and a plurality of protrusions 85 protruding from the base 83. ,have. A plurality of protrusions 85 are formed in the horizontal direction with a center-to-center distance of 1.75 mm and 19 in the vertical direction with a center-to-center distance of 2.43 mm. Each of the protrusions 85 is formed by cutting using an end mill, and includes a columnar portion 85a and a frustum-shaped portion 85b continuous from the columnar portion 85a to the base body 83. The columnar portion 85a is a square columnar portion (four corners are rounded) having a horizontal width of 1.2 mm, a vertical width of 1.2 mm, and a thickness of 0.18 mm. The frustum-shaped portion 85 b is a frustum-shaped portion having a quarter-circular shape (concave when viewed from the outside) having a radius of 0.02 mm in cross-sectional view that is smoothly continuous from the columnar portion 85 a to the base body 83. The second mold 82 which is an upper mold is a flat plate made of stainless steel. The plate-like jig 90 is a plate made of stainless steel having a rectangular shape in plan view with a width of 90 mm, a length of 60 mm, and a thickness of 1 mm. There are 52 pieces at a distance of 1.325 mm and 20 pieces at a center distance of 2.43 mm in the vertical direction.

(Second step)
The liquid material (30) of the light transmitting member is injected into each hole 10p of the first light reflecting member 10 by using a dispenser, and the wavelength conversion substance 40 is forcibly used by the centrifugal separator to the first space 10pa side. And then cured by heating in an oven.

(Third step)
The front surface side of the light emitting element 50 in which the liquid material (60) of the adhesive member is applied onto the main surface of each light transmitting member 30 on the second region 30b side by pin transfer, and the external connection terminals 70 are formed on the rear surface side by plating. And the liquid material (60) of the adhesive member is cured by heating in an oven.

(4th process)
Using the compression molding machine, the second light reflecting member 20 is formed so that all the light emitting elements 50, the adhesive members 60, and the external connection terminals 70 are completely embedded on the first light reflecting member 10. Thereafter, the excessively formed second light reflecting member 20 is removed by grinding, and the surface of each external connection terminal 70 is exposed. Moreover, the 1st light reflection member 10 is removed from the plate-shaped jig | tool 90, and the convex part formed in the through-hole 90h is removed by grinding. Thereby, a small amount of the first region 30a of the light transmitting member is removed. Finally, using a dicing device, the first light reflecting member 10 and the second light reflecting member 20 between the light emitting elements 50 are cut to separate the light emitting device 100 into individual pieces.

  The light emitting device of the example configured as described above and the manufacturing method thereof can achieve the same effects as the light emitting device 100 of the embodiment and the manufacturing method thereof.

  A light emitting device according to an embodiment of the present invention includes a backlight device for a liquid crystal display, various lighting fixtures, a large display, various display devices such as advertisements and destination guidance, a projector device, a digital video camera, a facsimile, a copy It can be used for an image reading apparatus in a machine, a scanner or the like.

10 ... 1st light reflection member (10p ... hole (10pa ... 1st space, 10pb ... 2nd space))
20 ... 2nd light reflection member 30 ... Light transmission member (30a ... 1st area | region, 30b ... 2nd area | region, 30r ... recessed part)
DESCRIPTION OF SYMBOLS 40 ... Wavelength converting substance 50 ... Light emitting element 60 ... Adhesive member 70 ... External connection terminal 80 ... Metal mold | die (1st metal mold | die; 83 ... Base | substrate, 85 ... Protrusion (85a ... Columnar part, 85b ... Frustum-shaped part))
82 ... Second mold 90 ... Plate-shaped jig (90h ... Through hole)
100: Light emitting device

Claims (9)

A first step of forming a first light reflecting member having a hole formed by the protrusion, using a mold having a plate-like base and a protrusion protruding from the base;
A second step of forming a light transmitting member in the hole;
A third step of bonding a light emitting element to the light transmissive member,
The manufacturing method of the light-emitting device in which the said protrusion contains a columnar part and the frustum-shaped part which continues to the said base | substrate from the said columnar part.   The manufacturing method of the light-emitting device according to claim 1, wherein in the first step, an outer surface of the frustum-shaped portion is a concave curved surface.   3. The method for manufacturing a light emitting device according to claim 1, wherein in the first step, a plate-shaped jig having a through hole is prepared, and a part of the first light reflecting member is formed in the through hole. The hole includes a first space formed by the columnar portion and a second space formed by the frustum-shaped portion;
The light transmission member includes a first region formed in the first space and a second region formed in the second space;
In the second step, forming a recess in the first region or the second region,
4. The method for manufacturing a light emitting device according to claim 1, wherein in the third step, the light emitting element is bonded in the recess. 5. The hole includes a first space formed by the columnar portion and a second space formed by the frustum-shaped portion;
The light transmission member includes a first region formed in the first space and a second region formed in the second space;
5. The method of manufacturing a light emitting device according to claim 1, wherein, in the third step, the light emitting element is bonded to the second region side of the light transmitting member. The hole includes a first space formed by the columnar portion and a second space formed by the frustum-shaped portion;
The light transmission member includes a first region formed in the first space and a second region formed in the second space;
5. The method for manufacturing a light emitting device according to claim 1, wherein, in the third step, the light emitting element is bonded to the first region side of the light transmitting member. The light transmissive member contains a wavelength converting substance excited by light of the light emitting element;
The manufacturing method of the light-emitting device according to claim 5 or 6, wherein in the second step, the wavelength converting substance is unevenly distributed on the first region side. The light transmissive member contains a wavelength converting substance excited by light of the light emitting element;
The manufacturing method of the light-emitting device according to claim 6, wherein in the second step, the wavelength converting substance is unevenly distributed on the second region side.   The manufacturing method of the light-emitting device according to claim 1, further comprising a fourth step of covering the periphery of the light-emitting element with a second light reflecting member.

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