JP2015111626A - Light-emitting device and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and inexpensively provide a light-emitting device having a highly reliable configuration for enhancing light extraction efficiency, which is flexibly applicable to various light-emitting devices.SOLUTION: The light-emitting device includes: a package which has a recess provided on its upper surface and a first frame body surrounding the recess; a light-emitting element provided in the recess; a sealing body provided in the recess and covering the light-emitting element; and an uneven structure sheet having an uneven structure on its upper surface. The uneven structure sheet covers at least a part of a light extraction surface of the sealing body and at least a part of an upper surface of the first frame body.

Description

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

  2. Description of the Related Art Conventionally, a light emitting device including an LED (Light Emitting Diode) chip made of a semiconductor is known. In such a light emitting device, in order to protect the LED chip itself or a wire electrically connected to the LED chip, etc., in order to improve the extraction efficiency of the emitted light from the LED chip, further, as necessary In order to disperse the phosphor, the LED chip is covered with a sealing resin. Light emitted from the LED chip passes through the sealing resin and is emitted from the surface of the sealing resin (light extraction surface) toward the outside of the sealing resin.

  Here, part of the light transmitted through the sealing resin is totally reflected at the interface between the sealing resin and the air and is not emitted outside due to the difference in refractive index between the sealing resin and the air. As a method for solving such a problem, Patent Documents 1 to 3 propose providing unevenness on the light extraction surface of the sealing resin. Thereby, the reflection angle of light at the interface between the sealing resin and the air changes. Accordingly, light that has returned to the light emitting device side due to total reflection or the like can be re-incident on the interface at a different angle, so that the amount of light that does not finally pass through the sealing resin is reduced. Therefore, it is considered that the light extraction efficiency is increased because the effective light transmittance is increased.

JP 2003-234509 A JP 2007-227919 A JP 2008-227456 A

  However, in Patent Documents 1 and 2, the sealing resin is processed for each LED chip or the sealing resin is processed by the nanostamp method, and in Patent Document 3, the light-extracting surface of the sealing resin is formed for each LED chip. Affix to. Therefore, the manufacturing process of the light emitting device becomes complicated, and the manufacturing cost of the light emitting device increases. In addition, in the high-power LED package described in Patent Document 3, during use, the adhesion between the uneven film and the sealing resin due to heat generation may be reduced, so that the uneven film takes out the light from the sealing resin. It becomes easy to peel off from the surface.

  The present invention has been made in view of such a point, and an object thereof is a structure that can be flexibly applied to various light-emitting devices and has a highly reliable structure for increasing the light extraction efficiency. It is to provide a light emitting device that is simple and inexpensive.

  The light emitting device of the present invention includes a package having a recess provided on the upper surface and a first frame body portion surrounding the recess, a light emitting element provided in the recess, a light emitting element provided in the recess, and covering the light emitting element. A sealing body and an uneven structure sheet having an uneven structure on the upper surface are provided. The concavo-convex structure sheet covers at least a part of the light extraction surface of the sealing body and at least a part of the upper surface of the first frame body part. Preferably, the package has an external connection terminal on at least one of the side surface and the lower surface.

  Such a method for manufacturing a light emitting device includes a step of preparing a package base material having a plurality of packages and a connecting portion for connecting the packages, a light emitting element is provided in a recess of the package, and the light emitting element is sealed with a sealing body. A step of covering, a step of providing a concavo-convex structure sheet so as to cover at least a part of the light extraction surface of the sealing body and at least a part of the upper surface of the first frame body part surrounding the recess, and cutting the connection part To obtain a plurality of light emitting devices.

  The light emitting device of the present invention may have the following configuration. The light emitting device includes a substrate, a light emitting element provided on the upper surface of the substrate, a sealing body provided on the upper surface of the substrate and covering the light emitting element, and a second frame provided on the upper surface of the substrate and surrounding the sealing body. And an uneven structure sheet having an uneven structure on the upper surface. The concavo-convex structure sheet covers at least a part of the light extraction surface of the sealing body and at least a part of the upper surface of the second frame body part. Preferably, external connection terminals are provided on the upper surface of the substrate, and the concavo-convex structure sheet covers at least a part of the upper surface of the substrate and exposes the external connection terminals.

  A manufacturing method of such a light emitting device includes a step of arranging a plurality of light emitting elements on an upper surface of a substrate base material at intervals, covering each of the light emitting elements with a sealing body, and at least a light extraction surface of the sealing body Providing a concavo-convex structure sheet so as to cover a part and at least a part of the upper surface of the second frame part surrounding the sealing body, and obtaining a plurality of light emitting devices by cutting the substrate base material. . Preferably, external connection terminals are provided on the upper surface of the substrate base material, and holes for exposing the external connection terminals are formed in the concavo-convex structure sheet.

  In the present invention, the configuration for increasing the light extraction efficiency can be flexibly applied to various light emitting devices, and the light emitting device having a highly reliable configuration for increasing the light extraction efficiency can be simply used. And can be provided at low cost.

(A) is a top view of the light-emitting device of one Embodiment of this invention, FIG.1 (b) is the sectional drawing. (A), (b) is principal part sectional drawing of the light-emitting device which shows an example of a structure of an uneven structure sheet. (A)-(c) is sectional drawing which shows an example of an uneven structure. (A)-(d) is a top view which shows an example of an uneven structure. (A), (b) is sectional drawing which shows the manufacturing method of the light-emitting device of one Embodiment of this invention in order of a process. (A) is a top view of the light-emitting device of one Embodiment of this invention, (b) is the sectional drawing. (A) is a top view of the light-emitting device of one Embodiment of this invention, (b) is sectional drawing of the uneven structure sheet | seat of one Embodiment of this invention.

  Hereinafter, a light-emitting device and a manufacturing method thereof according to the present invention will be described with reference to the drawings. In the drawings of the present invention, the same reference numerals represent the same or corresponding parts. In addition, dimensional relationships such as length, width, thickness, and depth are changed as appropriate for clarity and simplification of the drawings, and do not represent actual dimensional relationships.

  In the following, in order to express the positional relationship, the part described on the lower side of the drawing may be expressed as “lower” and the part described on the upper side of the drawing may be expressed as “upper”. This is an expression for convenience and is different from “upper” and “lower” defined for the direction of gravity.

<First Embodiment>
<Configuration of light emitting device>
FIG. 1A is a plan view of the light emitting device 10 according to the first embodiment of the present invention, and FIG. 1B is a cross-sectional view thereof. The light emitting device 10 includes a package 11, a light emitting element 12, a sealing body 15, and an uneven structure sheet 20. Note that the concavo-convex structure sheet 20 and the sealing body 15 are not shown in FIG.

The package 11 has a substantially rectangular parallelepiped shape whose outer shape in plan view is a rectangle of 5.0 × 3.0 mm, for example, and has a recess 16 and a first frame body 17. The hollow portion 16 includes a side surface that is inclined so as to have a wide opening from the bottom surface of the hollow portion 16 toward the upper surface of the package 11, and is open on the upper surface of the package 11. The first frame body portion 17 surrounds the hollow portion 16 and has, for example, an inverted square frustum shape. The material of the package 11 is preferably a material excellent in reflectivity, and may be, for example, a white resin to which titanium oxide or the like is added, or a sintered body such as aluminum oxide (Al ₂ O ₃ ). The ceramic which consists of may be sufficient.

  The package 11 is provided with a first electrode 13a and a second electrode 13b. The first electrode 13 a and the second electrode 13 b are configured as a pair so as to function as positive and negative electrodes, and a part thereof is provided so as to be exposed on the side surface or the bottom surface of the package 11. Note that the first electrode 13 a and the second electrode 13 b may be formed as thin films on the upper surface of the package 11. A portion where the first electrode 13a is exposed on the side surface or bottom surface of the package 11 functions as the first external connection terminal 113a, and a portion where the second electrode 13b is exposed on the side surface or bottom surface of the package 11 functions as the second external connection terminal 113b. To do. In the light emitting device 10, the first external connection terminal 113a is a portion protruding from the side surface of the package 11 in the first electrode 13a, and the second external connection terminal 113b is a portion protruding from the side surface of the package 11 in the second electrode 13b. It is.

  The light emitting element 12 is provided on the bottom surface of the recess 16. For example, the light emitting element 12 may be provided on the upper surface of one of the first electrode 13a and the second electrode 13b (the second electrode 13b in the present embodiment) of the bottom surface of the recess portion 16, or the recess portion. The bottom surface of 16 may be provided between the first electrode 13a and the second electrode 13b.

  The light emitting element 12 may be an LED chip made of a compound semiconductor such as AlGaInN, AlGaAs, InGaAs, or AlGaInP, or an LED chip made of an organic material. The type of the compound semiconductor or organic material is preferably determined as appropriate based on the wavelength of light emitted from the light emitting element 12, and a compound semiconductor material capable of emitting ultraviolet light, blue light, green light, red light, infrared light, or the like. It is preferable to use it. As an example of the light emitting element 12, a blue LED chip using a gallium nitride based semiconductor can be cited.

  A part of the emitted light from the light emitting element 12 is reflected by the inclined side surface of the recess 16. Therefore, the package 11 is preferably made of a material having excellent reflectance (described above).

  Such a light emitting element 12 is provided with a first terminal 12a and a second terminal 12b. The first terminal 12a is connected to the first electrode 13a via the first bonding wire 14a, and the second terminal 12b is connected to the second electrode 13b via the second bonding wire 14b. As described above, a part of the first electrode 13a functions as the first external connection terminal 113a, and a part of the second electrode 13b functions as the second external connection terminal 113b. Therefore, external power is supplied to the light emitting element 12 by connecting the first external connection terminal 113a and the second external connection terminal 113b to a wiring board or the like.

  The sealing body 15 is provided in the recess portion 16 so as to cover the light emitting element 12, the first bonding wire 14 a and the second bonding wire 14 b, and the recess portion 16 so that the sealing resin fills the recess portion 16. It is infused inside. The sealing resin is preferably, for example, a thermosetting epoxy resin or a silicone resin. Thereby, since the reliability of the sealing body 15 and its transparency increase, the light extraction efficiency of the light emitting device 10 is increased. The sealing resin may be a material other than resin, for example, low melting point glass.

When the light-emitting device 10 is a light-emitting device that combines a light-emitting element 12 and a phosphor that converts emitted light from the light-emitting element 12 into light having a longer wavelength than the emitted light, the sealing body 15 includes a phosphor (preferably Are dispersed in the form of particulate phosphors. As a material of the phosphor, for _{example, YAG ((Y 1-x} Gd x) 3 Al 5 O 12: Eu 2+, yttrium aluminum garnet), TAG (terbium-aluminum-garnet), LAG (lutetium aluminum Garnet), β sialon (Si—Al—O—N—Eu), α sialon (Si—Al—O—N—Eu), Ba— (Sr) —Si—O—Eu, CASN (CaAlSiN ₃ : Eu) ²⁺ ), SCASN (Sr _x Ca _1-x AlSiN ₃ : Eu ²⁺ ) or K ₂ SiF ₆ : Mn ⁴⁺ . In addition, the said composition ratio of the fluorescent substance with which the composition ratio is described among the said specific examples is a representative example, Comprising: It is not limited to the said composition ratio. The composition ratio x takes a value from 0 to 1. When the phosphor is in the form of particles, the particle size is preferably, for example, several μm to several tens of μm. The sealing body 15 may be mixed with particles (for example, silica particles) that act as a light scattering agent or a viscosity adjusting agent (decreasing the sedimentation rate of the phosphor).

  In the concavo-convex structure sheet 20, the concavo-convex structure 21 is located on the surface side of the light emitting device 10 (upper surface of the concavo-convex structure sheet 20) in a state where the concavo-convex structure sheet 20 covers the light extraction surface 15 </ b> A of the sealing body 15. .

  Such a concavo-convex structure sheet 20 covers at least a part of the first frame upper surface 17A, which covers the light extraction surface 15A of the sealing body 15 and is the upper surface of the first frame body portion 17 exposed from the sealing body 15. cover. Preferably, the concavo-convex structure sheet 20 covers the light extraction surface 15A of the sealing body 15 and the entire first frame upper surface 17A. Thus, since the uneven structure sheet 20 covers the light extraction surface 15A of the sealing body 15, total reflection of light at the interface between the uneven structure 21 and the sealing body 15 can be suppressed. Further, the reflection angle of light changes at the interface between the concavo-convex structure sheet 20 and air. Therefore, since the light that has returned to the light emitting device 10 side due to total reflection or the like can be re-incident on the interface at another angle, the amount of light that does not finally pass through the sealing body 15 is reduced. The light transmittance becomes higher. From the above, the light extraction efficiency is improved.

  The first frame upper surface 17A is wider than the light extraction surface 15A of the sealing body 15. Therefore, the contact area between the uneven structure sheet 20 and the first frame upper surface 17A is larger than the contact area between the uneven structure sheet 20 and the light extraction surface 15A of the sealing body 15. Generally, when a silicone resin is used as the sealing resin, it is said that the adhesion between the uneven structure sheet and the light extraction surface of the sealing body is lowered. However, since the concavo-convex structure sheet 20 also covers at least a part of the first frame upper surface 17A, the adhesion between the concavo-convex structure sheet 20 and the light extraction surface 15A of the sealing body 15 can be enhanced. Therefore, even when the light emitting device 10 is used for a long time, the adhesion state between the concavo-convex structure sheet 20 and the light extraction surface 15A of the sealing body 15 can be maintained, so that the reliability of the light emitting device 10 is increased. As described above, it is possible to provide the light-emitting device 10 that can be flexibly applied to various light-emitting devices and includes the configuration (uneven structure sheet 20) for increasing the light extraction efficiency, easily and inexpensively. “The light extraction surface 15 </ b> A of the sealing body 15” means the surface of the sealing body 15 exposed from the package 11.

  As described above, the first external connection terminal 113 a and the second external connection terminal 113 b are exposed on the side surface or the bottom surface of the package 11. This eliminates the need to form holes in the concavo-convex structure sheet 20 for exposing the first external connection terminals 113a and the second external connection terminals 113b. Therefore, since the adhesiveness between the uneven structure sheet 20 and the light extraction surface 15A of the sealing body 15 is further increased, even when the light emitting device 10 is used for a long time, the uneven structure sheet 20 and the sealing body 15 The adhesion state with the light extraction surface 15A is further maintained. Therefore, the reliability of the light emitting device 10 is further increased. As a result, it is possible to provide the light-emitting device 10 having a configuration that can be flexibly applied to various light-emitting devices and having a configuration (uneven structure sheet 20) for increasing the light extraction efficiency more easily and at a lower cost. .

  The configuration of the concavo-convex structure sheet 20 is not particularly limited as long as it has the concavo-convex structure 21 on the upper surface thereof. The concavo-convex structure sheet 20 may be composed only of the concavo-convex structure 21 as shown in FIG. 1B, for example, or may have the configuration shown in FIG. 2A or 2B. If the uneven structure sheet 20 has a laminated structure as shown in FIG. 2A or 2B, the strength of the uneven structure sheet 20 is increased. 2A and 2B are main part cross-sectional views of the light-emitting device showing an example of the configuration of the concavo-convex structure sheet 20.

  The uneven structure sheet 20 shown in FIG. 2A has a first sheet member 23 and a second sheet member 27. The first sheet member 23 covers the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A. The second sheet member 27 includes only the concavo-convex structure 21.

  The concavo-convex structure sheet 20 shown in FIG. 2B is bonded to the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A via the adhesive layer 31, and FIG. The first sheet member 23 and the second sheet member 27 shown in FIG. The second sheet member 27 shown in FIG. 2B has a sheet base material 25 and a concavo-convex structure 21 provided on the upper surface of the sheet base material 25.

  Although the material of the concavo-convex structure sheet 20 is not particularly limited, for example, a material having a refractive index close to the refractive index of the sealing resin is preferable. Since the refractive index of the epoxy resin or silicone resin constituting the sealing resin is about 1.4 to 1.55, the refractive index of the concavo-convex structure sheet 20 is preferably about 1.4 to 1.55. Thus, if the refractive index of the uneven structure 21 is close to the refractive index of the sealing resin, it is possible to further prevent total reflection of light at the interface between the uneven structure 21 and the sealing body 15. As a result, the light extraction efficiency is further improved.

  In addition, the material of the concavo-convex structure sheet 20 is preferably a material having excellent strength and transparency in a necessary wavelength region, and is preferably selected from the viewpoint of processability of the concavo-convex shape. When the concavo-convex structure sheet 20 includes the first sheet member 23 and the second sheet member 27, the first sheet member 23 is preferably made of a polyester resin, and the second sheet member 27 is preferably made of an acrylic resin.

  The “concavo-convex structure 21” is configured by alternately arranging convex portions 21A and concave portions 21B. The configuration of the uneven structure 21 is not particularly limited. 3A to 3C are cross-sectional views illustrating an example of the uneven structure 21. FIG. 4A to 4D are plan views showing an example of the uneven structure 21. FIG. Hereinafter, the concavo-convex structure 21 will be described by taking the concavo-convex structure sheet 20 shown in FIG. 2A as an example.

  The concavo-convex structure 21 may be configured by providing a plurality of convex portions 21A at intervals on the upper surface of the first sheet member 23 (FIG. 1B, FIG. 3A, FIG. 3B). )), A plurality of recesses 21B may be provided on the upper surface of the first sheet member 23 at intervals (FIG. 3C).

  The convex portion 21A or the concave portion 21B provided on the upper surface of the first sheet member 23 with a space is rectangular (FIG. 3 (a)), a square, or a polygon other than a square (for example, FIG. 1 (b)). 3) or a semicircular shape (FIGS. 3B and 3C).

  The convex portions 21A or the concave portions 21B provided at intervals on the upper surface of the first sheet member 23 may be arranged at intervals in two different directions in plan view (FIG. 4A). 4 (b) and 4 (d)) may be formed in a stripe shape extending in one direction (FIG. 4 (c)). In the case shown in FIG. 4 (a), FIG. 4 (b), or FIG. 4 (d), it is preferable that the convex portion 21A or the concave portion 21B is a polygon or a circle other than a rectangle, a square, and a rectangle in plan view. In addition, with respect to the “different two directions”, the angle at which the two directions intersect may be 90 degrees, or may be an angle different from 90 degrees (for example, 60 degrees).

  When the concavo-convex structure 21 is configured by providing a plurality of convex portions 21A at intervals on the upper surface of the first sheet member 23 (FIG. 1B, FIG. 3A, FIG. 3B). The concave portion 21 </ b> B has a bottom surface in which the convex portion 21 </ b> A is not formed in the upper surface of the first sheet member 23. On the other hand, when the concavo-convex structure 21 is configured by providing a plurality of concave portions 21B with an interval on the upper surface of the first sheet member 23 (FIG. 3C), the convex portion 21A has the concave portion 21B as the first concave portion 21B. When formed on the upper surface of the sheet member 23, it is a portion remaining without forming the recess 21B.

  The interval between adjacent convex portions 21A or concave portions 21B is particularly preferably 50 nm or more and 5 μm or less. Thereby, since the space | interval of the adjacent convex part 21A or the recessed part 21B becomes close to the wavelength (450-650 nm) of the emitted light from the light emitting element 12, the light scattering effect and the light diffraction effect by the uneven structure sheet | seat 20 are obtained. . More preferably, the interval between adjacent convex portions 21A or concave portions 21B is not less than 300 nm and not more than 1 μm. Thereby, since the space | interval of adjacent convex part 21A or the recessed part 21B becomes still closer to the wavelength of the emitted light from the light emitting element 12, the light scattering effect and the light diffraction effect by the uneven structure sheet | seat 20 are obtained effectively. Moreover, even if the space | interval of the adjacent convex part 21A or the recessed part 21B is 5 micrometers or more, since the light-scattering effect is acquired, it is preferable. The convex portions 21 </ b> A or the concave portions 21 </ b> B may not be arranged at equal intervals on the upper surface of the first sheet member 23.

  The height of the convex portion 21A is preferably 50 nm or more and 5 μm or less. In this case, if the convex portion 21A has a shape other than a spherical shape and the height of the convex portion 21A is larger than the interval between the adjacent convex portions 21A, the concave-convex structure increases toward the outside of the light emitting device 10. Since the refractive index of the sheet 20 changes, the light scattering effect and the light diffraction effect by the uneven structure sheet 20 can be obtained more effectively. Therefore, when the height of the convex portion 21A is 50 nm or more and 5 μm or less, the outer shape of the convex portion 21A is a shape other than a spherical shape, and the height of the convex portion 21A with respect to the interval between the adjacent convex portions 21A. Is preferably 0.5 times or more and 2 times or less.

  Similarly, the depth of the recess 21B is preferably 50 nm or more and 5 μm or less. In this case, if the outer shape of the concave portion 21B is a shape other than a spherical shape and the depth of the concave portion 21B is larger than the interval between the adjacent concave portions 21B, the concave-convex structure sheet 20 moves toward the outside of the light emitting device 10. Since the refractive index changes, the light scattering effect and the light diffraction effect by the uneven structure sheet 20 can be obtained more effectively. Therefore, when the depth of the recess 21B is 50 nm or more and 5 μm or less, the outer shape of the recess 21B is a shape other than a spherical shape, and the depth of the recess 21B is 0.5 with respect to the interval between the adjacent recesses 21B. It is preferable that they are 2 times or more and 2 times or less.

<Manufacture of light emitting device>
5A and 5B are cross-sectional views showing the method for manufacturing the light emitting device of this embodiment in the order of steps. First, the structure shown in FIG. 5A is formed. Specifically, for example, a package base material 111 in which the first electrode 13a and the second electrode 13b are integrally formed via the connection portion 13c by insert molding is prepared. The package base material 111 includes two or more packages 11 and a connection portion 13c that connects the packages 11 to each other. The connection portion 13c is exposed from the package 11, and becomes the first external connection terminal 113a or the second external connection terminal 113b after a dicing process described later.

  After the die bond material is applied to the bottom surface of the recess portion 16 of the package 11, the light emitting element 12 is fixed to the bottom surface of the recess portion 16 through the die bond material. The first terminal 12a of the light emitting element 12 and the first electrode 13a are connected via the first bonding wire 14a, and the second terminal 12b and the second electrode 13b of the light emitting element 12 are connected via the second bonding wire 14b. To do.

  After preparing the sealing agent in which the phosphor is dispersed in the sealing resin, a predetermined amount of the sealing agent is supplied to the upper surface of the light emitting element 12 using, for example, a dispenser. Thereby, the light emitting element 12, the 1st bonding wire 14a, and the 2nd bonding wire 14b are covered with a sealing agent. The sealing body 15 is formed by curing the sealing resin in the sealing agent.

  Next, as shown in FIG. 5B, the concavo-convex structure sheet 20 is adhered. Specifically, the adhesive layer 31 is provided so as to cover the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A. The uneven structure sheet 20 is adhered to the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A through the adhesive layer 31. Preferably, an adhesive layer 31 is provided so as to cover the entire top surface of the structure shown in FIG. 5A, and the concavo-convex structure sheet 20 is provided on the entire top surface of the structure shown in FIG. Adhere.

  Thus, by providing the uneven structure sheet 20 also on the first frame upper surface 17 </ b> A, the uneven structure sheet 20 can be provided simultaneously on the light extraction surfaces 15 </ b> A of the plurality of sealing bodies 15. Moreover, when cutting the connection part 13c, the uneven structure sheet | seat 20 can also be cut | disconnected. From these things, the formation process of the concavo-convex structure sheet 20 can be simplified. Therefore, the light-emitting device 10 having a configuration that can be flexibly applied to various light-emitting devices and a configuration for increasing light extraction efficiency can be provided simply and inexpensively.

  The concavo-convex structure 21 of the concavo-convex structure sheet 20 is preferably formed in advance by, for example, a nanoimprinting method. From the viewpoint of easy handling of the uneven structure sheet 20, the thickness of the uneven structure sheet 20 is preferably about 20 to 200 μm. However, even if the thickness of the uneven structure sheet 20 is about 1 μm, the uneven structure sheet 20 can be held by applying tension to the uneven structure sheet 20. The uneven structure sheet 20 used in this step is not limited to the uneven structure sheet 20 shown in FIG. 2B, and may be the uneven structure sheet 20 shown in FIG. 1B or 2A. .

  Then, the connection part 13c and the uneven structure sheet | seat 20 are cut | disconnected by the dicing method etc. (cutting process). Thereby, the several light-emitting device 10 is obtained simultaneously.

<Second Embodiment>
<Configuration of light emitting device>
FIG. 6A is a plan view of a light emitting device 40 according to the second embodiment of the present invention, and FIG. 6B is a sectional view thereof. The light emitting device 40 is a COB (Chip On Board) type light emitting device in which two or more light emitting elements 42 are provided on the upper surface 41 </ b> A of the substrate 41, and includes the substrate 41, two or more light emitting elements 42, and a sealing body 45. And a dam ring (second frame part) 47 and the concavo-convex structure sheet 20. In the light emitting device 40, the first external connection terminal and the second external connection terminal are provided on the upper surface 41A of the substrate 41, and the dam ring 47 is not the first frame body portion 17 but the upper surface 41A of the substrate 41. Is different from the light emitting device 10 of the first embodiment in that it encloses the sealing body 45. In the following, points different from the first embodiment will be mainly described.

The substrate 41 has a flat plate shape whose outer shape in plan view is a rectangle of 20 × 24 mm, for example. The material of the substrate 41 is not particularly limited, is preferably a ceramic, for example made of a sintered body such as Al ₂ O _3. As the substrate 41, for example, a substrate in which at least a part of the surface of a substrate body made of a metal such as aluminum is coated with an insulating material may be used.

  On the upper surface 41A of the substrate 41, a first electrode 43a and a second electrode 43b are provided. The first electrode 43a and the second electrode 43b are configured in pairs so as to function as positive and negative electrodes. The upper surface of the first electrode 43a is exposed from the uneven structure sheet 20 and functions as a first external connection terminal, and the upper surface of the second electrode 43b is exposed from the uneven structure sheet 20 and functions as a second external connection terminal.

  The two or more light emitting elements 42 are provided on the upper surface 41 </ b> A of the substrate 41 at an interval. Each light emitting element 42 is preferably configured in the same manner as the light emitting element 12 of the first embodiment, and is preferably a blue LED chip having a peak wavelength of emitted light of 450 nm, for example. The first terminal of each light emitting element 42 is connected to the first electrode 43a via the first bonding wire 44a, and the second terminal of each light emitting element 42 is connected to the second electrode 43b via the second bonding wire 44b. .

  The sealing body 45 is provided on the upper surface 41A of the substrate 41 so as to cover the two or more light emitting elements 42, a part of the first bonding wire 44a, and a part of the second bonding wire 44b. A dam ring 47 is in contact with the outer periphery. The dam ring 47 has a ring shape on the upper surface 41A of the substrate 41, and is provided between the light emitting element 42 located on the outermost surface 41A of the substrate 41 and the first electrode 43a and the second electrode 43b. . Such a dam ring 47 prevents the flow of the sealing resin or the phosphor (the material constituting the sealing body 45) toward the first electrode 43a side or the second electrode 43b side.

  The concavo-convex structure sheet 20 covers the light extraction surface 45A, which is the upper surface of the sealing body 45, and covers at least a part of the dam ring upper surface 47A, which is the upper surface of the dam ring 47 exposed from the sealing body 45. Thereby, the effect described in the first embodiment can be obtained.

  It is preferable that the concavo-convex structure sheet 20 is not provided on the upper surface of the first electrode 43a, the upper surface of the second electrode 43b, and their peripheral regions. Therefore, it is preferable that the concavo-convex structure sheet 20 be formed with holes for exposing the upper surface of the first electrode 43a, the upper surface of the second electrode 43b, and their peripheral regions. Thereby, external power can be supplied to the light emitting element 42.

<Manufacture of light emitting device>
The light emitting device 40 can be manufactured according to the following method. First, a substrate base material is prepared. The substrate base material is a single sheet in which the substrates 41 are arranged vertically and horizontally. Preferably, the thickness of a portion of the substrate base material that is cut in a cutting step by a dicing method, which will be described later, is thin. For example, a split groove is formed in a portion of the substrate base material that is cut in the cutting step. Has been. A dam ring 47 is provided in each of the upper surface of the substrate base material and divided into the division grooves, and the first electrode 43 a and the second electrode 43 b are provided outside each dam ring 47. .

  A die bond material is applied to a region surrounded by the dam ring 47 on the upper surface of the substrate base material at intervals. The light emitting element 42 is fixed to the upper surface of the substrate base material through each of the die bond materials. The first terminal of the light emitting element 42 and the first electrode 43a are connected via the first bonding wire 44a, and the second terminal of the light emitting element 42 and the second electrode 43b are connected via the second bonding wire 44b.

  After preparing the sealing agent in which the phosphor is dispersed in the sealing resin, a predetermined amount of the sealing agent is supplied to the inside of the dam ring 47 using, for example, a dispenser. Thereby, the light emitting element 42, a part of the first bonding wire 44a, and a part of the second bonding wire 44b are covered with the sealant. The sealing body 45 is formed by curing the sealing resin in the sealing agent.

  Next, the uneven structure sheet 20 is adhered. Specifically, an adhesive layer is provided so as to cover the light extraction surface 45A of the sealing body 45 and at least a part of the dam ring upper surface 47A. The uneven structure sheet 20 is bonded to the light extraction surface 45A of the sealing body 45 and a part of the dam ring upper surface 47A through the adhesive layer. Thus, also in this embodiment, since the uneven structure sheet | seat 20 is provided also in the dam ring upper surface 47A, the effect as described in the said 1st Embodiment is acquired. In addition, it is preferable that the concavo-convex structure sheet 20 to be used is previously formed with holes for exposing the upper surface of the first electrode 43a, the upper surface of the second electrode 43b, and their peripheral regions. Thereby, external power can be supplied to the light emitting element 42.

  Subsequently, the substrate base material and the concavo-convex structure sheet 20 are cut by a dicing method or the like (cutting step). Thereby, the several light-emitting device 40 is obtained simultaneously. Examples of the method for cutting the substrate base material include applying an external force to the dividing grooves.

<Third Embodiment>
FIG. 7A is a plan view of a light emitting device 60 according to the third embodiment of the present invention, and FIG. 7B is a cross-sectional view of the concavo-convex structure sheet 20 of the present embodiment. Note that the sealing body 15 is not shown in FIG. The light emitting device 60 is different from the light emitting device 10 of the first embodiment in that the size of the package 11 is different and that the uneven structure sheet 20 shown in FIG. 7B is provided. In the following, points different from the first embodiment will be mainly described.

  The package 11 has a substantially rectangular parallelepiped shape whose planar view outer shape is, for example, a rectangle having a size of 7.0 × 3.0 mm, and includes a recessed portion 16 and a first frame body portion 17. The first frame body portion 17 has, for example, an inverted square frustum shape.

  The uneven structure sheet 20 covers a part of the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A. Thus, even when the concavo-convex structure sheet 20 only covers a part of the light extraction surface 15A, the effects described in the first embodiment can be obtained.

  Further, in the concavo-convex structure sheet 20, the interval between the adjacent convex portions 21 </ b> A is wide (for example, 30 to 300 μm) on the side close to the light emitting element (for example, 30 to 300 μm), but from the central side of the light emitting device 60 to its peripheral side. It becomes narrower (for example, about 5 μm). Thus, since the uneven structure sheet 20 of this embodiment has a “Fresnel lens” shape, the directivity of light such as converging or diffusing the light emitted from the light emitting element above the uneven structure sheet 20 is achieved. Control effect (lens effect) is obtained.

  As described above, the light emitting device 10 illustrated in FIGS. 1A and 1B includes the package 11 having the recess 16 provided on the upper surface and the first frame body 17 surrounding the recess 16, and the recess. The light emitting element 12 provided in the part 16, the sealing body 15 provided in the hollow part 16, and covering the light emitting element 12, and the uneven structure sheet 20 having the uneven structure 21 on the upper surface are provided. The uneven structure sheet 20 covers at least a part of the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A. The structure (uneven structure sheet 20) for increasing the light extraction efficiency of the light emitting device 10 can be flexibly applied to various light emitting devices. Further, the light emitting device 10 can be provided simply and inexpensively. This can be said also in the light emitting device 60 shown in FIG.

  In the light emitting devices 10 and 60, the package 11 preferably has external connection terminals 113a and 113b on at least one of a side surface and a lower surface. Thereby, the first external connection terminal 113a and the second external connection terminal 113b can be secured while the uneven structure sheet 20 is formed on the entire top surface of the package 11, for example. Therefore, it is possible to provide the light-emitting device 10 that can be flexibly applied to various light-emitting devices and includes the configuration (uneven structure sheet 20) for increasing the light extraction efficiency more easily and at a lower cost.

  A light emitting device 40 shown in FIGS. 6A and 6B includes a substrate 41, a light emitting element 42 provided on the upper surface 41 </ b> A of the substrate 41, and a sealing provided on the upper surface 41 </ b> A of the substrate 41 to cover the light emitting element 42. A body 45, a second frame body portion 47 provided on the upper surface 41A of the substrate 41 and surrounding the sealing body 45, and the concavo-convex structure sheet 20 having a concavo-convex structure on the upper surface. The uneven structure sheet 20 covers at least a part of the light extraction surface 45A of the sealing body 45 and at least a part of the second frame upper surface 47A. The structure (uneven structure sheet 20) for increasing the light extraction efficiency of the light emitting device 40 can be flexibly applied to various light emitting devices. Further, the light emitting device 40 can be provided simply and inexpensively.

  In the light emitting device 40, an external connection terminal is preferably provided on the upper surface 41 </ b> A of the substrate 41. The concavo-convex structure sheet 20 preferably covers at least a part of the upper surface 41A of the substrate 41, while exposing the external connection terminals. Thereby, external power can be supplied to the light emitting element 42.

  The manufacturing method of the light emitting devices 10 and 60 includes a step of preparing a package base material 111 having a plurality of packages 11 and a connection portion 13 c for connecting the packages 11, and a light emitting element 12 is provided in the recess 16 of the package 11. The step of covering the light emitting element 12 with the sealing body 15 and the step of providing the concavo-convex structure sheet 20 so as to cover at least a part of the light extraction surface 15A of the sealing body 15 and at least a part of the first frame upper surface 17A. And a step of obtaining a plurality of light emitting devices 10 and 60 by cutting the connecting portion 13c. Thus, the light emitting devices 10 and 60 having a configuration that can be flexibly applied to various light emitting devices and a configuration for increasing the light extraction efficiency can be provided simply and inexpensively.

  The manufacturing method of the light emitting device 40 includes a step of arranging a plurality of light emitting elements 42 on the upper surface of the substrate base material at intervals, covering each of the light emitting elements 42 with a sealing body 45, and a light extraction surface of the sealing body 45. A step of providing the concavo-convex structure sheet 20 so as to cover at least a portion of 45A and at least a portion of the second frame upper surface 47A, and a step of obtaining a plurality of light emitting devices by cutting the substrate base material. Accordingly, the light emitting device 40 having a configuration that can be flexibly applied to various light emitting devices and a configuration for increasing the light extraction efficiency can be provided simply and inexpensively.

  In the method for manufacturing the light emitting device 40, it is preferable that an external connection terminal is provided on the upper surface of the substrate base material, and the concavo-convex structure sheet 20 has a hole for exposing the external connection terminal. Is preferred. Thereby, external power can be supplied to the light emitting element 42.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  10, 40, 60 Light-emitting device, 11 package, 12, 42 Light-emitting element, 12a 1st terminal, 12b 2nd terminal, 13a, 43a 1st electrode, 13b, 43b 2nd electrode, 13c Connection part, 14a, 44a 1st Bonding wire, 14b, 44b Second bonding wire, 15, 45 Sealed body, 15A, 45A Light extraction surface, 16 Recessed portion, 17 First frame body portion, 17A Upper surface of first frame body, 20 Uneven structure sheet, 21 Uneven surface Structure, 21A Convex part, 21B Concave part, 23 First sheet member, 25 Sheet base material, 27 Second sheet member, 31 Adhesive layer, 41 Substrate, 41A Upper surface, 47 Second frame part (dam ring), 47A Second Upper surface of frame (upper surface of dam ring), 111 package base material, 113a first external connection terminal, 113b second external connection terminal.

Claims (7)

A package having a recess provided on the upper surface and a first frame body surrounding the recess;
A light emitting device provided in the recess,
A sealing body provided in the recess and covering the light emitting element;
With an uneven structure sheet having an uneven structure on the upper surface,
The concavo-convex structure sheet is a light emitting device that covers at least a part of a light extraction surface of the sealing body and at least a part of an upper surface of the first frame body part.   The light emitting device according to claim 1, wherein the package has an external connection terminal on at least one of a side surface and a lower surface. A substrate,
A light emitting device provided on the upper surface of the substrate;
A sealing body provided on an upper surface of the substrate and covering the light emitting element;
A second frame body portion provided on an upper surface of the substrate and surrounding the sealing body;
With an uneven structure sheet having an uneven structure on the upper surface,
The concavo-convex structure sheet is a light emitting device that covers at least a part of a light extraction surface of the sealing body and at least a part of an upper surface of the second frame body part. External connection terminals are provided on the upper surface of the substrate,
The light-emitting device according to claim 3, wherein the concavo-convex structure sheet covers at least a part of an upper surface of the substrate and exposes the external connection terminals. Preparing a package base material having a plurality of packages and a connecting portion for connecting the packages;
Providing a light emitting element in the recess of the package and covering the light emitting element with a sealing body;
Providing a concavo-convex structure sheet so as to cover at least a part of the light extraction surface of the sealing body and at least a part of the upper surface of the first frame body part surrounding the hollow part;
And a step of obtaining a plurality of light emitting devices by cutting the connecting portion. Arranging a plurality of light emitting elements on the upper surface of the substrate base material at intervals, and covering each of the light emitting elements with a sealing body;
Providing a concavo-convex structure sheet so as to cover at least a part of the light extraction surface of the sealing body and at least a part of the upper surface of the second frame body portion surrounding the sealing body;
And a step of obtaining a plurality of light emitting devices by cutting the substrate base material. External connection terminals are provided on the upper surface of the substrate base material,
The method for manufacturing a light emitting device according to claim 6, wherein a hole for exposing the external connection terminal is formed in the uneven structure sheet.

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