JP2009194109A - Semiconductor light-emitting element, manufacturing method thereof and illumination apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting element which is easily manufactured at a low cost, and emits a generated light at the maximum light quantity. <P>SOLUTION: The semiconductor light-emitting element 1 includes: a package cup 3 having a recess portion 2 with a lead electrode 6 formed in the inner surface; a semiconductor light-emitting chip 4 disposed in the recess portion 2 of the package cup 3, wherein the semiconductor light-emitting chip 4 includes light-emitting layers 8, 9 stacked in two layers, and the light-emitting layer 9 far from the package cup 3, out of the light-emitting layers 8, 9, is electrically connected to the lead electrode 6 via a through-hole 10 formed so as to penetrate the light-emitting layer 8 near the package cup in the thickness direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor light emitting device, a method for manufacturing the same, and a lighting device.

  Conventionally, in order to reduce the disadvantage that the wire bonded so as to connect the surface of the semiconductor light emitting chip and the lead electrode in the package cup reduces the amount of light generated from the semiconductor light emitting chip, A semiconductor light-emitting device in which wires are arranged so as to pass through corners of a chip is known (for example, see Patent Document 1).

JP 2007-27431 A

  However, in the light emitting device disclosed in Patent Document 1, it is necessary to strictly adjust the wiring track of the semiconductor light emitting chip during positioning and wire bonding, which requires time and cost for adjustment work, and time required for reworking. There is an inconvenience that the yield is bad, such as cost and cost. In addition, the light emitted from the semiconductor light emitting chip is emitted after being diffusely reflected in the resin covering the semiconductor light emitting chip, so that when the wire exists in the resin, the amount of the emitted light is also reduced. There is also.

  The present invention has been made in view of the above-described circumstances, and can be manufactured easily and at low cost, and a semiconductor light emitting element capable of emitting generated light with the maximum amount of light, a manufacturing method thereof, and an illumination device The purpose is to provide.

In order to achieve the above object, the present invention provides the following means.
The present invention includes a package cup having a recess having an inner surface formed with a lead electrode, and a semiconductor light emitting chip disposed in the recess of the package cup, the light emitting layer having the semiconductor light emitting chip laminated in two layers Among the light emitting layers, the light emitting layer far from the package cup is electrically connected to the lead electrode through a through hole formed through the light emitting layer on the near side in the thickness direction. A semiconductor light emitting device is provided.

  According to the present invention, the light emitting layer far from the package cup is electrically connected to the lead electrode in the recess of the package cup through the through hole formed in the light emitting layer near the package cup. Unlike the conventional bonding wire, it is not necessary to have a member that crosses the light emitting portion between the two light emitting layers, and the generated light can be emitted to the outside with the maximum amount of light. In addition, since the wires that block light are not wired, there is no need to perform wiring in consideration of the relative positional relationship between the semiconductor light emitting chip and the wires as in the past, and the positioning of the semiconductor light emitting chip and the adjustment of the wiring track of the wires are not required. Such a complicated adjustment work is unnecessary, and it can be manufactured easily and at low cost.

  In the above invention, the semiconductor light emitting chip includes a SiC substrate, the two light emitting layers are stacked on the surface of the SiC substrate, the SiC substrate is electrically connected to an adjacent light emitting layer, and the package cup. The other light emitting layer is electrically connected to one of the lead electrodes, and the far light emitting layer passes through the light emitting layer on the near side and the SiC substrate through the through hole formed in the thickness direction. It may be electrically connected to the electrode.

  In this way, one of the two light emitting layers can be directly connected to one lead electrode of the package cup via the conductive SiC substrate, and can be manufactured more easily.

Moreover, in the said invention, the back surface of the said SiC substrate may be connected to the said lead electrode by the paste layer containing a metal particle.
In the above invention, the conductive layer provided on the back surface of the SiC substrate with an insulating layer interposed therebetween and electrically connected to the light emitting layer on the far side through the through hole is formed of the metal particle paste with the lead. It may be connected to an electrode.
In the above invention, an anisotropic conductive film or anisotropic conductive paste may be disposed between the lead electrode and the back surface of the SiC substrate and the conductive layer.

  By doing in this way, almost the entire back side of the SiC substrate can be connected to the lead electrode by a paste containing metal particles having good conductivity and thermal conductivity, an anisotropic conductive film or an anisotropic conductive paste, While reducing the electrical resistance of the wiring connected to each light emitting layer, the heat generated in the light emitting layer can be efficiently dissipated to the outside.

  The present invention also includes a step of laminating two light emitting layers on the surface of the SiC substrate, a step of forming a through hole penetrating the light emitting layer and the SiC substrate, an inner surface of the through hole, and the SiC substrate. Forming an insulating layer made of an insulating material on a part of the back surface, and forming a conductive layer made of a conductive material conducting to the light emitting layer on the surface side on the surface of the through hole and the insulating layer; And a step of electrically connecting the back surface of the SiC substrate and the conductive layer to separate lead electrodes in the recesses of the package cup having lead electrodes formed on the inner surface, respectively. provide.

According to the present invention, the light emitting layer on the surface side can be easily electrically connected to the lead electrode in the recess of the package cup through the SiC substrate and the through hole penetrating the light emitting layer, so that wire bonding is unnecessary, and light emission is achieved. A semiconductor light emitting device with high efficiency and power consumption can be manufactured.
Examples of the method for forming the insulating layer include a sputtering method, a vapor deposition method, a printing method, and an insulating thin film sticking method. Examples of the method for forming the conductive layer include sputtering, plating, vapor deposition, printing, and metal thin film pasting.

Moreover, this invention provides an illuminating device provided with one of the said semiconductor light-emitting devices.
According to the present invention, since the maximum amount of light is emitted from the semiconductor light emitting element, illumination with a large amount of light can be performed with low power consumption.

  According to the present invention, there is an effect that it can be manufactured easily and at low cost, and the generated light can be emitted with the maximum amount of light.

A semiconductor light emitting device 1 and a method for manufacturing the same according to an embodiment of the present invention will be described below with reference to FIGS.
As shown in FIGS. 1 and 2, the semiconductor light emitting device 1 according to the present embodiment includes a package cup 3 having a recess 2, a semiconductor light emitting chip 4 mounted in the recess 2 of the package cup 3, And a transparent insulating resin 5 potted in the recess 2 so as to cover the entire surface of the semiconductor light emitting chip 4.

A lead electrode 6 is provided on the inner surface of the recess 2 of the package cup 3. The lead electrode 6 extends through the package cup 3 to the outside.
As shown in FIG. 2, the semiconductor light-emitting chip 4 includes a SiC substrate 7 and two gallium nitride layers (light-emitting layers) 8 of an n-type semiconductor and a p-type semiconductor formed on the surface of the SiC substrate 7, 9 and. A through hole 10 penetrating in the thickness direction is formed in the SiC substrate 7 and the two gallium nitride layers 8 and 9. The through hole 10 can be easily and accurately formed by, for example, the Deep RIE method (Bosch process) or the sand blast method.

An insulating layer 11 and a first conductive layer 12 are laminated on the inner surface of the through hole 10 and the back surface of the SiC substrate 7. A second conductive layer 13 is formed on the surface of the upper gallium nitride layer 9 and the surface of the first conductive layer 12 in the through hole 10.
Examples of the method for forming the insulating layer 11 include a sputtering method, a plating method, a vapor deposition method, a printing method, and an insulating thin film sticking method. Moreover, as a formation method of the conductive layers 12 and 13, a sputtering method, a plating method, a vapor deposition method, a printing method, a metal thin film sticking method, etc. can be mentioned.

As shown in FIG. 3, the insulating layer 11 and the first conductive layer 12 formed on the back surface of the SiC substrate 7 are partially planar on the back surface of the SiC substrate 7 including the periphery of the opening of the through hole 10. Has spread. The first conductive layer 12 is electrically insulated from the SiC substrate 7 by an insulating layer 11 formed between the SiC substrate 7 and the first conductive layer 12. On the other hand, the first conductive layer 12 is formed integrally with the first conductive layer 12 formed in the through hole 10 and is electrically conductive.
On the back surface of the SiC substrate 7 where the insulating layer 11 and the first conductive layer 12 are not formed, an electrode having the same thickness as the total thickness of the insulating layer 11 and the first conductive layer 12 formed on the back surface The conductive layer 15 is electrically insulated from the conductive layer 12.

  The first conductive layer 12 formed in the through hole 10 is formed on the SiC substrate 7 and the two gallium nitride layers 8 and 9 by the insulating layer 11 formed between the inner surface of the through hole 10. It is electrically insulated from it.

  The second conductive layer 13 formed on the surface of the upper gallium nitride layer 9 and the surface of the first conductive layer 12 in the through hole 10 is an upper layer in contact with the second conductive layer 13. The gallium nitride layer 9 and the first conductive layer 12 in the through hole 10 are electrically connected. On the other hand, the second conductive layer 13 is electrically insulated from the underlying gallium nitride layer 8 by the insulating layer 11 formed in the through hole 10.

  In such a semiconductor light emitting chip 4, as shown in FIG. 4, (a) a through-hole 10 is formed in (a) two gallium nitride layers 8 and 9 grown on a SiC substrate 7. (C) an insulating layer 11 is formed in the through-hole 10 and a part of the back surface from the back surface side of the SiC substrate 7; (d) a first conductive layer 12 is formed on the surface of the insulating layer 11; After that, the second conductive layer 13 is formed from the surface side of the upper gallium nitride layer 9 to the surface and the surface of the first conductive layer 12 in the through hole 10.

  The semiconductor light emitting chip 4 manufactured in this way is electrically and mechanically connected to the lead electrode 6 formed on the inner surface of the recess 2 of the package cup 3 using an anisotropic conductive film 14. The anisotropic conductive film 14 is formed with a predetermined thickness over the entire region where the semiconductor light emitting chip 4 is installed on the bottom surface of the recess 2 of the package cup 3.

  By pressing the semiconductor light emitting chip 4 against the anisotropic conductive film 14, the electrode conductive layer 15 and the first conductive layer 12 formed on the back surface of the SiC substrate 7 of the semiconductor light emitting chip 4 are separated from each other by separate lead electrodes 6. It is bonded in a state of electrical conduction. The anisotropic conductive film 14 is electrically conducted only in the direction in which pressure is applied, and the insulating state is maintained in the other directions. Therefore, separate lead electrodes are provided on the two gallium nitride layers 8 and 9. 6 can be easily electrically connected.

  Further, the conductive paste 14 ′ can be used instead of the anisotropic conductive film 14 for electrical and mechanical connection. When the conductive paste 14 'is used, the conductive paste 14' is applied so that the two electrodes formed on the back surface of the SiC substrate 7 are not electrically short-circuited, and as shown in FIG. The seven-part conductive paste 14 'and the first conductive layer 12-part conductive paste 14' are electrically insulated from each other by being arranged with a gap therebetween.

  Since the conductive paste 14 'is electrically connected to the conductive paste 14' in a surface contact with a relatively large area, the heat generated by the semiconductor light emitting chip 4 is efficiently radiated to the lower part of the package cup 3. Is done.

  The transparent resin 5 covering the semiconductor light emitting chip 4 contains a fluorescent substance. Examples of the fluorescent material include yttrium / aluminum garnet oxide phosphor, silicate phosphor, europium activated alkaline earth metal silicate phosphor, and the like. A fluorescent substance may be used independently and may be used in mixture of 2 or more types. Examples of the resin 5 include an epoxy resin and a silicone resin. Further, instead of the resin 5, sol-gel glass may be used.

  According to the semiconductor light emitting device 1 according to the present embodiment configured as described above, the voltage applied to one lead electrode 6 is lower than the anisotropic conductive film 14, the electrode conductive layer 15, and the SiC substrate 7. The gallium nitride layer 8 is added. The voltage applied to the other lead electrode 6 is applied to the upper gallium nitride layer 9 via the anisotropic conductive film 14, the first conductive layer 12 and the second conductive layer 13. As a result, light is emitted between the two gallium nitride layers 8 and 9.

  In this case, since the upper gallium nitride layer 8 and the lead electrode 6 are not connected by the wire, the emitted light is not blocked by the wire, and the emitted light can be emitted to the maximum. That is, the emitted light can be used without waste, the luminous efficiency can be improved, and a bright lighting device (not shown) with low power consumption can be configured.

In addition, since the lead electrode 6 and the gallium nitride layer 9 are not connected by a wire, the wire breaks during heat generation due to light emission depending on the difference in thermal expansion coefficient between the wire and the surrounding resin 5. Can be prevented.
Further, since the lead electrode 6 and the gallium nitride layer 9 are not connected by a wire, the positioning of the semiconductor light emitting chip 4 and the wire are not performed as in the case where the wire is wired so as to pass through the corner of the conventional semiconductor light emitting chip. Strict control of the wiring trajectory is not necessary, and there is an advantage that it can be easily manufactured.

  Further, according to the semiconductor light emitting device 1 according to the present embodiment, the semiconductor light emitting chip 4 can be connected to the lead electrode 6 with a relatively wide area by the silver paste 15 and the anisotropic conductive film 14. As a result, the following effects are obtained.

  That is, the semiconductor light emitting device 1 according to the present embodiment generates heat when light is emitted from between the two gallium nitride layers 8 and 9, but the heat is dissipated to the package cup 3 side through the SiC substrate 7. It will be done. In this case, since the SiC substrate 7 and the package cup 3 are in contact with each other by the silver paste 15 and the anisotropic conductive film 14, heat can be smoothly radiated by a wide heat radiation area without using an air layer. it can.

  Further, as shown in FIG. 7, bumps are provided on the gallium nitride layer, and flip chip bonding in which the bump electrode 16 is connected to the lead electrode of the package cup by inverting the sapphire substrate 7 'and the gallium nitride layer is also performed by a wire. Wiring can be eliminated. However, in this case, when reflow soldering is performed to mount the semiconductor light emitting device 1 on a circuit board (not shown), the gallium nitride is heated from the substrate due to the difference in linear expansion coefficient between the sapphire substrate 7 'and the gallium nitride layer. There is an inconvenience that the ride layer peels off.

  On the other hand, according to the present embodiment, the gallium nitride layers 8 and 9 are connected to the lead electrode 6 in the package cup 3 via the SiC substrate 7 having a low thermal conductivity. There is an advantage that the heat at this time is not directly applied to the gallium nitride layers 8 and 9, and there is no inconvenience of peeling.

  In the present embodiment, the SiC substrate 7 having conductivity is employed as the substrate on which the gallium nitride layers 8 and 9 are grown. Instead, sapphire, diamond, copper diamond, ruby, GaN, BeO, A single crystal or polycrystal such as ZnO, Si, ZnS, Al, Cu, W, or AlN may be employed.

  In the present embodiment, the semiconductor light emitting chip 4 including the SiC substrate 7 is illustrated, but instead of this, as shown in FIG. 5, the gallium nitride layer 8 or 9 is formed and then the substrate is peeled off. The semiconductor light emitting chip 4 ′ composed of the nitride layers 8 and 9 may be installed in the recess 2 of the package cup 3.

  In this case, after the substrate is peeled off, the through-hole 10 penetrating the two gallium nitride layers 8 and 9 is formed in the same manner as described above, and the back surface of the through-hole 10 and the lower gallium nitride layer 8 is formed. An insulating film 11 and a first conductive layer 12 are formed on a part of the first conductive layer 11, and a second conductive layer 13 is formed on the surface of the first conductive layer 11 in the surface of the upper gallium nitride layer 9 and the through hole 10. To do. Then, the back surface of the lower gallium nitride layer 8 is directly electrically connected to one lead electrode 6 in the recess 2 of the package cup 3, and the upper gallium nitride layer 9 is formed in the through hole 10. The other lead electrode 6 may be electrically connected through the first conductive layer 12 and the second conductive layer 13.

It is a longitudinal cross-sectional view which shows the semiconductor light-emitting device concerning one Embodiment of this invention. FIG. 2 is an enlarged longitudinal sectional view in which semiconductor light emitting chips provided in the semiconductor light emitting element of FIG. 1 are connected by an anisotropic conductive film. FIG. 3 is a rear view showing the semiconductor light emitting chip of FIG. 2. FIG. 3 is a process diagram illustrating a method for manufacturing the semiconductor light emitting chip of FIG. 2. FIG. 4 is a longitudinal sectional view showing a modification of the semiconductor light emitting chip in FIG. 2. It is the longitudinal cross-sectional view which connected the semiconductor light-emitting chip with which the semiconductor light-emitting element of FIG. 1 is equipped with the electrically conductive paste. It is a longitudinal cross-sectional view which shows an example of the semiconductor light-emitting chip for flip-chip bonding which provides a bump in a gallium nitride layer, inverts a sapphire substrate and a gallium nitride layer, and connects a bump electrode to the lead electrode of a package cup.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor light emitting element 2 Recessed part 3 Package cup 4,4 'Semiconductor light emitting chip 5 Resin 6 Lead electrode 7 SiC substrate 7' Sapphire substrate 8,9 Gallium nitride layer (light emitting layer)
10 through-hole 11 insulating layer 12 first conductive layer (conductive layer)
13 Second conductive layer (conductive layer)
14 Anisotropic Conductive Film 14 'Conductive Paste 15 Electrode Layer for Electrode 16 Bump Electrode

Claims (7)

A package cup having a recess with a lead electrode formed on the inner surface;
A semiconductor light emitting chip disposed in the recess of the package cup,
The semiconductor light emitting chip has a light emitting layer laminated in two layers,
A semiconductor light-emitting element in which a light-emitting layer far from the package cup is electrically connected to the lead electrode through a through-hole formed through the light-emitting layer on the near side in the thickness direction. The semiconductor light emitting chip includes a SiC substrate, and the two light emitting layers are stacked on the surface of the SiC substrate,
The SiC substrate is electrically connected to the adjacent light emitting layer and electrically connected to one of the lead electrodes of the package cup,
The distant light emitting layer is electrically connected to the other lead electrode through a through hole formed in the thickness direction through the light emitting layer on the near side and the SiC substrate. The semiconductor light emitting element as described.   The semiconductor light emitting element according to claim 2, wherein a back surface of the SiC substrate is connected to the lead electrode by a paste layer containing metal particles.   A conductive layer provided on the back surface of the SiC substrate with an insulating layer interposed therebetween and electrically connected to the light emitting layer on the far side through the through hole is connected to the lead electrode by a paste containing metal particles. The semiconductor light emitting device according to claim 2 or claim 3.   The semiconductor light emitting element according to claim 4, wherein an anisotropic conductive film or an anisotropic conductive paste is disposed between the lead electrode and the back surface of the SiC substrate and the conductive layer. Laminating two light emitting layers on the surface of the SiC substrate;
Forming a through hole penetrating the light emitting layer and the SiC substrate;
Forming an insulating layer made of an insulating material on the inner surface of the through hole and a part of the back surface of the SiC substrate;
Forming a conductive layer made of a conductive material conducting to the light emitting layer on the surface side on the surface of the through hole and the insulating layer;
A method of manufacturing a semiconductor light emitting device, comprising: electrically connecting a back surface of the SiC substrate and the conductive layer to separate lead electrodes in a recess of a package cup having lead electrodes formed on the inner surface.   An illuminating device provided with the semiconductor light emitting element in any one of Claims 1-5.

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