JP2008085113A - Light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device capable of preventing the light taking-out efficiency from degrading while employing thin profile, even if an element other than a light emitting element is mounted on a substrate. <P>SOLUTION: The light emitting device includes an insulating substrate 11 on which a wiring pattern is formed, with a first substrate 11a and a second substrate 11b being laminated, a light emitting element 12 mounted on the first substrate 11a, and a zener diode 13 which is mounted on the second substrate 11b. The second substrate 11b is formed wider than the first substrate 11a by such area as the zener diode 13 can be mounted, forming a housing part 116 for housing the zener diode 13. Since the zener diode 13 is housed in the housing part 116, the light emitted sideways from the light emitting element 12 is prevented from being obstructed by the zener diode 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting device in which a light emitting element and another element are mounted on a substrate.

In addition to a light emitting element that emits light, the light emitting device may be provided with an element that functions as a bypass capacitor or a Zener diode in order to protect the light emitting element from static electricity or the like. For example, Patent Document 1 describes a composite light emitting element in which a light emitting element is mounted on a submount element that functions as a pass capacitor or a Zener diode.
JP 2003-60243 A

  However, when the light-emitting element is mounted on the submount element as in the composite light-emitting element described in Patent Document 1, the height of the light-emitting device is increased, which satisfies the demand for thinning. Can not. In addition, as light emitting devices are required to have high luminance, light emitting elements having a wide light emitting area have been developed, and it is difficult to mount them on submount elements. Therefore, when an element intended to protect against static electricity such as a submant element is provided in the light emitting device, it is disposed at a side position close to the light emitting element.

  However, since the light emitting element emits light so as to spread from the light emitting surface to the entire periphery, if other elements are arranged on the side of the light emitting element, the light emitted from the light emitting element to the side is obstructed and the light of the light emitting device. The extraction efficiency is reduced.

  Accordingly, an object of the present invention is to provide a light emitting device capable of preventing a decrease in light extraction efficiency while reducing the thickness even when other elements other than the light emitting elements are mounted on a substrate.

  The light emitting device of the present invention includes a substrate on which a wiring pattern is formed, a light emitting element mounted on the substrate and one or more other elements, and the substrate has a height equal to or higher than the height of the other elements. A storage portion having a depth and storing the other element is formed on the inner bottom surface.

  In the light emitting device of the present invention, light from the light emitting element is emitted so as to spread to the surroundings without being blocked by other elements accommodated in the accommodating portion, so that a reduction in light extraction efficiency can be prevented. In addition, since the other elements are mounted on the substrate in a state of being stored in the storage portion, the thickness of the light emitting device is not affected, so that the thickness can be reduced.

  1st invention of this application is equipped with the board | substrate with which the wiring pattern was formed, the light emitting element mounted on the board | substrate, and one or more other elements, The depth more than the height of another element in a board | substrate And a housing portion in which another element is housed is formed on the inner bottom surface.

  In the light emitting device of the present invention, a light emitting element and one or more other elements are mounted on a substrate. The substrate is formed with a storage portion having a depth greater than the height of other elements and accommodating other elements on the inner bottom surface. Accordingly, the light from the light emitting element is emitted so as to spread to the surroundings without being obstructed by other elements accommodated in the accommodating portion, so that it is possible to prevent the light extraction efficiency from being lowered. In addition, since the other elements are mounted on the substrate in a state of being stored in the storage portion, the thickness of the light emitting device is not affected, so that the thickness can be reduced.

  2nd invention of this application is resin containing the fluorescent substance which is excited by the light from a light emitting element, and wavelength-converts, The resin sealing part which sealed the light emitting element and one or more other elements is provided, The light emitting element is arranged at the center of the substrate, and the resin sealing portion is formed so that the distance to the surface facing the light emitting surface of the light emitting element is equal.

  Since the resin sealing portion contains a phosphor, the light of the light emitting device is a mixture of light that is excited by the light from the light emitting element and wavelength-converted and the light as it is from the light emitting element. Become. By forming the resin sealing portion so that the distance to the surface facing the light emitting surface of the light emitting element is equal, the distance passing through the resin sealing portion can be equal. Therefore, since the degree of light whose wavelength is converted by passing becomes the same on each surface of the resin sealing portion, it is possible to prevent color unevenness.

  The third invention of the present application is characterized in that the depth of the storage portion is substantially the same as the height of the other elements.

  By making the depth of the storage portion substantially the same as the height of the other elements, the upper surfaces of the other elements stored in the storage portion are substantially at the same position as the mounting surface of the substrate on which the light emitting elements are mounted. Therefore, the light emitted from the light emitting element to the side can be efficiently reflected on the upper surface of another element.

  A fourth invention of the present application is characterized in that a reflection part for reflecting light from the light emitting element is formed on an upper surface of another element housed in the housing part.

  By providing the reflective portion on the upper surface of another element, light from the light emitting element can be further efficiently reflected, so that light extraction efficiency can be improved.

  The fifth invention of the present application is characterized in that the other element is connected to each of the anode and the cathode of the light emitting element and has a function of bypassing static electricity to the light emitting element.

  By providing other elements with a function of bypassing static electricity to the light emitting elements, the static electricity is emitted when the light emitting device of the present invention is transported or mounted on a mounting board. It can be protected even if it is applied to.

(Embodiment 1)
A light-emitting device according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing a light emitting device according to Embodiment 1 of the present invention. FIG. 2 is a plan view of the light-emitting device shown in FIG.

  As shown in FIG. 1 and FIG. 2, the light emitting device 10 includes an insulating substrate 11 on which a light emitting element 12 and a Zener diode 13 other than the light emitting element 12 are mounted and sealed by a resin sealing portion 14. It has been stopped.

  The insulating substrate 11 is a white alumina ceramic substrate and is formed in a rectangular shape in plan view. On the insulating substrate 11, a wiring pattern 110 for conducting and mounting the light emitting element 12 and the Zener diode 13 is formed on the mounting surface side on which the light emitting element 12 is mounted. The wiring pattern 110 includes a first wiring pattern 111 that connects the anode of the light emitting element 12 and one electrode of the bypass capacitor, and a second wiring pattern 112 that connects the cathode and the other electrode of the Zener diode 13. is doing. The first wiring pattern 111 and the second wiring pattern 112 are connected via a first electrode 113, a second electrode 114, and a through-hole electrode 115 formed on the back surface side of the insulating substrate 11.

  The insulating substrate 11 is formed with a storage portion 116 on which the Zener diode 13 is mounted, which is one step lower than the mounting surface on which the light emitting element 12 is mounted. The storage portion 116 includes a first substrate 11a having a mounting surface on which the light emitting element 12 is mounted, and a second substrate formed wider than the first substrate 11a only in the mounting surface area on which the Zener diode 13 is mounted than the first substrate 11a. 11b is bonded together. The thickness of the first substrate 11 a is substantially the same as the height of the Zener diode 13. That is, the depth of the storage portion 116 is substantially the same as the height of the Zener diode 13. The term “substantially the same” includes even if the height of the Zener diode 13 and the thickness of the first substrate 11a have a difference of about a manufacturing error. That is, it is included except when the height of the Zener diode 13 and the thickness of the first substrate 11a are intentionally different sizes.

  In the insulating substrate 11 according to the first embodiment, the storage portion 116 is formed by bonding the first substrate 11a and the second substrate 11b having different sizes, but one insulating substrate is cut. You may make it form. In that case, it is possible to prepare a substrate having the size of the second substrate 11b and the total thickness of the first substrate 11a and the second substrate 11b and scrape off the thickness of the first substrate 11a. . Further, the storage portion 116 is formed so as to approach one end portion of the insulating substrate 11. However, the housing portion 116 is bonded to the second substrate in a state where the first insulating substrate is cut out, or the counterbore is attached to one insulating substrate. It can also be set as the recessed part which has a surrounding wall surface part as an accommodating part by giving a process.

  The light emitting element 12 is a blue light emitting element, and an n layer, a light emitting layer, and a p layer, which are compound semiconductor layers, are stacked on a sapphire substrate, an n electrode is formed on the n layer, and a p electrode is formed on the p layer. It is provided as. The light emitting element 12 is connected to the first wiring pattern 111 and the second wiring pattern 112 via bumps 120.

  The Zener diode 13 is connected to the first wiring pattern 111 and the second wiring pattern 112 via bumps 131. The zener diode 13 functions as a reflective part by adopting a material having a metallic luster on the surface, applying a liquid with a high reflectance on the surface and curing it, or attaching a sheet with a high reflectance. It is desirable to let them.

  For example, an epoxy resin can be used for the resin sealing portion 14 and contains a phosphor (not shown). The phosphor emits a complementary color by converting the wavelength of light from the light emitting element 12. In the first embodiment, the light emitting element 12 that emits blue light is used, and the phosphor that converts the wavelength to yellow is used. Therefore, the surface of the resin sealing portion 14 is a light emitting element. The blue color from 12 and the yellow color after wavelength conversion are mixed to become white.

  The usage state of the light emitting device 10 according to the first embodiment of the present invention configured as described above will be described with reference to FIGS. 1 and 2.

  First, a positive voltage is applied to the first electrode 113 and a negative voltage is applied to the second electrode 114. By applying a voltage to the first electrode 113 and the second electrode 114, a current flows through the light emitting element 12 through the through-hole electrode 115, the first wiring pattern 111, and the second wiring pattern 112. The blue light emitted from the light emitting element 12 is mixed with the light that excites the phosphor of the resin sealing portion 14 and the light that passes through it to become white. And since the insulating substrate 11 is made into the white alumina ceramic substrate, the light from the side of the light emitting element 12 can be reflected efficiently. Further, the light that has passed above the Zener diode 13 stored in the storage unit 116 is emitted from the side surface of the resin sealing unit 14. Therefore, even if the Zener diode 13 other than the light emitting element 12 is mounted on the insulating substrate 11, the light from the side of the light emitting element 12 is not hindered, so that a decrease in light extraction efficiency can be prevented.

  Further, since the Zener diode 13 does not have the light emitting element 12 mounted on the upper surface of the Zener diode 13, the thickness from the first substrate 11a to the upper surface of the resin sealing portion 14 can be reduced. Therefore, even if the Zener diode 13 other than the light emitting element 12 is mounted on the insulating substrate 11, the thickness of the entire light emitting device 10 can be reduced, and thus the thickness reduction can be improved.

  Note that if the depth of the storage portion 116 is deeper than the height of the Zener diode 13, the light from the side of the light emitting element 12 is not inhibited by storing the Zener diode 13 in the storage portion 116. However, if it is deeper than the height of the Zener diode 13, light from the side of the light emitting element 12 becomes difficult to reach the entire upper surface of the Zener diode 13, so that the amount of reflection by the upper surface of the Zener diode 13 is reduced and the light extraction efficiency is improved. descend. Therefore, it is desirable that the depth of the storage portion 116 is the same as the height of the Zener diode 13. That is, it is desirable that the thickness of the first substrate 11a is the same as the height of the Zener diode 13.

  Further, since the Zener diode 13 is connected in parallel with the light emitting element 12, it is possible to bypass noise that rises sharply such as static electricity. Therefore, the light emitting element 12 can be protected from static electricity. Furthermore, since the surface of the Zener diode 13 functions as a reflecting portion, the light emitted from the side of the light emitting element 12 can be efficiently reflected.

  In the present embodiment, the Zener diode 13 is connected as an element for protecting the light emitting element 12, but a bypass capacitor may be used.

(Embodiment 2)
A light emitting device according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view showing a light-emitting device according to Embodiment 2 of the present invention. FIG. 4 is a plan view of the light-emitting device shown in FIG. 3 and FIG. 4, the same components as those in FIG. 1 and FIG.

  As shown in FIGS. 3 and 4, the light emitting device 20 according to the second embodiment of the present invention has the light emitting element 12 arranged at the center of an insulating substrate 21. The resin sealing portion 22 is formed of a resin containing a phosphor similarly to the resin sealing portion 14 of the first embodiment, and is formed in the same square shape as the insulating substrate 21 in plan view. That is, since the light emitting element 12 is disposed in the central portion of the insulating substrate 21, the four side surfaces 121 to 124 of the light emitting element 12 and the four side surfaces 221 to 224 of the resin sealing portion 22 facing each other are disposed. The distance is assumed to be equidistant. In addition, the distance between the upper surface 125 of the light emitting element 12 and the upper surface 225 of the resin sealing portion 22 facing the upper surface 125 is also equal.

  As in the first embodiment, the insulating substrate 21 has a mounting surface on which the light emitting element 12 is mounted, a first substrate 21a having the same thickness as the height of the Zener diode 13, and a Zener than the first substrate 21a. Only the region of the mounting surface on which the diode 13 is mounted is formed by bonding the second substrate 21b formed wider than the first substrate 21a. In this way, by attaching the first substrate 21a to the second substrate 21b, a storage portion 212 that stores the Zener diode 13 that is one step lower than the mounting surface on which the light emitting element 12 is mounted is formed. Therefore, even if the Zener diode 13 is provided in the light emitting device 20, the light from the side of the light emitting element 12 is not obstructed because it is accommodated in the accommodating portion 212. In addition, since the depth of the storage portion 212 is the same as the height of the Zener diode 13, the light from the side of the light emitting element 12 is reflected on the upper surface of the Zener diode 13 and from the side surface 223 of the resin sealing portion 22. The light can be emitted efficiently.

  Next, a method for manufacturing the light emitting device 20 will be described with reference to FIG. FIG. 5 shows a method for manufacturing the light emitting device according to Embodiment 2 of the present invention. In FIG. 5, since the light emitting elements 12 are illustrated in a single row arrangement as viewed from the front, the light emitting elements 12 are also arranged in the depth direction so that they are arranged in a matrix. .

  As shown in FIGS. 3 to 5, when manufacturing the light emitting device 20, first, the first substrates 21 a are arranged and bonded to the substrate material 23 to be the second substrate 21 b in the vertical and horizontal rows. Next, the through-hole electrode 115, the first wiring pattern 111, the second wiring pattern 112, the first electrode 113, and the second electrode 114 are formed at predetermined positions. Next, the light emitting element 12 and the Zener diode 13 are respectively arranged. And the resin layer 24 used as the resin sealing part 22 is formed by clamping with a metal mold | die. The thickness of the resin layer 24 is formed such that the distance between the side surfaces 121 to 124 of the light emitting element 12 and the side surfaces 221 to 224 of the resin sealing portion 22 when they are later separated into pieces is equal. The resin layer 24 can also be formed by a screen printing method.

  And the board | substrate material 23 is cut | disconnected for every cutting line C with a dicer, and it is set as the light-emitting device 20 shown in FIG. 3 and FIG.

  Here, the equidistance includes a difference in error when forming the resin layer 24 shown in FIG. 5 and a difference in error when dicing along the cutting line C. That is, intentionally different distances from the respective light emitting surfaces (side surfaces 121 to 124 and the upper surface 125) of the light emitting element 12 to the respective surfaces (side surfaces 221 to 224 and the upper surface 225) of the resin sealing portion 22 facing the respective surfaces. Included except.

  By manufacturing the light emitting device 20 in this way, the resin sealing portion 22 is not only formed in the same square shape as the insulating substrate 21 in plan view, but also the side surface 221 of the resin sealing portion 22 with respect to the insulating substrate 21. ˜224 can be the vertical plane.

  That is, each light emitting surface (side surfaces 121 to 124 and upper surface 125) of the light emitting element 12 and each surface (side surfaces 221 to 224 and upper surface 225) of the resin sealing portion 22 facing each surface are parallel. The distance between them is equidistant. Therefore, since the distance that light directly reaches from each surface of the light emitting element 12 to each surface of the resin sealing portion 22 becomes equal, the degree of light whose wavelength is converted by the phosphor by passing through can be made the same. it can.

  Since the depth of the storage portion 212 is the same as the height of the Zener diode 13, the position of the upper surface of the Zener diode 13 and the position of the mounting surface of the first substrate 21a are the same height. Therefore, the light that once reflects from the side surfaces 121, 122, and 124 except the side surface 123 of the light emitting element 12 to the first substrate 21a and reaches the side surfaces 221, 222, and 224 except the side surface 223 of the resin sealing portion 22, and the light emitting element The degree of the wavelength conversion of the phosphors by the light traveling from the side surfaces 123 of the twelve side surfaces 123 to the upper surface of the Zener diode 13 and reaching the side surfaces 223 of the resin sealing portion 22 may be the same. it can.

  Therefore, uneven color of light emitted from each surface (side surfaces 221 to 224 and upper surface 225) of the resin sealing portion 22 can be prevented.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, the light emitting devices 10 and 20 protect the light emitting elements 12 from static electricity as other elements. Although the Zener diode 13 is mounted, it may be a Zener diode, a resistor for limiting the current, or a control IC (Integrated Circuit) having other functions.

  Even if a plurality of other elements are mounted, there is no problem because the light does not hinder the light if it is stored in the storage section. Further, even when a plurality of light emitting elements are mounted, the same effect can be obtained by storing other elements in the storage portion.

  In the present invention, even when other elements than the light emitting element are mounted on the substrate, it is possible to prevent the light extraction efficiency from being lowered while reducing the thickness. It is suitable for a mounted light emitting device.

Sectional drawing which shows the light-emitting device which concerns on Embodiment 1 of this invention. FIG. 1 is a plan view of the light emitting device shown in FIG. Sectional drawing which shows the light-emitting device concerning Embodiment 2 of this invention. FIG. 3 is a plan view of the light emitting device shown in FIG. The figure which shows the manufacturing method of the light-emitting device which concerns on Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Light-emitting device 11 Insulating substrate 11a 1st board | substrate 11b 2nd board | substrate 110 Wiring pattern 111 1st wiring pattern 112 2nd wiring pattern 113 1st electrode 114 2nd electrode 115 Through-hole electrode 116 Storage part 12 Light emitting element 120 Bump 121-124 Side surface 125 Upper surface 13 Zener diode 131 Bump 14 Resin sealing portion 20 Light emitting device 21 Insulating substrate 21a First substrate 21b Second substrate 212 Storage portion 22 Resin sealing portions 221 to 224 Side surface 225 Upper surface 23 Substrate material 24 Resin layer

Claims (5)

A substrate on which a wiring pattern is formed;
A light emitting device mounted on the substrate and one or more other devices,
The light emitting device according to claim 1, wherein the substrate has a depth greater than or equal to the height of the other element, and a storage portion in which the other element is stored is formed on an inner bottom surface. A resin-sealed portion that seals the light-emitting element and the one or more other elements with a resin containing a phosphor that is excited by light from the light-emitting element to convert the wavelength,
The light emitting device according to claim 1, wherein the resin sealing portion is formed so as to be equidistant from a surface facing the light emitting surface of the light emitting element. The light emitting device according to claim 1, wherein a depth of the storage portion is substantially the same as a height of the other element. The light emitting device according to any one of claims 1 to 3, wherein a reflection portion that reflects light from the light emitting element is formed on an upper surface of the other element housed in the housing portion. apparatus. 5. The device according to claim 1, wherein the other element is connected to each of an anode and a cathode of the light emitting element and has a function of bypassing static electricity to the light emitting element. Light-emitting device.

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