JP2007317815A - Light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device for preventing emission characteristics from deteriorating due to the sagging or crawling of resin. <P>SOLUTION: The light-emitting device has a package 1 having a recess 11 that is open in a rectangular shape on a surface, wherein an LED chip 2 is mounted into the recess 11 and a phosphor sheet 3 is provided so that the recess 11 is covered. In the light-emitting device, a step part 12 is provided at the open edge of the recess 11, the peripheral part of the phosphor sheet 3 is placed on the bottom surface of the step part 12 and is stuck via a sticking resin 5, and a reservoir 31 for accumulating the surplus of the sticking resin 5 is provided at the periphery of the phosphor sheet 3 in a groove shape while penetrating in the thickness direction of the phosphor sheet 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting device in which an LED chip and a phosphor are mounted on a package.

  Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 2005-244075 (Patent Document 1), a light emitting device in which an LED chip and a phosphor sheet are mounted on a package is known. As shown in FIG. 6, the light emitting device includes an LED chip 92 mounted on the bottom surface of the recess 93 of the package 91, and a step 94 provided on the periphery of the recess 93. A phosphor sheet 95 is fixed to the stepped portion 94 via a fixing resin.

Therefore, since the phosphor sheet 95 is held on the side surface of the step portion 94 while being placed on the step portion 94, the phosphor sheet 95 is fixed to the step portion 94 without being displaced.
JP-A-2005-244075

  On the other hand, the LED chip 92 has recently been increased in size with the increase in luminance, and it is necessary to use a sealing resin having a relatively low viscosity in order to relieve stress on the enlarged chip. However, also in the fixing resin, when a resin having the same viscosity as that of the sealing resin is used, the fixing force is not sufficient, so that it is necessary to increase the application amount of the fixing resin.

  However, in the conventional light emitting device, in particular, when a large amount of resin having a low viscosity is applied to the stepped portion, the phosphor sheet 95 is placed so that the fixing applied to the stepped portion 94 is performed. The resin hangs down from the step portion 94 to the bottom surface side of the recess 93, or rises from the step portion 94 to the outside of the recess portion 93 or the upper surface of the phosphor sheet 95, causing a problem that the light emission characteristics of the light emitting device deteriorate.

  The present invention has been invented in view of the above-described background art, and an object thereof is to provide a light-emitting device that prevents deterioration of light-emitting characteristics due to dripping or creeping up of a resin.

  In order to solve the above-mentioned problems, the invention according to claim 1 of the present application includes a package having a concave portion opened in a rectangular shape on the surface, an LED chip is mounted in the concave portion, and a phosphor sheet is provided so as to cover the concave portion. A step portion is provided at the opening edge of the concave portion, and the phosphor sheet has a peripheral portion placed on and fixed to the bottom surface of the step portion via a resin. The peripheral portion of the body sheet is provided with a reservoir recess for storing the excess resin.

  The invention according to claim 2 of the present invention is characterized in that, in the light emitting device according to claim 1, the reservoir recess is provided in a groove shape penetrating in the thickness direction of the phosphor sheet.

  Further, in the invention according to claim 3 of the present application, in the light emitting device according to claim 1, the reservoir recess is provided on a side surface of the phosphor sheet, and the phosphor sheet is stepped by the resin accumulated in the reservoir recess. It is characterized by being pressed down to the bottom of the.

  Further, in the invention according to claim 4 of the present application, in the light emitting device according to any one of claims 1 to 3, the bottom surface of the step portion is provided with a reservoir groove portion in which the excess amount of the resin is accumulated. It is a feature.

  In the light emitting device according to the first aspect of the present invention, the peripheral portion of the phosphor sheet is provided with a reservoir recess for storing excess resin. Therefore, the excess resin applied to the step portion accumulates and escapes to the concave portion, so that it drops from the step portion to the bottom surface side of the concave portion, or crawls up from the step portion to the outside of the concave portion or the top surface of the phosphor sheet. It is possible to prevent the light emission characteristics of the light emitting device from deteriorating. Further, since the phosphor sheet is mounted and fixed on the bottom surface of the step portion, the phosphor sheet is held by regulating the side surface of the step portion and can be fixed without being displaced.

  Moreover, in the light emitting device according to claim 2, since the reservoir recess is formed in a groove shape penetrating in the thickness direction of the phosphor sheet, the excess resin is allowed to escape into the reservoir recess and the phosphor sheet. The adhesion area of the resin in the resin can be increased, and the fixing force can be increased.

  Further, in the light emitting device according to claim 3, since the reservoir recess is provided on the side surface of the phosphor sheet, the excess resin is allowed to escape to the reservoir recess, and the phosphor accumulates in the reservoir recess. The sheet is pressed onto the bottom surface of the stepped portion, and the fixing force of the phosphor sheet can be further increased.

  Further, in the light emitting device according to claim 4 of the present invention, since the reservoir groove portion in which the surplus resin is accumulated is provided on the bottom surface of the step portion, the surplus resin can be accumulated and escaped to the groove portion.

  1 and 2 show a light emitting device according to a first embodiment corresponding to claims 1 and 2 of the present application. This light-emitting device is a light-emitting device including a package 1 having a concave portion 11 having a rectangular opening on the surface, an LED chip 2 mounted in the concave portion 11, and a phosphor sheet 3 provided so as to cover the concave portion 11. A step 12 is provided at the opening edge of the recess 11. In addition, the phosphor sheet 3 has its peripheral portion mounted on and fixed to the bottom surface of the step portion 12 via the fixing resin 5, and the phosphor sheet 3 has a peripheral direction in the thickness direction of the phosphor sheet 3. A reservoir recess 31 is provided in the shape of a groove penetrating through the recess.

  Hereinafter, the light-emitting device of this embodiment will be described in more detail. As shown in FIGS. 1 and 2, the package 1 of the light emitting device has a rectangular parallelepiped shape of about 5 to 8 mm square made of ceramic or the like, and has a concave portion 11 opened in a rectangular shape. A step 12 is formed at the periphery of the recess 11, and the center side of the recess 11 opens in a deeper circle from the step 12, and the opening becomes narrower toward the bottom.

  The bottom surface of the recess 11 is a mounting surface 14 provided with chip connection electrodes and the like, and the LED chip 2 is mounted on the mounting surface 14. The LED chip 2 is formed of, for example, a gallium nitride-based semiconductor compound material (GaN, InGaN) that emits blue light, and a plurality of such LED chips 2 may be provided on the mounting surface 14. The mounted LED chip 2 is sealed with a low-viscosity transparent sealing resin 4 such as an epoxy resin or a silicone resin.

  The light emitting device also includes a phosphor sheet 3 formed of a resin mixed with phosphor particles, a glass substrate, or the like. For example, a part of blue light emitted from the LED chip 2 is phosphor sheet. By being converted into yellow light by 3, white light is emitted from the light emitting device. In the peripheral portion of the phosphor sheet 3, four groove-like reservoir recesses 31 that are substantially parallel to the four sides of the phosphor sheet 3 and penetrate in the thickness direction of the phosphor sheet 3 are provided. Further, the thickness of the phosphor sheet 3 used here is about 0.5 mm, but is not particularly limited to this thickness. The thickness of the phosphor sheet 3 is such that an excessive amount of the fixing resin 5 can escape to the accumulation recess 31. It only has to have. Further, the phosphor sheet 3 is fixed so as to be placed on the bottom surface of the step portion 12 to which the fixing resin 5 is applied in advance, and the fixing resin 5 is a low-viscosity resin made of the same material as the sealing resin 4. Is used.

  Next, the manufacturing process of this light emitting device will be described. First, the LED chip 2 is mounted on the mounting surface 14 by being connected to a chip connection electrode or the like provided on the mounting surface 14. Then, the mounted LED chip 2 is sealed with the sealing resin 4, and the fixing resin 5 is applied to the bottom surface of the stepped portion 12. Since the fixing resin 5 is a low-viscosity resin made of the same material as the sealing resin 4, it is applied in a large amount to supplement the fixing force. Finally, the phosphor sheet 3 is placed on the step portion 12 to which the fixing resin 5 is applied, and the fixing resin 5 and the sealing resin 4 are thermally cured. Here, when the phosphor sheet 3 is placed, the surplus of the fixing resin 5 is pushed out to the phosphor sheet 3 and escapes to the accumulation recess 31 provided in the peripheral portion of the phosphor sheet 3. Yes.

  Therefore, in the light emitting device of this embodiment, the peripheral portion of the phosphor sheet 3 is provided with a pool recess 31 in which the excess of the fixing resin 5 is accumulated, and the excess fixing resin applied to the stepped portion 12. Since 5 is accumulated and escapes to the recessed portion 31, it drops from the step portion 12 toward the bottom surface of the recessed portion 11, or crawls up from the step portion 12 to the outside of the recessed portion 11 or the upper surface of the phosphor sheet 3. Can be prevented from deteriorating. Moreover, since the accumulation recessed part 31 penetrates in the thickness direction of the fluorescent substance sheet 3, and is provided in groove shape, the adhesion area of the fixing resin 5 in the fluorescent substance sheet 3 increases, and it can raise the adhering force.

  Further, since the phosphor sheet 3 is mounted and fixed on the bottom surface of the step portion 12, the phosphor sheet 3 is held by being regulated to the side surface of the step portion 12, and can be fixed without being displaced.

  Moreover, since the sealing resin 4 uses a low-viscosity resin, the influence of stress on the LED chip 2 can be suppressed. Therefore, even when a relatively large LED chip 2 is sealed, the LED chip 2 can be effectively sealed without causing a problem that the LED chip 2 is peeled off. Furthermore, since the fixing resin 5 is made of the same material as that of the sealing resin 4, it can be applied in the same process as the sealing resin 4, and the production process can be shortened.

  FIG. 3 shows a light emitting device according to a second embodiment corresponding to claims 1 and 2 of the present application. Here, only matters different from those in the first embodiment will be described, and other matters (configuration, operational effects, and the like) are the same as those in the first embodiment, and the description thereof will be omitted. In the package 1 of the light emitting device, the bottom surface of the step portion 12 is inclined so that the step portion 12 becomes deeper outward from the center side. In this light emitting device, a condensing lens 6 is mounted on the LED chip 2 instead of the sealing resin 4 and fixed.

  Therefore, in the light emitting device of this embodiment, the bottom surface of the stepped portion 12 is inclined so that the stepped portion 12 becomes deeper outward from the center side of the recessed portion 11, and therefore, the fixing resin applied to the stepped portion 12. 5 easily gathers on the outer side of the stepped portion 12, so that the excess fixing resin 5 can be more difficult to hang from the stepped portion 12.

  FIG. 4 shows a light emitting device according to a third embodiment corresponding to claims 1 and 3 of the present application. Here, only matters different from those in the first embodiment will be described, and other matters (configuration, operational effects, and the like) are the same as those in the first embodiment, and the description thereof will be omitted.

  The phosphor sheet 3 of the light emitting device is provided with a concave portion 31 that accumulates in a V-groove shape over the entire side surface. When the fixing resin 5 accumulates in the accumulation recess 31, the phosphor sheet 3 is pressed onto the bottom surface of the stepped portion 12.

  Therefore, in the light emitting device according to this embodiment, since the concave portion 31 is provided on the side surface of the phosphor sheet 3, an excess of the fixing resin 5 is allowed to escape to the residual concave portion 31 and is fixed to the residual concave portion 31. With the resin 5, the phosphor sheet 3 is pressed onto the bottom surface of the stepped portion 12, and the fixing force of the phosphor sheet 3 can be further increased.

  FIG. 5 shows a light emitting device according to a fourth embodiment corresponding to claims 1, 3, and 4 of the present application. Here, only matters different from those in the first embodiment will be described, and other matters (configuration, operational effects, and the like) are the same as those in the first embodiment, and the description thereof will be omitted.

  This light emitting device is provided with a concavity 31 that is cut off from the upper surface to the side surface, leaving only the lower end 32 at the peripheral edge of the phosphor sheet 3. When the fixing resin 5 accumulates in the accumulation recess 31, the phosphor sheet 3 is pressed onto the bottom surface of the stepped portion 12. A collecting groove 13 is provided on the outer side of the bottom surface of the step portion 12 over the entire periphery of the step portion 12.

  Therefore, in the light emitting device of this embodiment, since the accumulation recess 31 is provided so as to be cut off from the side surface to the upper surface in the peripheral portion of the phosphor sheet 3, the excess amount of the fixing resin 5 is accumulated and escapes to the recess 31. At the same time, the phosphor sheet 3 is pressed onto the bottom surface of the stepped portion 12 by the resin accumulated in the accumulation recess 31, and the fixing force of the phosphor sheet 3 can be further increased. Furthermore, in the manufacturing process, after the phosphor sheet 3 is placed on the bottom surface of the stepped portion 12 to which the fixing resin 5 is applied, the fixing resin 5 can be collected again and applied to the concave portion 31 as necessary. The body sheet 3 is more securely fixed.

  In addition, since the accumulation groove 13 is provided on the bottom surface of the stepped portion 12, the excess fixing resin 5 can be released to the accumulation groove 13. By sandwiching the lower end portion 32 of the phosphor sheet 3 by 5, the fixing force of the phosphor sheet 3 can be further enhanced.

  In addition, the accumulation groove part 13 provided in the light-emitting device of this embodiment can be provided also in the light-emitting device of other embodiment.

The top view which shows the light-emitting device which is 1st embodiment of this invention. Sectional drawing which shows the light-emitting device. Sectional drawing which shows the light-emitting device which is 2nd embodiment of this invention. Sectional drawing which shows the light-emitting device which is 3rd embodiment of this invention. Sectional drawing which shows the light-emitting device which is 4th embodiment of this invention. Sectional drawing which shows the light-emitting device which is a prior art example.

Explanation of symbols

1 Package, recess, step, pool groove 2 LED chip 3 phosphor sheet
31 Reservoir recess

Claims (4)

  A light-emitting device that includes a package having a rectangular opening on the surface, in which an LED chip is mounted and a phosphor sheet is provided so as to cover the depression, and a step is provided at the opening edge of the depression The phosphor sheet is provided with a peripheral portion thereof placed on and fixed to the bottom surface of the stepped portion via a resin, and in the peripheral portion of the phosphor sheet, a reservoir recess in which an excess of the resin accumulates. A light emitting device comprising:   The light-emitting device according to claim 1, wherein the accumulation concave portion is provided in a groove shape penetrating in a thickness direction of the phosphor sheet.   2. The light emitting device according to claim 1, wherein the reservoir recess is provided on a side surface of the phosphor sheet, and the phosphor sheet is pressed onto the bottom surface of the step portion by the resin stored in the reservoir recess. .   The light emitting device according to any one of claims 1 to 3, wherein a bottom surface of the step portion is provided with a storage groove portion in which an excess amount of the resin is stored.

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