JP2008124267A - Light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device which improves the reliability with light-emitting element configuration suited for glass encapsulation. <P>SOLUTION: The light-emitting device comprises an LED element 2 having an electrode formation section 2a where electrodes 25 and 27 are formed, an element mounting substrate 3 for mounting the LED element 2, and a glass encapsulation section 4 which encapsulates the LED element 2 formed on the element mounting substrate 3 and has a glass transition point of 340°C or higher. No passivation film is provided on the electrode formation section 2a of the LED element 2 to bring the electrode 27 into direct contact with a hollow section 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting device in which a light emitting element is sealed with a glass material.

  2. Description of the Related Art Conventionally, a light emitting device in which a light emitting element such as a light emitting diode (LED) is sealed with a translucent resin material such as epoxy or silicone is known. As an LED element, a buffer layer, an n-type layer, a light emitting layer, and a p-type layer are stacked on a growth substrate such as sapphire, an n-type layer is partially exposed by an etching process, and an n-electrode is provided. It is common to provide a p-electrode.

  FIG. 7 is a bottom view of an LED element showing a conventional example. As shown in FIG. 7, the LED element 102 is formed with the p-side contact electrode 125 and the n-electrode 127 as described above, and the electrode forming portion is entirely covered with the passivation film 140. The passivation film 140 ensures the moisture resistance of the element during resin sealing.

  In this type of light emitting device, there is a problem that the translucent resin is deteriorated by light, heat, etc. emitted from the light emitting element. In particular, when a group III nitride compound semiconductor that emits short-wavelength light is used as a light-emitting element, the translucent resin near the element is yellow due to the high-energy light emitted from the light-emitting element and the heat generated by the element itself. The light extraction efficiency may decrease with time.

In order to prevent such deterioration of the sealing member, a light emitting device using glass as the sealing member has been proposed (see, for example, Patent Document 1). The light emitting device described in Patent Document 1 realizes glass sealing by bonding a plate-like glass material to a ceramic substrate on which an LED chip is mounted by hot pressing.
International Publication No. 2004/082036 Pamphlet

  By the way, in the light-emitting device described in Patent Document 1, the light-emitting element is heated at a higher temperature than the resin-sealed one at the time of glass sealing, and the light-emitting element is sealed by glass having better moisture resistance than the resin. ing. Thus, in the case of glass sealing, the performance required for the light emitting element is different from that in the case of resin sealing. Therefore, the inventors of the present application have made extensive studies on the configuration of a light-emitting element suitable for glass sealing in order to improve the reliability of the device.

  Accordingly, an object of the present invention is to provide a light-emitting device in which the structure of the light-emitting element is suitable for glass sealing and the reliability of the device can be improved.

In order to achieve the above object, the present invention
A light emitting element having an electrode forming portion provided with an electrode;
A mounting portion on which the light emitting element is mounted;
A glass sealing part formed on the mounting part, sealing the light emitting element and having a glass transition point of 340 ° C. or higher,
A light-emitting device is provided in which a passivation film is not formed on the electrode forming portion of the light-emitting element.

In order to achieve the above object, the present invention
A light emitting element having an electrode forming portion provided with an electrode;
A mounting portion on which the light emitting element is mounted;
A glass sealing portion formed on the mounting portion, sealing the light emitting element, having a glass transition point of 340 ° C. or higher;
There is provided a light emitting device comprising: a hollow portion formed between the mounting portion and the light emitting element and in direct contact with the electrode of the light emitting element.

In order to achieve the above object, the present invention
A light emitting element having an electrode forming portion provided with a pair of electrodes;
A mounting portion on which the light emitting element is mounted;
A glass sealing part formed on the mounting part, sealing the light emitting element and having a glass transition point of 340 ° C. or higher,
The light emitting device is provided, wherein the electrode forming portion includes a passivation film forming region in which a passivation film is formed and interposed between the electrodes, and a passivation film non-forming region in which a passivation film is not formed. The

In the above light emitting device,
The electrode of the light emitting element preferably includes a conductive oxide.

In the above light emitting device,
The electrode of the light emitting element preferably includes ITO (Indium Tin Oxide).

In the above light emitting device,
The light emitting element is preferably a flip-chip mounted GaN-based LED element.

  According to the present invention, the configuration of the light-emitting element is suitable for glass sealing, and the reliability of the device can be improved.

  FIG. 1 is a schematic longitudinal sectional view of a light emitting device showing an embodiment of the present invention. In FIG. 1, each part is shown in a size different from the actual size in order to clarify the configuration of each part.

  As shown in FIG. 1, the light emitting device 1 includes an LED element 2 as a flip chip type light emitting element, and the LED element 2 and power supplied from the outside is supplied to the LED element 2 through a conductive portion. An element mounting substrate 3 as a mounting portion to be mounted and a glass sealing portion 4 formed on the element mounting substrate 3 for sealing the LED element 2 are provided. A hollow portion 5 is formed between the LED element 2 and the element mounting substrate 3.

The LED element 2 is made of a group III nitride compound semiconductor and emits blue light having an emission wavelength of 460 nm. In this embodiment, the LED element 2 is formed in a 346 μm square, and the thermal expansion coefficient is 7 × 10 ⁻⁶ / ° C.

  The LED element 2 is formed by sequentially laminating an AlN buffer layer 21, an n-GaN layer 22, an MQW (multiple-quantum well) layer 23, and a p-GaN layer 24 on a sapphire substrate 20 serving as a growth substrate. Is formed. The MQW layer 23 is formed by laminating six pairs of InGaN layers and AlGaN barrier layers alternately. The number of MQW layer 23 pairs is arbitrary.

  The LED element 2 has a p-side contact electrode 25 formed on the p-GaN layer 24 and made of ITO (Indium Tin Oxide) on the mounting surface, and a part of the p-side contact electrode 25 is made of Ni—Au. A p-side pad electrode 26 is formed. Further, an n electrode 27 is provided on an exposed portion of the n-GaN layer 22 formed by performing an etching process from the p-GaN layer 24 to the n-GaN layer 22. The n-electrode 27 has a contact layer and a pad layer formed in the same area.

The p-side contact electrode 25 is made of ITO (Indium Tin Oxide) having 7 × 10 ⁻⁶ / ° C. which is substantially equal to the thermal expansion coefficient of the LED element 2 and having a refractive index n = 2.0. The contact electrode 25 is preferably formed by sputtering from the viewpoint of adhesion strength, but may be formed by EB vapor deposition or resistance heating vapor deposition. The n-electrode 27 is formed of an Al layer 27a, a thin Ni layer 27b that covers the Al layer 27a, and an Au layer 27c that covers the surface of the Ni layer 27b. Au bumps 28 are formed on the p-side pad electrode 26 and the n-electrode 27, respectively.

  Further, the LED element 2 is not formed with a passivation film that covers the exposed portion of the p-side contact electrode 25 and the n-GaN layer 22 on the element mounting substrate 3 side. As a result, the p-side contact electrode 25 is in direct contact with the glass sealing portion 4 or the hollow portion 5.

The element mounting substrate 3 is a laminated substrate made of a polycrystalline sintered material of Al ₂ O ₃ and has a thermal expansion coefficient of 7 × 10 ⁻⁶ / ° C. which is substantially equal to the thermal expansion coefficient of the LED element 2. The element mounting substrate 3 may be made of another material as long as it has a thermal expansion coefficient equivalent to that of the LED element 2. Specifically, the element mounting board 3 is configured by laminating a first layer 3a on the mounting surface side and a second layer 3b on the opposite side to the mounting surface. The second layer 3b is formed smaller than the first layer 3a in plan view, and a stepped portion 3c of the first layer 3a and the second layer 3b is provided on the outer edge of the element mounting substrate 3. Here, the thickness of the first layer 3a is 0.15 mm, the thickness of the second layer 3b is 0.1 mm, and the thickness of the element mounting substrate 3 is 0.25 mm.

  Further, on the element mounting surface of the element mounting substrate 3, a W layer 36 patterned according to the electrode shape of the LED element 2, a thin Ni layer 30 covering the surface of the W layer 36, and a Ni layer 30 A circuit pattern 32 including a thin-film Au layer 31 covering the surface is formed. And on the surface opposite to the mounting surface of the element mounting substrate 3, a W layer 36 patterned according to the shape of the terminal for external connection, a thin Ni layer 30 covering the surface of the W layer 36, An external wiring pattern 35 made of a thin Au layer 31 covering the surface of the Ni layer 30 is formed. The circuit pattern 32 and the external wiring pattern 35 are electrically connected by a via pattern 34 made of W provided in a via hole 33 penetrating the element mounting substrate 3 in the thickness direction. The external wiring pattern 35 is formed up to the stepped portion 3c described above.

The glass sealing part 4 seals the element mounting substrate 3 on which the LED element 2 is mounted by hot-pressing colorless and transparent ZnO-based glass as an inorganic sealing material. In the present embodiment, the glass sealing part 4 is heat-sealed glass, and has a refractive index of 1.7, a thermal expansion coefficient of about 6 × 10 ⁻⁶ / ° C., and a glass transition that is substantially the same as the element mounting substrate 3. The point (Tg) is 480 ° C. Here, the heat-sealed glass is glass that is molded in a molten state or a softened state by heating, and is different from glass that is molded by a sol-gel method. Since the sol-gel glass has a large volume change at the time of molding, cracks are likely to occur, and it is difficult to form a thick film of glass. However, the heat-fused glass can avoid this problem. Further, since the sol-gel glass generates pores, airtightness may be impaired. However, the heat-sealed glass does not cause this problem, and the LED element 2 can be accurately sealed. Specifically, the glass sealing portion 104 is made of ZnO—B ₂ O ₃ —SiO ₂ —Nb ₂ O ₅ —Na ₂ O—Li ₂ O-based heat-sealing glass and is formed in a rectangular parallelepiped shape. The side surface of the glass sealing portion 4 is formed by cutting a plate glass bonded to the element mounting substrate 3 by hot pressing together with the element mounting substrate 3 with a dicer.

  FIG. 2 is a bottom view showing an electrode forming portion of the LED element. In FIG. 2, the Au bump is omitted.

  As shown in FIG. 2, the p-side pad electrode 26 in the electrode forming portion 2a of the LED element 2 has a circular shape in plan view, and the n-electrode 27 has a square shape in plan view. The p-side pad electrode 26 and the n-electrode 27 are arranged on the LED element 2 so as to face each other. The contact electrode 25 is formed so as to cover the surface of the p-GaN layer 24 as shown in FIG. As described above, the passivation film is not formed on the electrode forming portion 2 a of the LED element 2.

  In the LED element 2 configured in this manner, the p-side pad electrode 26 is electrically connected to the p-side circuit pattern 32 via the Au bump 28 by flip mounting the electrode forming portion 2a toward the substrate side. The n electrode 27 is electrically connected to the n-side circuit pattern 32 via the Au bump 28.

  Hereinafter, a method for manufacturing the light emitting device of the first embodiment will be described. The element mounting substrate 3 is a wafer-like one in which the green sheets of the first layer 3a and the second layer 3b are sintered, and the circuit pattern 32, the via pattern 34, and the external wiring pattern 35 are formed on the sintered body. Is used.

  Then, the plurality of LED elements 2 are positioned with respect to the circuit pattern 32 on the element mounting substrate 3 so that the p-side pad electrode 26 and the n-electrode 27 are arranged at predetermined positions. Next, the LED element 2 is mounted on the element mounting substrate 3 by ultrasonic thermocompression bonding.

Thereafter, a plate-like ZnO—B ₂ O ₃ —SiO ₂ —Nb ₂ O ₅ —Na ₂ O—Li ₂ O-based glass is arranged on each LED element 2 so as to be parallel to the element mounting substrate 3. Then, a pair of molds (not shown) are set on the element mounting substrate 3 side and the glass side, and hot pressing is performed by pressing while heating at 630 ° C., so that the glass is thermocompression bonded to the element mounting substrate 3. The glass sealing part 4 is formed. Here, the hot pressing is performed in a nitrogen atmosphere, and the pressure bonding force is about 100 kg. Moreover, the heating time of the LED element 2 in hot press processing is about 20 minutes to 30 minutes.

  At this time, the glass wraps around between the LED element 2 and the element mounting substrate 3, but since the viscosity of the glass is relatively large, the hollow portion 5 is formed between the p-side pad electrode 26 and the n electrode 27 in the longitudinal section. Remain. Next, the element mounting substrate 3 in which the glass sealing portion 4 is integrated is cut into a predetermined size with a dicer (not shown).

  Here, the characteristics of the light emitting device configured as described above will be described with reference to FIG. FIG. 3 shows a case where an LED element having a passivation film formed on the entire surface of an electrode forming portion and an LED element having no passivation film formed thereon are both heated for a predetermined time and then subjected to a predetermined energization current. It is a graph which shows the change of the forward voltage (Vf) at the time of making light-emit. Specifically, the horizontal axis represents the heating time, and the vertical axis represents the amount of change in Vf relative to Vf before heating.

  Here, as a sample of the LED element used for the experiment, a sample 1 in which a passivation film is not formed, a sample 2 in which a passivation film is formed by an electron beam (EB) vapor deposition method, and a chemical vapor deposition (CVD) method. A plurality of samples 3 each having a passivation film were prepared. The heating temperature of the LED element 2 was 630 ° C., and the heating time was 10 minutes, 20 minutes, and 30 minutes. In FIG. 3, the average values of a plurality of samples 1 to 3 are plotted.

  As shown in FIG. 3, in the sample 2 and the sample 3 on which the passivation film is formed, the change amount (ΔVf) of Vf is larger than that of the sample 1 after heating. Specifically, when heated for 10 minutes, the average value of ΔVf of sample 1 is 0.064V, whereas the average value of ΔVf of sample 2 is 0.278V, and the average value of ΔVf of sample 3 is 0.158V. It has become. When heated for 20 minutes, the average value of ΔVf of sample 1 is 0.082 V, whereas the average value of ΔVf of sample 2 is 0.267 V, and the average value of ΔVf of sample 3 is 0.232 V. ing. When heated for 30 minutes, the average value of ΔVf of sample 1 is 0.088V, whereas the average value of ΔVf of sample 2 is 0.278V, and the average value of ΔVf of sample 3 is 0.243V. It has become. Thus, for LED elements that do not form a passivation film, the change in Vf after heat treatment is small compared to the LED elements that form a passivation film, and excellent reliability such as heat resistance, and It has been found that the amount of light decreases with the change in Vf.

  Next, the relationship between the heating temperature of the LED element and Vf will be described with reference to FIG. FIG. 4 is a graph showing the relationship between the heating temperature of the LED element and the change in forward voltage (Vf) when the LED element is caused to emit light at a predetermined energization current. A plurality of the above-described samples 3 were prepared as samples to be used for the experiment, a heating target temperature was set for each sample, the temperature was raised to the target temperature in 45 minutes, and the target temperature was maintained for 15 minutes. The heating target temperature of the LED element 2 was 200 ° C., 350 ° C., 400 ° C., 450, 500 ° C., and 550 ° C., and Vf after heating in a plurality of samples was measured for each temperature condition. FIG. 4 shows the average value of a plurality of samples under each temperature condition, with the horizontal axis representing the heating temperature and the vertical axis representing the amount of change in Vf relative to Vf before heating.

  As shown in FIG. 4, ΔVf is generated by heating. When the heating temperature is 400 ° C. or higher, the change amount of Vf becomes large, and when the heating temperature is 500 ° C. or more, the change amount of Vf becomes extremely large. Specifically, the average value of ΔVf when heated at 200 ° C. is 0.047 V, the average value of ΔVf when heated at 350 ° C. is 0.047 V, and the average value of ΔVf when heated at 400 ° C. is 0.00. The average value of ΔVf when heated at 223V and 450 ° C is 0.323V, the average value of ΔVf when heated at 500 ° C is 1.413V, and the average value of ΔVf when heated at 550 ° C is 1.547V. there were. As described above, it has been found that the LED element has a large change in Vf at 400 ° C. or more and impairs reliability such as heat resistance.

  It has been experimentally confirmed that sealing processing is possible under conditions of 400 ° C. or higher in a fluorinated glass having a glass transition point of 340 ° C. That is, when the sealing process is performed with glass having a glass transition point of 340 ° C. or higher, the LED element is heated to 400 ° C. or higher. Therefore, when glass having a glass transition point of 340 ° C. or higher is used, a change in Vf of the LED element becomes a problem. Moreover, when performing the sealing process using glass in the temperature range of 400 degreeC or more, it is necessary to heat to the temperature at least about 50 degreeC higher than a glass transition point, and the glass transition point corresponding to this is 350 degreeC. Degree.

  Therefore, according to the light emitting device 1 of the present embodiment, the glass transition temperature of the glass used for the glass sealing portion 4 is 340 ° C. or higher, and the sealing process is performed at a heating temperature of 400 ° C. or higher. Since the passivation film is not formed on 2, it is possible to suppress the increase in Vf of the LED element 2 when the heat treatment at the time of glass sealing is performed, and the reliability of the device can be improved. . Here, since the LED element 2 is sealed by the glass sealing portion 4, the moisture resistance is improved as compared with the conventional resin sealing, and no countermeasures against the corrosion of moisture entering the LED element 2 are required. For this reason, the protection function inside the LED element 2 is not impaired even when the passivation film is not formed. Further, by omitting the passivation film, it is possible to omit the step of forming the passivation film at the time of element manufacture, and to reduce the element manufacturing cost.

  Further, the p-side contact electrode 25 made of ITO has a thermal expansion coefficient substantially equal to that of the main body portion of the LED element 2 and a high adhesion strength. Therefore, even if the boundary of the wrap around the glass exists in the contact electrode 25, The contact electrode 25 does not peel off during the glass sealing process. Moreover, it was confirmed that the p-side contact electrode 25 was not peeled even in the liquid phase thermal shock test 2000 cycles at −40 ° C. ← → 100 ° C. using the sample of the light emitting device 1 of the present embodiment. Further, it has been confirmed that there is no change in the light output and the driving voltage even in the test with the light output of 50 mW, the temperature of 100 ° C., the energization current of 100 mA and 10000 h.

  On the other hand, in the light emitting element using the Au—Co thin film electrode and the Rh—Au electrode as the contact electrodes, the following two states have been confirmed. One is that although the portion where the glass wraps around is good, the electrode bonding is insufficient at the portion where the gas layer is formed, and the light emission luminance at the portion where the gas layer is present is remarkable when the light emitting element is turned on. The state of being lowered or not emitting light is confirmed. The other has confirmed the state which light emission abnormality occurs regardless of the location where electrode peeling occurred and the glass went around and the location where the gas layer was formed.

In addition, the extent of the peeling phenomenon of the p-side contact electrode 25 is determined by the glass-containing Al ₂ O ₃ substrate (thermal expansion coefficient: 12 × 10 ⁻⁶ / ° C.) and phosphate glass (thermal expansion coefficient: 12 × 10 ^−6). / ° C) increases in the aforementioned Au—Co thin film electrode and Rh—Au electrode, but when the ITO p-side contact electrode 25 is used, the adhesion strength with GaN is large and the thermal expansion coefficient is also GaN. Since it is equivalent (7 × 10 ⁻⁶ / ° C.), it has been confirmed that no malfunction occurs. However, in order to obtain stable quality, it is desirable that the coefficient of thermal expansion of the element mounting substrate with respect to the light emitting element is 50 to 150%.

In addition, a plate-like ZnO—B ₂ O ₃ —SiO ₂ —Nb ₂ O ₅ —Na ₂ O—Li ₂ O-based glass is set as the heat fusion glass so as to be parallel to the element mounting substrate 3, and has high viscosity. By hot pressing in the state, processing sufficiently lower than the crystal growth temperature becomes possible, and sealing processability is improved. Further, when the heat-sealing glass moves in parallel to the surface of the element mounting substrate 3 and adheres in a planar shape to form the glass sealing portion 4, the hollow portion 5 is formed between the element mounting substrate 3 and the LED element 2. Therefore, the light reaching the interface between the p-side contact electrode 25 and the hollow portion 5 can be reflected based on the difference in refractive index, and the reflection absorption loss due to the light reaching the element mounting substrate 3. Can be reduced.
In addition, since the ZnO-based glass has a thermal expansion coefficient equivalent to that of the LED element 2, cracks do not occur even if the LED element 2 is enlarged or a plurality of LED elements 2 are mounted. Moreover, ZnO-type glass is excellent in high-temperature moisture resistance than phosphoric acid-type glass, and can make a weather resistance favorable.

  Furthermore, since ITO having a thermal expansion coefficient equivalent to that of the sapphire substrate 20 of the LED element 2 is used as the p-side contact electrode 25, the p-side contact electrode 125 and the GaN-based semiconductor are caused by heat at the time of glass sealing and thermal stress accompanying light emission. Without peeling off the layer, stable light emission characteristics can be imparted over a long period of time, and the reliability is excellent.

Furthermore, the p-side pad electrode 26 and the n-electrode 27 of the LED element 2 are mounted on the circuit pattern 32 by Au bumps 28, and the glass sealing process is performed in a high viscosity state of 10 ⁴ poise or more. It is possible to prevent the glass from entering between the LED element 2 and the circuit pattern 32 and to form the hollow portion 5 stably.

In the embodiment described above, the glass sealing portion 4 is ZnO-based glass and the glass transition point (Tg) is 480 ° C., but is not limited to this. For example, phosphoric acid-based glass transition point. Other materials may be used for the glass sealing portion 4 such as glass having a (Tg) of 400 ° C. or glass having a fluorine-based glass transition point (Tg) of 340 ° C. In short, the Tg of the glass used for the glass sealing part 4 should just be 340 degreeC or more. However, there is a correlation between the glass transition point and the coefficient of thermal expansion. Generally, when the glass transition point is low, the coefficient of thermal expansion increases. Therefore, the element mounting substrate 3 has the same coefficient of thermal expansion as the material of the glass sealing portion 4. It is preferable to select one. Moreover, when using a fluorine-type glass, since the thermal expansion coefficient of glass is 17x10 < ^-6 > / degreeC and the difference of a thermal expansion coefficient with a ceramic is large, for example, the thermal expansion coefficient like copper is comparatively close. You may comprise so that a metal material may contact glass. Further, since the difference in thermal expansion coefficient between the fluorine-based glass and the LED element 2 is large, it is desirable to use an LED element 2 having a 300 μm or less to reduce the influence of the difference in thermal expansion coefficient.

  Moreover, although the glass sealing part 4 demonstrated as what consists of colorless and transparent glass, a colored transparent glass may be sufficient. Furthermore, the glass used for the glass sealing part 4 may be a phosphor-containing glass formed by mixing and melting a sintered phosphor and powdered glass. Furthermore, it is also possible to use a glass in which a phosphor layer is provided by mixing powdered glass and a phosphor, screen-printing on a plate-like transparent glass, and overlaying another transparent glass thereon and heat-treating. good. For example, by using Ce: YAG as the phosphor, the light emitting device 1 that emits white light based on a complementary color of blue light and yellow light can be obtained. Moreover, it is good also as the wavelength conversion type light-emitting device 1 using the other fluorescent substance which can be excited by the blue light radiated | emitted from the LED element 2. FIG.

The material of the p-side contact electrode 25 is not limited to ITO, and In ₂ O ₃ —SnO ₂ (90-10 wt%), AZO [ZnO: Al] —IZO [In ₂ O ₃ —ZnO] (90-10 wt. %), A conductive oxide such as InGaN may be used. In these cases, like ITO, the adhesion strength to GaN is large, and the coefficient of thermal expansion is equivalent to that of GaN.

  Moreover, in the said embodiment, although the passivation film was not formed at all in the electrode formation part 2a of the LED element 2, the area | region between the p side contact electrode 25 and the n electrode 27 in the electrode formation part 2a was shown. Alternatively, the passivation film may be formed, and the passivation film may not be formed in other regions.

For example, as shown in FIG. 5, a passivation film forming region 2 b in which the passivation film 40 is formed by interposing the electrode forming portion 2 a between the electrodes 25 and 27, and a passivation film non-forming region 2 c in which the passivation film 40 is not formed. You may make it have. As shown in FIG. 6, the LED element 2 has the same electrode structure as that described in the above embodiment, and a passivation film 40 is formed from the n-GaN layer 22 to the p-side contact electrode 25 and the n electrode 27. Has been. Here, the passivation film 40 is made of, for example, transparent SiO ₂ and has a refractive index of 1.4. Here, the SiO ₂ layer of the passivation film 40 is not limited to a transparent film, but may be a white scattering reflection film in a polycrystallized state. Further, the passivation film 40 is not limited to SiO ₂ but may be made of other dielectric materials.

In this configuration, by providing the passivation film 40 between the p-side contact electrode 25 and the n-electrode 27, the Au bump 28 on the n-electrode 127 is crushed in a glass sealing process in which pressure acts at a high temperature. When it protrudes to the side contact electrode 25 side, it functions as an insulating member. In addition, since the passivation film 40 is not formed in the other regions, similarly to the embodiment, it is possible to suppress an increase in Vf of the LED element 2 when the heat treatment at the time of glass sealing is performed. And the reliability of the apparatus can be improved. In addition, in the portion where the passivation film 40 is formed, light emission to the element mounting substrate 3 side is suppressed by interface reflection due to the refractive index difference between ITO and SiO ₂ .

  In the above embodiment, the p-side pad electrode 26 and the n-electrode 27 are arranged opposite to each other. For example, the p-side pad electrode that is circular in plan view and the square in plan view are used. N electrodes exhibiting the above may be arranged diagonally on the LED element, and the shapes and arrangement of the p and n electrodes are arbitrary.

  In the above-described embodiment, the surface of the p-side contact electrode 25 is formed to be substantially flat. However, the surface of the p-side contact electrode 25 is intentionally roughened for the purpose of improving the light extraction efficiency. You may form in. Furthermore, although what used the LED element 2 as a light emitting element was shown, a solid element is not limited to an LED element, For example, an LD element etc. may be sufficient, and also about a specific detailed structure etc. suitably Of course, it can be changed.

It is a schematic model longitudinal cross-sectional view of the light-emitting device which shows one Embodiment of this invention. It is a bottom view of the LED element which shows an electrode formation part. The LED element having the passivation film formed on the entire surface of the electrode forming part and the LED element having no passivation film formed thereon were both heated for a predetermined time, and then the LED element was caused to emit light at a predetermined energizing current. It is a graph which shows the change of the forward voltage (Vf) at the time. It is a graph which shows the relationship between the heating temperature of a LED element, and the change of the forward voltage (Vf) at the time of making a LED element light-emit with a predetermined energization current. It is a schematic model longitudinal cross-sectional view of the light-emitting device which shows a modification. It is a bottom view of the LED element which shows a modification and shows an electrode formation part. It is a bottom view of the LED element which shows a prior art example and shows an electrode formation part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 2 LED element 2a Electrode formation part 2b Passivation film formation area 2c Passivation film non-formation area 3 Element mounting substrate 3a 1st layer 3b 2nd layer 3c Stepped part 4 Glass sealing part 5 Hollow part 20 Sapphire substrate 21 AlN Buffer layer 22 n-GaN layer 23 MQW layer 24 p-GaN layer 25 p-side contact electrode 26 p-side pad electrode 27 n-electrode 27a Al layer 27b Ni layer 27c Au layer 28 Au bump 30 Ni layer 31 Au layer 32 Circuit pattern 33 Via hole 34 Via pattern 35 External wiring pattern 36 W layer 40 Passivation film

Claims (6)

A light emitting element having an electrode forming portion provided with an electrode;
A mounting portion on which the light emitting element is mounted;
A glass sealing part formed on the mounting part, sealing the light emitting element and having a glass transition point of 340 ° C. or higher,
A light-emitting device, wherein a passivation film is not formed on the electrode forming portion of the light-emitting element. A light emitting element having an electrode forming portion provided with an electrode;
A mounting portion on which the light emitting element is mounted;
A glass sealing portion formed on the mounting portion, sealing the light emitting element, having a glass transition point of 340 ° C. or higher;
A light emitting device comprising: a hollow portion formed between the mounting portion and the light emitting element and in direct contact with the electrode of the light emitting element. A light emitting element having an electrode forming portion provided with a pair of electrodes;
A mounting portion on which the light emitting element is mounted;
A glass sealing part formed on the mounting part, sealing the light emitting element and having a glass transition point of 340 ° C. or higher,
The light-emitting device, wherein the electrode forming portion includes a passivation film forming region that is interposed between the electrodes and in which a passivation film is formed, and a passivation film non-forming region in which a passivation film is not formed.   The light emitting device according to claim 1, wherein the electrode of the light emitting element includes a conductive oxide.   The light emitting device according to claim 4, wherein the electrode of the light emitting element includes ITO (Indium Tin Oxide).   The light emitting device according to claim 1, wherein the light emitting element is a flip-chip mounted GaN-based LED element.

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