JP2019057627A - Method of manufacturing light-emitting device - Google Patents

Abstract

To provide a method of manufacturing a light-emitting device, enabling a terminal to be easily exposed, while allowing for suppression of deterioration of protection performance on an electrode formation surface side of an LED die.SOLUTION: The method of manufacturing a light-emitting device includes a step of preparing an LED die 10 comprising: a laminated structure 13 that includes a light emitting surface 13a, an electrode formation surface 13b on the side opposite to the light emitting surface, and a side surface 13c between the light emitting surface and the electrode formation surface; and a convex-shaped electrode 15 arranged in the electrode formation surface 13b. The method of manufacturing a light-emitting device further includes; a step of preparing a releasing sheet 470; a step of coating a part of a side surface 15c of the electrode with the releasing sheet 470 by causing the electrode 15 to deform the releasing sheet 470, and arranging the releasing sheet 470 in such a manner that the releasing sheet 470 separates from the electrode formation surface 13b; a step of arranging a coating member 40 between the releasing sheet 470 and the electrode formation surface 13b, the coating member 40 coating the side surface 13c of the laminated structure; and a step of removing the releasing sheet 470.SELECTED DRAWING: Figure 2E

Description

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

  For example, in Patent Document 1, a step of preparing a die including a protruding electrode and an adhesive sheet including an adhesive layer on the sheet, and a step of sinking the protruding electrode into the adhesive layer so that the bottom surface of the die contacts the adhesive layer. However, a semiconductor light emitting device comprising: a step of arranging a die on the pressure sensitive adhesive sheet; a step of covering the side surface of the die together with the pressure sensitive adhesive sheet with a resin layer; and a step of cutting the resin layer to obtain a separated semiconductor light emitting device. A manufacturing method is described.

JP 2012-256678 A

  In the conventional method for manufacturing a semiconductor light emitting device, since the resin layer is not formed on the bottom surface of the die, the protection performance on the bottom surface side of the die is lowered.

  Therefore, an embodiment of the present invention has an object to provide a method for manufacturing a light emitting device capable of easily exposing a terminal while suppressing a decrease in protection performance on the electrode forming surface side of an LED die.

  A method of manufacturing a light emitting device according to an embodiment of the present invention includes a laminated structure including a light emitting surface and an electrode forming surface opposite to the light emitting surface, a convex electrode disposed on the electrode forming surface, A step of preparing an LED die comprising: a step of preparing a release sheet; a step of deforming the release sheet by the electrode to cover a part of a side surface of the electrode with the release sheet; A step of disposing the release sheet so as to be separated from the formation surface; a step of disposing a covering member that covers the side surface of the laminated structure as well as between the release sheet and the electrode formation surface; And a step of removing the release sheet.

  According to the method for manufacturing a light emitting device of the above embodiment, the terminal can be easily exposed while suppressing a decrease in the protection performance on the electrode forming surface side of the LED die.

1 is a schematic top 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 the light-emitting device shown to FIG. 1A. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing for demonstrating one process in the manufacturing method 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 and positional relationship of members illustrated in the drawings may be exaggerated for the sake of clarity.

  In the embodiment of the present invention, the visible wavelength range is a range of wavelengths from 380 nm to 780 nm, the blue range is a range of wavelengths from 420 nm to 480 nm, the green range is a range of wavelengths from 500 nm to 560 nm, a yellow range The wavelength is longer than 560 nm and not longer than 590 nm, and the red wavelength range is not less than 610 nm and not more than 750 nm.

  In addition, “translucency” in the present specification means that the light transmittance at the emission peak wavelength of the LED die is 60% or more, preferably 70% or more, and 80% or more. Is more preferable. “Light reflectivity” in the present specification means that the light reflectance at the emission peak wavelength of the LED die is 60% or more, preferably 70% or more, and more preferably 80% or more. preferable.

<Embodiment 1>
(Light Emitting Device 100)
1A is a schematic top view of light-emitting device 100 according to Embodiment 1. FIG. FIG. 1B is a schematic cross-sectional view taken along the line AA of the light emitting device 100 shown in FIG. 1A.

  As shown in FIGS. 1A and 1B, the light emitting device 100 of Embodiment 1 includes an LED die 10, a wavelength conversion member 20, a translucent member 30, a covering member 40, and a conductive film 50. The LED die 10 includes a laminated structure 13 and an electrode 15. The laminated structure 13 has a light emitting surface 13a, an electrode forming surface 13b opposite to the light emitting surface 13a, and a side surface 13c between the light emitting surface 13a and the electrode forming surface 13b. The electrode 15 is disposed on the electrode forming surface 13b. The electrode 15 is convex. The wavelength conversion member 20 is disposed above the LED die 10 (on the light emitting surface 13a side). The wavelength conversion member 20 contains a fluorescent material 25. The translucent member 30 connects the LED die 10 and the lower surface of the wavelength conversion member 20. The covering member 40 covers the electrode forming surface 13b of the LED die, the lower surface of the wavelength conversion member 20, and the outer surface of the translucent member 30. A part of the side surface 15 c and the lower surface of the electrode 15 are exposed from the covering member 40. The conductive film 50 is connected to the electrode 15. The conductive film 50 extends on the lower surface of the covering member 40.

(Method for manufacturing light emitting device 100)
2A, 2B, and 2C are schematic cross-sectional views for explaining a first step, a second step, and a third step in the method for manufacturing light-emitting device 100 according to Embodiment 1, respectively. 2D and 2G are schematic cross-sectional views for explaining a fourth step in the method for manufacturing light-emitting device 100 according to Embodiment 1. FIG. 2E and 2F are schematic cross-sectional views for explaining a fifth step in the method for manufacturing light-emitting device 100 according to Embodiment 1. FIG. 2H, 2I, and 2J are schematic cross-sectional views for explaining the sixth step, the seventh step, and the eighth step in the method for manufacturing the light emitting device 100 according to Embodiment 1, respectively.

  The manufacturing method of the light-emitting device 100 of Embodiment 1 includes at least the following first step, second step, fourth step, fifth step, and sixth step. In addition, the manufacturing method of the light-emitting device 100 of Embodiment 1 further includes a third step and a seventh step. Here, an example is shown in which the composite 150 of the light emitting device is manufactured by the first to seventh steps, and the eighth step of dividing the composite 150 of the light emitting device is provided. Thus, if a plurality of light emitting devices are densely manufactured, the working efficiency of each process is good, and the light emitting device 100 can be manufactured with even higher productivity.

(First step)
As shown in FIG. 2A, in the first step, the laminated structure 13 includes a light emitting surface 13a, an electrode forming surface 13b opposite to the light emitting surface 13a, and a side surface 13c between the light emitting surface 13a and the electrode forming surface 13b. And the LED die 10 provided with the electrode 15 disposed on the electrode forming surface 13b. The electrode 15 is convex and has a side surface 15c. In the present embodiment, a plurality of LED dies 10 are prepared. Details of the LED die 10 will be described later.

(Second step)
As shown in FIG. 2B, the second step is a step of preparing a release sheet 470. The base material of the release sheet 470 is preferably a resin in terms of heat resistance, chemical resistance, and the like. In particular, at least the surface of the release sheet 470 is preferably made of a fluorine-based resin or a silicone-based resin from the viewpoint of releasability. In addition, a metal foil, paper, cloth, or the like can be used as the base material of the release sheet 470. The thickness of the release sheet 470 can be selected as appropriate, but it is preferably a thickness that is at least half the thickness of the electrode 15. Thereby, it is easy to insert the electrode 15 while deforming the release sheet 470 along the shape of the electrode 15.

(Third step)
As shown in FIG. 2C, the third step is a step of connecting the wavelength conversion member 20 to the light emitting surface 13 a side of the LED die 10 via the translucent member 30. Specifically, after the liquid material 309 of the translucent member is applied to one main surface of the wavelength conversion member 20 and the LED die 10 is placed with the light emitting surface 13a opposed thereto, the liquid of the translucent member is placed. The material 309 is cured or solidified. At this time, the LED die 10 is pressed, and at least a part of the liquid material 309 of the translucent member is crawled up on the side surface 13c of the laminated structure. As a method for applying the liquid material 309 of the light transmissive member, a dispense method, a transfer method, or the like can be used.

  Here, the wavelength conversion member 20 shows an example obtained by preparing a fluorescent sheet containing the fluorescent material 25 as the wavelength conversion sheet 250 and dividing the wavelength conversion sheet 250 in the eighth step. In addition, what divided | segmented (single piece) such a fluorescent sheet can also be used as the wavelength conversion member 20. FIG. Moreover, in this Embodiment, the wavelength conversion member 20 of the two-layer structure which has the fluorescent layer containing the fluorescent substance 25 and the translucent layer which does not contain fluorescent substance substantially is prepared. The two-layered fluorescent sheet is preferably produced by joining two element sheets. Thereby, it is easy to control the distribution of the fluorescent material 25 in the fluorescent sheet and thus in the wavelength conversion member 20 to a suitable form, and it is easy to prepare the wavelength conversion member 20 with high productivity. In addition, when two element sheets are bonded, the main material of at least one of the two element sheets (preferably both) is not completely cured or solidified. This is preferable from the viewpoint of suppressing distortion in the sheet. Moreover, although the boundary, ie, interface, of the two joined element sheets in the fluorescent sheet may be observed, it is preferable not to be observed from the same viewpoint. The “state that is not completely cured or solidified” is a state in which curing or solidification has progressed to the middle, for example, a state called semi-cured, B-stage, gel, semi-solidified, etc. .

(4th process)
As shown in FIGS. 2D and 2G, in the fourth step, the release sheet 470 is deformed by the electrode 15 so as to cover a part of the side surface 15c of the electrode with the release sheet 470 and to be separated from the electrode forming surface 13b. In this step, the release sheet 470 is disposed on the surface. Specifically, the release sheet 470 is disposed so as to face the electrode forming surface 13 b of the LED die 10 and contact the electrode 15. Thereafter, a pressure is applied to the release sheet 470 and / or the LED die 10 so that a part of the electrode 15 is embedded in the release sheet 470. At this time, workability is good if the release sheet 470 is attached to one of the upper and lower molds of the molding apparatus.

(5th process)
As shown in FIGS. 2E and 2F, the fifth step is a step of disposing the covering member 40 that covers the release sheet 470 and the electrode forming surface 13b as well as the side surface 13c of the laminated structure. Specifically, the liquid material 409 of the covering member is continuously applied between the release sheet 470 and the electrode forming surface 13b and on the side surface 13c of the laminated structure, and is cured or solidified. In the present embodiment, the liquid material 409 of the covering member is applied so as to continuously cover one main surface of the wavelength conversion member 20 and the outer surface of the translucent member 30, and is cured or solidified. Moreover, in this Embodiment, it forms as the integral molding 450 of a coating | coated member by coat | covering several LED die 10 continuously.

  Here, the fifth step can be performed before the fourth step or can be performed after the fourth step. As shown in FIGS. 2D and 2E, it is preferable that the covering member 40 is disposed between the release sheet 470 and the electrode forming surface 13 b after part of the side surface 15 c of the electrode is covered with the release sheet 470. Thereby, since the covering member 40 is filled in a state in which a part of the electrode 15 is embedded in the release sheet 470 and covered, it is possible to perform molding with excellent dimensional accuracy. In this case, transfer molding, injection molding, potting, etc. can be applied. On the other hand, as shown in FIGS. 2F and 2G, the covering member 40 may be disposed between the release sheet 470 and the electrode forming surface 13b before a part of the side surface 15c of the electrode is covered with the release sheet 470. preferable. As a result, it is possible to reduce the stress on the LED die 10 by forming the covering member 40 with a low pressure while part of the electrode 15 is embedded in the release sheet 470. In this case, compression molding, laminate molding, or the like can be applied.

  In addition, before arrange | positioning the release sheet 470, it is preferable to arrange | position the supporting member 490 facing the light emission surface 13a. Thereby, it is easy to install the LED die 10 stably, and it is easy to adjust the amount of penetration of the electrode 15 into the release sheet 470. Moreover, the filling pressure of the liquid material 409 of the covering member can be easily increased, and the covering member 40 can be easily filled between the electrode forming surface 13b of the laminated structure and the release sheet 470. The support member 490 can be, for example, one of the upper and lower molds of the molding apparatus.

(6th process)
As shown in FIG. 2H, the sixth step is a step of removing the release sheet 470. More specifically, the release sheet 470 is peeled off from the cured or solidified covering member 40 (here, the integral molding 450 of the covering member) and the electrode 15 and removed. Further, when the support member 490 is disposed, the support member 490 may also be removed.

(Seventh step)
As shown in FIG. 2I, the seventh step is a step of disposing the conductive film 50 connected to the electrode 15 after removing the release sheet 470. Specifically, the conductive film 50 connected to the electrode 15 is formed on the exposed surface of the covering member 40 (here, the integral molding 450 of the covering member) formed on the electrode forming surface 13b of the laminated structure. In the present embodiment, the continuous conductive film 550 is formed continuously with the electrodes 15 of the plurality of LED dies 10. Since the covering member 40 exists on the electrode forming surface 13b of the laminated structure, the conductive film 50 can be disposed on the covering member 40. The conductive film 50 can further enhance the protection performance of the LED die 10 on the electrode forming surface 13b side. In addition, the conductive film 50 functions as a terminal of the light emitting device 100 and can increase a bonding area when the light emitting device 100 is mounted. The conductive film 50 can be formed by sputtering, plating, vapor deposition, printing, or the like.

(8th step)
As shown in FIG. 2J, the eighth step is a step of dividing the composite 150 of the light emitting device. Specifically, an integral molding 450 (in this embodiment, the wavelength conversion sheet 250 and the continuous conductive film 550) of the covering member between the LED dies 10 at a predetermined position of the composite 150 of the light emitting device is linear or lattice-shaped. The light emitting device 100 is separated into pieces. For example, a dicer, an ultrasonic cutter, a Thomson blade, or the like can be used to cut the composite 150 of the light emitting device. In addition, when manufacturing the light-emitting device 100 separately one by one, this 8th process can be abbreviate | omitted.

  According to the method of manufacturing the light emitting device 100 having the above-described configuration, the covering member 40 is laminated by allowing a part of the electrode 15 to be embedded in the release sheet 470 during the forming process of the covering member 40. A structure in which a part of the electrode 15 is exposed while covering the electrode forming surface 13b of the structure can be easily formed. Therefore, it is possible to easily expose the terminal while suppressing a decrease in the protection performance on the electrode forming surface 13b side of the LED die 10.

  Hereinafter, each component of the light emitting device according to the embodiment of the present invention will be described.

(LED die 10)
The LED die has a stacked structure including a light emitting element structure and an electrode for supplying power to the stacked structure. The shape of the LED die viewed from above is preferably a triangle, a quadrangle, or a hexagon, and more preferably a square or a rectangle that is long in one direction. The side surface of the LED die or its laminated structure may be perpendicular to the upper surface or the lower surface (light emitting surface or electrode forming surface), or may be inclined inward or outward. The number of LED dies mounted on one light emitting device may be one or plural. The plurality of LED dies can be connected in series or in parallel.

(Laminated structure 13)
The stacked structure includes at least a semiconductor stacked body and may further include a substrate.

(Semiconductor laminate)
The semiconductor laminate preferably includes at least an n-type semiconductor layer and a p-type semiconductor layer, with an active layer interposed therebetween. As the semiconductor material, it is preferable to use a nitride semiconductor capable of efficiently emitting short-wavelength light that easily excites a fluorescent 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). In addition, zinc sulfide, zinc selenide, silicon carbide, or the like can be used. The emission peak wavelength of the LED die is preferably in the blue region, and more preferably in the range of 450 nm to 475 nm, from the viewpoints of light emission efficiency, the excitation of the fluorescent substance and the color mixing relationship with the light emission. The thickness of the semiconductor laminate can be selected as appropriate, but it is preferably 1 μm or more and 10 μm or less, and more preferably 3 μm or more and 10 μm or less in terms of luminous efficiency, crystallinity, and the like.

(substrate)
The substrate is preferably a crystal growth substrate capable of growing a semiconductor crystal, but may be a bonding substrate that is separately bonded to a semiconductor laminate separated from the crystal growth substrate. Since the substrate has translucency, it is easy to adopt a flip chip type and to improve the light extraction efficiency. As the substrate, one of sapphire, gallium nitride, aluminum nitride, silicon, silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, zinc sulfide, zinc selenide, and glass can be used. Of these, sapphire is preferable because it is excellent in translucency and easily available as a nitride semiconductor crystal growth substrate at a relatively low cost. Further, gallium nitride is suitable as a substrate for crystal growth of a nitride semiconductor, and is preferable in terms of relatively high thermal conductivity. The thickness of the substrate can be selected as appropriate, but it is preferably 50 μm or more and 500 μm or less, and more preferably 80 μm or more and 300 μm or less in terms of light extraction efficiency, mechanical strength, and the like.

(Electrode 15)
In addition to the positive and negative electrodes formed in contact with the semiconductor layer, the electrodes may include bumps, pillars, lead electrodes (separated lead frames) and the like that are separately provided by connecting to the positive and negative electrodes. The electrode may be composed of a metal or alloy film and / or pieces. Specifically, at least one of gold, silver, copper, iron, tin, platinum, zinc, rhodium, titanium, nickel, palladium, aluminum, tungsten, chromium, molybdenum, and alloys thereof can be used. Especially, it is especially preferable that an electrode is excellent in thermal conductivity and contains the copper or copper alloy which is comparatively cheap. The electrode preferably has a gold or silver film on the surface from the viewpoint of solderability. The electrode can be formed by plating, sputtering, vapor deposition, printing, or the like. The thickness of the electrode can be selected as appropriate, but it is preferably 1 μm or more and 150 μm or less, and more preferably 20 μm or more and 100 μm or less in terms of mountability of the light emitting device.

(Wavelength conversion member 20)
The wavelength conversion member has a function of transmitting the light of the LED die and the fluorescent substance to the outside of the apparatus while protecting the LED die from the outside air and external force together with the light transmitting member and the covering member. The wavelength conversion member has at least a translucent main material, and further contains a fluorescent substance in the main material. The top view shape of the wavelength conversion member is preferably larger than the LED die and mathematically similar to the top view shape of the LED die in terms of luminous intensity distribution, chromaticity distribution, and the like. If the upper surface and / or lower surface of the wavelength conversion member is a flat surface, the productivity is good, and if it is a surface having irregularities or a curved surface, the light extraction efficiency can be increased. The wavelength conversion member may be composed of a single layer or a laminate of a plurality of layers in the thickness direction. When the wavelength conversion member is composed of a laminate, different types of main materials may be used for each layer, or different types of fluorescent materials may be contained in each layer. In addition, since the outermost layer is a layer that does not substantially contain a fluorescent material, deterioration of the fluorescent material due to outside air or the like can be suppressed. The thickness of the wavelength conversion member can be appropriately selected, but is preferably 50 μm or more and 500 μm or less, and more preferably 80 μm or more and 300 μm or less in terms of light extraction efficiency, phosphor content, and the like.

(Main material of wavelength conversion member)
As the main material of the wavelength conversion member, at least one of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, modified resins thereof, and glass can be used. Especially, a silicone resin or its modified resin is preferable at the point which is 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. In particular, heat resistance and gas barrier properties are enhanced by including a phenyl group. The “modified resin” in this specification includes a hybrid resin.

(Fluorescent substance 25)
The fluorescent material absorbs at least part of light (primary light) emitted from the LED die and emits light (secondary light) having a wavelength different from that of the primary light. The emission peak wavelength of the fluorescent substance emitting green light is preferably in the range of 520 nm or more and 560 nm or less from the viewpoints of light emission efficiency and color mixing relationship with light from other light sources. Specifically, examples of fluorescent substances that emit green light include yttrium, aluminum, and 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 fluorescent material (e.g., _{Tb 3 (Al, Ga) 5} O 12: Ce) phosphor, silicate-based phosphors (e.g. (Ba, _{Sr) 2} SiO _4: Eu), chloro silicate-based phosphor (e.g. _{Ca 8 Mg (SiO 4) 4} C l2: Eu), β -sialon-based phosphor (e.g. _{Si 6-z Al z O z} N 8-z: Eu (0 <Z <4.2)), SGS-based phosphors (for example, SrGa ₂ S ₄ : Eu), and the like. As a fluorescent substance that emits yellow light, an α-sialon-based phosphor (for example, Mz (Si, Al) ₁₂ (O, N) ₁₆ (where 0 <z ≦ 2 and M is Li, Mg, Ca, Y, and Lanthanide elements excluding La and Ce), etc. In addition, among the phosphors that emit green light, there are phosphors that emit yellow light. By replacing the portion with Gd, the emission peak wavelength can be shifted to the longer wavelength side, and yellow emission is possible, and some of these fluorescent substances are capable of emitting orange light. The emission peak wavelength of the fluorescent material is preferably in the range of 620 nm or more and 670 nm or less from the viewpoints of luminous efficiency, color mixing relationship with light from other light sources, etc. Specifically, the fluorescent material emits red light. The nitrogen-containing calcium aluminosilicate (CASN or SCASN) phosphor (e.g. _{(Sr, Ca) AlSiN 3:} Eu). , And the like In addition, manganese activated fluoride phosphor (general formula (I) A ₂ A phosphor represented by [M _1-a Mn _a F ₆ ] (in the general formula (I), A is selected from the group consisting of K, Li, Na, Rb, Cs and NH _4). And M is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and a satisfies 0 <a <0.2)). A typical example of the manganese-activated fluoride phosphor is a manganese-activated potassium fluorosilicate phosphor (for example, K ₂ SiF ₆ : Mn), which is a single type of the above specific examples. Or 2 It can be used in combination of at least.

(Translucent member 30)
The translucent member has translucency and can guide the light of the LED die to the wavelength conversion member, and can also bond the LED die and the wavelength conversion member. From the viewpoint of light extraction efficiency, the outer surface of the translucent member, that is, the interface with the covering member, is preferably inclined or curved with respect to the side surface of the laminated structure and the lower surface of the wavelength conversion member. As the main material of the translucent member, at least one of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, modified resins thereof, and glass can be used. Especially, a silicone resin or its modified resin is preferable at the point which is 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. In particular, heat resistance and gas barrier properties are enhanced by including a phenyl group. In addition, the translucent member may contain various fillers in the main material. As the filler, the same filler as that of the following covering member can be used.

(Coating member 40)
As the main material of the covering member, at least one of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, modified resins thereof, and glass can be used. Especially, a silicone resin or its modified resin is preferable at the point which is 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. In particular, heat resistance and gas barrier properties are enhanced by including a phenyl group.

(Filler)
The covering member preferably contains a filler. By including a filler in the covering member, for example, adjusting various physical properties of the covering member according to the purpose, such as increasing the light reflectance, thermal conductivity, or mechanical strength, or decreasing the thermal expansion coefficient. Can do. Therefore, it is easy to maintain high protection performance on the electrode forming surface side of the LED die. The filler may be organic but is preferably inorganic. Inorganic substances are superior in light resistance and heat resistance compared to organic substances and are not easily deteriorated. Moreover, if it is an inorganic substance, it will be easy to adjust the thermal conductivity, thermal expansion coefficient, etc. of a coating | coated member. As a specific inorganic substance, at least one of silicon oxide, titanium oxide, magnesium oxide, zinc oxide, aluminum oxide, zirconium oxide, calcium carbonate, and barium sulfate is preferable. Of these, silicon oxide, titanium oxide, and zirconium oxide are preferable because they are relatively inexpensive and easily available. Magnesium oxide, zinc oxide, and aluminum oxide are preferable from the viewpoint of thermal conductivity. If it is an organic substance, there exists an advantage which can adjust an optical characteristic by copolymerization. Specific organic materials include polymethacrylic acid ester and its copolymer, polyacrylic acid ester and its copolymer, cross-linked polymethacrylic acid ester, cross-linked polyacrylic acid ester, polystyrene and its copolymer, cross-linked polystyrene, silicone Resins and their modified resins are preferred. A filler can be used individually by 1 type of these or in combination of 2 or more types of these. Although content of the filler in a coating | coated member can be selected suitably, it is preferable that it is 1 to 100 weight part, and it is more preferable that it is 5 to 50 weight part. The “parts by weight” represents the weight (g) of the particles blended with respect to 100 g of the main material. The shape of the filler can be selected as appropriate and may be crushed (indeterminate), but a spherical shape is preferred from the viewpoints of filling properties and suppression of aggregation.

(White pigment)
The covering member is preferably white in terms of light extraction efficiency. Therefore, the covering member preferably contains a white pigment. 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. Of these, titanium oxide is preferable because it has excellent light reflectivity and is easily available at a relatively low cost. The content of the white pigment in the covering member can be appropriately selected, but is preferably 20 parts by weight or more and 300 parts by weight or less, and preferably 50 parts by weight or more and 200 parts by weight in terms of light reflectivity and viscosity at the time of liquid material. It is more preferable that the amount is not more than parts.

(Conductive film 50)
The conductive film can be formed of a single layer film or a multilayer film of metal or alloy. Specifically, at least one of gold, silver, copper, iron, tin, platinum, zinc, rhodium, titanium, nickel, palladium, aluminum, tungsten, chromium, molybdenum, and alloys thereof can be used. The conductive film preferably has gold or silver on the surface from the viewpoint of solder bonding.

  As described above, the light emitting device of Embodiment 1 is an example of a top emission type (top view) type. However, a side emission type (side view) type may be used depending on the arrangement relationship of terminals with respect to the main emission direction. The mounting direction of the top emission type light emitting device is substantially parallel to the main light emitting direction and in the opposite direction. For example, the mounting direction of the light-emitting device of Embodiment 1 is downward. On the other hand, the mounting direction of the side-emitting type light emitting device is substantially perpendicular to the main light emitting direction.

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.
<Example 1>
The light-emitting device of Example 1 has the structure of the light-emitting device 100 of the example shown in FIGS. 1A and 1B, and is a rectangular parallelepiped top-surface light emitting and surface-mounting type having a width of 1.7 mm, a depth of 1.7 mm, and a thickness of about 0.3 mm. LED device. The LED die 10 is a square die having a width of 1.0 mm, a depth of 1.0 mm, and a thickness of 0.15 mm, as viewed from above, capable of emitting blue light with an emission peak wavelength of 455 nm. The LED die 10 has a laminated structure 13 in which a nitride semiconductor n-type semiconductor layer, an active layer, and a p-type semiconductor layer are sequentially laminated on a sapphire substrate. A pair of electrodes 15 serving as a positive electrode and a negative electrode are connected to the electrode forming surface 13b of the laminated structure. The pair of electrodes 15 are convex with respect to the electrode forming surface 13b. The pair of electrodes 15 is composed of a multilayer film of titanium / nickel / gold / copper and a small piece of copper having a thickness of 50 μm. The wavelength conversion member 20 is connected to the light emitting surface 13a side of the laminated structure via the light transmitting member 30. The wavelength conversion member 20 is a small piece of phosphor-containing resin having a width of 1.7 mm, a depth of 1.7 mm, and a thickness of 0.15 mm in a square shape when viewed from above. The centers and orientations of the LED die 10 and the wavelength conversion member 20 in the top view match (however, manufacturing errors are included). The wavelength conversion member 20 is composed of the following two layers: a fluorescent layer (lower layer) and a light transmitting layer (upper layer). However, the boundary between the fluorescent layer and the light transmitting layer is not observed. The fluorescent layer is a cured product of a phenyl-methyl silicone resin containing a TAG fluorescent substance and a YAG fluorescent substance as the fluorescent substance 25. The light transmitting layer is a cured product of phenyl-methyl silicone resin. The translucent member 30 covers the light emitting surface 13 a and the four side surfaces 13 c of the laminated structure and the lower surface of the wavelength conversion member 20. The outer surface of the translucent member 30 is inclined or curved with respect to the side surface 13 c of the laminated structure and the lower surface of the wavelength conversion member 20. The translucent member 30 is a cured product of phenyl-methyl silicone resin. The covering member 40 covers the outer surface of the translucent member 30 on the side of the laminated structure 13 and covers the region excluding the pair of electrodes 15 on the electrode forming surface 13b of the laminated structure 13 below the laminated structure 13. doing. If the translucent member 30 does not cover a part (lower part) of the side surface 13c of the laminated structure, the covering member 40 covers a part (lower part) of the side surface 13c of the laminated structure. The covering member 40 covers a part of the side surface 15c of the electrode. The covering member 40 is a cured product of phenyl-methyl silicone resin containing 10 parts by weight of silicon oxide spherical particles having an average particle diameter of 5 to 50 nm as filler and 150 parts by weight of titanium oxide as white pigment. A portion having a thickness of 20 μm on the lower side of the pair of electrodes 15 is exposed from the covering member 40. A conductive film 50 is connected to each of the pair of electrodes 15. The conductive film 50 extends on the lower surface of the covering member 40. The conductive film 50 is a nickel / gold film. The thickness of the conductive film 50 is 0.1 μm.

  The light emitting device of Example 1 is manufactured by manufacturing a light emitting device composite 150 and dividing the light emitting device composite 150 with a dicing device as follows. First, the first element sheet having a thickness of 100 μm serving as the fluorescent layer and the second element sheet having a thickness of 50 μm serving as the translucent layer are pressure-bonded and completely cured, whereby the fluorescence as the wavelength conversion sheet 250 is obtained. A sheet is produced. Next, the wavelength conversion sheet 250 is placed on a polyimide tape with the fluorescent layer side facing up. Next, a liquid material 309 of a translucent member is applied to the upper surface of the wavelength conversion sheet 250 at a predetermined interval by pin transfer. Next, the sapphire substrate side of the LED die 10 in which the small pieces of copper having a thickness of 50 μm are respectively connected to the positive and negative electrodes to constitute the electrode 15 is placed on the liquid material 309 of each translucent member applied to the wavelength conversion sheet 250. Place. Further, the LED die 10 is pushed in, and the liquid material 309 of the translucent member is crawled up on the four side surfaces of the LED die 10. Then, the liquid material 309 of the translucent member is cured in an oven to obtain the translucent member 30. Next, an upper mold in which a tape on which the LED die 10 or the like is placed is placed on a lower mold (support member 490) of a transfer molding apparatus, and a release sheet 470 made of a fluororesin having a thickness of 50 μm is attached. Close. At this time, the upper part of the small piece of copper constituting the electrode 15 of each LED die 10 is made to dig into the release sheet 470 by 20 μm. Then, the liquid material 409 of the covering member is filled in the cavities of the upper and lower molds and cured. Thereafter, a nickel / gold film having a thickness of 0.1 μm is formed on the integral molding 450 of the covering member and each piece of copper with a sputtering apparatus to form a continuous conductive film 550. Finally, the composite 150 of the light emitting device obtained as described above is cut into a lattice shape with a dicer.

  The manufacturing method of the light emitting device of Example 1 configured as described above can achieve the same effects as the manufacturing method of the light emitting device 100 of Embodiment 1.

  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, destination guides, 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.

DESCRIPTION OF SYMBOLS 10 LED die 13 Laminated structure 13a Light emission surface 13b Electrode formation surface 13c Side surface 15 Electrode 15c Side surface 20 Wavelength conversion member 25 Fluorescent substance 30 Translucent member 40 Cover member 50 Conductive film 100 Light emitting device 150 Light emitting device complex 250 Wavelength conversion sheet 309 Liquid material of translucent member 409 Liquid material of covering member 450 Integral molded product of covering member 470 Release sheet 490 Support member 550 Continuous conductive film

Claims (10)

A laminated structure comprising a light emitting surface, an electrode forming surface opposite to the light emitting surface, a side surface between the light emitting surface and the electrode forming surface, and a convex electrode disposed on the electrode forming surface; Preparing an LED die comprising:
A step of preparing a release sheet;
The step of deforming the release sheet with the electrode to cover a part of the side surface of the electrode with the release sheet and disposing the release sheet so as to be separated from the electrode forming surface;
A step of disposing a covering member that covers the side surface of the laminated structure as well as between the release sheet and the electrode forming surface;
And a step of removing the release sheet.   The manufacturing method of the light-emitting device according to claim 1, wherein the covering member is disposed between the release sheet and the electrode forming surface after a part of a side surface of the electrode is covered with the release sheet.   The manufacturing method of the light-emitting device according to claim 1, wherein the covering member is disposed between the release sheet and the electrode forming surface before a part of a side surface of the electrode is covered with the release sheet.   The manufacturing method of the light-emitting device according to any one of claims 1 to 3, wherein a base material of the release sheet is a resin.   The thickness of the said release sheet is a manufacturing method of the light-emitting device as described in any one of Claim 1 to 4 which is a thickness more than half of the thickness of the said electrode.   The method for manufacturing a light-emitting device according to claim 1, wherein the covering member contains a filler.   The method for manufacturing a light emitting device according to claim 6, wherein the filler is an inorganic substance.   The method for manufacturing a light emitting device according to claim 1, wherein the covering member contains a white pigment.   The method for manufacturing a light-emitting device according to claim 1, further comprising a step of disposing a conductive film connected to the electrode after removing the release sheet.   The method for manufacturing a light emitting device according to any one of claims 1 to 9, wherein a support member is disposed to face the light emitting surface before the release sheet is disposed.

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