JP3893735B2 - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a composite semiconductor full-color light emitting element to emit light rays of different colors by making the electrical connection of the element easier and improving the breakdown voltage against impressed high voltages of static electricity, surge, etc. SOLUTION: A composite semiconductor full-color light emitting element is constituted by mounting semiconductor light emitting elements 5, 6, and 7 for red, green, and blue in continuity on an Si diode 3 for static electricity protection connected in continuity to a lead frame or substrate. The light emitting elements 6 and 7 for green and blue are used as GaN-containing flip chip light emitting elements and, at the same time, micro-bumps 6d and 6e are formed on the n- and p-side electrodes of the elements 6 and 7 and conducted to the polarity opposite to that of the diode 3.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light-emitting device including a flip-chip type semiconductor light-emitting element, and more particularly, a full-color composite semiconductor light-emitting element in which a semiconductor light-emitting element and an electrostatic protection element are combined to improve electrostatic withstand voltage and the same. The present invention relates to a light emitting device.
[0002]
[Prior art]
Light emitting devices using semiconductor light emitting elements such as LED lamps and chip LEDs are widely used as LED displays in which a large number of these LED lamps and chip LEDs are arranged on a panel, for example. Semiconductor light-emitting devices (LEDs) emit red, green, and other light depending on the type of compound semiconductor, and are recently formed by stacking a GaN-based compound semiconductor on an insulating and transparent sapphire substrate. Blue and green semiconductor light emitting devices have also been put into practical use.
[0003]
In the case of an LED display, one pixel is constituted by one semiconductor light emitting element in the case of a single color display, but in the case of a full color display, a light emitting element having a set of red, green, and blue which are the three primary colors of light is used. Configured as one pixel.
[0004]
FIG. 9 is a schematic plan view showing the main part of a full-color light emitting device using red, green, and blue semiconductor light emitting elements (LEDs), and FIGS. 10 and 11 are schematic vertical sectional views of the main part.
[0005]
In FIG. 9, a red semiconductor light emitting element 16 is mounted on the right side of a wiring pattern 15a formed on a base substrate (14 in FIG. 10), and a semiconductor light emitting element made of, for example, GaAlAs is used. Is. As shown in FIG. 10, the red semiconductor light emitting element 16 has an n electrode 16a formed on the bottom surface and a p electrode 16b formed on the top surface, and the n electrode 16a is conductively fixed to the wiring pattern 15a with a conductive paste 16c. Furthermore, the p-electrode 16b and the wiring pattern (15b in FIG. 9) are bonded and made conductive by the wire 16d.
[0006]
Each of the green semiconductor light-emitting element 17 and the blue semiconductor light-emitting element 18 is formed by stacking a GaN-based compound semiconductor on an insulating sapphire substrate 17a, and using an InGaN active layer formed as one of the layers as a light-emitting layer. The sapphire substrate side is fixed to the wiring pattern 15a.
[0007]
For example, as shown in FIGS. 9 and 11, the green semiconductor light emitting element 17 has a sapphire substrate 17a bonded to the upper surface of the wiring pattern 15a via a paste 17d, and the upper surface of the semiconductor light emitting element has a p side. The electrode 17c and the n-side electrode 17b are formed, and the p-side electrode 17c is bonded by the wiring pattern 15b and the wire 17e, and the n-side electrode 17b is bonded by the wiring pattern 15d and the wire 17f.
[0008]
The same applies to the blue semiconductor light-emitting element 18 and is indicated by parenthesized symbols in FIG.
[0009]
In general production of such a full-color light emitting device in which one set of red, green and blue is one pixel, red, green and blue semiconductor light emitting elements are separately die-bonded on a wiring pattern, and these semiconductors are manufactured. In general, the process of wire bonding is used to electrically connect each of the light emitting elements independently, and the green and blue colors of the GaN-based semiconductor light emitting elements are used when manufacturing a high brightness full color light emitting device. When green is mounted, green and blue semiconductor light emitting elements are semiconductor light emitting elements having two electrodes on a sapphire substrate, so two wires are required for each of green and blue. Therefore, a full-color light emitting device using red, green, and blue semiconductor light emitting elements requires at least five wire junctions.
[0010]
In addition, GaN-based compound semiconductors have the disadvantage of low electrostatic withstand voltage, which may cause characteristic destruction during mounting.
[0011]
With respect to electrostatic breakdown of such green and blue semiconductor light emitting devices, as described in Japanese Patent Laid-Open No. 9-148625, the electrostatic withstand voltage of semiconductor light emitting devices using GaN compound semiconductors is improved. Therefore, it can be an effective means to provide a compensation diode for reverse withstand voltage compensation.
[0012]
The compensation diode for reverse withstand voltage compensation in the semiconductor light emitting device described in this publication includes an n-conducting first layer electrically connected to the p-side electrode of the semiconductor light-emitting device and an n-side electrode of the semiconductor light-emitting device. The p-conductivity type second layer connected to each other forms a pn junction. With such a configuration, destruction due to static electricity applied in the reverse direction to the light emitting portion is prevented.
[0013]
[Problems to be solved by the invention]
In the case where the brightness as a full color is insufficient in the conventional manufacturing method, the lack of brightness is compensated by increasing the number of semiconductor light emitting elements. However, when blue and green are increased, the number of wires is increased as described above. Since two wires increase per wire, the wires become complicated during wire bonding. When the number of wires increases, it is effective to separate the mounting position of the semiconductor light emitting element to avoid contact between the wires, but it is necessary to enlarge the wiring pattern for mounting the semiconductor light emitting element and further to separate the wiring pattern to be bonded Therefore, there is a problem that the apparatus itself cannot be reduced in size. Furthermore, in the wiring where the loop straddles the upper surface of the semiconductor light emitting element, the light on the light emission observation surface side is blocked, which causes a reduction in luminance.
[0014]
In addition, when the apparatus described in Japanese Patent Application No. 9-18882 is used, even if the number of wires can be reduced, the compensation diode is necessarily larger than the semiconductor light emitting element, so that there is a limit to making the semiconductor light emitting elements close to each other. There is a problem that color mixing cannot be sufficiently achieved when light is emitted simultaneously.
[0015]
Further, in recent years, as shown in FIG. 12, a parabolic reflecting cup material 22 molded of PC, ABS resin or the like is attached to the outer peripheral portions of the red, green, and blue semiconductor light emitting elements 19, 20, and 21 to obtain high brightness. Light-emitting devices aiming to be made are being manufactured. However, since the parabolic reflective cup material 22 is disposed on the outer periphery of the red, green, and blue semiconductor light emitting elements 19, 20, and 21, light emitted from each semiconductor light emitting element is shielded by adjacent elements. Because of the difference in band gap energy, the light emitted from the blue semiconductor light emitting element 21 is absorbed by the light emitted from the red semiconductor light emitting element 19, and the distance to the cup slope is not uniform with respect to the side surface of the semiconductor light emitting element. There was a problem that it did not work efficiently.
[0016]
SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor light emitting element capable of full color light emission that can be easily electrically connected and can improve the withstand voltage against application of a high voltage such as static electricity or surge, and a light emitting device using the same. .
[0017]
[Means for Solving the Problems]
The present invention is a full-color composite comprising a combination of an electrostatic protection Si diode conductively connected to a lead frame or a substrate and red, green and blue semiconductor light emitting elements conductively mounted on the Si diode. A semiconductor light emitting device, wherein the green and blue semiconductor light emitting devices are flip chip type semiconductor light emitting devices containing GaN, and micro bumps are formed on the n side and p side electrodes, and the n side and The p-side micro-bump is made conductive with the polarity opposite to that of the Si diode.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
The invention of claim 1 is an electrostatic protection Si diode that is conductively connected to a lead frame or a substrate; Above A full-color composite semiconductor light-emitting device composed of a combination of red, green and blue semiconductor light-emitting devices conductively mounted on a Si diode Light emitting device equipped with Because The red semiconductor light emitting element is made of GaAlAs or InGaAlP, The green and blue semiconductor light emitting devices But GaN Made of compound semiconductor Flip chip type semiconductor light emitting device Of the flip-chip type semiconductor light emitting device n-side and p-side electrodes And p electrode and n electrode formed on the surface of the Si diode Micro bump The green and blue semiconductor light-emitting elements are arranged on the lead frame or the wiring pattern drawing side of the substrate rather than the red semiconductor light-emitting elements. By mounting a red, green, and blue semiconductor light emitting element on a Si diode for electrostatic protection and conducting connection, the electrostatic withstand voltage of a GaN-based semiconductor light emitting element with a particularly low electrostatic withstand voltage is greatly increased. Improved, Si diodes are shared, and GaN-based semiconductor light-emitting elements are connected by micro bumps, reducing the number of wire bonding and reducing the size of the device by bringing red, green, and blue semiconductor light-emitting elements closer to each other. It is possible to improve the color mixing property of the color. In addition, since the number of wires can be reduced to the minimum by microbump bonding, the light on the light emission observation surface side blocked by the wires can be effectively extracted, and high brightness can be realized.
[0019]
Also, The green and blue semiconductor light emitting elements are arranged corresponding to the lead frame or the wiring pattern drawing side of the substrate. thing Thus, the color mixing property is improved, and the heat dissipation of the GaN semiconductor light emitting device that generates a large amount of heat can be improved.
[0021]
Claim 2 According to the invention, a recess is formed on the surface of the Si diode to drop and mount the red semiconductor light emitting element. red When the semiconductor light emitting device is mounted in the recess, red The semiconductor light emitting element has a height relationship embedded in the upper end surface of the Si diode. Claim 1 of Light emitting device Since the red semiconductor light-emitting element is mounted so as to be buried in the Si diode, interference with the green and blue semiconductor light-emitting elements can be eliminated, and an inclined surface extending from the top surface of the Si diode to the bottom surface of the recess can be illuminated. Since it can be used as a reflecting surface, it is possible to efficiently extract light to the light emission observation surface side.
[0022]
Claim 3 According to the invention, at least three of the concave portions are provided on the surface of the Si diode, and at least one semiconductor light emitting element of each color of red, green, and blue is mounted on each of the concave portions. Light emitting device Since the red, green, and blue semiconductor light emitting devices are individually dropped into the recesses, the interference of the red, green, and blue semiconductor light emitting devices is eliminated, and all the red, green, and blue semiconductor light emitting devices are used. On the other hand, since the inclined surface extending from the upper surface of the Si diode to the bottom surface of the recess can be used as a light reflecting surface, light can be efficiently extracted to the light emission observation surface side for all the semiconductor light emitting elements.
[0023]
Claim 4 The invention of claim 1 further comprises a common electrode on the surface of the Si diode that conducts as a p-side or an n-side with respect to all of the semiconductor light emitting elements of red, green, and blue. 3 In any of Light emitting device The electrode on the upper surface of the Si diode can be shared and used as an anode common or a cathode common.
[0026]
Hereinafter, specific examples of embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic plan view showing a main part of a full-color composite semiconductor light emitting device according to an embodiment of the present invention, and FIGS. 2 and 3 are schematic vertical sectional views of the main part.
[0027]
In FIG. 1, wiring patterns 2a, 2b, 2c, and 2d are uniformly formed on the surface of the base substrate 1 fixed to the mounting surface of the display panel. Of these patterns, the wiring pattern 2a having a large planar shape is formed. The upper surface is a mounting surface for the full-color composite semiconductor light emitting element A. In the illustrated example, one composite semiconductor light emitting element A is mounted. However, if the wiring patterns 2a and 2b, 2c, and 2d are changed, for example, the composite semiconductor light emitting element A is fixed in the longitudinal direction. It is also possible to have assemblies arranged at intervals.
[0028]
The composite semiconductor light emitting element A is electrically connected to an upper surface of the Si diode 3 and an electrostatic protection Si diode 3 conductively fixed on the wiring pattern 2a by a conductive paste (for example, a resin containing Ag as a filler) 4. It is composed of three semiconductor light emitting elements 5, 6 and 7 of red, green and blue.
[0029]
As shown in FIGS. 2 and 3, the Si diode 3 has an n-type silicon substrate 3 a as a base material, an n-pole 3 b is formed on the bottom surface thereof, and is electrically connected to the wiring pattern 2 a through the conductive paste 4. An oxide film 3c is formed on the upper surface except for a part (see FIG. 2). The p-type semiconductor regions 3d and 3e divided into two regions are diffused into the n-type silicon substrate 3a by implanting p-type impurity ions using the two portions not covered with the oxide film 3c as diffusion windows. Form (see FIG. 3). The diffusion region of these p-type semiconductor regions 3d and 3e is uniquely determined in size and depth by the amount of implanted p-type impurity ions. In the present invention, the distance between the p-type semiconductor regions 3d and 3e is determined. Is 10 μm or more.
[0030]
On the surface of the n-type silicon substrate 3a, as shown in FIG. 1, an n-electrode 8a, a first p-electrode 8b, and a second p-electrode 8c are formed by metal vapor deposition. The n electrode 8a is formed widely except for the left end side of the surface of the Si diode 3, and as shown in FIGS. 2 and 3, the oxide film 3c is not formed and the n-type silicon substrate 3a is exposed. It is joined. On the other hand, the first p-electrode 8b and the second p-electrode 8c are arranged along the left end portion, and are respectively formed in the p-type semiconductor regions 3d and 3e (portions shown by broken lines in FIG. 1) diffused in the n-type silicon substrate 3a. It is connected.
[0031]
The red semiconductor light-emitting element 5 is mounted on the right side of the n-electrode 8a and uses a conventionally known semiconductor light-emitting element made of GaAlAs or InGaAlP. As shown in FIG. 2, the red semiconductor light-emitting element 5 has a p-electrode 5a formed on the bottom surface and an n-electrode 5b formed on the top surface. The p-electrode 5a is formed on the n-electrode of the Si diode 3 with a conductive paste 5c. The n electrode 5b is bonded and connected to the wiring pattern 2b by the wire 9a.
[0032]
Each of the green semiconductor light-emitting element 6 and the blue semiconductor light-emitting element 7 has an InGaN active layer formed as a single layer in which a GaN-based compound semiconductor is stacked on a transparent sapphire substrate (6a, 7a). The light emitting layer is mounted on the upper surface of the flip chip type Si diode 3.
[0033]
That is, as shown in FIG. 3, for example, the green semiconductor light emitting element 6 is formed by depositing an n-side electrode 6b and a p-side electrode 6c on the respective surfaces of an n-type layer and a p-type layer laminated on a transparent sapphire substrate 6a. Formed. Micro bumps 6d and 6e are formed on the surfaces of the n-side electrode 6b and the p-side electrode 6c, respectively. As shown in FIG. 1, the green semiconductor light emitting element 6 is mounted so as to straddle the n electrode 8a and the first p electrode 8b, and the n side electrode 6b and the p side electrode 6c are respectively connected to the first p electrode 8b and n. Mounted to the electrode 8a.
[0034]
The same applies to the blue semiconductor light emitting element 7, and the n-side electrode (7 b) is mounted on the second p electrode 8 c and the p-side electrode (7 c) by being mounted so as to straddle the n electrode 8 a and the second p electrode 8 c. Is a mount joined to the n-electrode 8a. In FIG. 3, in order to show the junction between the blue semiconductor light-emitting element 7 and the second p-electrode 8c together, the relationship between the blue semiconductor light-emitting element 7 and the second p-electrode 8c is represented by the reference numerals in parentheses. For example, the code | symbol 7a is a sapphire substrate, and the code | symbol 7c shows the p side electrode.
[0035]
Here, the planar shape of the Si diode 3 is substantially a regular square as shown in FIG. 1, and each of the red, green, and blue semiconductor light emitting elements 5, 6, and 7 is a single circle drawn around the center of the Si diode 3. It will be arranged along. That is, the center portion of each of the semiconductor light emitting elements 5, 6 and 7 is located on a circle having the center of the Si diode 3 as the origin, and the center angle between the centers is substantially the same. A positional relationship that is 120 ° is provided. As a result, the semiconductor light-emitting elements 5, 6, and 7 can have substantially the same adjacent distance in the direction along the array circle, thereby improving the color mixing of red, green, and blue colored light emission. it can. Also, with such an arrangement, the green semiconductor light emitting element 6 and the blue semiconductor light emitting element 7 are located in a portion close to the outline of the Si diode 3, so that these green and blue using GaN-based compound semiconductors that generate a large amount of heat. Even in the semiconductor light emitting elements 6 and 7, since heat dissipation is promoted, the reliability of the light emitting device can be improved.
[0036]
Along with the mounting of the green and blue semiconductor light emitting elements 6 and 7, the first and second p electrodes 8b and 8c are bonded to the wiring patterns 2c and 2d by the wires 9b and 9c, respectively, so that one composite semiconductor light emission is achieved. Element A is assembled in a conducting state.
[0037]
FIG. 4 is an equivalent circuit diagram constituted by the above assembly. The green and blue semiconductor light emitting elements 6 and 7 have a p-side electrode and an n-side electrode with respect to the p-electrode and n-electrode of the Si diode 3, respectively. Connected in the opposite direction. Accordingly, in the forward direction of the green and blue semiconductor light emitting elements 6 and 7, the resistance component R of the n-type silicon substrate 3a of the Si diode 3 serves as a protective resistance, and the applied voltage due to static electricity is a Zener of the Si diode 3. When the breakdown voltage is higher than the breakdown voltage, the overcurrent is released by the reverse bypass (Zener breakdown phenomenon) of the Si diode 3. In addition, overcurrent is released by the forward conduction of the Si diode 3 in the reverse direction of the green and blue semiconductor light emitting elements 6 and 7. Therefore, it is possible to prevent overcurrent from flowing into the green and blue semiconductor light emitting elements 6 and 7, thereby preventing the green and blue semiconductor light emitting elements 6 and 7 from electrostatic breakdown.
[0038]
In the above configuration, when the red, green, and blue semiconductor light emitting elements 5, 6, and 7 are energized, light from the respective light emitting layers is emitted. In the red semiconductor light emitting element 5, the n-electrode 5b side is the first main light emitting surface. Further, in the green and blue semiconductor light emitting elements 6 and 7, there is a component of light that passes through downward and laterally, but since the sapphire substrate 6a is transparent, the surface facing upward in FIG. 3 is the main light extraction surface. Is obtained. Therefore, a pixel unit capable of full color light emission is formed in one composite semiconductor light emitting device A by the respective light emission colors of the three primary colors of semiconductor light emitting devices 5, 6 and 7 of red, green and blue light, and combinations thereof. Will be.
[0039]
In the present invention, even when the red, green and blue semiconductor light emitting elements 5, 6 and 7 required for full color light emission are mounted on one common Si diode 3 as a unit, they are formed by micro bumps or the like. Bonding can reduce the size of the light emitting device, reduce the number of wires, improve light blocking caused by the wires straddling the upper surface of the light emitting surface, and facilitate assembly.
[0040]
In addition, by providing the Si diode 3, electrostatic breakdown of each of the semiconductor light emitting elements 5, 6, and 7 can be prevented, and in particular, green and blue semiconductor light emitting elements 6, which require a GaN-based semiconductor compound having a low electrostatic withstand voltage, are essential. 7 is also improved, so that it is possible to perform light-emitting display that effectively uses full-color compatible pixels of a combination of red, green, and blue semiconductor light-emitting elements 5, 6, and 7.
[0041]
FIG. 5 is a schematic perspective view showing an example of a composite semiconductor light emitting device in which a reflection band is provided on the upper surface of the Si diode, and FIG.
[0042]
In this example, a reflection band 11 is formed on the upper surface of the Si diode 3 of the composite semiconductor light emitting device A shown in FIGS. 1 to 3. Description is omitted.
[0043]
The reflection band 11 is made of a metal such as Al having a substantially trapezoidal longitudinal section as shown in FIG. 6, and the angle between the three branches 11a, 11b, and 11c of the same length is mutually different. It has a planar shape developed with a relationship of 120 °. The reflection band 11 positions the base point 11d where these branches 11a, 11b and 11c intersect with the center of the Si diode 3, and the two branches 11a and 11b are on the n-electrode 8a and the remaining branches. 11c is installed in such a posture that it passes between the first p electrode 8b and the second p electrode 8c. The branches 11 a to 11 c are bonded and fixed to the respective joint surfaces with an insulating adhesive 12.
[0044]
Here, the branches 11a to 11c of the reflection band 11 have dimensions higher than the upper ends of the red, green, and blue semiconductor light emitting elements 5, 6, and 7 as shown in FIG. A reflective surface that tapers in the light emitting direction faces each semiconductor light emitting element 5, 6, 7. Accordingly, the respective semiconductor light emitting elements 5, 6, and 7 are individually divided by the respective branches 11a, 11b, and 11c, and light absorption due to the difference in band gap energy of the materials constituting the respective semiconductor light emitting elements 5, 6, and 7 is achieved. The light emission of each color can be obtained as a high output. That is, the semiconductor light emitting elements 5, 6, and 7 are surrounded by the branches 11a to 11c and can be arranged independently so that each one does not interfere optically, so that light absorption between them can be suppressed. High output light emission is obtained and the color is also sharpened.
[0045]
In addition, since the reflecting surfaces of the branches 11a to 11c of the reflection band 11 are inclined, the green and blue semiconductor light emitting elements 6 and 7 including the transparent sapphire substrates 6a and 7a are particularly compared with the red semiconductor light emitting element 5. Since a lot of light components that escape to the side are included, the light can be reflected and collected in the light emitting direction, and the light emission luminance is also improved.
[0046]
In the examples of FIGS. 5 and 6, the metal is fixed as a reflective band by an insulating adhesive, but a light-reflective synthetic resin layer may be formed as it is as a reflective band. Good. In the example shown in the figure, the reflection band has a branch shape, but it is needless to say that the same effect can be obtained even if the reflection ring has a continuous ring shape.
[0047]
Therefore, conventionally, the reflected light is collected by forming a parabolic reflecting surface on the mount portion of the lead frame on which the semiconductor light emitting element is mounted. However, it is not necessary to provide such a parabola.
[0048]
FIG. 7 is a schematic perspective view showing an example of a composite semiconductor light emitting device in which a concave portion is provided on the upper surface of the Si diode and the semiconductor light emitting device is arranged therein, and FIG. 8 is a schematic vertical sectional view of the main part.
[0049]
In this example, recesses 13a, 13b, and 13c are formed at three locations on the upper surface of the Si diode 3 of the composite semiconductor light emitting device A shown in FIGS. 1 to 3, and the same members as those in the previous example are denoted by common reference numerals. The detailed explanation is omitted.
[0050]
The recesses 13a to 13c have a circular planar shape, and their centers are arranged on the same circle around the center of the Si diode 3, and are arranged at a pitch of 120 ° in the center angle. That is, by arranging the red, green, and blue semiconductor light emitting elements 5, 6, and 7 in alignment with the recesses 13a to 13c, as described with reference to FIG. The semiconductor light emitting elements 5, 6, and 7 are arranged on the same circle at the same angular pitch. And as shown in FIG. 8, each recessed part 13a, 13b is formed in the mortar shape which the opening cross section taper toward the bottom side.
[0051]
As shown in FIG. 8A, the n-electrode 8a is formed from the upper surface of the Si diode 3 to the inclined surface and the bottom surface of the recess 13a, and is joined to the n-type silicon substrate 3a. Also, as shown in FIG. 8B, similarly in the recess 13b, the one end side of the n electrode 8a and the first p electrode 8b are formed from the upper surface of the Si diode 3 to the inclined surface and the bottom of the recess 13b. The first p electrode 8b is joined to the p-type semiconductor region 3d at the bottom of the recess 13b. The green semiconductor light emitting element 6 has its p-side microbump 6e bonded to the n-electrode 8a, the n-side microbump 6d bonded to the first p-electrode 8b, and the wire 9b bonded to the first p-electrode 8b. ing.
[0052]
The mounting structure of the blue semiconductor light emitting element 7 in the recess 13c is the same. In FIG. 8B, the reference numerals are indicated in parentheses.
[0053]
As described above, by incorporating the red, green, and blue semiconductor light emitting elements 5, 6, and 7 so as to be dropped into the recesses 13a, 13b, and 13c, respectively, the optics between the semiconductor light emitting elements 5, 6, and 7 can be obtained. Is not subject to general interference. For this reason, the light absorption by the difference in the band gap energy of the material used for each semiconductor light emitting element 5, 6, and 7 is suppressed, and each luminescent color becomes clearer and high light emission output is obtained.
[0054]
Further, if the n electrode 8a and the first and second p electrodes 8b and 8c are each made of a metal material having a high light reflectivity, the inclined surfaces on the inner periphery of the recesses 13a to 13c can be used as the light reflecting surfaces. it can. Therefore, the light leaking sideways or downward from the red, green, and blue semiconductor light emitting elements 5, 6, and 7 can be collected in the light emitting direction from the light reflecting surface, and the light emission luminance of each color can be increased. Therefore, as in the case of providing the reflection band 11 of FIG. 5, it is not necessary to form a parabolic reflection surface on the lead frame or the mount portion of the substrate, and the structure can be simplified.
[0055]
Furthermore, since the red, green, and blue semiconductor light emitting elements 5, 6, and 7 are incorporated so as not to protrude from the surface of the Si diode 3, the composite semiconductor light emitting element A is compared with that shown in FIGS. The height dimension can be reduced, and the finally manufactured light-emitting device can be made thinner.
[0056]
The composite semiconductor light emitting elements A shown in FIGS. 1 to 8 are all assembled as a predetermined number arrayed on the pedestal substrate 1, and a plurality of pedestal substrates 1 are mounted on the display panel and the wiring substrates 2a to 2a are mounted. By connecting a conduction circuit to 2c, it can be provided as a product of an image display device. Since the green and blue semiconductor light emitting elements 6 and 7 that use a GaN-based compound semiconductor that is relatively weak against static electricity are protected by the Si diode 3, a display device with a high electrostatic withstand voltage can be provided. Further, even if the composite semiconductor light emitting element A shown in FIGS. 1 to 9 is used as a full color light source, a high output light emitting device can be realized.
[0057]
【The invention's effect】
According to the first aspect of the present invention, the electrostatic withstand voltage of the GaN-based semiconductor light-emitting element having a particularly low electrostatic withstand voltage is greatly improved, the Si diode is shared, and the GaN-based semiconductor light-emitting elements are connected by micro bumps. In addition to reducing the number of times, the red, green, and blue semiconductor light emitting elements can be brought closer to each other, improving the color mixing property and reducing the size of the semiconductor light emitting device. There is an extraordinary effect that light can be extracted effectively and high brightness can be realized.
[0058]
Also, The color mixing characteristics of the red, green, and blue semiconductor light emitting elements are improved, and the GaN semiconductor light emitting elements are mounted on the lead frame or on the drawing side of the mounting surface of the substrate. Can improve the reliability.
[0060]
Claim 2 In this invention, mutual interference between the red, green, and blue semiconductor light emitting elements can be eliminated, and the inclined surface of the recess can be used as a reflecting surface, so that the light extraction efficiency is improved and a conventional lead frame, etc. Thus, the parabola formed in the above is no longer necessary, and high performance and low cost are possible.
[0061]
Claim 3 In this invention, it is possible to emit light that is not subjected to light absorption due to the difference in the materials of the semiconductor light emitting elements, and the light emitting efficiency of each color is improved because the semiconductor light emitting elements are mounted in the recesses for each color. Clear light emission can be obtained.
[0062]
Claim 4 In this invention, since one of the wiring patterns on the upper surface of the Si diode is shared, it can be the anode common or the cathode common.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing a main part of a full-color composite semiconductor light emitting device according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a main part showing a mounting structure of a red semiconductor light emitting element
FIG. 3 is a schematic diagram of a main part showing a mounting structure of a green semiconductor light emitting device and a blue semiconductor light emitting device.
FIG. 4 is a circuit diagram for explaining an electrostatic protection function by an electrostatic protection element.
FIG. 5 is a schematic perspective view showing an example in which a reflection band is formed on a Si diode.
6 is a schematic longitudinal sectional view showing the main part of the element in the example of FIG.
FIG. 7 is a schematic perspective view showing an example in which recesses are provided at three locations on the surface of a Si diode and a semiconductor light emitting device is incorporated in these recesses.
8 is a schematic cross-sectional view of the main part in the example of FIG. 7,
(A) is a figure which shows the mounting structure of a red semiconductor light-emitting device
(B) is a figure which shows the mounting structure of the green and blue semiconductor light-emitting device.
FIG. 9 is a schematic plan view showing a main part of a conventional full-color light emitting device.
FIG. 10 is a schematic diagram of a main part showing a conventional structure in which a red semiconductor light emitting element is mounted.
FIG. 11 is a schematic diagram of a main part showing a conventional structure in which a green semiconductor light emitting element and a blue semiconductor light emitting element are mounted.
FIG. 12 is a schematic perspective view of a conventional full-color light emitting device equipped with a reflective cup material.
[Explanation of symbols]
A composite semiconductor light emitting device
1 Base board
2a, 2b, 2c, 2d Wiring pattern
3 Si diode
3a Silicon substrate
3b n pole
3c oxide film
3d, 3e p-type semiconductor region
4 Conductive paste
5 Red semiconductor light emitting device
5a p electrode
5b n electrode
5c conductive paste
6 Green semiconductor light emitting device
7 Blue semiconductor light emitting device
6a, 7a Sapphire substrate
6b, 7b n-side electrode
6c, 7c p-side electrode
6d, 7d micro bump
8a n electrode
8b 1p electrode
8c Second p electrode
9a, 9b, 9c wire
11 Reflection band
11a, 11b, 11c branches
11d base point
12 Adhesive
13a, 13b, 13c recess

Claims (4)

And Si diode for electrostatic protection which is conductively connected to the lead frame or substrate, red is conducted mounted on the Si diode, green, composite semiconductor light-emitting device of a full color comprising a combination of the respective colors of the semiconductor light-emitting element of blue A light emitting device mounted thereon, wherein the red semiconductor light emitting element is made of GaAlAs or InGaAlP, and the green and blue semiconductor light emitting elements are made of a flip chip type semiconductor light emitting element made of a GaN compound semiconductor, and the flip chip type The n-side and p-side electrodes of the semiconductor light-emitting element and the p-electrode and the n-electrode formed on the surface of the Si diode are bonded with micro-bumps with opposite polarities, and the green and blue semiconductor light-emitting elements are connected to the red semiconductor Arranged on the lead frame or substrate wiring pattern lead-out side of the light emitting element Consisting of Te light-emitting device. A recess for dropping and mounting the red semiconductor light emitting element is formed on the surface of the Si diode, and the red semiconductor light emitting element is embedded in the upper end surface of the Si diode when the red semiconductor light emitting element is mounted in the recess. It is formed by a related claim 1 emitting device according. Wherein the surface of the Si diode, provided the recesses in at least three locations, at least the red each of these recesses, green light emitting device mounted composed claim 2 wherein each one of the semiconductor light emitting element of blue. On the surface of the Si diode, the red, green, light emitting device according to any one of claims 1 to 3 comprising a common electrode for conducting a p-side or n-side for all the semiconductor light-emitting element of blue .

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