JP6669292B2 - Light emitting device and method of manufacturing the same - Google Patents

Description

  The present invention relates to a light emitting device having a light emitting element and a method for manufacturing the same.

  A light emitting device using a light emitting element and a phosphor is known. For example, a light emitting device having a transparent resin covering a side portion of a semiconductor light emitting element, a white reflecting member covering the transparent resin, and a phosphor member covering the transparent resin is known (for example, Patent Documents 1 and 2).

JP 2012-227470 A JP 2013-012545 A

  In such a light-emitting device, a light-emitting device in which emission color unevenness is unlikely to occur is required.

Embodiments of the present invention include the following configurations.
A bonding step of bonding the first surface of the wavelength conversion member and the first surface of the diffusion member having a thickness of about half the thickness of the wavelength conversion member, and opposing the first surface of the diffusion member. A first light emitting element arranging step of arranging a light emitting element on a second surface of the diffusing member, which is a surface to be diffused; A first light-transmissive member forming step, a first cover member forming step of covering an outer surface of the light-transmissive member and a part of the second surface of the diffusion member with a cover member, and the wavelength conversion member. And a first cutting step of cutting the diffusion member and the covering member.
The embodiment of the present invention also includes the following configuration.
A second light-emitting element disposing step of disposing light-emitting elements on a first surface of a sheet; and a second light-transmitting member covering a side surface of the light-emitting element and a part of the first surface of the sheet with a light-transmitting member. A member forming step, a second covering member forming step of covering the outer surface of the translucent member and a part of the first surface of the sheet with a covering member, and a peeling step of peeling the sheet from the light emitting element. Forming a diffusion member and a wavelength conversion member in this order on the light emitting element and the translucent member, wherein the thickness of the diffusion member is about half the thickness of the wavelength conversion member. A method for manufacturing a light emitting device, comprising: a forming step; and a second cutting step of cutting the covering member.
Further, the light emitting device manufactured with the above configuration includes the following configuration.
A first surface, a second surface facing the first surface, a plurality of side surfaces between the first surface and the second surface, and a pair of electrodes on the second surface side A light-transmitting member that covers at least a part of at least one side surface, a coating member that covers an outer surface of the light-transmitting member so as to expose a pair of electrodes, and a light-transmitting member that covers the first surface of the light-emitting element. A light emitting device comprising: a diffusion member that covers an optical member; and a wavelength conversion member that covers the diffusion member.

  According to the above-described solution, a light-emitting device with reduced emission color unevenness and a method for manufacturing the same can be provided.

FIG. 1A is a schematic plan view of the light emitting device according to the first embodiment. FIG. 1B is a schematic cross-sectional view taken along the line AA of FIG. 2A to 2E are schematic cross-sectional views illustrating a method for manufacturing the light emitting device according to the first embodiment. FIG. 3A is a schematic plan view of the light emitting device according to the second embodiment. FIG. 3B is a schematic cross-sectional view taken along the line BB of FIG. 4A to 4F are schematic cross-sectional views illustrating a method for manufacturing the light emitting device according to the second embodiment. FIG. 5 is a schematic plan view of the light emitting device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, a term indicating a specific direction or position (for example, “up”, “down”, “right”, “left”, and another term including those terms) is used as necessary. . The use of these terms is for facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meaning of the terms. In addition, portions denoted by the same reference numerals in a plurality of drawings indicate the same portions or members.

<First Embodiment>
The light-emitting device 10 according to the present embodiment shown in FIGS. 1A and 1B includes a light-emitting element 20, a light-transmitting member 30 provided on the side surface 23 of the light-emitting element 20, and a light-transmitting member 30. And a covering member 40 that covers the outer surface 33. The light emitting device 10 can include a diffusion member 50 on the first surface (upper surface) 11 side functioning as a light emitting surface, and a wavelength conversion member 60 on the first surface (upper surface) 51 side of the diffusion member.

  FIG. 1B is a schematic cross-sectional view taken along line AA of FIG. 1 (a line orthogonal to a pair of opposed side surfaces 23 of the light emitting element 20). As shown in FIG. 1B, the light emitting element 20 can include a light transmitting substrate 27 and a semiconductor stacked body 28 formed on the lower surface side of the light transmitting substrate 27. The light-emitting element 20 includes a first surface (upper surface) 21 on the light-transmitting substrate 27 side, a second surface (lower surface) 22 on the semiconductor stacked body 28 side facing the first surface 21, and a first surface. A plurality of side surfaces 23 are provided between the first surface 21 and the second surface 22. The light emitted by the light emitting element 20 passes through the light transmitting substrate 27 from the semiconductor stack 28 or from the semiconductor stack 28 to the side surface 23 of the light emitting element 20 and the light transmitting member 30, the diffusion member 50, and the wavelength conversion member 60. Through the light-emitting device 10 to the first surface 11 side.

  On the second surface 22 of the light emitting element 20 (on the side of the semiconductor laminate 28 in FIG. 1B), a pair of electrodes 251 and 252 for supplying electricity to the light emitting element 20 are provided. Note that, in this specification, the “second surface 22” of the light-emitting element 20 refers to the surface of the light-emitting element 20 that does not include the electrodes 251 and 252. In the present embodiment, the second surface 22 coincides with the lower surface of the semiconductor stack 28.

  Each of the two electrodes 251 and 252 forming a pair of electrodes can have an arbitrary shape. For example, the electrodes 251 and 252 can be rectangular shapes that extend in one direction when viewed from the second surface 12 side of the light emitting device 10. Note that the electrodes 251 and 252 need not have the same shape. The two electrodes 251 and 252 can be arbitrarily arranged as long as they are separated from each other.

  The translucent member 30 is provided so as to cover at least the light emitting layer on the side surface 23 of the light emitting element 20, and guides light emitted from the side surface 23 toward the first surface 11 of the light emitting device 10. . That is, before the light reaching the side surface 23 of the light emitting element 20 is reflected by the side surface 23 and attenuated in the light emitting element 20, the light can be extracted to the outside of the light emitting element 20 through the light transmitting member 30. By providing the translucent member 30, light loss can be suppressed, and the light extraction efficiency of the light emitting device 10 can be improved.

  In particular, when the side surface 23 of the light emitting element 20 is inclined with respect to the second surface 22, for example, when the angle between the side surface 23 of the light emitting element 20 and the second surface 22 is an acute angle, The effect of the optical member 30 becomes significant. For example, in the manufacturing process of the light emitting element 20, when the light emitting element 20 is divided into individual pieces by cleavage, the side surface 23 of the light emitting element 20 may not be perpendicular to the second surface 22 in some cases. Generally, in a cross section taken along the line AA in FIG. 1 (FIG. 1B), the light emitting element 20 has a parallelogram shape. In other words, the first surface 21 and the second surface 22 are parallel, the two opposing side surfaces 23 are parallel, and each side surface 23 has a light emission inclined with respect to the first surface 21 and the second surface 22. It becomes the element 20. Since the angle between the one side surface 23 and the second surface 22 becomes obtuse, the light reflected on the one side surface 23 is directed toward the first surface 21 of the light emitting element 20 by the light of the light emitting device 10. Can be taken out. However, the angle formed between the other side surface 23 and the second surface 22 is acute, so that the light reflected on the other side surface 23 is directed toward the second surface 22 in the light emitting element 20. Can decay.

  By covering the other side surface 23 with the translucent member 30, the light reaching the other side surface 23 can be extracted to the outside of the light emitting device 10 through the translucent member 30. In addition to cleaving the light-emitting element into individual pieces, for example, after an n-type semiconductor layer, a light-emitting layer (active layer), and a p-type semiconductor layer are stacked on a sapphire substrate, a part of the p-type semiconductor layer is formed. In some cases, part of the light emitting layer is etched to expose part of the n-type semiconductor layer or part of the sapphire substrate. In such a case, the side surfaces of the p-type semiconductor layer, the active layer, the n-type semiconductor layer, and the sapphire substrate may be inclined depending on the etching conditions and the like. Even in such a case, by covering the inclined side surface with the light transmitting member 30, light can be extracted to the outside of the light emitting device through the light transmitting member 30.

The first surface of the light emitting element 20 and the diffusion member 50 may be bonded by an adhesive 35. The adhesive 35 is preferably translucent, and examples of the material include the same material as the translucent member 30 or a different material. Further, an adhesive member may be provided not only between the light emitting element and the diffusion member but also between the translucent member and the diffusion member. In this case, for example, as described later, an adhesive member is disposed on a sheet-like diffusion member, and when the light emitting element 20 is placed thereon, the adhesive member is protruded outside the side surface of the light emitting element 20. Can be provided.
At this time, the adhesive may be provided so as to be in contact with the side surface of the light emitting element. By providing the translucent member 30 after providing such an adhesive member, a region where the adhesive member is in contact and a region where the translucent member is in contact exist on the side surface of the light emitting element. In other words, the adhesive member and the translucent member are formed on the side surface of the light emitting element so as to overlap.

  The shape of the diffusion member 50 can be a flat surface, a convex shape, a concave shape, or a shape having a plurality of irregularities. Further, the shape in a top view can be a square, a circle, an ellipse, or the like. In the case of the convex shape, the height, that is, the height from the first surface 21 of the light emitting element to the second surface 62 of the wavelength conversion member can be within 80 μm. However, the thickness of the wavelength conversion member may vary depending on the composition and amount of the phosphor used for the wavelength conversion member, and for example, the thickness of the diffusion member 50 may be about half the thickness of the wavelength conversion member 60. Can be.

  The pair of electrodes 251 and 252 of the light emitting element 20 are exposed from the covering member 40 and are exposed on the second surface (lower surface) 12 of the light emitting device 10. Thus, the external electrodes provided on the substrate or the like on which the light emitting element 20 is mounted can be connected to the electrodes 251 and 252 of the light emitting element 20. In addition, it is preferable that the light emitting element 20 be covered with the covering member 40 in order to protect the light emitting element 20 from the external environment, except for the part where the electrodes 251 and 252 are provided on the second surface 22.

  When the covering member 40 covers the second surface 22 of the light emitting element 20, the electrodes 251 and 252 formed on the second surface 22 of the light emitting element 20 are exposed on the surface of the light emitting device 10 (the second surface 12). To do. For example, the side surfaces of the electrodes 251 and 252 may be covered with the covering member 40, but the thickness of the covering member 40 is adjusted so that the surfaces 251 s and 252 s of the electrodes 251 and 252 are not covered with the covering member 40. In addition, the surfaces 251 s and 252 s of the electrodes may project from the covering member 40 or may be substantially flush (see FIG. 1B).

  As described above, the light emitting device 10 can include the diffusion member 50 on the first surface 21 side of the light emitting element 20. Diffusion member By providing the diffusion member 50, it is possible to suppress emission color unevenness emitted from the wavelength conversion member 60.

  Referring to FIG. 1B again, as described above, the light emitting device 10 can include the wavelength conversion member 60 on the first surface 11 side. The wavelength conversion member 60 is a member for converting a part of light transmitted through the inside into another wavelength. The wavelength conversion member 60 contains a phosphor that is excited by light passing through the inside thereof. Since the light emitting device 10 includes the wavelength conversion member 60, the light emitting device 10 having a light emission color different from the light emission color of the light emitting element 20 can be obtained. For example, by combining the light emitting element 20 that emits blue light and the wavelength conversion member 60 that absorbs blue light and emits yellow fluorescence, the light emitting device 10 that emits white light can be obtained.

  The diffusion member 50 is desirably provided so as to cover the first surface 21 of the light emitting element 20 and the first surface 31 of the translucent member 30. Light generated by the light emitting element 20 is directly extracted from the first surface 21 of the light emitting element 20 or emitted from the side surface 23 of the light emitting element 20, passes through the light transmitting member 30, and passes through the light transmitting member 30. 1 is indirectly taken out of the surface 31. Therefore, by disposing the diffusion member 50 so as to cover the first surface 21 of the light emitting element 20 and the first surface 31 of the translucent member 30, substantially all of the light generated by the light emitting element 20 can be removed. , Through the diffusion member 50. By passing through the diffusion member 50, it is possible to suppress color unevenness of light emission of the light emitting device 10.

  Generally, light emitted from the first surface 21 when the light emitting element 20 is turned on passes through the wavelength conversion member 60 and is extracted to the outside. However, since the blue wavelength from the first surface 21 of the light emitting element 20 is strong, It is considered that the light emitted from the wavelength conversion member contains a large amount of blue light, which is a cause of uneven emission color. By providing the diffusing member 50 between the first surface of the light emitting element and the wavelength conversion member, the blue wavelength emitted from the first surface 21 of the light emitting element 20 is reduced and is suppressed by passing through the wavelength conversion member 60. Light will be extracted.

  The wavelength conversion member 60 is desirably provided so as to cover the first surface 51 of the diffusion member 50 and the first surface 31 of the translucent member 30. Further, the diffusion member 50 and the wavelength conversion member 60 can cover the entire upper surface of the covering member. In other words, the side surface of the diffusion member 50 and the side surface of the wavelength conversion member 60 are flush with the side surface of the covering member 40.

<Production method>
A method for manufacturing the light emitting device 10 according to the present embodiment will be described with reference to FIG. In the method for manufacturing a light emitting device according to the present embodiment, a plurality of light emitting devices 10 can be manufactured at the same time.

  The sheet-shaped wavelength conversion member 600 (second surface 62) is bonded to the sheet-shaped diffusion member 500 by hot melt or an adhesive. The thickness of the wavelength conversion member can be, for example, 40 to 80 μm, and preferably 80 μm. In addition, since the thickness of the wavelength conversion member varies depending on the type of the phosphor used, it is most preferable that the thickness be about twice the thickness of the diffusion member.

  The laminated body in which the diffusion member 500 and the wavelength conversion member 600 are bonded to each other is placed on the first surface 52 of the light emitting element 20 via the adhesive 35 on the first surface 52 of the diffusion member 500 with the diffusion member 500 side facing up. (FIG. 2A). The thickness of the diffusion member can be set to, for example, 10 to 50 μm, and preferably 30 to 40 μm so that blue light emitted from the light emitting element 20 can be suppressed. However, since the thickness of the wavelength conversion member varies depending on the particle size of the phosphor used for the wavelength conversion member, it is preferable that the thickness of the diffusion member is half that of the wavelength conversion member 600.

  When the light emitting element 20 is arranged on the diffusion member 500 using the adhesive 35 (FIG. 2A), the first surface 21 of the light emitting element 20 is arranged to face the adhesive 35. The light emitting element 20 can be fixed to the diffusion member 500 with the adhesive 35. Instead of using an adhesive, it may be fixed to the diffusion member 500 by a translucent member 30 to be formed later.

  The translucent member 30 is formed so as to cover the side surface 23 of the light emitting element 20 and the region near the light emitting element 20 on the first surface 52 of the diffusion member 500 (FIG. 2B). When the translucent member 30 is formed of a translucent resin material, a liquid resin material 30L, which is a raw material of the translucent member 30, is supplied to the first side of the light emitting element 20 using a dispenser or the like. 2 (b) is applied along the boundary between the reference numerals 212 and 214 and the diffusion member 50. The liquid resin material 30L spreads on the diffusion member 50 and crawls on the side surface 23 of the light emitting element 20 due to surface tension. Thereafter, the liquid resin material 30L is cured by heating or the like to obtain the translucent member 30. The translucent member 30 formed around a certain light emitting element 20 and the light transmissive member 30 are arranged adjacent to the light emitting element 20. The translucent member 30 is formed so that the translucent member 30 formed around the light emitting element 20 does not contact.

  When the translucent member 30 is formed from the liquid resin material 30L, the outer surface 33 of the translucent member 30 is directed outward in the Z direction (that is, in a direction away from the side surface 23 of the light emitting element 20) due to surface tension. It can be inclined (FIG. 2 (b)).

  The outer surface 33 of the translucent member 30 and a portion of the first surface 52 of the diffusion member 500 that is not covered by the translucent member 30 (that is, a portion where the first surface 52 is exposed) It is covered with a covering member 400 (FIG. 2C). Furthermore, a portion of the second surface 22 of the light emitting element 20 that is not covered with the electrodes 251 and 252 (that is, a portion where the second surface 22 is exposed) may be covered with the covering member 40. At this time, the thickness (dimension in the −Z direction) of the covering member 400 is adjusted so that a part of the electrodes 251 and 252 (for example, the surfaces 251 s and 252 s of the electrodes 251 and 252) is exposed from the covering member 40. Is preferred. That is, the height of the second surface 42 of the covering member 40 may be equal to or less than the height of the surfaces 251 s and 252 s of the electrodes 251 and 252 with reference to the first surface 52 of the diffusion member 50.

  Along the broken line X1, which passes through the middle of the adjacent light emitting elements 20, (FIG. 2D), the covering member 400, the sheet-like diffusion member 500, and the sheet-like wavelength conversion member 600 are cut by a dicer or the like. As a result, the individual light emitting devices 10 are singulated (FIG. 2E). Thus, a plurality of light emitting devices 10 each including one light emitting element 20 can be manufactured at the same time.

<Embodiment 2>
3A and 3B show a light emitting device 15 according to the second embodiment. 4 (a) to 4 (f) show the manufacturing method. In the second embodiment, the light-emitting element 20 includes the light-emitting element 20, the light-transmitting member 30 provided on the side surface 23 of the light-emitting element 20, and the covering member 40 that covers the outer surface 33 of the light-transmitting member 30. The light emitting device 15 can include a diffusion member 50 on the first surface (upper surface) side functioning as a light emitting surface, and a wavelength conversion member 60 on the first surface (upper surface) side of the diffusion member. The third embodiment is different from the first embodiment in that the diffusion member 50 that covers the light emitting element 20 and the upper surface of the translucent member 30 is not provided on the entire upper surface of the covering member 40. The end 34 of the diffusion member 50 and the end of the wavelength conversion member 60 are separated from the side surface of the covering member 40. In other words, the side surface of the diffusion member 50 and the side surface of the wavelength conversion member 60 are located inside the side surface of the covering member 40. Thereby, the peeling of the diffusion member 50 and the wavelength conversion member 60 from the coating member 40 due to external contact can be reduced.

<Production method>
A method for manufacturing the light emitting device 15 according to the second embodiment will be described with reference to FIG. In the manufacturing method according to the second embodiment, manufacturing is performed using a sheet (for example, a heat-resistant sheet) that does not include a phosphor and a diffusing agent, instead of using a sheet that includes a phosphor and a diffusing agent. This sheet is a member that is finally removed and does not remain in the light emitting device. That is, in the first embodiment, the wavelength conversion member and the diffusion member constituting the light emitting device are each formed in a sheet shape and used as a part of a support member that supports a plurality of light emitting elements collectively in a process. On the other hand, the second embodiment is characterized in that each step is performed using a sheet that does not constitute a light emitting device as a supporting member. In the second embodiment, the wavelength conversion member including the phosphor and the diffusion member are formed in the latter half of the process. Here, the latter half of the process is, specifically, a process after the formation of the translucent member.

  The light emitting elements 20 are arranged on the upper surface 71 of the sheet 70 via the adhesive 35 (FIG. 4A). The sheet 70 is a member that is finally peeled and does not remain in the light emitting device. The translucent member 30 is formed so as to cover the side surface of the light emitting element 20 fixed to the upper surface 71 of the sheet 70 (FIG. 4B), and then the covering member 400 is formed (FIG. 4C). The details of each step are performed in the same procedure as in the manufacturing method of the first embodiment.

  After forming the covering member 400 as shown in FIG. 4C, the electrode surface of the light emitting element is attached to another heat-resistant sheet (reversed). Then, the heat-resistant sheet 70 is peeled off from the upper surface of the light emitting element. Thereby, as shown in FIG. 4D, the adhesive formed on the first surface 21 of the light emitting element 20 is exposed. At the same time, the upper surface of the translucent member and the upper surface 400a of the covering member 400 are also exposed. Next, as shown in FIG. 4E, a separately prepared diffusion member 50 and a wavelength conversion member 60 are formed on the light emitting element and the light transmitting member in this order.

  As a method of forming the diffusion member 50 and the wavelength conversion member 60, a method of bonding the individualized diffusion member 50 and the wavelength conversion member 60 with an adhesive can be used. The sheet of the diffusion member 50 and the sheet of the wavelength conversion member 60 may be separated and then bonded to each other in advance, or may be bonded to each of the sheets after separating the sheets. Further, a wavelength conversion member may be provided on the sheet of the diffusion member by a known technique such as a potting, spraying method, an electrostatic coating method, or a printing method, and may be singulated. Alternatively, a diffusion member may be provided on the sheet of the wavelength conversion member by potting, spraying, electrostatic coating, printing, or the like, and may be singulated.

  Further, as shown in FIG. 4D, the diffusion member 50 and the wavelength conversion member 60 are placed on the molded article embedded in the covering member 400 in a state where the upper surfaces of the light emitting element and the light transmitting member are exposed. , Potting, spraying, electrostatic coating, printing and the like. In this case, it is preferable to cover the upper surface of the covering member, which will be the cutting position later, with a mask or the like.

  In addition, when the wavelength conversion member and the diffusion member are formed in the latter half of the process, by using a sheet that continuously covers a plurality of light emitting elements instead of an individualized sheet, as illustrated in FIG. A light emitting device in which a wavelength conversion member is provided on the entire upper surface of the light emitting device can be provided. Similarly, the sheet of the wavelength conversion member and the sheet of the diffusion member are not separated into pieces in advance, but are attached in the latter half of the process in a state before being separated into pieces, so that light emission as shown in FIG. A light emitting device in which a wavelength conversion member is provided on the entire upper surface of the device can be provided.

  Finally, the covering member 400 is cut by a dicer or the like along the broken line X2 (FIG. 4E) passing through the middle of the adjacent light emitting elements 20. As a result, individual light emitting devices 15 are separated (FIG. 4E). Thus, a plurality of light emitting devices 15 each including one light emitting element 20 can be manufactured at the same time.

  Hereinafter, materials and the like suitable for each component of the light emitting devices of Embodiments 1 and 2 will be described.

(Light emitting element 20)
As the light emitting element 20, for example, a semiconductor light emitting element such as a light emitting diode can be used. The semiconductor light emitting device can include a light transmitting substrate 27 and a semiconductor laminate 28 formed thereon.

  As the light emitting element 20, a square shape in a top view can be used. Further, the light emitting device 17 using a polygonal shape other than a quadrangle, for example, a hexagonal shape shown in FIG. By using a hexagonal light-emitting element, the width of the light-transmitting member 30 (the distance between the side surface of the light-emitting element and the end of the light-transmitting member when viewed from the top surface side) can be reduced. Accordingly, the area of the light emitting portion to be irradiated is reduced, and high luminance can be maintained, so that color unevenness can be reduced. Further, by using a hexagonal light emitting element, a uniform illuminance distribution can be easily obtained from the light emitting device, and a point light source light emitting device having a small light emitting portion can be obtained.

(Translucent substrate 27)
The light-transmitting substrate 27 of the light-emitting element 20 includes, for example, a light-transmitting insulating material such as sapphire (Al 2 O 3) and spinel (MgA 12 O 4), or a semiconductor material that transmits light emitted from the semiconductor laminate 28 (for example, Nitride-based semiconductor material).

  The semiconductor laminate 28 includes a plurality of semiconductor layers. An example of the semiconductor laminate 28 includes three semiconductor layers of a first conductivity type semiconductor layer (for example, an n-type semiconductor layer), a light emitting layer (active layer), and a second conductivity type semiconductor layer (for example, a p-type semiconductor layer). (See FIG. 3). The semiconductor layer can be formed from a semiconductor material such as a III-V compound semiconductor and a II-VI compound semiconductor, for example. Specifically, a nitride-based semiconductor material (for example, InN, AlN, GaN, InGaN, AlGaN, InGaAlN, or the like) such as InXAlYGa1-X-YN (0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is used. it can.

  As the electrodes 251 and 252 of the light emitting element 20, an electric conductor can be used, and for example, a metal such as Cu is preferable.

(Translucent member 30)
The translucent member 30 can be formed from a translucent material such as translucent resin and glass. The light-transmitting resin is preferably a thermosetting light-transmitting resin such as a silicone resin, a silicone-modified resin, an epoxy resin, and a phenol resin. Since the translucent member 30 is in contact with the side surface 23 of the light emitting element 20, it is easily affected by the heat generated in the light emitting element 20 during lighting. The thermosetting resin has excellent heat resistance and is therefore suitable for the light transmitting member 30. It is preferable that the translucent member 30 has a high light transmittance. Therefore, it is usually preferable that an additive that reflects, absorbs, or scatters light is not added to the translucent member 30. However, in some cases, it is preferable to add an additive to the translucent member 30 in order to impart desirable characteristics.
For example, various fillers may be added to adjust the refractive index of the light transmitting member 30 or to adjust the viscosity of the light transmitting member (liquid resin material 300) before curing.

(Coating members 40 and 403)
The covering members 40 and 403 are formed of a material such that the relationship of the coefficient of thermal expansion with respect to the translucent member 30 and the light emitting element 20 has a predetermined relationship. That is, the covering members 40 and 403 are configured such that the thermal expansion coefficient difference ΔT40 between the covering members 40 and 403 and the light emitting element 20 is smaller than the thermal expansion coefficient difference ΔT30 between the translucent member 30 and the light emitting element 20. Material is selected. For example, when the light emitting element 20 includes the translucent substrate 27 of sapphire and the semiconductor laminate 28 made of a GaN-based semiconductor, the coefficient of thermal expansion of the light emitting element 20 is about 5 to 7 × 10 −6 / K. . On the other hand, when the translucent member 30 is formed from a silicone resin, the coefficient of thermal expansion of the translucent member 30 is 2-3 × 10 −5 / K. Therefore, ΔT40 <ΔT30 can be satisfied by forming the covering members 40 and 403 from a material having a smaller coefficient of thermal expansion than the silicone resin.

  When a resin material is used for the covering member 40, the coefficient of thermal expansion is generally on the order of 10 −5 / K, which is one order of magnitude larger than the coefficient of thermal expansion of the general light emitting element 20. However, by adding a filler or the like to the resin material, the coefficient of thermal expansion of the resin material can be reduced. For example, by adding a filler such as silica to the silicone resin, the coefficient of thermal expansion can be lower than that of the silicone resin before the filler is added.

  The resin material that can be used for the covering member 40 is particularly preferably a thermosetting translucent resin such as a silicone resin, a silicone-modified resin, an epoxy resin, and a phenol resin.

  The covering member 40 can be formed from a light reflective resin. The light reflective resin refers to a resin material having a reflectance of 70% or more with respect to light from the light emitting element 20. The light that reaches the covering member 40 is reflected and travels toward the first surface 11 (light-emitting surface) of the light-emitting device 10, so that the light extraction efficiency of the light-emitting device 10 can be increased.

  As the light-reflective resin, for example, a resin in which a light-reflective substance is dispersed in a translucent resin can be used. As the light reflective substance, for example, titanium oxide, silicon oxide, zirconium dioxide, potassium titanate, alumina, aluminum nitride, boron nitride, mullite, and the like are preferable. The light-reflective substance may be in the form of granules, fibers, thin plates, or the like. In particular, fibrous materials are preferable because the effect of lowering the coefficient of thermal expansion of the covering members 40 and 403 can be expected.

(Diffusion member 50)
The diffusion member 50 can be formed from a light-transmitting material such as a light-transmitting resin or glass. The light-transmitting resin is preferably a thermosetting light-transmitting resin such as a silicone resin, a silicone-modified resin, an epoxy resin, and a phenol resin. Since the diffusion member 50 is in contact with the first surface 21 of the light emitting element 20, it is easily affected by the heat generated in the light emitting element 20 during lighting. The thermosetting resin is suitable for the diffusion member 50 because of its excellent heat resistance. The diffusion member 50 preferably has a high light transmittance. Therefore, usually, it is preferable that an additive that reflects, absorbs, or scatters light is not added to the diffusion member 50. However, it may be preferable to add an additive to the diffusion member 50 in order to impart desirable properties. For example, various fillers may be added to adjust the refractive index of the diffusion member 50.

(Wavelength conversion member 60)
The wavelength conversion member 60 includes a phosphor and a translucent material. As the light-transmitting material, a light-transmitting resin, glass, or the like can be used. In particular, a translucent resin is preferable, and a thermosetting resin such as a silicone resin, a silicone-modified resin, an epoxy resin, and a phenol resin, and a thermoplastic resin such as a polycarbonate resin, an acrylic resin, a methylpentene resin, and a polynorbornene resin can be used. it can. Particularly, a silicone resin having excellent light resistance and heat resistance is preferable.

A phosphor that can be excited by light emission from the light emitting element 20 is used. For example, as a phosphor that can be excited by a blue light emitting element or an ultraviolet light emitting element, cerium-activated yttrium-aluminum-garnet-based phosphor (Ce: YAG); cerium-activated lutetium-aluminum-garnet-based phosphor (Ce: LAG); nitrogen-containing calcium aluminosilicate phosphor activated by europium and / or chromium (CaO-Al2O3-SiO2); silicate phosphor activated by europium ((Sr, Ba) 2SiO4); β Nitride-based phosphors such as sialon phosphor, CASN-based phosphor, and SCASN-based phosphor; KSF-based phosphor (K2SiF6: Mn); sulfide-based phosphor, quantum dot phosphor, and the like. By combining these phosphors with a blue light emitting element or an ultraviolet light emitting element, light emitting devices of various colors (for example, white light emitting devices) can be manufactured.
The wavelength conversion member 60 may contain various fillers for the purpose of adjusting the viscosity and the like.

(Seat 70)
The sheet (heat-resistant sheet) 70 is preferably made of a material that can be used even in a high-temperature region and has excellent insulating properties. The material is preferably polyimide or the like.

  As mentioned above, although several embodiments according to the present invention have been illustrated, it is needless to say that the present invention is not limited to the above-described embodiments, and can be arbitrary without departing from the gist of the present invention. .

10, 15, 17 Light-emitting device 11 First surface (upper surface) of light-emitting device
12. Second surface (lower surface) of light emitting device
Reference Signs List 20 light emitting element 21 first surface (upper surface) of light emitting element
22 Second surface (lower surface) of light emitting element
Reference Signs List 23 side surface of light emitting element 251, 252 electrode 30 translucent member 33 outer surface of translucent member 34 end of diffusion member 35 adhesive 40, 400 covering member 50 diffusion member 500 sheet diffusion member 600 sheet wavelength conversion 70 sheets (heat-resistant sheet)

Claims (9)

A bonding step of bonding the first surface of the wavelength conversion member and the first surface of the diffusion member having a thickness that is about half the thickness of the wavelength conversion member,
A first light emitting element disposing step of disposing a light emitting element on a second surface of the diffusing member, which is a surface facing the first surface of the diffusing member;
A first light transmitting member forming step of covering a side surface of the light emitting element and a part of the second surface of the diffusion member with a light transmitting member;
A first covering member forming step of covering an outer surface of the translucent member and a part of the second surface of the diffusing member with a covering member;
A first cutting step of cutting the wavelength conversion member, the diffusion member, and the coating member,
A method for manufacturing a light emitting device comprising:   The method according to claim 1, wherein a thickness of the diffusion member used in the bonding step is 30 to 40 μm.   The method for manufacturing a light emitting device according to claim 1, wherein an adhesive is provided between the diffusion member and the light emitting element in the first light emitting element disposing step.   The method for manufacturing a light emitting device according to claim 1, wherein the diffusion member and the wavelength conversion member used in the bonding step are sheet-shaped. A second light emitting element disposing step of disposing the light emitting elements on the first surface of the sheet;
A second translucent member forming step of covering a side surface of the light emitting element and a part of the first surface of the sheet with a translucent member;
A second covering member forming step of covering an outer surface of the translucent member and a part of the first surface of the sheet with a covering member;
Peeling the sheet from the light emitting element, a peeling step,
Forming a diffusion member and a wavelength conversion member in this order on the light emitting element and the translucent member, wherein the thickness of the diffusion member is about half the thickness of the wavelength conversion member. Process and
Cutting the coating member, a second cutting step,
A method for manufacturing a light emitting device comprising:   The method for manufacturing a light emitting device according to claim 5, wherein in the diffusion member forming step, the diffusion member covers at least a part of the covering member.   The method for manufacturing a light emitting device according to claim 5, wherein a thickness of the diffusion member used in the diffusion member forming step is 30 to 40 μm.   The method for manufacturing a light emitting device according to claim 5, further comprising an adhesive between the diffusion member and the light emitting element in the diffusion member forming step. A light-emitting element having a first surface serving as an upper surface, a second surface facing the first surface, and a plurality of side surfaces between the first surface and the second surface;
A translucent member that covers a part of the side surface of the light emitting element,
A covering member that covers an outer surface of the translucent member,
A diffusion member that covers the first surface of the light emitting element and the upper surface of the translucent member and has a thickness of 30 to 40 μm;
A wavelength conversion member that covers an upper surface of the diffusion member.

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