JP5008262B2 - Semiconductor light emitting device - Google Patents

Description

  The present invention relates to a semiconductor light emitting device, and more particularly to improvement of an electrode in a semiconductor light emitting device.

2. Description of the Related Art Conventionally, in a flip chip type nitride semiconductor light emitting device, a configuration in which an electrode made of silver or a silver alloy is formed as a p electrode has been used. Since silver reflects light generated in the light emitting layer of the light emitting element with high efficiency, a light emitting element with high luminance can be realized.
However, when silver is used as the p-side electrode material, it is necessary to expose a part of the surface of the silver electrode for connection to the outside, etc., which causes migration and promotes. As a result, there is a problem that the emission intensity and the lifetime are reduced.

Therefore, in order to prevent the exposure of the silver electrode surface, the silver electrode is completely covered with an electrode material not containing silver, or SiO having a plurality of through holes between the silver electrode and the electrode material not containing silver. A method for preventing silver migration by arranging _two films and electrically connecting a silver electrode and an electrode material not containing silver through the through-hole has been proposed (for example, Patent Document 1).

JP 2003-168823 A

However, there is a problem that silver cannot be sufficiently prevented from diffusing into an electrode material not containing silver by heat treatment after electrode formation or by the heat treatment conditions.
In addition, since the SiO ₂ film is disposed between the silver electrode and the electrode material not containing silver, although the electrical connection is ensured by the through hole, the contact resistance between the two increases. .

Furthermore, even if silver migration to the electrode material that does not contain silver is suppressed by physical blocking by the SiO ₂ film, it has not yet reached the point of effectively preventing silver migration to the nitride semiconductor layer, At present, it is still impossible to suppress a decrease in emission intensity and a decrease in lifetime of the light emitting element due to silver migration.

  The present invention has been made in view of the above problems, and in the case where a silver having a high reflection efficiency or an electrode mainly composed of silver is formed on a nitride semiconductor layer in contact with the nitride semiconductor layer, An object is to obtain a highly reliable and high-quality semiconductor light-emitting device by effectively preventing migration.

  The inventors of the present invention, as a result of earnest research on silver migration of electrodes made of silver or silver alloy, as a result of silver migration in the electrode made of silver or silver alloy is in contact with other electrode materials and semiconductors, In addition to heat treatment in the contact state or energization in the contact state, the electric field strength at the time of energization and the slight moisture (humidity) around the semiconductor light emitting element act on the silver, It is found that the migration of silver can be dramatically avoided by reducing the electric field strength during energization and isolating the electrode made of silver or a silver alloy from moisture and humidity. The present invention has been completed.

That is, the semiconductor light emitting device of the present invention includes at least a first conductivity type semiconductor layer and a second conductivity type semiconductor layer, the first electrode connected to the first conductivity type semiconductor layer, and the second conductivity type. A second electrode connected to a type semiconductor layer, wherein the first electrode and the second electrode are arranged on the same surface side of the first conductivity type semiconductor layer,
(1) The second electrode includes a first metal film containing silver or a silver alloy, and a second metal film that covers the first metal film and is made of a metal different from silver, and the first electrode. a first region facing the, and a second region which is a region other than the first region, or one prior SL end and a second metal layer of the first metal layer in at least a portion of the first region The distance to the end is set to be larger than the distance in the second region, or
(2) The second electrode includes a first metal film containing silver or a silver alloy, and a second metal film that covers the first metal film and is made of a metal different from silver, and the second metal. The film is disposed so as to cover a part of the second conductive semiconductor layer exposed from the first metal film, and the width of the film covering the second conductive semiconductor layer in the region facing the first electrode is It is characterized by being larger than the width in the region facing the edge of the semiconductor element.

In such a semiconductor light emitting device, the second metal film is disposed in contact with the second conductive semiconductor layer exposed from the first metal film, and the contact resistance with the second conductive semiconductor layer is the first. The contact resistance with one metal film is preferably larger.
The first conductive semiconductor layer and the second conductive semiconductor layer are preferably nitride semiconductor layers.
Furthermore, it is preferable that the insulating film having a nitride covering at least a part of the second metal film is at least one selected from the group consisting of silicon nitride or silicon nitride oxide.
The first metal film is preferably formed of a laminated film of at least a film made of silver or a silver alloy and a metal film that does not substantially react with silver disposed on the film.
Furthermore, it is preferable that the first conductive semiconductor layer is an n-type semiconductor layer and the second conductive semiconductor layer is a p-type semiconductor layer.

  According to the semiconductor light emitting device of the present invention, since the first metal film made of silver or a silver alloy is covered with the second metal film, contact between the first metal film made of silver or the silver alloy and moisture is prevented. Can be prevented. In addition, at least in the first region facing the first electrode, the distance from the end of the first metal film to the end of the second metal film is larger than that of the second region, or opposed to the first electrode. Since the width of the second metal film covering the second conductivity type semiconductor layer in the region to be processed is larger than the width in the region facing the edge of the semiconductor element, the first and second electrodes are arranged on the same surface side. In this case, the strength of the electric field strength in a partial region can be reduced. As a result, Ag migration and leakage current in the semiconductor light emitting device using the first metal film containing silver can be effectively prevented, the emission intensity is improved, the lifetime is increased, and the reliability is high. It is possible to obtain a semiconductor light emitting device.

  In particular, the second metal film is disposed in contact with the second conductive semiconductor layer exposed from the first metal film, and the contact resistance with the second conductive semiconductor layer is greater than the contact resistance with the first metal film. In the case of being large, the current flowing through the second metal film immediately flows into the first metal film, and further flows from the first metal film to the second conductivity type semiconductor layer, so that the semiconductor layer is directly below the first metal film. Can be sufficiently supplied, and the light emission efficiency can be improved. Moreover, since the light generated there can be efficiently reflected by the silver constituting the first metal film, the light emission efficiency can be further improved.

  Further, by using a specific nitride as the insulating film, it is possible to easily form the insulating film only by performing a normal manufacturing process, and in addition, moisture or moisture acting on Ag migration of the silver electrode By avoiding this, the above effect can be realized more remarkably.

  As described above, the semiconductor light emitting device of the present invention includes a semiconductor layer in which a first conductivity type semiconductor layer (hereinafter sometimes simply referred to as “semiconductor layer”) and a second conductivity type semiconductor layer are stacked in this order; The first and second electrodes are connected to the first and second conductivity type semiconductor layers, respectively. In general, a light emitting layer is disposed between the first and second conductive semiconductor layers.

  Here, the one conductivity type indicates p-type or n-type, and the second conductivity type indicates a conductivity type different from the first conductivity type, that is, n-type or p-type. Preferably, the first conductivity type semiconductor layer is n-type, and the second conductivity type semiconductor layer is p-type. These semiconductor layers are usually formed on a substrate.

As the substrate, for example, a known insulating substrate and conductive substrate such as sapphire, spinel, SiC, GaN, GaAs or the like can be used. Of these, a sapphire substrate is preferable.
The insulating substrate may be finally removed or may not be removed. When removing the insulating substrate, the p electrode and the n electrode may be formed on the same surface side or may be formed on different surfaces. When the insulating substrate is not removed, both the p electrode and the n electrode are usually formed on the same surface on the semiconductor layer.

The semiconductor layer is not particularly limited, the nitride semiconductor, for _{example, In X Al Y Ga 1-} XY N (0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is a gallium nitride-based compound such as a semiconductor Preferably used. The semiconductor layer may have a single layer structure, but may have a laminated structure such as a homo structure, a hetero structure, or a double hetero structure having a MIS junction, a PIN junction, or a PN junction, and has a superlattice structure or a quantum effect. It may be a single quantum well structure or a multiple quantum well structure in which the resulting thin films are stacked. Further, either n-type or p-type impurities may be doped. This semiconductor layer can be formed by a known technique such as metal organic chemical vapor deposition (MOCVD), hydride vapor deposition (HVPE), molecular beam epitaxy (MBE), or the like. The thickness of the semiconductor layer is not particularly limited, and various thicknesses can be applied.

Examples of the laminated structure of the semiconductor layers include those shown in the following (1) to (5).
(1) A buffer layer (thickness: 200 mm) made of GaN, an n-side contact layer (4 μm) made of Si-doped n-type GaN, a light emitting layer (30 mm) having a single quantum well structure made of undoped In _0.2 Ga _0.8 N, A p-type cladding layer (0.2 μm) made of Mg-doped p-type Al _0.1 Ga _0.9 N, and a p-side contact layer (0.5 μm) made of Mg-doped p-type GaN.

(2) A buffer layer (thickness: about 100 mm) made of AlGaN, an undoped GaN layer (1 μm), an n-side contact layer (5 μm) made of GaN containing Si of 4.5 × 10 ¹⁸ / cm ³ , and made of undoped GaN An n-side first multilayer film layer composed of three layers: a lower layer (3000 Å), an intermediate layer (300 Å) made of GaN containing Si of 4.5 × 10 ¹⁸ / cm ³ , and an upper layer (50 Å) made of undoped GaN ( Total thickness: 3350 mm), undoped GaN (40 mm) and undoped In _0.1 Ga _0.9 N (20 mm) are repeatedly stacked alternately in 10 layers, and further, undoped GaN (40 mm) is stacked on the n-side first layer 2 multilayer layers (total film thickness: 640 mm), barrier layers (250 mm) made of undoped GaN and well layers (30 mm) made of In _0.3 Ga _0.7 N are alternately repeated 6 Light emitting layer (total film thickness: 1930Å) having a multilayered structure in which barrier layers (250Å) made of undoped GaN are further laminated, Al _0.15 Ga _0.85 N containing 5 × 10 ¹⁹ / cm ³ Mg ( 40 Å) and a Mg containing ^{5 × 10 19 / cm 3 in} 0.03 Ga 0.97 N (25Å) Al 0.15 includes a repeating five layers each 5 × 10 ¹⁹ / cm ³ further Mg are laminated alternately Ga _0.85 N (40 Å P-side multilayer film layer (total film thickness: 365 mm) having a superlattice structure, and p-side contact layer (1200 mm) made of GaN containing 1 × 10 ²⁰ / cm ^{3 of} Mg.

(3) AlGaN buffer layer (film thickness: about 100 mm) undoped GaN layer (1 μm), n-side contact layer (5 μm) made of GaN containing 4.5 × 10 ¹⁸ / cm ³ Si, lower layer made of undoped GaN (3000 Å), an n-side first multilayer film layer (total of 3 layers of an intermediate layer (300 Å) made of GaN containing Si of 4.5 × 10 ¹⁸ / cm ³ and an upper layer (50 Å) made of undoped GaN (total) Film thickness: 3350Å), undoped GaN (40Å) and undoped In _0.1 Ga _0.9 N (20Å) are alternately and repeatedly stacked 10 layers each, and the n-side second of the superlattice structure in which undoped GaN (40Å) is further stacked Multilayer (total thickness: 640 mm), barrier layer (250 mm) made of undoped GaN, well layer (30 mm) made of In _0.3 Ga _0.7 N, and In _0.02 Ga _0.98 N A light emitting layer having a multiple quantum well structure (total film thickness: 1930 Å) formed by repeatedly stacking six layers of first barrier layers (100 Å) and second barrier layers (150 Å) made of undoped GaN repeatedly and alternately. (a layer to be laminated to the repeated alternately is preferably from 3 layers to 6 layers), an in _0.03 comprising Al _0.15 Ga _0.85 N (40Å) and a Mg 5 × 10 ¹⁹ / cm ³ containing Mg 5 × 10 ¹⁹ / cm ³ A p-side multilayer layer having a superlattice structure in which five layers of Ga _0.97 N (25 繰 り 返 し) are alternately laminated and Al _0.15 Ga _0.85 N (40Å) containing 5 × 10 ¹⁹ / cm ^{3 of} Mg is further laminated ( Total film thickness: 365 mm), p-side contact layer (1200 mm) made of GaN containing 1 × 10 ²⁰ / cm ^{3 of} Mg.

Of these, the lower layer (3000 Å) made of undoped GaN provided on the n side is the first layer (1500 Å) made of undoped GaN from the bottom, and the second layer made of GaN containing 5 × 10 ¹⁷ / cm ^{3 of} Si. By making the lower layer of a three-layer structure consisting of (100Å) and a third layer (1500Å) made of undoped GaN, it becomes possible to suppress the variation in _{Vf with} the lapse of the driving time of the light emitting element.

  Further, GaN or AlGaN (2000 mm) may be formed between the p-side multilayer film layer and the p-side contact layer. This layer is undoped and exhibits p-type due to diffusion of Mg from adjacent layers. By providing this layer, the electrostatic withstand voltage of the light emitting element is improved. This layer may be omitted when used in a light emitting device provided with an electrostatic protection function separately, but when an electrostatic protection means such as an electrostatic protection element is not provided outside the light emitting element, an electrostatic withstand voltage is not required. Since it can improve, providing is preferable.

(4) Buffer layer, undoped GaN layer, n-side contact layer made of GaN containing 6.0 × 10 ¹⁸ / cm ^{3 of} Si, undoped GaN layer (the above is an n-type nitride semiconductor layer with a total film thickness of 6 nm), Si 5 × 10 ¹⁸ / cm ^{3 of} GaN barrier layers and InGaN well layers are repeatedly stacked in a multiple quantum well light emitting layer (total film thickness: 1000 Å), Mg is 5.0 × 10 5 ^A p-type nitride semiconductor layer (film thickness: 1300 mm) made of GaN containing ¹⁸ / cm ³ .

  Furthermore, an InGaN layer (30 to 100 mm, preferably 50 mm) may be provided on the p-type nitride semiconductor layer. Thereby, this InGaN layer becomes a p-side contact layer in contact with the electrode. Thus, even a layer not doped with Mg functions as a p-type nitride semiconductor layer for forming a p-electrode if the film thickness is relatively smaller than that of an adjacent p-type semiconductor layer.

(5) Buffer layer, undoped GaN layer, n-side contact layer made of GaN containing 1.3 × 10 ¹⁹ / cm ^{3 of} Si, undoped GaN layer (the above is an n-type nitride semiconductor layer having a total film thickness of 6 nm), Si Is a multiple quantum well light emitting layer (total film thickness: 800 mm) in which 7 layers of GaN barrier layers and InGaN well layers containing 3.0 × 10 ¹⁸ / cm ³ are alternately stacked, and Mg is 2.5 × 10 ^A p-type nitride semiconductor layer made of GaN containing ²⁰ / cm ³ . On this p-type nitride semiconductor layer, an InGaN layer (30 to 100 mm, preferably 50 mm) may be formed as a p-side contact layer.

  The semiconductor light emitting element constituted by these semiconductor layers is generally square or substantially similar in shape in plan view, and the first conductivity type semiconductor layer is a part of one semiconductor light emitting element. The two-conductivity type semiconductor layer and the light emitting layer, and optionally a part of the first semiconductor layer in the depth direction are removed, and the surface thereof is exposed.

  For example, as shown in FIG. 3A, a shape in which the first conductive semiconductor layer N is exposed by removing a part of the second conductive semiconductor layer P and the like in a region facing one side of the light emitting element H, 3 (b), a shape in which the first conductive semiconductor layer N is exposed by removing a part of the second conductive semiconductor layer P, etc. in a region facing one corner of the light emitting element H, As shown in (c), (d) to FIG. 4 (h), the second conductive type semiconductor layer P or the like is removed in the outer periphery and / or a partial region inside the light emitting element H, and the first conductive type semiconductor layer is removed. Any shape such as a shape where N is exposed may be used. In one semiconductor element, the exposed area of the first conductivity type semiconductor layer and the area of the second conductivity type semiconductor layer can be set to about 1: 1 to 4, for example.

A first electrode is formed on the exposed surface of the first conductive type semiconductor layer.
The material and film thickness of the first electrode are not limited, and can usually be formed of a single layer film or a laminated film of a conductive material that can be used as an electrode. In addition, it is preferable that the 1st electrode is arrange | positioned apart from the 2nd conductivity type semiconductor layer. These distances can be appropriately adjusted according to the size of the semiconductor light emitting element to be obtained, the materials, sizes, and arrangements of the first electrode and the second electrode. The shortest distance between the first electrode and the second semiconductor layer is, for example, about 1 μm or more and about 3 to 10 μm.

A second electrode is formed on the surface of the second conductivity type semiconductor layer. Therefore, the first electrode and the second electrode are arranged on the same plane in plan view.
The second electrode is preferably in direct contact with the second conductivity type semiconductor layer and is ohmic-connected. Here, the ohmic connection has a meaning normally used in the field, and refers to, for example, a junction whose current-voltage characteristic is a straight line or a substantially straight line. It also means that the voltage drop and power loss at the junction during device operation are negligibly small.

  The second electrode includes a first metal film made of silver or a silver alloy and a second metal film that covers the first metal film. The first metal film is ohmic-connected to the second semiconductor layer and is intended to efficiently input current and to reflect light from the light emitting layer efficiently. As long as the relationship between the two-conductivity type semiconductor layer and the second metal film is satisfied, it is preferably formed on a substantially entire surface of the second semiconductor layer with a large area.

The first metal film may be a silver single layer film, a silver alloy single layer film, or a laminated film containing silver or a silver alloy in the lowermost layer.
The silver alloy is selected from the group consisting of silver and Pt, Co, Au, Pd, Ti, Mn, V, Cr, Zr, Rh, Cu, Al, Mg, Bi, Sn, Ir, Ga, Nd and Re. And an alloy with one or more electrode materials. Ni is difficult to be alloyed with silver, but the silver film may contain Ni element.

The composition of the first metal film may be inclined from the semiconductor layer side to the second metal film side. For example, it may be a silver film or an alloy containing silver and an element other than silver up to about 1% on the semiconductor side, and silver and an element other than silver up to about 5% on the second metal film side. An alloy containing
The film other than the lowermost layer may be silver or a silver alloy, or may be formed of an electrode material that does not contain silver or a silver alloy. Further, the films other than the lowermost layer substantially do not react with silver, a single layer film of two or more kinds of metal or alloy selected from the group including these electrode materials and Ni, or a laminated film of two or more layers. A metal film or the like is preferable.

  A preferred example of the first metal film is a single layer film of silver, and further has a two-layer structure of metal (upper) / silver or silver alloy (lower) that does not substantially react with silver, noble metal (upper) / silver Or a two-layer structure of silver alloy (lower), a three-layer structure of a metal (medium) / silver or silver alloy (lower) that does not substantially react with noble metal (upper) / silver, a noble metal two-layer (upper) / substantially silver and A 4-layer structure of metal (medium) / silver or silver alloy (bottom) that does not react automatically is more preferable. Examples of the noble metal include platinum group metals and gold. Among them, Pt and gold are preferable.

  As a metal that does not substantially react with silver, a metal that does not substantially react with silver at a temperature of 1000 ° C. or less, specifically, nickel (Ni), ruthenium (Ru), osmium (Os), iridium (Ir) , Titanium (Ti), vanadium (V), niobium (Nb), tantalum (Ta), cobalt (Co), iron (Fe), chromium (Cr), tungsten (W), and the like. Of these, Ni is preferable.

  The film thickness of the first metal film is not particularly limited. For example, in the case of a silver or silver alloy single layer, the film thickness that can effectively reflect light from the light emitting layer, specifically, about 200 to 1 μm, About 500 to 3000 mm, preferably about 1000 mm. In the case of a laminated structure, the total film thickness is about 500 to 5 μm and about 500 to 1 μm, and the silver or silver alloy film contained therein can be appropriately adjusted within this range. In the case of a laminated structure, the silver or silver alloy film and the film laminated thereon may have the same shape by patterning in the same process, but the lowermost silver or silver alloy film It is preferable to coat with a film laminated thereon (preferably a metal film that does not react with silver). As a result, no matter what electrode material is formed as a part of the first metal film on the metal film that does not react with silver, it does not come into direct contact with the silver or silver alloy film. Can be blocked.

  Depending on the stacked state of the first metal film, the first metal film may be crystallized at least at the interface with the semiconductor layer, for example, when a nickel film is disposed immediately above the silver single layer film. By crystallization of the first metal film, better ohmic properties with the semiconductor layer can be ensured. Here, crystallization is, for example, a method of observing a cross section by transmission electron microscopy (TEM), a method of observing by scanning electron microscopy (SEM), a method of measuring an electron diffraction pattern, or an ultra-thin film evaluation apparatus. It means that the interface of crystal grains can be visually recognized by an observation method or the like. It is preferable that the crystal grains in this case can be visually recognized as having a diameter (length, height, or width) of about 10 to 100 nm, for example.

  The first metal film is crystallized at the interface with the semiconductor layer by a known method such as vapor deposition, sputtering, ion beam assisted vapor deposition, etc. The method of heat-processing in the temperature range of about 300-600 degreeC for about 10 to 30 minutes under a nitrogen atmosphere is mentioned.

  The second metal film may be in any form as long as it covers at least a part of the first metal film. However, the second metal film completely or substantially completely covers the first metal film, It is preferable that part of the upper surface of the conductive semiconductor layer is in contact (or covered). “Completely or substantially completely covered” means that the second metal film is not subjected to processing that positively exposes the first metal film. Therefore, it is more preferable that all of the upper surface and the entire side surface of the first metal film are substantially covered.

  Since the second electrode is intended to efficiently reflect the light from the light emitting layer as described above, the second electrode satisfies the relationship with the second conductivity type semiconductor layer and the first metal film, which will be described later. As long as the first metal film is formed, it is preferably formed on a substantially entire surface on the second conductivity type semiconductor layer in a wide area. Thereby, light from the light emitting layer can be extracted with high efficiency. However, the second metal film does not necessarily completely or substantially completely cover the first metal film, and is formed on a part of the surface and / or side surface of the first metal film, such as a normal pad electrode. May be. Alternatively, the second metal film that completely or substantially completely covers the first metal film may be formed as a so-called cover electrode, and a pad electrode or the like may be further formed thereon. When the pad electrode is provided, it may be provided in contact with at least the p electrode, or may be provided in contact with each of the p electrode and the n electrode. When both the insulating film and the pad electrode are formed, the pad electrode may be formed after the insulating film is formed, or the insulating film may be formed after the pad electrode is formed. That is, a part of the pad electrode may be in contact with the p electrode through the insulating film, or the entire surface of the pad electrode may be in contact with the p electrode.

The second metal film is made of a metal different from silver. For example, zinc (Zn), nickel (Ni), platinum (Pt), palladium (Pd), rhodium (Rh), ruthenium (Ru), osmium (Os), iridium (Ir), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), cobalt (Co), iron (Fe), manganese (Mn), molybdenum (Mo), chromium (Cr), tungsten (W), lanthanum (La), copper (Cu), silver (Ag), yttrium (Y), gold (Au), aluminum (Al), etc. Examples thereof include a single layer film or a laminated film of a conductive oxide film such as metal, alloy, ITO, ZnO ₂ , and SnO.

For example, a Pt single layer film, a two-layer structure film of Au (upper) / Pt (lower), a three-layer structure film of Pt (upper) / Au (middle) / Pt (lower), and the like are preferable.
Further, when the first metal film is a single layer film of silver or a silver alloy, as described above, the metal that does not substantially react with silver is in the region of the second metal film that is in contact with at least the first metal film. It is preferable to arrange.
Furthermore, when the first metal film is formed as a laminated film that does not contain silver or a silver alloy in the uppermost layer, the second metal film preferably contains titanium, and the lowermost layer of the second metal film It is preferable to dispose a titanium film.

  Moreover, it is preferable to arrange a conductive material usually used for connection with other terminals such as wire bonding, such as gold or platinum, on the upper surface (connection region) of the second metal film on these electrodes. . Furthermore, it is preferable to dispose a material having good adhesion to the insulating film described later on the upper surface of the second metal film.

  The film thickness of the second metal film is not particularly limited. For example, when an Au bump is formed on the second metal film, the second metal film is made relatively thick and an eutectic (Au—Sn, etc.) bump is formed. Specifically, it is preferable to adjust the thickness of the second metal film so that the total film thickness is about 100 to 1000 nm.

  In the semiconductor light emitting device of the present invention, it is preferable that at least the second electrode has a first region and a second region. Alternatively, it is preferable to have a region facing the first electrode and a region facing the edge of the light emitting element. The distance between the end of the first metal film and the end of the second metal film in at least a part of the first region is preferably set to be smaller than the distance in the second region. Alternatively, the width of the second metal film in contact with the second conductivity type semiconductor layer (covering the second conductivity type semiconductor layer) in the region facing the first electrode is the width in the region facing the edge of the semiconductor element. Is preferably larger. However, when there are a plurality of first electrodes, the region where the distance between the end portion of the first metal film and the end portion of the second metal film is reduced, or the width covering the second conductivity type semiconductor layer is increased. The region may be only in a part of the region facing the first region or the first electrode.

  Here, the first region refers to a region adjacent to the edge of the second electrode or the second metal film facing the first electrode. For example, in the semiconductor light emitting device, the second region refers to a region that does not oppose the first electrode among regions adjacent to and including the edge of the second electrode or the two metal films. In other words, the second region is a region facing the edge of the light emitting element. For example, as shown in FIG. 3A to FIG. 4H, in the semiconductor light emitting device H, the first electrode E in the region including the edge of the second electrode or the two metal films and adjacent thereto. For example, a second region b, that is, a region other than the first region, that is, a region not facing the first electrode E or a region facing the edge of the light emitting element. Preferably it is. In FIG. 3A to FIG. 4H, the second electrode formed on the second conductive semiconductor layer P is omitted, and the first electrode formed on the first conductive semiconductor layer N is omitted. Only E is shown.

  In addition, the distance from the first metal film end to the second metal film end is, for example, as shown in FIG. 1A, on the second conductivity type semiconductor 5, as the second electrode, A semiconductor in which a first metal film 6 and a second metal film 7 are formed so as to completely cover the first metal film 6, and a first electrode 9 is formed on the exposed surface of the first conductivity type semiconductor 3. In the light emitting element 1, when the distances La and Lb from the first metal film 6 end to the second metal film 7 end are compared in the first region a and the second region b, La> Lb. Indicates. Here, the lengths of La and Lb can be appropriately adjusted according to the size of the element, the material and film thickness of the first metal film and the second metal film, etc. For example, La is about 5 to 10 μm, and Lb is About 2 to 5 μm is appropriate, and the difference between the two is preferably about 3 to 5 μm. The distances La and Lb can be rephrased as the width of the second metal film covering the second conductive type semiconductor layer in the region facing the first region and the width of the covering region at the edge of the semiconductor element, respectively.

  Furthermore, at least in the first region, it is preferable that the distance from the end portion of the first metal film to the end portion of the second conductivity type semiconductor layer is larger than that in the second region. That is, in FIG. 1A, when comparing the distances Ma and Mb from the first metal film 6 end to the second conductivity type semiconductor layer 5 end in the first region a and the second region b, It shows that Ma> Mb. The lengths of Ma and Mb here can be appropriately adjusted according to the size of the element, the material and film thickness of the first metal film and the second metal film, etc. For example, Ma is about 7 to 15 μm, and Mb is About 4 to 10 μm is appropriate, and the difference between the two is preferably about 3 to 5 μm.

The semiconductor light emitting device of the present invention preferably further includes an insulating film that covers a part of the second metal film. For example, the insulating film may be formed so as to cover part or all of the outer periphery of the second metal film and to cover part or all of the upper surface and / or the side surface of the first and second semiconductor layers. More preferred. As the insulating film, an oxide film (Al ₂ O ₃ ) and a nitride film are preferably used, and a nitride film is more preferable. A typical example of the nitride film is a single-layer film or a laminated film such as SiN, TiN, or SiO _x N _y . Among these, a single layer film of SiN or the like is preferable. In this way, by using a film containing N instead of a film with relatively high water content such as SiO ₂ as the insulating film covering the electrode, nitrogen atoms capture water or moisture, and silver and silver alloys It is considered that moisture or moisture to the electrode made of is effectively prevented, and migration of silver can be prevented.
The insulating film does not need to completely cover the electrode, and the electrode is preferably covered except for a region necessary for connection with another terminal. The film thickness of the insulating film is suitably about 400 to 1000 nm, for example.

  In the semiconductor light emitting device of the present invention, it is preferable that a plurality of irregularities be formed at least in the exposed region where the first electrode is not formed (including the outer edge portion of the semiconductor light emitting device). In other words, as will be described later, even if a light emitting layer is present, holes and electrons are not supplied, so that it does not function as a light emitting layer and a plurality of irregularities are formed in a region that does not emit light itself. Is preferred.

  Thus, by forming the unevenness, (1) the light guided in the first semiconductor layer is taken into the convex portion, and is extracted from the top of the convex portion or the middle portion thereof. (2) The light guided in the first semiconductor layer is irregularly reflected and extracted at the root of the convex portion, and (3) the light emitted laterally from the end surface of the light emitting layer is reflected and scattered by the plurality of convex portions and extracted. In other words, the light emitted in the lateral direction (side surface direction of the semiconductor light emitting element) can be selectively emitted to the second semiconductor layer side by the unevenness, whereby the light extraction efficiency is, for example, 10 to 10%. It can be improved by about 20%, and the light directivity can be controlled. In particular, in a semiconductor light emitting device having a structure in which a light emitting layer is sandwiched between layers having a lower refractive index (so-called double heterostructure), light is confined between the layers having a lower refractive index, so that the lateral direction is increased. This is particularly effective for a light emitting device having such a structure. Furthermore, by providing a plurality of projections and depressions, uniform light extraction can be performed over the entire region on the second semiconductor layer side.

  Concavities and convexities may be formed on the exposed first semiconductor layer by, for example, growing a semiconductor layer to perform a special process for forming a convex portion. However, when the first semiconductor layer is exposed or on each chip It is preferable that the predetermined regions are formed at the same time, for example, when a predetermined region is thinned for division. Thereby, the increase in a manufacturing process can be suppressed. As described above, the unevenness is composed of the same stacked structure as the semiconductor stacked structure of the semiconductor light-emitting element, that is, a plurality of layers made of different materials. Therefore, the light taken into the convex portion is caused by the difference in refractive index of each layer. It is considered that the light is easily reflected at the interface between the layers, and as a result, the light extraction toward the second semiconductor layer is improved.

  The convex portion in the unevenness may be higher than at least the interface between the light emitting layer and the first semiconductor layer adjacent thereto in the cross section of the semiconductor light emitting device, but the top portion is preferably located on the second semiconductor layer side of the light emitting layer. Furthermore, it is more preferable that the height is substantially the same as that of the second semiconductor layer. That is, it is preferable that the top of the convex portion is formed so as to be higher than the light emitting layer. By configuring the protrusions so as to include the second semiconductor layer, the tops thereof are substantially the same height, so that the second semiconductor layer side from the top of the protrusions is not obstructed by the second electrode or the like described later. Can effectively extract light. By configuring the convex portion to be higher than the second semiconductor layer, preferably the second electrode, light can be extracted more effectively. In addition, the concave portion between the convex portions may be at least lower than the interface between the light emitting layer and the second semiconductor layer adjacent thereto, and is preferably formed to be lower than the light emitting layer.

The density of the unevenness is not particularly limited, and in one semiconductor light emitting device, it can be at least 100, preferably 200, more preferably 300, more preferably 500. Thereby, the said effect can be improved more. Note that the ratio of the area occupied by the region where unevenness is formed as viewed from the electrode forming surface side can be 20% or more, preferably 30% or more, and more preferably 40% or more. The upper limit is not particularly limited, but is preferably 80% or less. The area of one of the projections, at the root of the protrusion, 3～300Myuemu ^2, preferably 6～80Myuemu ^2, more preferably be a 12~50μm ^2.

  The convex portion may have any shape such as a quadrangular shape, a trapezoidal shape, or a semicircular shape, but is preferably a trapezoidal shape, that is, a frustoconical shape in which the convex portion itself gradually narrows. In this case, the inclination angle of the convex portion is, for example, 30 ° to 80 °, and preferably 40 ° to 70 °. That is, by inclining the convex portion so that it gradually becomes thinner toward the tip, the light from the light emitting layer is totally reflected on the surface of the convex portion, or the light guided through the first semiconductor layer is scattered. As a result, light extraction toward the second semiconductor layer can be effectively performed. In addition, the directivity control of light becomes easier and more uniform light extraction is possible as a whole.

In addition, when a convex part is truncated cone shape, the recessed part may be further formed in the upper side (2nd semiconductor layer side) of trapezoid. Thereby, when the light guided in the first semiconductor layer enters the inside of the convex portion, the concave portion formed at the top of the convex portion facilitates light to be emitted toward the second semiconductor layer side.
Furthermore, it is preferable that the convex portions are arranged to be at least partially overlapped by 2 or more, preferably 3 or more, in a direction substantially perpendicular to the emission end face of the semiconductor multilayer structure. Thereby, the light from the light emitting layer is allowed to act on the convex portion with a high probability, so that the above effect can be obtained more easily.

The semiconductor light-emitting device of the present invention is usually mounted on a support substrate by flip chip mounting (face-down mounting) to constitute a semiconductor light-emitting device.
The support substrate may be provided with wiring on at least a surface facing the electrode of the light emitting element, and a protective element or the like may be arbitrarily formed, and fixes and supports the light emitting element mounted in flip chip. The support substrate is preferably made of a material having substantially the same thermal expansion coefficient as that of the light emitting element, for example, aluminum nitride for the nitride semiconductor light emitting element. Thereby, the influence of the thermal stress which generate | occur | produces between a support substrate and a light emitting element can be relieve | moderated. Further, silicon that can be added with a function such as an electrostatic protection element and is inexpensive may be used. The wiring pattern is not particularly limited. For example, it is preferable that a pair of positive and negative wiring patterns be insulated and separated so as to surround one another.
When the support substrate is connected to the lead electrode, wiring may be provided by a conductive member from the surface facing the light emitting element to the surface facing the lead electrode.

  As the support substrate having the function of the protection element, for example, an n-type silicon substrate of an Si diode element can be used. By selectively implanting impurity ions into the n-type silicon substrate, one or more p-type semiconductor regions are formed, and the reverse breakdown voltage is set to a predetermined voltage. Then, a p electrode and an n electrode are formed on the p type semiconductor region and the n type semiconductor region (n type silicon substrate itself) of the silicon substrate. Some of these p-electrode and n-electrode can be used as bonding pads. Alternatively, an n electrode made of Au or the like may be formed on the lower surface of the n-type silicon substrate to form a bonding pad. In the semiconductor region, an electrode having a function of a reflective film made of a silver-white metal material (for example, Al or Ag) may be formed as a p electrode and / or an n electrode.

  When mounting a semiconductor light emitting element on a support substrate, for example, a bump made of Au or the like is placed on the support substrate, or the p electrode and / or the n electrode in the protection element described above is used as a bump, thereby providing the semiconductor light emitting element. The p-electrode and n-electrode are opposed to the bumps or electrodes formed on the support substrate, and are electrically and mechanically connected. The connection can be performed by ultrasonic bonding and / or heat treatment with a bonding member such as Au, eutectic material (Au—Sn, Ag—Sn), solder (Pb—Sn), lead-free solder, or the like. When the wiring and the lead electrode are configured to be directly connected, for example, a bonding member such as Au paste or Ag paste can be used. In the case of using Au as a bump, since connection is obtained by applying ultrasonic waves and heat, there is a risk of damaging the semiconductor layer in the light emitting element. Therefore, as the second metal film of the semiconductor light emitting element, An Au (upper) / Pt (lower) film is preferably formed. Further, when the eutectic material is used as a bump, since only heat is applied, an Au film may be formed as the second metal film, or the first metal film may be a single layer film of Ag. When bumps are used, it is preferable that the bump area is large and the number is large. Accordingly, heat dissipation from the light emitting element can be improved, and the bonding strength of the light emitting element to the support substrate can be increased.

  In the case where a protective element (for example, a diode) is formed on the support substrate, the semiconductor light emitting element and the protective element include a bidirectional diode formed by connecting two diodes in series and a parallel connection of the semiconductor light emitting element. It is preferable to do. As a result, the semiconductor light emitting element can be protected from overvoltage in the forward direction and the reverse direction, and can be a highly reliable semiconductor device.

  The light-emitting element of the present invention preferably has a light conversion member that converts part of light from the light-emitting element into light having a different wavelength. The light conversion member is configured to include at least a fluorescent material that is excited by a light emission wavelength from the light emitting element and emits fluorescent light, or includes a fluorescent material and a binder, and optionally an inorganic member (glass, filler, etc.). The Thereby, the light of the light emitting element is converted, the light from the light emitting element is mixed with the converted light and the fluorescent light, for example, white light whose chromaticity is located on the locus of black body radiation in the chromaticity diagram, It is possible to obtain a light emitting device that emits desired light such as a white color or a light bulb color such as light having a special color rendering index R9 of around 40 at a color temperature of Tcp = 4600K.

  In general, the light conversion member is preferably disposed on the light extraction surface side. For example, the light conversion member includes a fluorescent material, a sealing member that covers a light emitting element to be described later, a die bond material that fixes the submount on which the light emitting element is flip-chip mounted to another support, and the periphery of the light emitting element and the supporting substrate. It can be formed by arranging in and / or around each constituent member such as a support layer such as a resin layer, a submount and a package provided on the substrate. When a plurality of light emitting elements are mounted on one support substrate, they may be arranged in a gap between the elements. In particular, when a fluorescent material is combined with a sealing member, it may be in the form of a sheet that covers the light emission observation surface side surface of the sealing member, and includes a phosphor at a position spaced from the surface and the light emitting element. A layer, a sheet, a cap, or a filter may be provided inside the sealing member. Further, when the light emitting element mounted on the flip chip is covered, it may be formed by a metal mask, screen printing, stencil printing or the like. Thereby, it can form easily with a uniform film thickness.

The light conversion member is a single layer of one kind of fluorescent substance, a single layer in which two or more kinds of fluorescent substances are uniformly mixed, and two or more layers of a single layer containing one kind or two or more kinds of fluorescent substances It can be formed as a laminated structure. In addition, when laminating two or more single layers, the fluorescent substance or the like contained in each layer may be one that converts the wavelength of light having the same wavelength into emitted light having the same wavelength, The incident light having the same wavelength may be converted into the outgoing light having a different wavelength.
In order to reduce color unevenness, it is preferable that the average particle diameter and the shape of each phosphor are comparable. The particle size of the phosphor can be measured by, for example, a volume reference particle size distribution curve described in JP-A No. 2004-207688.

  The light emission color of the light emitting device is selected by appropriately selecting the ratio of the phosphor, the binder, and optionally the inorganic member, the specific gravity of the phosphor, the amount and shape of the phosphor, the emission wavelength of the light emitting element, and the like. The temperature can be changed to obtain an arbitrary white color tone such as light in a light bulb color region. It is preferable that the light from the light emitting element and the light from the phosphor efficiently pass through the mold member outside the light emitting device.

Examples of fluorescent materials include:
(i) rare earth aluminate,
(ii) nitrides or oxynitrides,
(iii) alkaline earth silicate, alkaline earth silicon nitride,
(iv) alkaline earth metal halogen apatite,
(v) alkaline earth metal halogen borate,
(vi) alkaline earth metal aluminate,
(vii) sulfides,
(viii) alkaline earth thiogallate,
(ix) germanate,
(x) rare earth silicates,
(xi) Various fluorescent materials such as organic and organic complexes mainly activated with a lanthanoid element such as Eu. Any of these fluorescent substances can be used.

  In particular, (i) as the rare earth aluminate, those mainly activated by rare earth elements such as Ce, particularly lanthanoid elements, are preferable, and typically aluminum garnet series (particularly activated by cerium). Examples thereof include yttrium / aluminum / garnet phosphors (YAG) and lutetium / aluminum / garnet phosphors (LAG).

As the YAG fluorescent material, for example, those described in JP-A No. 2004-207688 are preferable. Specifically, considering the high brightness and the long-term _{use, (Re 1-x Sm x} ) 3 (Al 1-y Ga y) 5 O 12: Ce (0 ≦ x <1,0 ≦ y ≦ 1 However, Re is preferably at least one element selected from the group consisting of Y, Gd, and La). That is, this fluorescent substance can have an excitation spectrum peak near 470 nm or the like, and can have a broad emission spectrum near 530 nm and extending to 720 nm. In particular, this fluorescent material can increase RGB wavelength components by using a combination of materials having different contents of Al, Ga, Y, La and Gd, Sm. When a YAG phosphor is used, a light emitting device having sufficient light resistance with high efficiency even when used with a light emitting element having an irradiance of (Ee) = 0.1 W · cm ⁻² or more and 1000 W · cm ⁻² or less Can be obtained.

LAG phosphor is represented by the general formula _{(Lu 1-ab R a M} b) 3 (Al 1-c Ga c) 5 O 12 ( where, R represents an essential Ce, Ce, La, Pr, Nd, Sm, Eu , Gd, Tb, Dy, Ho, Er, Tm, Yb, Lr, and M is at least one element selected from Sc, Y, La, Gd, 0.0001 ≦ a ≦ 0.5, 0 ≦ b ≦ 0.5, 0.0001 ≦ a + b <1, 0 ≦ c ≦ 0.8.), For example, (Lu _0.99 Ce _{0.01) 3 Al 5 O 12,} (Lu 0.90 Ce 0.10) 3 Al 5 O 12, include _{(Lu 0.99 Ce 0.01) 3 (} Al 0.5 Ga 0.5) 5 O 12 and the like.

  Since the lutetium / aluminum / garnet phosphor is efficiently excited and emitted by ultraviolet rays or visible light in the wavelength region of 300 nm to 550 nm, it can be effectively used as a phosphor contained in the light conversion member. In addition, since the temperature characteristics are excellent, a light-emitting device with little deterioration and color shift can be obtained.

(Ii) The nitride or oxynitride contains N and at least one element selected from Be, Mg, Ca, Sr, Ba, and Zn, and C, Si, Ge, Sn, Ti, A fluorescent material containing at least one element selected from Zr and Hf is preferable. Moreover, what was activated with the at least 1 element selected from the rare earth elements is preferable. For example,
L _x J _y N _{((2/3) x + (4/3) y)} : R
L _x J _y O _z N _{((2/3) x + (4/3) y- (2/3) z)} : R
_{L x J y Q t O z} N ((2/3) x + (4/3) y + t- (2/3) z): R
(L is at least one group II element selected from the group consisting of Be, Mg, Ca, Sr, Ba, and Zn. J consists of C, Si, Ge, Sn, Ti, Zr, and Hf. At least one Group IV element selected from the group, Q is at least one Group III element selected from the group consisting of B, Al, Ga, and In, and R is Y, La, Ce Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Lu, Sc, Yb, Tm is at least one rare earth element, and L, J, and R are (X, y, and z are 0.5 ≦ x ≦ 3, 1.1.5 <y ≦ 8, 0 <t <0.5, and 0 <z ≦ 3.)
Is mentioned.

Furthermore, (iii) the alkaline earth silicate and the alkaline earth silicon nitride are preferably activated with europium, for example. For example,
(2-x-y) SrO · x (Ba, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: yEu 2+
(Where 0 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5).
(2-x-y) BaO · x (Sr, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: yEu 2+
(In the formula, 0.01 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.)
Etc.

The alkaline earth metal halogen apatite fluorescent material is preferably mainly activated by a lanthanoid-based element such as Eu and / or a transition metal-based element such as Mn. For example, M ₅ (PO ₄ ) ₃ X : R _E (M is at least one selected from Sr, Ca, Ba, Mg, Zn; X is at least one selected from F, Cl, Br, I; R _E is Eu and / or Mn.) And the like. For example, calcium chlorapatite (CCA), barium chloroapatite (BCA), Ca ₁₀ (PO ₄ ) ₆ FCl: Sb, Mn, etc. are exemplified.

Examples of the alkaline earth metal borate fluorescent substance include M ₂ B ₅ O ₉ X: R _E (M, X and R _E are as defined above). For example, calcium chlorborate (CCB) is exemplified.
The alkaline earth metal aluminate fluorescent material is preferably activated with europium and / or manganese. For example, europium activated strontium aluminate (SAE), barium magnesium aluminate (BAM), or SrAl ₂ O ₄ : _{R E, Sr 4 Al 14 O} 25: R E, CaAl 2 O 4: R E, BaMg 2 Al 16 O 27: R E, BaMgAl 10 O 17: R E, CaAl 2 O 4: Eu, BaMgAl 10 O 17 : Eu, Mn (R _E is Eu and / or Mn) and the like.

As alkaline earth silicate and alkaline earth silicon nitride,
Me (3-xy) MgSi ₂ O ₃ : xEu, yMn
(In the formula, 0.005 <x <0.5, 0.005 <y <0.5, Me represents Ba and / or Sr and / or Ca.)
Specifically, M ₂ Si ₅ N ₈ : Eu, MSi ₇ N ₁₀ : Eu, M _1.8 Si ₅ O _0.2 N ₈ : Eu, M _0.9 Si ₇ O _0.1 N ₁₀ : Eu
(M is at least one selected from Sr, Ca, Ba, Mg, Zn).

Examples of sulfides include alkaline earth sulfides such as CaS: Eu and SrS: Eu, La ₂ O ₂ S: Eu, Y ₂ O ₂ S: Eu, Gd ₂ O ₂ S: Eu, ZnS: Eu, ZnS: Mn, ZnCdS: Cu, ZnCdS: Ag, Al, ZnCdS: Cu, Al, (Mg, Ca, Sr, Ba) Ga ₂ S ₄ : Eu and the like.
(vii) Examples of the alkaline earth thiogallate include MGa ₂ S ₄ : Eu (M is as defined above).
Examples of the germanate include 3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn, Zn ₂ GeO ₄ : Mn, and the like.

Examples of the rare earth silicate include Y ₂ SiO ₅ : Ce, Y ₂ SiO ₅ : Tb, and the like.
It does not specifically limit as an organic and an organic complex, You may use any well-known thing. For _{example, Mg 6 As 2 O 11:} Mn , etc. are exemplified. Preferably, it is mainly activated with a lanthanoid element such as Eu, but optionally, instead of or in addition to Eu, the above-mentioned rare earth elements and Cu, Ag, Au, Cr, Co, Ni, Ti and Mn You may use at least 1 sort (s) selected from the group which consists of.

  For example, as shown in the following table, the phosphors can be used alone or in combination to obtain an emission color having a desired color temperature and high color reproducibility.

  Examples of the binder include inorganic substances such as inorganic glass, yttria sol, alumina sol, and silica sol; polyolefin resin, polycarbonate resin, polystyrene resin, epoxy resin, acrylic resin, acrylate resin, methacrylic resin (PMMA, etc.), polyimide resin , Fluororesin, silicone resin (eg, dimethylsiloxane, methylpolysiloxane, etc.), modified silicone resin, one or more resins such as modified epoxy resin; metal alkoxide, metal diketonate, metal diketonate complex, carboxylic acid Examples thereof include a translucent material formed by a sol-gel method using an organometallic compound such as a metal salt as a starting material; and an organic substance such as a liquid crystal polymer. When the light conversion member is composed of a fluorescent substance or the like and a binder, the fluorescent substance or the like and the binder are preferably used in a weight ratio range of about 0.1 to 10: 1.

  Examples of inorganic members include silica, quartz, titanium oxide, tin oxide, zinc oxide, tin monoxide, calcium oxide, magnesium oxide, beryllium oxide, aluminum oxide, silicon nitride, aluminum nitride, SiC, calcium carbonate, potassium carbonate, Examples thereof include barium carbonate, aluminum hydroxide, magnesium hydroxide, aluminum borate, barium titanate, calcium phosphate, calcium silicate, clay, barium sulfate, white clay, inorganic balloon, talc, zeolite, halloysite, and metal pieces (silver powder, etc.). The inorganic member can be contained, for example, at 0.1 to 80% by weight of the total amount of the light conversion member.

  The light conversion member may be, for example, the above-described fluorescent material or the like, optionally mixed with an inorganic member in a binder, and if necessary, using a suitable solvent, potting method, spray method, screen printing method, injection It can be formed into a desired shape by a mold method, a compression method, a transfer method, an injection method, an extrusion method, a lamination method, a calendar method, a vacuum coating method, a powder spray coating method, an electrostatic deposition method, or the like. Moreover, you may utilize the method, electrodeposition, etc. which mix with a fluorescent substance etc. with an inorganic member and a suitable solvent arbitrarily, and shape | mold by pressurizing, heating arbitrarily.

The semiconductor light emitting device of the present invention is preferably sealed with a sealing member. Thereby, a semiconductor element etc. can be protected from the external force, dust, moisture, etc. from an external environment. Further, by appropriately adjusting the shape, it is possible to impart and control the directivity characteristics of light emitted from the light emitting element, for example, the lens effect. The shape of the sealing member may be various shapes such as an elliptical shape, a cube, and a triangular prism as seen from the light emission observation surface side, such as a convex lens shape, a dome shape, or a concave lens shape. As the sealing member, the same material as the above-described binder and inorganic member can be used. In addition, various colorants, fluorescent substances, and the like may be added in order to obtain a filter effect that cuts unnecessary wavelengths from extraneous light and light emitting elements.
Hereinafter, a semiconductor light emitting device of the present invention will be described in detail with reference to the drawings.

Example 1
The semiconductor light emitting device of this example is shown in FIG.
In this semiconductor light emitting device 1, a buffer layer (not shown) made of Al _0.1 Ga _0.9 N and a non-doped GaN layer (not shown) are stacked on a sapphire substrate 2, and an n-type semiconductor layer 3 is formed thereon. A n-side contact layer made of Si-doped GaN, a superlattice n-type cladding layer in which a GaN layer (40Å) and an InGaN layer (20 積 層) are alternately stacked 10 times, and further, a GaN layer As the light-emitting layer 4 and the p-type semiconductor layer 5 having a multiple quantum well structure in which (250Å) and InGaN layers (30Å) are alternately stacked three to six times, an Mg-doped Al _0.1 Ga _0.9 N layer (40Å) and an Mg-doped layer A superlattice p-type cladding layer in which InGaN layers (20Å) are alternately stacked 10 times and a p-side contact layer made of Mg-doped GaN are stacked in this order.

  In a partial region of the n-type semiconductor layer 3, the light emitting layer 4 and the p-type semiconductor layer 5 stacked thereon are removed, and further, a part of the n-type semiconductor layer 3 itself in the thickness direction is removed. An n-electrode 9 is formed on the exposed n-type semiconductor layer 3.

  On the p-type semiconductor layer 5, a first metal film 6 made of an Ag film having a thickness of 1000 と and a Pt film having a thickness of 1000 及 ぶ completely covering the first metal film 6 and partially covering the p-type semiconductor layer 5 are formed. A p-electrode made of the second metal film 7 made of is formed. The first metal film 6 is formed in the end region (FIG. 1A and FIG. 1B, region a) facing the n electrode 9 and the end region not facing the n electrode 9 (FIGS. 1A and 1B). In b), the edge part is arrange | positioned inside rather than area | region b). Furthermore, the distance between the second metal film 7 and the upper surface of the p-type semiconductor layer 5 is longer in the region a than in the region b.

That is, in FIGS. 1A and 1B, the distance La from the end of the first metal film 6 to the end of the second metal film 7 in the second electrode end region a facing the first electrode is 10 μm, The distance Lb from the end of the first metal film 6 to the end of the second metal film 7 in the second electrode end region b that does not face one electrode is 5 μm, and La> Lb.
Further, the distance Ma from the end of the first metal film 6 to the end of the second conductive semiconductor layer 5 in the second electrode end region a facing the first electrode is 15 μm, and the second electrode end not facing the first electrode The distance Mb from the end of the first metal film 6 to the end of the second conductive semiconductor layer 5 in the partial region b is 10 μm, and Ma> Mb.

Such a semiconductor light emitting device can be formed by the following manufacturing method.
<Formation of semiconductor layer>
On a sapphire substrate 2 having a diameter of 2 inches, using a MOVPE reactor, a buffer layer made of Al _0.1 Ga _0.9 N is made 100 μm, a non-doped GaN layer is 1.5 μm, and an n-type semiconductor layer 3 is made of n doped Si-doped GaN. A side contact layer of 2.165 μm, a superlattice n-type cladding layer in which a GaN layer (40 cm) and an InGaN layer (20 cm) are alternately stacked 10 times, a 640 mm, a GaN layer (250 mm) and an InGaN layer (30 mm) As the light emitting layer 4 and the p-type semiconductor layer 5 having a multiple quantum well structure in which 3 to 6 layers are alternately stacked, an Mg-doped Al _0.1 Ga _0.9 N layer (40Å) and an Mg-doped InGaN layer (20Å) are alternately 10 A wafer is fabricated by growing a p-type cladding layer of a superlattice layered twice and a thickness of 0.2 μm and a p-side contact layer made of Mg-doped GaN in this order in a thickness of 0.5 μm. It was.

<Etching>
The obtained wafer was annealed in a reaction vessel at 600 ° C. in a nitrogen atmosphere to further reduce the resistance of the p-type cladding layer and the p-side contact layer.
After annealing, the wafer was taken out from the reaction vessel, a mask having a predetermined shape was formed on the surface of the uppermost p-side contact layer, and etching was performed from above the mask with an etching apparatus to expose a part of the n-side contact layer. .

<Formation of electrode>
After removing the mask, the wafer was placed in the sputtering apparatus, and the Ag target was placed in the sputtering apparatus. Using a sputtering apparatus, an argon gas was used as a sputtering gas, and an Ag film having a thickness of 1000 mm was formed on almost the entire surface of the p-side contact layer of the wafer.
The obtained Ag film is patterned into a predetermined shape using a resist, and further, a Pt film is formed thereon with a thickness of 1000 mm so as to cover the Ag film using a Pt target. 8 was formed.
Next, heat treatment was performed at a temperature not higher than the temperature at which Ag and Pt were not mixed without affecting the element characteristics of the semiconductor layer such as the p-side contact layer by an annealing apparatus. On the exposed n-side contact layer, an n electrode 9 made of Al / Pt / Au was formed to a thickness of 7000 mm.

<Formation of insulating film>
A mask having a predetermined pattern is formed with a resist on the p-side contact layer and the n-side contact layer including the n-electrode 9 and the p-electrode 8, and a SiN film (not shown) is formed thereon with a film thickness of 6000 mm. And the insulating film which coat | covers a part of n electrode 9 and p electrode 8 was formed by the lift-off method.

<Formation of pad electrode>
A mask having a predetermined pattern is formed on the insulating film, the n-electrode 9 and the p-electrode 8 with a resist, and a W layer, a Pt layer and an Au layer are stacked in this order on the insulating film, the n-electrode 9 and the p-electrode 8. A pad electrode (not shown) was formed with a total film thickness of 1 μm.
A semiconductor light emitting device 1 was obtained by dividing the obtained wafer at predetermined locations.

  The semiconductor light-emitting device formed as described above was energized in an atmosphere of temperature 85 ° C. and humidity 85% under the condition of If = 20 mA. Even after continuous energization for 7000 hours, SEM observation on the cross section showed that Ag No generation of leakage current was observed even in the region a where the electric field strength was strong.

For comparison, a light-emitting element similar to the semiconductor light-emitting element described above was formed except that La and Lb were the same length as 5 μm and Ma and Mb were the same length as 10 μm.
In this semiconductor light emitting device, when current was passed in an atmosphere of temperature 85 ° C. and humidity 85% under the condition of If = 20 mA, a leak current was intermittently generated, and the lifetime of this device was 1000 hours or less.
Further, SEM observation in the cross section confirmed that Ag was precipitated on the n-side contact layer side.

Example 2
In the semiconductor light emitting device of this example, instead of the silver electrode in Example 1, a laminated film of Pt (top) / Ni (medium) / Ag (bottom) was formed at 1000 Å / 1000 Å / 1000 、, A semiconductor light emitting device having the same configuration as the semiconductor light emitting device of Example 1 was obtained except that the annealing temperature after the formation of the n electrode 9 was increased to about 600 ° C.
In the obtained semiconductor light emitting device, when energized under the same conditions as in Example 1, even after continuous energization for 10,000 hours, ohmic property is good, no migration occurs, and high quality and reliable semiconductor light emission. An element was obtained.
Furthermore, before and after energization, the Ag electrode was good in that crystal grains of about 10 to 100 nm were observed near the interface with the p-side contact layer, and the ohmic characteristics did not change.
In addition, since the upper surface of the Ag electrode is covered with Ni that does not react with Ag, alloying of Ag and Ni can be avoided, and Ag is disposed at a high density directly on the nitride semiconductor layer. Therefore, the reflection efficiency is good, and the light extraction efficiency is further improved.

Example 3
As the semiconductor light emitting device of this example, semiconductor light emitting devices having substantially the same configuration as in Example 1 were obtained except that the insulating film 10 in Example 2 was replaced with TiN or SiON instead of SiN.
Although the obtained semiconductor light emitting device depends on the operating environment, for example, in the case where the humidity is relatively low, the ohmic property is good, no migration occurs, and the reflection efficiency is the same as in Example 2. Thus, a high-quality and highly reliable semiconductor light-emitting device could be obtained.

Example 4
A plurality of similar semiconductor light emitting elements were formed in the same manner as in Example 1 except that the sizes of the p-type semiconductor layer 5, the first metal film 6 and the second metal film 7 were changed.
That is, as shown in FIG. 2A, an element having Ma of 15 μm, La of 10 μm, and the shortest distance between the first metal film 6 and the n-electrode 9 of 15 μm was formed.
Further, as shown in FIG. 2B, the shortest distance between the first metal film 6 and the n-electrode 9 is the same as that of the semiconductor light emitting device of FIG. 2A, and an element having Ma of 15 μm and La of 5 μm is used. Formed.
Further, as shown in FIG. 2 (c), the shortest distance between the first metal film 6 and the n-electrode 9 is the same as that of the semiconductor light emitting device of FIG. 2 (a), and an element having Ma of 10 μm and La of 5 μm. Formed.

  The obtained device was energized under the same conditions, and the occurrence of leakage current and migration of Ag were evaluated. As a result, in the element of FIG. 2A in which the distance between the p-electrode (strictly, the second metal film 7) and the n-electrode 9 is the shortest, generation of leakage current and occurrence of Ag migration were not observed. This is because the second metal film 7 is in contact with the p-type semiconductor layer 5 with good adhesion to prevent the surface of the p-type semiconductor layer from coming into contact with the atmosphere. This is considered to be because Ag migration can be effectively prevented even in a region where the electric field strength is considered to be increased by energization.

On the other hand, in the device shown in FIGS. 2B and 2C where the distance between the second metal film 7 and the n-electrode is longer than that in the device shown in FIG. 2A, the occurrence of leakage current and the occurrence of Ag migration are recognized. It was.
Moreover, even if the distance between the second metal film 7 and the n electrode is the same as in FIGS. 2B and 2C, the second metal film 7 as shown in FIG. 2B. Between the n electrode and the n electrode, the electric field strength due to energization can be alleviated by arranging both of them with a longer distance from the end of the second metal film 7 to the end of the p-type semiconductor layer. Therefore, it was confirmed that the leakage current and the migration of Ag can be more effectively prevented.

Example 5
As shown in FIGS. 5A and 5B, the semiconductor light emitting device 22 of this example has a buffer layer 12, a non-doped GaN layer 13, and an n side on the sapphire substrate 11 as in Example 1. A contact layer 14, an n-type cladding layer 15, an active layer 16 having a multiple quantum well structure, a p-type cladding layer 17, and a p-side contact layer 18 are laminated in this order. , An Ag film 22 is formed, and a Pt (upper) / Ni (lower) film is stacked thereon as the second metal film 21 to form a p-electrode. An n electrode 19 is formed on the exposed region.

Further, in this semiconductor light emitting device 22, the p-type semiconductor layer and the active layer 16 are removed, and the n-side contact layer 18 is exposed, in the outer edge region of the semiconductor light emitting device 22 where the n electrode 19 is not formed. A plurality of frustoconical convex portions 20 having substantially the same height as the active layer 16 and the p-type semiconductor layer are formed.
The size of the convex portion 20 is about 20 μm ² near the base thereof, the total number of the convex portions is about 800, and the area occupied by the convex portion 20 in one light emitting element is about 16%.
It has been found that by forming such a convex portion, Φv is improved by about 10% compared to an element having no convex portion.

Example 6
In this example, as shown in FIG. 6, the light emitting device was formed by flip-chip mounting the semiconductor light emitting element 1 shown in Example 1 on the mounting substrate 201.

This light emitting device is configured by mounting the LED chip 1 mounted on the submount substrate 205 via the adhesive layer 204 in the recess 202 of the package 212 including the mounting base 201 to which the leads 203 are fixed. The side surface of the concave portion 202 functions as the reflecting portion 206, and the mounting substrate 201 functions as a heat radiating portion and is connected to an external heat radiator (not shown). In addition, a terrace portion 207 is formed on the mounting base 201 outside the recess 202, and a protective element (not shown) is mounted thereon. An opening is formed as a light extraction portion 208 above the recess 202 of the mounting substrate 201, and a light-transmitting sealing member 209 is embedded and sealed in this opening.
With such a configuration, light can be reflected with high efficiency by the Ag film of the p electrode, and the light extraction efficiency from the substrate side of the semiconductor light emitting element can be further improved.

Example 7
In this embodiment, as shown in FIG. 7, the light-emitting device is formed by flip-chip mounting the semiconductor light-emitting element 1 shown in Embodiment 1 into the recess 120a of the stem 120 via the submount member 160. did.

  In the stem 120, the first lead 121 and the second lead 122 are integrally formed of resin, and part of the end portions of the first lead 121 and the second lead 122 are within the recess 120 a of the stem. Exposed. A submount member 160 is placed on the exposed second lead 122. The LED chip 200 is placed on the submount member 160 and in the approximate center of the recess 120a. The electrode 161 provided on the submount member 160 is electrically connected to the first lead 121 via a wire, and the electrode 162 is electrically connected to the second lead 122 via a wire. Yes.

A sealing member 131 including a phosphor 150 is embedded in the recess 120a of the stem, and further, the sealing member 141 covers a part of the sealing member 131 and the stem 120 thereon.
In this light-emitting device, the semiconductor light-emitting element 1 is directly mounted on a lead without using a submount member, and is bonded and electrically connected through a lead-free solder bump using an ultrasonic vibration device. Also good.
With such a configuration, light can be reflected with high efficiency by the Ag film of the p electrode, and the light extraction efficiency from the substrate side of the semiconductor light emitting element can be further improved.

Example 8
In the semiconductor light emitting device 30 of this embodiment, as shown in FIG. 8A, the n-type semiconductor layer is thinned from the end portion 31 where the n pad electrode is formed toward the center of the light emitting device by etching. The constricted portion 32 is exposed, and is exposed in a shape having an extending portion 33 so as to connect a pair of constricted portions 32 facing each other. A p-type semiconductor layer is formed in a region sandwiching the extending portion 33.
Except for these configurations, the laminated structure is substantially the same as in Example 2.

  As shown in FIG. 8B, a Pt (upper) / Ni (middle) / Ag (lower) laminated film is formed on the p-type semiconductor layer formed in the region sandwiching the extending portion 33. A Pt (upper) / Au (lower) film is formed as the second metal film 34, and further on the n-type semiconductor layer from the end 31 to the constricted part 32 and the extended part 33. An n-electrode 35 is formed. Also, pad electrodes 36 and 37 are formed on the second metal film 34 and the n-electrode 35, respectively. The pad electrodes 36 and 37 can be formed of the same material at the same time, thereby reducing the number of manufacturing steps for forming the electrodes.

  The semiconductor light emitting element 30 configured as described above is formed on an aluminum nitride plate by plating, for example, as shown in FIGS. 9A and 9B which are XX cross-sectional views in FIG. Two light-emitting devices 43 are formed by flip-chip bonding to a support substrate 42 on which conductor wirings 40 and 41 made of Au are formed in parallel connection via p and n pad electrodes and bump electrodes (FIG. 9). (C)).

The conductor wirings 40 and 41 are formed in a comb shape so as to be insulated and separated from each other as a pair of positive and negative electrodes.
From the area connected to the positive electrode side of the positive (+) pole side conductor wiring 40 and the external electrode (not shown) arranged on the support substrate 42, the position is opposed to the p pad electrode of one light emitting element. Extending to a position facing the p-pad electrode of the other light emitting element. Similarly, the negative (−) pole side conductor wiring 41 disposed on the support substrate 42 is connected to an external electrode (not shown) from a region facing one n-pad electrode of one light-emitting element and the other light-emitting element. Extending to a region facing the other n pad electrode of one light emitting element via a region connected to the negative electrode side of the light emitting element and a region facing the other n pad electrode of the other light emitting element. In addition, when viewed from the direction perpendicular to the support substrate 42, the outer edge of the negative-side conductor wiring 41 has a number of arcuate shapes protruding in the direction of the positive-side conductor wiring 40, while the positive-side conductor The outer edge portion of the wiring 40 has a concave shape corresponding to the convex outer edge on the negative electrode side. The area of the light emitting element 30 facing the p pad electrode 36 is larger than the area facing the n pad electrode 37, and the number of p pad electrodes 36 is set larger than the number of n pad electrodes 37.

  By mounting two semiconductor light emitting elements 30 on such a support substrate 42 in parallel connection, the conductor wiring is simplified as compared with the case of serial connection. In addition, combined with the formation of the conductor wirings 40 and 41 in a comb shape, it is possible to further improve the heat dissipation from the semiconductor light emitting element 30 that is flip-chip mounted.

  Further, in a region other than the region where the semiconductor light emitting element 30 and the support substrate 42 are bonded by the bump electrode 44, a resin layer 39 is disposed between the semiconductor light emitting element 30 and the support substrate 42 with silicone resin. Yes. The silicone resin can be formed by screen printing on the surface of the support substrate 42. And the through-hole is provided in the bump electrode 44 formation area | region of the resin layer 39 by a silicone resin, and the surface of the conductor wiring 40 and 41 is exposed. The inner wall of the through hole in the resin layer 39 has a tapered shape. With such a shape, the connection with the bump electrode 44 can be easily performed.

The bump electrode 44 is made of Au, and includes 24 bumps for bonding the p-pad electrode 36 and 12 bumps for bonding the n-pad electrode 37. The maximum diameter is about 1 × 2 mm for the light-emitting element. Bonding is set to a size of 105 μm and a maximum height of about 40 μm.
Bonding by bumps is performed by applying ultrasonic waves while applying pressure from the substrate side of the light emitting element so that the positive and negative electrodes of the light emitting element face each other directly above the bump. By applying, both the positive and negative electrodes of the light emitting element and the conductor wiring are joined via the bump. At this time, since the silicone resin is soft and rich in elasticity, it shrinks due to pressure, and often enters the gaps on the electrode surface of the LED chip. In addition, the number of bumps in the through hole is adjusted in advance before die bonding so that the bonding force between the electrode of the light emitting element and the conductor wiring is sufficiently larger than the elastic force of the silicone resin compressed by die bonding. deep. In this way, the light emitting element is not pushed back in the direction opposite to the support substrate due to the elastic force of the silicone resin, the strength of bonding between the electrode of the light emitting element and the conductor wiring is kept constant, and Since conduction between the electrode and the conductor wiring is not interrupted, a highly reliable light-emitting device can be obtained.

  The support substrate is cut so as to include a desired number of light emitting elements in FIG. 9, mounted on a package, connected to an external electrode through a conductive wire, and becomes a light emitting device. The shape of the support substrate after cutting may be any shape other than a rectangle.

By adopting such a configuration, in the light-emitting element in which heat is likely to be trapped, the inner heat can be dissipated by a relatively large number of bumps mounted and wide conductor wiring, A light emitting device with improved heat dissipation, high luminance light emission, and high reliability can be obtained.
In addition, the presence of the resin layer can substantially eliminate the gap between the semiconductor light emitting element and the support substrate, and prevents the complicated light refraction caused by the air present in the gap, thereby improving the light extraction efficiency. In addition, the heat conduction can be promoted by the resin layer, and the heat dissipation effect can be improved.

  Moreover, with such a configuration, light from the light emitting element can be reflected with high efficiency by the lowermost Ag film constituting the p-electrode, and light extraction from the sapphire substrate side in the flip chip mounted light emitting element is possible. Efficiency can be further improved.

Example 9
The light-emitting device in this example is substantially the same as Example 7 except that a silicone resin containing aluminum oxide is used as a filler, squeezing to the height of the bump or more, screen printing, and forming a resin layer. It is.
Thereby, the light-emitting device with higher light extraction efficiency and higher heat dissipation effect can be obtained.

Example 10
In the light emitting device 45 of this embodiment, as shown in FIG. 10, a translucent resin layer 39a is embedded in a gap formed between the light emitting element 30 and the light emitting element 30 which are flip-chip mounted. Further, the light emitting surface side of these light emitting elements 30 and the upper surface of the resin layer 39a contain a phosphor that absorbs at least a part of the light from the light emitting elements 30 and emits light having a different wavelength. Except for the fact that the wavelength conversion member 47 is formed, it is substantially the same as the light emitting device of Example 7.
The phosphor may be contained not only in the wavelength conversion member 47 but also in both the resin layers 39 and 39a, or may be contained only in one or both of the resin layers 39 and 39a. .
As described above, the resin layer 39a covers at least the side surface of the light emitting element, whereby the wavelength conversion member 47 can be prevented from entering the side surface side of the light emitting element 30 in the formation process.

Example 11
In this embodiment, as shown in FIG. 11, the LED chip 200 is mounted face-up on the mounting base 201 to form a light emitting device.
In this light emitting device, an LED chip 200 is fixed to a recess 202 of a package 212 including a mounting base 201 insulated from a lead 203 via an adhesive layer 204. The concave portion 202 has a shape (tapered shape) whose side surface functions as the reflective portion 206 and becomes wider in the opening direction. With such a shape, light emitted from the LED chip 200 is reflected on the side surface of the recess 202 and travels toward the front of the package, so that light extraction efficiency can be improved. The mounting substrate 201 is made of, for example, glass epoxy resin or ceramic. The adhesive layer 204 is a thermosetting resin such as an epoxy resin, for example. The mounting substrate 201 functions as a heat radiating portion and is connected to an external heat radiator (not shown). In this manner, a light emitting device with excellent thermal design can be obtained with a configuration that separates the mounting base 201 and the leads 203 and can ensure heat dissipation.

Further, a light-transmitting sealing member 209 is embedded in and above the concave portion 202 of the mounting substrate 201, and further formed into an optical lens shape. By providing the optical system (lens), light emission with desired directivity can be obtained.
Further, the electrodes of the LED chip 200 are electrically connected to the leads 203 by wires 210 and extend outside the package.

  The package 212 may be formed integrally with the external electrode, and further divided into a plurality of parts and used in combination by fitting or the like. Such a package 212 can be formed relatively easily by insert molding or the like. When the package material is a metal, even if a light emitting device using an LED chip that emits light including ultraviolet rays is used at a high output, it deteriorates due to ultraviolet rays, yellows, etc. The lifetime of the light emitting device can be improved without causing a decrease.

In addition, although the wire 210 is not specifically limited, For example, metals, such as gold | metal | money, copper, platinum, aluminum, and those alloys are used, and it is a diameter of about 10-70 micrometers.
Further, the sealing member 209 protects the LED chip 200, the wire 210, and optionally the coating layer containing the phosphor from the outside, or improves the light extraction efficiency, depending on the use application of the light emitting device. Provided. The sealing member 209 can relax the directivity from the LED chip 200 by adding a diffusing agent to the mold member, and can also increase the viewing angle.

  In this embodiment and any of the above-described embodiments, a concave portion is provided in a metal base, a light emitting element is mounted, and the lead is insulated and separated from the base and hermetically sealed. The LED chip may be directly mounted on the concave portion on the metal substrate like COB. In addition, a single mounting substrate or a single recess in which a plurality of elements are integrated and mounted, or a plurality of light-emitting elements mounted on a substrate may be provided.

  The semiconductor light emitting device of the present invention can be suitably used for a semiconductor light emitting device constituting various light sources such as a backlight light source, a display, illumination, and a vehicle lamp.

It is sectional drawing and the top view which show embodiment of the semiconductor light-emitting device in this invention. It is sectional drawing which shows another embodiment of the semiconductor light-emitting device of this invention. It is a top view for demonstrating the planar shape of the semiconductor layer in the semiconductor light-emitting device of this invention. It is a top view for demonstrating the planar shape of another semiconductor layer in the semiconductor light-emitting device of this invention. It is the top view (a) and partial sectional view (b) which show another embodiment of the semiconductor light-emitting device in this invention. It is sectional drawing which shows the light-emitting device which mounted the semiconductor light-emitting device in this invention. It is sectional drawing which shows another light-emitting device which mounted the semiconductor light-emitting device in this invention. It is the top view (a) which shows arrangement | positioning of the electrode in the semiconductor light-emitting device in this invention, and the top view (b) which shows arrangement | positioning of a pad electrode. It is the top view (a) of the support substrate for mounting the semiconductor light emitting element in this invention, the circuit diagram (b) of the mounted light-emitting device, and sectional drawing (c) which shows a light-emitting device. It is sectional drawing which shows the light-emitting device which mounted the semiconductor light-emitting device in this invention. It is sectional drawing which shows the light-emitting device which mounted the semiconductor light-emitting device in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 30 Semiconductor light-emitting device 2, 11 Sapphire substrate 3 N-type semiconductor layer 4 Light-emitting layer 5 P-type semiconductor layer 6 1st metal film 7, 21, 34 2nd metal film 8 P electrode (electrode)
9, 19, 35 n-electrode 10 insulating film 12 buffer layer 13 non-doped GaN layer 14 n-side contact layer 15 n-type cladding layer 16 active layer 17 p-type cladding layer 18 p-side contact layer 20 convex portion 22 Ag film

31 End portion 32 Constriction portion 33 Extension portion 36, 37 Pad electrode 38 p Pad electrode 39, 39a Resin layer 40, 41 Conductor wiring 42 Support substrate 43, 45 Light emitting device 44 Bump electrode 47 Wavelength conversion member 120 Stem 120a Recess 121 First Lead 122 second lead 131, 141 sealing member 150 phosphor 160 submount member 161, 162 electrode

200 LED chip 201 Mounting base 202 Recess 203 Lead 204 Adhesive layer 205 Submount substrate 206 Reflection portion 207 Terrace portion 208 Light extraction portion 209 Sealing member 210 Wire 211 Inner surface 212 Package a First region b Second region N First conductivity Type semiconductor layer P second conductivity type semiconductor layer E first electrodes La, Lb distance Ma, Mb from the first metal film end to the second metal film end to the second conductivity type semiconductor layer end Distance to the part

Claims (7)

A first electrode having at least a first conductivity type semiconductor layer and a second conductivity type semiconductor layer, connected to the first conductivity type semiconductor layer, and a second electrode connected to the second conductivity type semiconductor layer And the first electrode and the second electrode are arranged on the same surface side of the first conductivity type semiconductor layer,
The second electrode includes a first metal film containing silver or a silver alloy, a second metal film that covers the first metal film and is made of a metal different from silver, and faces the first electrode. a first region, a second region which is a region other than the first region, and whether one prior Symbol ends of the first metal layer in at least a portion of the first region and the end portion of the second metal film The semiconductor element is provided so that the distance is larger than the distance in the second region. A first electrode having at least a first conductivity type semiconductor layer and a second conductivity type semiconductor layer, connected to the first conductivity type semiconductor layer, and a second electrode connected to the second conductivity type semiconductor layer And the first electrode and the second electrode are arranged on the same surface side of the first conductivity type semiconductor layer,
The second electrode includes a first metal film containing silver or a silver alloy, and a second metal film that covers the first metal film and is made of a metal different from silver,
The second metal film is disposed so as to cover a part of the second conductive semiconductor layer exposed from the first metal film, and covers the second conductive semiconductor layer in a region facing the first electrode. A width of the semiconductor element is larger than the width in a region facing the edge of the semiconductor element.   A second metal film is disposed in contact with the second conductive semiconductor layer exposed from the first metal film, and a contact resistance with the second conductive semiconductor layer is greater than a contact resistance with the first metal film. The semiconductor device according to claim 1.   The semiconductor device according to claim 1, wherein the first conductive semiconductor layer and the second conductive semiconductor layer are nitride semiconductor layers.   Furthermore, the semiconductor element as described in any one of Claims 1-4 which has the insulating film which consists of nitride which coat | covers at least one part of a 2nd metal film.   The first metal film is formed of a laminated film of at least a film made of silver or a silver alloy and a metal film that does not substantially react with silver disposed on the film. The semiconductor element as described in one.   The distance Ma from the first metal film end to the second conductivity type semiconductor layer end in the first region or the region facing the first electrode, and the edge of the second region or the semiconductor element The semiconductor element according to claim 1, wherein a distance Mb from an end of the first metal film to an end of the second conductivity type semiconductor layer in a region to be satisfied satisfies Ma> Mb.

Images