JP2002324915A - Integrated nitride semiconductor light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an integrated nitride semiconductor light emitting device which has a large area and has high light emitting efficiency. SOLUTION: A plurality of light emitting devices are arranged in parallel with each other on a single substrate, and a semiconductor layer comprises a rectangular n layer formed by the separation of an n type gallium nitride compound semiconductor layer by separation recesses, a light emitting layer, and a p layer. One long side and two short sides of the n layer are located close to one long side and two short sides of the light emitting layer and the p layers, respectively. Between the other long side of the n layer and the other long side of the p layer, an n-side ohmic electrode having essentially the same length as the long sides of the p layer is provided on the n layer, a p-side ohmic electrode is provided over nearly the entire surface of the p layer, and a p pad electrode is provided along one long side of the p layer on the p-side ohmic electrode. The distance between one long side of the p layer and the n-side ohmic electrode is set to 250 μm or below. Out of the light emitting devices, at least some of them have, on the most upper surface of the semiconductor layer, a fluorescent material which absorbs part of the light from the light emitting layer and can emit light of different wavelengths.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a large-area color conversion type nitride semiconductor light emitting device.

[0002]

2. Description of the Related Art In recent years, a white light emitting light source has been developed and used by using a light emitting element formed using a gallium nitride compound semiconductor.

For example, three types of light emitting diodes capable of emitting red, green and blue light, respectively, are mounted, and white light can be obtained by mixing these colors.

[0004]

However, when these light emitting elements are formed using different materials, the driving power of each light emitting element is different and it is necessary to apply a predetermined voltage individually. The circuit becomes complicated. In addition, since the light-emitting elements are semiconductor light-emitting elements, temperature characteristics and changes with time are individually different, and the color tone changes depending on the use environment. Furthermore, it is extremely difficult to uniformly mix the light generated by each light emitting element, and color unevenness may occur. In addition, there is a limit in arranging the elements close to each other in order to suppress color unevenness due to a difference in arrangement accuracy of each element and color unevenness, and it has been difficult to obtain good optical characteristics.

Therefore, in recent years, a light-emitting light source (white light-emitting diode) capable of emitting white light, which is a combination of a light-emitting element chip composed of a gallium nitride-based compound semiconductor and a phosphor, has been developed and used. This white light-emitting diode is, for example, a light-emitting element chip that emits blue light and a phosphor that can absorb a part of the blue light and convert the wavelength, and the wavelength is converted by the blue light and the phosphor. The white light is emitted by mixing the light with the light.

However, at the present time when a light-emitting element for illumination is required, a light-emitting element having a small light-emitting area and a wider light-emitting area is required for the above-mentioned white light-emitting diode.

Accordingly, the present invention solves the above-mentioned problems, and provides an integrated nitride semiconductor light emitting device which emits light uniformly in a large area and has excellent color mixing.

[0008]

To achieve the above object, an integrated nitride semiconductor light emitting device according to the present invention has a plurality of light emitting devices juxtaposed on the same substrate. Each of the light emitting elements has a semiconductor layer made of the same material. The semiconductor layer includes a rectangular n layer formed by separating an n-type gallium nitride based compound semiconductor layer formed on a substrate by a separation groove, and a gallium nitride layer. An integrated nitride semiconductor light emitting device comprising a light emitting layer made of a compound semiconductor layer and a p layer made of a p-type gallium nitride compound semiconductor, wherein one long side of the n layer and two short sides The sides are one long side of the light emitting layer and the p layer, respectively.
One of the short sides, and has substantially the same length as the long side of the p-layer on the n-layer between the other long side of the n-layer and the other long side of the p-layer. an n-side ohmic electrode, a p-side ohmic electrode on substantially the entire surface of the p-layer, a p-pad electrode on the p-side ohmic electrode along one long side of the p-layer, and one of the p-layers. The long side and the n
The distance from the side ohmic electrode is 250 μm or less, and at least some of the plurality of light emitting elements absorb at least a part of light emitted from the light emitting layer on the uppermost surface of the semiconductor layer. And a phosphor capable of emitting different wavelengths.

The integrated nitride semiconductor light-emitting device according to the present invention having the above-described structure has excellent reliability, and can emit light with high luminance and uniformity over a large area.
In the integrated nitride semiconductor light emitting device according to the present invention,
Each light emitting element can be made sufficiently long in one direction (longitudinal direction) without deteriorating the uniformity of light emission and the light emission efficiency, so that the light emission area can be increased and the light emission efficiency can be increased.

Further, in the integrated nitride semiconductor light emitting device according to the present invention, in order to enable more uniform light emission in each light emitting device and to increase the light emitting efficiency, one long side of the p layer and the n 220μ spacing from the side ohmic electrode
m is more preferably set to m or less.

According to a second aspect of the present invention, there is provided an integrated nitride semiconductor device, wherein three light emitting elements are arranged in a set on the same substrate, and pixels of three different colors can be obtained from the one set. I do.

As a result, a light emitting device having excellent color rendering properties can be obtained. Further, by adjusting the types and amounts of the phosphors arranged in the respective light emitting elements, light of any intermediate color can be easily obtained.

Further, in the integrated nitride semiconductor light emitting device of the present invention, the distance between one long side of the p layer of one light emitting element and the other long side of the p layer of another adjacent light emitting element is 50.
μm to 150 μm, more preferably 50 μm to 1 μm.
00 μm. As described above, in the integrated nitride semiconductor light emitting device of the present invention, the light emitting surfaces of the respective light emitting devices are remarkably close to each other as compared with the case where the devices emitting different lights are arranged in an array. In addition, since the arrangement accuracy of each of the light emitting elements is equal, good directivity and color mixing can be obtained.

If the pixels of the light emitting elements are red, blue, and green, respectively, white light with excellent color rendering properties can be obtained by mixing the three primary colors.

In the integrated nitride semiconductor light-emitting device according to the present invention, if the light-emitting layer is configured to emit blue light, the desired various types of phosphors can be obtained simply by adjusting the type and amount of the phosphor. Intermediate colors can be easily obtained.

In the integrated nitride semiconductor light-emitting device according to the present invention, when the light-emitting layer is configured to emit light in the ultraviolet region, only light emission from the phosphor is observed, thereby preventing color unevenness. be able to.

The integrated nitride semiconductor light emitting device according to the present invention may be configured such that the plurality of light emitting devices are connected in series. With this configuration, the light emitted from the element end face is reflected by the connection electrode formed to connect in series, and is extracted in the upper surface direction. This makes it possible to minimize the distance between each pixel while maintaining high reliability, and when each pixel emits a different color, it is possible to obtain an integrated nitride semiconductor light emitting device having excellent color mixing.

In the integrated nitride semiconductor light emitting device according to the present invention, the plurality of light emitting devices may be connected in parallel. With this configuration, the phosphor can be arranged from the end face of the p-layer to the end face of the n-layer of each element, which is preferable.

[0019]

DETAILED DESCRIPTION OF THE INVENTION The present inventor has considered that color unevenness generated when a color conversion layer is provided on an integrated nitride semiconductor device is caused by color variation between individual devices. Increasing the light emitting area of one element has caused the following problems.

In a nitride semiconductor light emitting device, an n-type gallium nitride-based compound semiconductor layer, a gallium nitride-based compound semiconductor light-emitting layer, and a p-type gallium nitride-based compound semiconductor layer are usually sequentially stacked on a sapphire substrate. An n-side ohmic electrode is formed on the n-type gallium nitride-based compound semiconductor layer where the layer and a part of the light-emitting layer are removed and exposed, and a p-side ohmic electrode is formed on the p-type gallium nitride-based compound semiconductor layer. Be composed.

Here, especially in the nitride semiconductor light emitting device,
Since the resistance of the p-type gallium nitride-based compound semiconductor is relatively high, a current is injected into the entire light emitting layer by forming a p-side ohmic electrode on almost the entire surface of the p-type gallium nitride-based compound semiconductor layer. are doing. In the nitride semiconductor light emitting device, it is necessary to form an n-side electrode on a part of the n-type gallium nitride-based compound semiconductor layer as described above. For this reason, an n-side ohmic electrode is formed at one corner of the n-type gallium nitride-based compound semiconductor layer so that a current is injected into the entire light emitting layer, and a p-side ohmic electrode that is diagonal to the one corner is formed. A p-side pad electrode is formed at another corner of the electrode.

That is, the nitride semiconductor light emitting device is formed using an insulating sapphire substrate, and the p-type gallium nitride based compound semiconductor has a relatively high resistance value. Due to the circumstances different from the light emitting element of the above, the p-side ohmic electrode is provided on almost the entire surface of the p-type gallium nitride based semiconductor layer, and the n-side ohmic electrode and the p-side pad electrode are formed at diagonal positions. Current is injected into the entire light emitting layer.

However, the above configuration (electrode configuration)
Means that one light emitting element chip is, for example, 300 μm × 3
When the size is not more than 00 μm, current can be almost uniformly injected into the light emitting layer.
When the size exceeds μm, the problem that the current injected into the light emitting layer becomes uneven becomes apparent. For this reason, even if a large-area light emitting element is formed by enlarging the above configuration in a similar shape, and a white light emitting diode is formed by combining the large area light emitting element and a phosphor, uniform light emission can be obtained. Did not.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide an integrated nitride semiconductor light emitting device capable of emitting light uniformly over a large area.

Hereinafter, an integrated nitride semiconductor light emitting device according to an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the integrated nitride semiconductor light emitting device of the first embodiment has a thickness of, for example, 1000 μm × 1.
The first rectangular shape on the sapphire substrate 11 of
The light emitting element 1, the second light emitting element 2, and the third light emitting element 3 are arranged in parallel with each other, and the width of each light emitting element is set to a certain value or less. As a result, current flows uniformly through the light emitting layer of each element. By disposing a phosphor on the semiconductor layer side of such a light emitting element, a color conversion light emitting element capable of improving the overall light emitting efficiency and emitting light uniformly over a large area can be obtained.

These components will be described in detail below. Embodiment 1 (Light-Emitting Elements 1, 2, 3) An integrated nitride semiconductor light-emitting element 100 of the present embodiment has a first light-emitting element 1, a second light-emitting element 2, and a third light-emitting element on one and the same substrate. The elements 3 are juxtaposed. These light-emitting elements preferably include a semiconductor light-emitting element having a semiconductor layer made of the same material and having a relatively high band energy capable of efficiently exciting various phosphor substances. As such a semiconductor element, a nitride compound semiconductor formed by an MOCVD method or the like is used. The nitride-based semiconductor is InnAlmGa1-n-mN (where 0 ≦ n,
0 ≦ m, n + m ≦ n) as the light emitting layer. Examples of the semiconductor structure include a homostructure having a MIS junction, a PIN junction, and a pn junction, a heterostructure, and a double heterostructure. Various emission wavelengths can be selected depending on the material of the semiconductor layer and the degree of mixed crystal thereof. Further, a single quantum well structure or a multiple quantum well structure in which the semiconductor light emitting layer is formed as a thin film in which a quantum effect occurs can be used.

In the integrated semiconductor light emitting device of the present invention, when emitting white light, the main emission peak of the light emitting device is 400 nm in consideration of the complementary color relationship with the phosphor and the deterioration of the resin.
530 or less, more preferably 420 nm
Not less than 490 nm. In order to improve the efficiency of the light emitting element and the phosphor, respectively, 450 nm or more and 475 n
It is more preferable to use a light emitting element having a main emission peak at m or less.

On the other hand, it is also possible to use a resin or glass or the like which is relatively resistant to ultraviolet light, and to use a light emitting element which can emit ultraviolet light having a main emission peak in a short wavelength region around 400 nm.

Further, the structure of the integrated nitride semiconductor device of the present invention is an improvement on the specific structure of the gallium nitride-based compound semiconductor based on the following knowledge.

That is, in the light emitting device constituted by using a gallium nitride compound semiconductor, an n-side ohmic electrode is formed on a part of an n-layer and a n-side ohmic electrode is formed on the n-side ohmic electrode in the conventional technique as described above. It has a unique structure in which a p-layer is formed close to the n-layer via a light-emitting layer, and a p-side ohmic electrode is formed on almost the entire surface of the p-layer.

In such a unique configuration, it was found that the current injected into the light emitting layer within a distance of 250 μm from the n-side ohmic electrode was almost constant, but rapidly decreased at a distance of 250 μm or more. Actually, when the distance is more than 220 μm, the current injected into the light emitting layer starts to gradually decrease, but the current value can be regarded as substantially constant up to 250 μm.

This phenomenon (a phenomenon in which the injected current sharply decreases when the light emitting layer is separated by 250 μm or more).
Is considered to be caused by the resistance value of the n-layer, but it has been confirmed that the resistance does not usually change in the range of the resistance value of the n-layer used.

The following can be said from the above findings.

Even when a rectangular light emitting layer and a p-type gallium nitride compound semiconductor layer which are long in one direction are formed on the n-type gallium nitride compound semiconductor layer to increase the light emitting area, the n-side ohmic electrode can be formed. If the distance from is within 250 μm, the current can be injected almost uniformly into the entire light emitting layer.

Specifically, along one long side of the rectangular light emitting layer and the p-type gallium nitride compound semiconductor layer, n having the same length as the light emitting layer and the p-type gallium nitride compound semiconductor layer is formed.
A side ohmic electrode is formed, and the distance between the n-side ohmic electrode and the other long side of the light emitting layer and the p-type gallium nitride based compound semiconductor layer is 250 μm or less, more preferably 22 μm or less.
When the thickness is 0 μm or less, current can be almost uniformly injected into the light emitting layer.

The integrated nitride semiconductor light emitting device according to the first embodiment is configured based on the above-described concept.

More specifically, in the light emitting devices 1, 2, and 3 of the integrated nitride semiconductor light emitting device of the first embodiment,
Each semiconductor layer and each electrode are formed as follows.

(1) The n-type gallium nitride-based compound semiconductor layer 12 (n-layer 12) is formed, for example, by separating the n-type gallium nitride-based compound semiconductor layer grown on almost the entire surface of the substrate 11 made of sapphire by the separation groove 41. It is formed so that it is separated and the planar shape becomes a rectangle.

Here, in the first embodiment, the n-type gallium nitride-based compound semiconductor layer 12 (n-layer 12) preferably has a film thickness 1 formed on the sapphire substrate 11 as shown in FIG. .5 μm undoped GaN layer 121,
2.2-μm thick Si-doped GaN layer 122, thickness 30
00 ° undoped GaN layer 123, 300 ° thick S
i-doped GaN layer 124, undoped Ga with a thickness of 50 °
It has a stacked structure of an N layer 125 and a multilayer film layer 126. By thus forming the n-layer 12 with the above-described laminated structure, the forward voltage Vf can be reduced and the luminous efficiency can be improved. Note that the multilayer film layer 126 is preferably made of a first layer of undoped GaN having a thickness of 40 ° and undoped In0.13G.
It is configured by alternately laminating a second layer of a 0.87N and a thickness of 20 ° so that each of the second layers has 10 layers.

The n-layer 1 of the layered structure of the first embodiment
2 as a whole is substantially determined by the Si-doped GaN layer 122 having a thickness of 2.2 μm, and in the first embodiment, the resistivity of this layer 122 is set to 5.5 to 7.2 ×
It is preferable to set the range of 10 ⁻³ Ωcm and the film thickness to 2.0 μm or more. In this case, current can be more uniformly injected into the entire light emitting layer 10 and more uniform light emission can be obtained.

In the GaN layer, 3 × 10 ^{18 to} 6
By doping Si in the range of × 10 ¹⁸ cm ⁻³ , a Si-doped GaN film having a resistivity in the range of 5.5 to 7.2 × 10 ⁻³ Ωcm can be formed.

(2) The light emitting layer 10 is a rectangle having substantially the same length as the n layer 12 and a width smaller than the n layer 12.
The long side is formed on n layer 12 such that one long side substantially coincides with one long side of n layer 12. By forming in this manner, a region for forming an n-side ohmic electrode on the n-layer 12 along the light-emitting layer 10 is secured.

Here, in the first embodiment, the light emitting layer 10
The distance L1, L2, L3 between the long side located on the side distant from the n-side ohmic electrode and the n-side ohmic electrode is 2
It was set to be 20 μm.

In the first embodiment, the light emitting layer 1
0 is In _x Ga _{1-x in} which part of GaN is replaced by In
It can be composed of N layers. The light emitting layer 10
_{You can} also configure the In x _{Ga 1-x} N layer to include at least one layer. In this case, In _x Ga
_The emission wavelength can be changed by changing the In content in the _1-xN layer.

(3) The n-side ohmic electrode 14 (14)
It has substantially the same length as the light emitting layer 10, and is formed on the n layer 12 along the light emitting layer 10 and in proximity to the light emitting layer 10. Further, the distance between the n-side ohmic electrode 14 and the light emitting layer 10 is set to 10 to 20 μm due to manufacturing restrictions. In the present invention, the distance is preferably set to 10 μm or less. The width over which current can be injected uniformly can be increased.

That is, when the distance between the n-side ohmic electrode 14 and the light-emitting layer 10 is set to 20 μm, the width of the light-emitting layer capable of uniformly injecting the current is 200 μm at maximum, but the width of the light-emitting layer is not more than 200 μm. Space between layer 10 and 5
When the thickness is set to μm, the width of the light emitting layer that can uniformly inject current can be set to 215 μm at the maximum.

The n-side ohmic electrode 14 (14)
In order to improve the ohmic contact with the n-layer 12, it is preferable to use a layer containing W and Al, and more preferably, a W layer (200 °), an Al layer (1000 °), a W layer (500 °), and a Pt layer. (3000 °), Ni layer (60
Å) is formed by sequentially laminating.

(4) P-type gallium nitride based semiconductor layer 13
Has the same planar shape as the light emitting layer 10 and is formed on the light emitting layer 10 so as to overlap.

Actually, the light emitting layer 10 and the p-type gallium nitride based semiconductor layer 13 are formed by superposing the light emitting layer 10 and the p layer 13 on the n layer 12 and then forming the n-side ohmic electrode 14. 12 is formed by etching all at once to expose the surface.

In the first embodiment, the p-type gallium nitride based semiconductor layer 13 is formed to a thickness of 1500 °.

(5) The p-side ohmic electrode 15 is formed on almost the entire surface of the p-type gallium nitride based semiconductor layer 13.
In order to obtain good ohmic contact with the layer 13, it is preferable that the Ni layer and the Pt layer are stacked, and more preferably, the Ni layer and the Pt layer are stacked.
Are laminated.

(6) The p-pad electrode 16 is made of, for example, Pt having a thickness of 3000 、, and on the p-side ohmic electrode 15, the p-side ohmic electrode 15 located on the side away from the n-side ohmic electrode 14. Is formed along the long side of.

In the light emitting device thus configured, since the distance between each electrode is constant at any place, electrons can be uniformly supplied to the entire light emitting layer 10 and one light emitting layer In the above, the light absorptance of the arranged phosphor can be made substantially equal in all the particles. In addition, the light-emitting portion on the semiconductor layer side can be one and can be substantially rectangular. This gives 1
The color mixture of the pixels obtained from each element on one substrate is improved, and an integrated nitride semiconductor light emitting element with less color unevenness is obtained. (Series connection) In the integrated nitride semiconductor light emitting device of the first embodiment, the light emitting devices 1 and
Elements 2 and 3 are separated from each other by an insulating protective film 17 and connected by a connection electrode 21 as follows.

The insulating protective film 17 is formed so as to cover the entire device except on the p pad electrode 16 and the n-side ohmic electrode 14 of each light emitting device.

The connection electrode 21 is formed continuously on the n-side ohmic electrode 14 of the light emitting element 1, on the insulating film 17 formed in the separation groove 41, and on the p-side ohmic electrode 16 of the second light emitting element 2. As a result, the n-side ohmic electrode 14 of the first light emitting element 1 and the p-side ohmic electrode 16 of the second light emitting element 2 are connected.

The connection electrode 21 is similarly formed between the second light emitting element 2 and the third light emitting element 3, whereby the n-side ohmic electrode 14 of the second light emitting element 2 and the third light emitting element 3 The third p-side ohmic electrode 16 is connected.
The connection electrode 21 can be made of various metals such as Pt or Au, but in order to improve the adhesion to the p and n pad electrodes, Ti (for example, 400 °), Pt (for example, 6000 °) , Au (eg, 1000 °), N
i (for example, 60 °) is preferably laminated in order.

In the first embodiment, an external connection electrode 26 made of the same material as that of the connection electrode 21 is further formed on the p pad electrode 16 of the light emitting element 1, and the n
An external connection electrode 24 made of the same material as the connection electrode 21 is formed on the pad electrode 14.

Each of the light emitting devices 1, 2, 3 of the integrated nitride semiconductor light emitting device of the first embodiment configured as described above
An n-side ohmic electrode is formed so as to have a rectangular light emitting layer 10 and to be adjacent along one long side of the light emitting layer 10;
Since the distance L1, L2, L3 between the other long side of the light emitting layer 10 and the n-side ohmic electrode is set to 220 μm,
Light can be supplied substantially uniformly to the entire phosphor disposed on the upper surface of the light emitting layer 10.

With such a configuration, the integrated nitride semiconductor device of the first embodiment is provided with
Since the light can be emitted uniformly over the whole of the light emitting layers 10, the light emitting efficiency of each light emitting element can be increased, and the light emitting efficiency as a whole can be improved.

In the integrated nitride semiconductor device according to the first embodiment, the isolation grooves 4 parallel to each other only in one direction.
1, the respective elements are separated from each other, so that the ratio of the area occupied by the separation grooves 41 to the entire area of the substrate 11 is smaller than that in the conventional example in which the grooves are formed in a lattice shape and the respective elements are separated. Can be reduced.

As a result, the ratio of the area occupied by the light emitting layer 10 to the entire area of the integrated nitride semiconductor element (the total area of the light emitting layers 10 of the light emitting elements 1, 2, 3) can be increased. Efficiency and uniformity of light emission can be improved.

Since the end face of each element is covered with the connection electrode 21, the light emitted from the end face is reflected by the connection electrode and extracted from the light emitting surface side. This allows
Light absorption at the element end face is suppressed, the reliability of the element is improved, and the light from the light emitting element can be efficiently color-converted by the phosphor.

Further, in order to improve the electrostatic withstand voltage characteristics of the device, the Si-doped GaN layer 122 may be formed to have a thickness of 4.2 μm, and the p-layer 13 may have a thickness of 3500 °. (Phosphors 71, 72, 73, 74) In the integrated nitride semiconductor light emitting device of the present invention, at least a part of the plurality of light emitting devices configured as described above emits light from the light emitting layer of the light emitting device. A fluorescent material capable of absorbing at least a part of the light having a different wavelength and emitting light of another wavelength. A desired color tone can be easily set only by adjusting the type of the phosphor and the application location. In addition, since each light emitting surface has a large area and is close to each other, the color mixing of light between each light emitting surface is improved, and an integrated nitride semiconductor device capable of emitting light uniformly can be obtained.

The integrated nitride semiconductor device according to the first embodiment has a light emitting layer capable of emitting blue light, and the light emitted from the light emitting layer is excited on the upper surface of the light emitting layer. Yttrium activated with cerium that can emit light
A phosphor based on an aluminum oxide-based phosphor is applied.

Specific examples of the yttrium / aluminum oxide phosphor include YAlO ₃ : Ce, Y ₃ Al ₅ O.
₁₂ Y: Ce (YAG: Ce) or Y ₄ Al ₂ O ₉ : C
e, and mixtures thereof. Ba, Sr, M for yttrium / aluminum oxide phosphor
At least one of g, Ca, and Zn may be contained. Further, by containing Si, the reaction of crystal growth can be suppressed, and the phosphor particles can be made uniform.

In the present specification, the yttrium / aluminum oxide-based phosphor activated by Ce is to be interpreted in a particularly broad sense.
It is substituted with at least one element selected from the group consisting of Lu, Sc, La, Gd and Sm, or a part or the whole of aluminum is substituted with any one or both of Ba, Tl, Ga and In to have a fluorescent action. It is used in a broad sense, including phosphors.

More specifically, the general formula (Y _z Gd _{1 -z} ) ₃ A
l ₅ O _12: Ce (where, 0 <z ≦ 1) photoluminescence phosphor and the general formula represented by _{(Re 1-a Sm a)} 3 R
e ′ ₅ O ₁₂ : Ce (provided that 0 ≦ a <1, 0 ≦ b ≦ 1, R
e is at least one selected from Y, Gd, La, and Sc, and Re 'is at least one selected from Al, Ga, and In. ) Is a photoluminescent phosphor.

Since this phosphor has a garnet structure,
Resistant to heat, light and moisture, and has a peak in the excitation spectrum of 45
It can be set to around 0 nm. Also, the emission peak is near 580 nm and has a broad emission spectrum extending down to 700 nm.

The photoluminescent phosphor contains Gd (gadolinium) in the crystal, and thus has a 460
It is possible to increase the excitation light emission efficiency in a long wavelength region of not less than nm. Due to the increase in the Gd content, the emission peak wavelength shifts to a longer wavelength, and the entire emission wavelength shifts to the longer wavelength side.
That is, when a reddish luminescent color is required, it can be achieved by increasing the replacement amount of Gd. On the other hand, as Gd increases, the emission luminance of photoluminescence due to blue light tends to decrease. Further, Tb, Cu, Ag, Au, Fe, Cr, Nd, Dy, C
o, Ni, Ti, Eu and the like can be contained.

In addition, in the composition of the yttrium-aluminum-garnet-based phosphor having a garnet structure, the emission wavelength is shifted to a shorter wavelength side by partially replacing Al with Ga. Further, by substituting a part of Y in the composition with Gd, the emission wavelength shifts to the longer wavelength side.

When a part of Y is substituted with Gd, the substitution with Gd is less than 10%, and the content (substitution) of Ce is 0.0%.
It is preferable to set the value to 3 to 1.0. 2 substitutions with Gd
Below the percent, the green component is large and the red component is small,
By increasing the content of Ce, the red component can be supplemented, and a desired color tone can be obtained without lowering the luminance. With such a composition, the temperature characteristics are improved and the reliability of the light emitting diode can be improved. In addition, when a photoluminescent phosphor adjusted to have many red components is used, it is possible to emit an intermediate color such as pink, and an integrated nitride semiconductor light emitting device having excellent color rendering properties can be obtained.

Such a photoluminescent phosphor is
An oxide or a compound that easily becomes an oxide at a high temperature is used as a raw material for Y, Gd, Al, and Ce, and these are sufficiently mixed in a stoichiometric ratio to obtain a raw material. Or Y, Gd,
A coprecipitated oxide obtained by calcining a solution obtained by dissolving a rare earth element of Ce in an acid at a stoichiometric ratio with oxalic acid,
A mixed raw material is obtained by mixing with aluminum oxide. An appropriate amount of a fluoride such as barium fluoride or ammonium fluoride is mixed into the crucible as a flux, and the mixture is placed in a crucible.
Calcined in a temperature range of 0 to 1450 ° C. for 2 to 5 hours to obtain a calcined product, then ball-milled in water, washed,
It can be obtained by separating, drying and finally passing through a sieve.

In the light emitting diode of the present invention, such a photoluminescent phosphor may be a mixture of two or more kinds of yttrium aluminum garnet phosphor activated with cerium and other phosphors.

Further, the particle size of the phosphor used in the present invention is preferably in the range of 10 μm to 50 μm, and more preferably 15 μm to 30 μm. Thereby, light hiding can be suppressed and the luminance of the integrated nitride semiconductor light emitting device can be improved. Further, the phosphor having the above-mentioned particle size range has high light absorption and conversion efficiency, and has a wide excitation wavelength range. As described above, by incorporating a large-diameter phosphor having optically excellent characteristics, it is possible to satisfactorily convert and emit light around the main wavelength of the light-emitting element, and to provide an integrated nitride semiconductor light-emitting element. Mass productivity is improved.

On the other hand, a phosphor having a particle size of less than 15 μm relatively easily forms an aggregate, tends to settle down in the liquid resin, and reduces light transmission efficiency. .

In the present invention, the particle size is a value obtained from a volume-based particle size distribution curve. The volume-based particle size distribution curve is obtained by measuring the particle size distribution by a laser diffraction / scattering method. Specifically, in an environment at a temperature of 25 ° C. and a humidity of 70%, a hexametaline having a concentration of 0.05% Each substance is dispersed in an aqueous solution of sodium acid and a laser diffraction particle size distribution analyzer (SALD-2000A)
Is obtained in a particle size range of 0.03 μm to 700 μm. If the particle size when the integrated value is 50% in the volume-based particle size distribution curve is defined as the center particle size, the center particle size of the phosphor used in the present invention is 15 μm or more.
Preferably it is in the range of 50 μm. Further, it is preferable that the phosphor having the central particle size is contained frequently, and the frequency is preferably 20% to 50%. When a phosphor having a small variation in particle diameter is used as described above, color unevenness can be suppressed and an integrated nitride semiconductor light emitting device having a favorable color tone can be obtained.

On the other hand, a light emitting element capable of emitting ultraviolet light having a main emission peak in a short wavelength region around 400 nm, a red light capable of emitting visible light by such a short wavelength light,
By combining a phosphor capable of emitting blue and green light, an integrated nitride semiconductor light emitting device capable of emitting light uniformly can be obtained.

Specifically, Y ₂ O is used as the red phosphor.
₂ S: Eu, Sr ₅ (PO ₄ ) ₃ C as a blue phosphor
l: Eu and (SrEu) O.Al as green phosphor
₂ O ₃ is contained in resin or glass which is relatively resistant to ultraviolet rays,
White light can be obtained by applying a color conversion thin film layer to the surface of a light emitting element that emits short wavelength light.

In addition to the phosphor described above, 3.5 as a red phosphor
MgO · 0.5MgF ₂ · GeO ₂ : Mn, Mg ₆ As
_{2 O 11: Mn, Gd 2} O 2: Eu, LaO 2 S: E
u, as a blue phosphor, Re ₅ (PO ₄ ) ₃ Cl: Eu
(However, Re is at least one selected from Sr, Ca, Ba, and Mg), BaMg ₂ Al ₁₆ O ₂₇ : Eu, etc. can be suitably used. By using these phosphors, a white light emitting diode capable of emitting light with high luminance can be obtained.

When the color conversion thin film layer is composed of a mixture of two or more phosphors, it is preferable that the various phosphors have similar central particle diameters and shapes. Thereby, the color mixing of light emitted from various phosphors is improved, and color unevenness can be suppressed.

Further, a single layer having one kind of phosphor may be arranged in multiple layers. When three primary colors are obtained, a red phosphor layer, a green phosphor layer, and a blue phosphor layer are sequentially stacked on the device in consideration of the ultraviolet light transmittance of each phosphor, and all layers emit ultraviolet light. It can be absorbed preferably and is preferred. Further, it is preferable that such a color conversion multiple layer is laminated from the lower layer to the upper layer such that the particle diameter of the phosphor contained in each layer becomes smaller. Thereby, while being able to transmit ultraviolet light well to the top layer,
It is preferable because ultraviolet light can be completely absorbed in the color conversion multilayer. In addition, stripe, grid,
Alternatively, each color conversion layer can be arranged on the element so as to form a triangle.

In the present invention, it is sufficient that the phosphor is applied on at least the exposed p-side ohmic electrode of each of the light emitting elements. However, if the phosphor is applied over the side surface of each light emitting element, The light emitted from the side surface can be efficiently converted in color, and color unevenness is suppressed.
When an ultraviolet light emitting element is used, it is preferable to dispose the color conversion thin film layer so as to cover the entire periphery of the element, whereby the emission of ultraviolet light to the outside can be suppressed.

When the light-emitting element is provided on one main surface of the light-transmitting substrate and light is extracted from the light-transmitting substrate side by flip-mounting the light-emitting element, the other light-emitting element is provided on the other main surface of the light-transmitting substrate. By coating a phosphor on the surface, a color conversion type light emitting element capable of emitting light in a large area can be obtained.

In the present invention, the method of applying the phosphor is not particularly limited, and the phosphor alone may be directly applied by vacuum evaporation or CVD, or the phosphor may be attached together with a binder. The material of the binder is not particularly limited, and any of an organic substance and an inorganic substance can be used.

When an organic substance is used as a binder,
As a specific material, a transparent resin having excellent light resistance such as an epoxy resin, an acrylic resin, or silicone is suitably used.

When an inorganic material is used as the binder, an integrated nitride semiconductor light emitting device which can maintain its reliability even when a large current is applied can be obtained.

As a specific coating method, a sedimentation method, a sol-gel method and the like can be mentioned. For example, phosphor, silanol (S
i (OEt) ₃ OH) and ethanol are mixed to form a slurry, and the slurry is discharged from a nozzle toward the p-side ohmic electrode side of the integrated nitride semiconductor layer, and dried by blowing heated air. Thereby, the silanol is converted into a sol to form SiO ₂ , and the phosphor can be fixed.

Further, an inorganic binder may be used as the binder. The binder is a so-called low-melting glass, and it is preferable that the binder is extremely stable in a binder with a small particle and a small absorption with respect to radiation from the ultraviolet to the visible region, and a fine particle obtained by a precipitation method. The alkaline earth borate particles are suitable. Also, when attaching a phosphor having a large particle size, a binder in which the particles are ultrafine even if the melting point is high, for example, silica, alumina manufactured by Degussa, or an alkali having a fine particle size obtained by a precipitation method. It is preferable to use an earth metal pyrophosphate, orthophosphate or the like.

These binders can be used alone or as a mixture with one another.

Here, a method of applying the binder will be described. It is preferable that the binder is wet-pulverized in a vehicle and used in the form of a slurry, since the binding effect can be sufficiently enhanced. The vehicle is a high-viscosity solution obtained by dissolving a small amount of a binder in an organic solvent or deionized water.
For example, by adding 1 wt% of nitrocellulose as a binder to butyl acetate as an organic solvent,
An organic vehicle is obtained.

A phosphor is added to the binder slurry thus obtained to prepare a coating solution. The total amount of the binder in the slurry is 1 to the amount of the phosphor in the coating solution.
It is preferably about 3% wt, so that the phosphor can be satisfactorily fixed and the luminous flux maintenance rate can be maintained. If the added amount of the binder is too large, the luminous flux maintenance ratio tends to decrease. Therefore, it is preferable to use the binder in a minimum amount.

After applying the coating solution on the semiconductor layer, hot air or hot air is blown to dry. Thereby, the phosphor layer is attached to the surface of the window with the binder. (Diffusing Agent) Further, in the present invention, a diffusing agent may be contained in the color conversion member in addition to the phosphor. As a specific diffusing agent, barium titanate, titanium oxide, aluminum oxide, silicon oxide, or the like is suitably used. Thus, an integrated nitride semiconductor light emitting device having good directivity characteristics can be obtained.

Here, in the present specification, the diffusing agent refers to a material having a center particle diameter of 1 nm or more and less than 5 μm. The diffusing agent having a size of 1 μm or more and less than 5 μm is preferable because light from the light emitting element and the phosphor is diffused favorably, and color unevenness which is likely to be caused by using a phosphor having a large particle diameter is preferable. Further, the half width of the emission spectrum can be narrowed, and an integrated nitride semiconductor light emitting device with high color purity can be obtained. On the other hand, a diffusing agent having a thickness of 1 nm or more and less than 1 μm has a low interference effect on the light wavelength from the light emitting element, but can increase the resin viscosity without reducing the luminous intensity. Thereby, when disposing the color conversion member by potting or the like, it becomes possible to disperse the phosphor in the resin almost uniformly in the syringe and to maintain the state, and the fluorescent substance having a large particle diameter, which is relatively difficult to handle, Even when a body is used, it is possible to produce with good yield. Thus, the action of the diffusing agent in the present invention varies depending on the particle size range,
They can be selected or combined in accordance with the method of use. (Filler) In the present invention, a filler may be contained in the color conversion member in addition to the phosphor. The specific material is the same as the diffusing agent, but the central particle size is different from that of the diffusing agent. In this specification, the filler refers to a material having a central particle size of 5 μm or more and 100 μm or less. When a filler having such a particle diameter is contained in the color conversion member, the chromaticity variation of the integrated nitride semiconductor light emitting device is improved by the light scattering action, and the thermal shock resistance of the light transmitting resin of the color conversion member is improved. Can be increased. Thereby, a highly reliable integrated nitride semiconductor light emitting device can be obtained.

When a liquid mixture of a liquid binder and a phosphor is used as the coating liquid, the filler is added to the coating liquid to maintain the fluidity of the liquid binder constant for a long time. It becomes possible. This allows
The coating liquid can be accurately arranged at a desired place, and the yield is improved.

The filler preferably has a particle size and / or shape similar to that of the phosphor. Here, in the present specification, the term “similar particle size” refers to a case where the difference between the respective center particle sizes of the respective particles is less than 20%. This refers to a case where the difference in the represented circularity (circularity = perimeter of a perfect circle equal to the projected area of a particle / perimeter of the projection of a particle) is less than 20%. By using such a filler, the phosphor and the filler interact with each other, the phosphor can be favorably dispersed in the binder, and color unevenness is suppressed. Further, both the phosphor and the filler preferably have a center particle diameter of 15 μm to 50 μm, more preferably 20 μm to 50 μm. By adjusting the particle diameters in this way, a preferable interval is provided between the particles. be able to. As a result, a light extraction path is secured, and the directional characteristics can be improved while suppressing a decrease in luminous intensity due to mixing of the filler. (Pixel) In this specification, a pixel indicates a color tone observed at a short distance from each light-emitting surface when a current flows through the integrated nitride semiconductor device. Second Embodiment FIG. 4 shows an integrated nitride semiconductor light emitting device according to a second embodiment. The integrated nitride semiconductor device has a light emitting layer capable of emitting blue light. Also, the first
A red phosphor 72 capable of absorbing a part of the blue light and emitting red light is applied to the semiconductor layer side of the light emitting element 1, and the third light emitting element 3 is similarly coated with one of the blue light. A green phosphor 74 capable of absorbing a portion and emitting a green wavelength is applied. Thereby, the first light emitting element 1
Has a red pixel, the second light emitting element 2 has a blue pixel, and the third light emitting element 3 has a green pixel.

Since the integrated nitride semiconductor device has pixels of three primary colors on the same substrate, a white light emitting device having excellent color rendering properties can be obtained. Each light emitting element used in the present invention has a semiconductor layer made of the same material, and a current is injected almost uniformly to the entire light emitting layer, so that light is uniformly applied to the phosphor disposed on the light emitting layer. Can supply. This makes it possible to obtain uniform pixels without uneven light emission. In the integrated nitride semiconductor device according to the present invention, the distance between the light emitting devices is preferably 50 μm to 150 μm, more preferably 50 μm to 100 μm, and still more preferably 50 μm to 50 μm.
80 μm. In addition, such an isolation groove is formed in a stripe shape and has a long light emitting layer in one direction, so that each pixel can be uniformly mixed.

Further, by adjusting the coating amount of the phosphor in each element, it is possible to easily obtain a subtle intermediate color which has been difficult so far. Third Embodiment Parallel Connection Next, an integrated nitride semiconductor light emitting device according to a third embodiment of the present invention will be described with reference to FIG.

The integrated nitride semiconductor light emitting device of the third embodiment differs from the integrated nitride semiconductor light emitting device of the first embodiment in the following points.

Differences In the integrated nitride semiconductor light emitting device of the first embodiment, the insulating protection film 30 is formed so as to cover the entire device without forming the connection electrode 21 and the external connection electrodes 24 and 26, and A through-hole 61 is formed on the p-pad electrode 3 through the insulating protective film 30, and a through-hole 62 is formed on the n-side ohmic electrode of each of the light emitting elements 1, 2 and 3 through the insulating protective film 30. I do.

Difference 2. The connection electrodes 51 connect the p pad electrodes of the light emitting elements 1, 2, and 3 to each other via the through holes 61 formed in the insulating protection film 30.

Difference 3 The n-side ohmic electrodes of the light emitting elements 1, 2, and 3 are connected to each other by the connection electrode 52 via the through hole 62 formed in the insulating protection film 30.

Except for the differences 1, 2 and 3, the configuration is the same as that of the integrated nitride semiconductor light emitting device of the first embodiment.

That is, the integrated nitride semiconductor light emitting device of the third embodiment is obtained by connecting the light emitting devices 1, 2, and 3 in parallel with the device of the first embodiment.

The integrated nitride semiconductor light emitting device according to the third embodiment configured as described above can improve the luminous efficiency similarly to the first embodiment.

In the first, second, and third embodiments, the case in which the number of light emitting elements is three has been described. However, the present invention is not limited to this, and is configured using two light emitting elements. Alternatively, the light emitting element may be configured by three or more light emitting elements.

In the first, second and third embodiments, as the most preferable example, the distances L1, L2 and L3 between the long side outside the light emitting layer 10 (p layer 13) and the n-side ohmic electrode are set to 22.
Although the case where it is set to 0 μm has been described, the present invention is not limited to this, and may be set to 250 μm or less, preferably 220 μm or less.

[0108]

Embodiments of the present invention will be described below. Note that the present invention is not limited to this. [Example 1] (Substrate 11) The substrate 11 made of sapphire (C-plane) was M
Set in the OVPE reaction vessel, while flowing hydrogen,
The temperature of the substrate is raised to 1050 ° C., and the substrate is cleaned. Other examples of the substrate 11 include a sapphire substrate having an R surface and an A surface as main surfaces, and spinel (MgAl ₂ O ₄ ).
Such as an insulating substrate may be used. (N-type gallium nitride-based compound semiconductor layer 12) After cleaning the substrate, the n-type gallium nitride-based compound semiconductor layer 12 is grown in the following configuration.

The temperature of the substrate was lowered to 510 ° C.
A GaN buffer layer is grown thereon by 100 °.

Next, after growing the buffer layer, the temperature is increased to 1050 ° C.
Undoped GaN layer 121 to 1.5 μm
It grows with the film thickness of.

Subsequently, at 1050 ° C., 4.5 × 10
^{A 18} / cm ³ doped GaN layer 122 is grown to a thickness of 2.2 μm.

Subsequently, at 1050 ° C., the undoped GaN layer 123 was formed to a thickness of 3000
0 ¹⁸ / cm ³ doped GaN layer 124 at 300 °
Further, an undoped GaN layer 125 is grown to a thickness of 50 °.

Subsequently, at the same temperature, the first layer made of undoped GaN is set at 40 ° C. and the temperature is set at 800 ° C., and then the second layer made of undoped In _0.13 Ga _0.87 N is formed.
Are grown at a film thickness of 20 °, these operations are repeated, and ten layers are alternately stacked in the order of 1 + 2 +, and finally, the n-type multilayer film layer 126 in which the first layer is stacked is formed. Let it grow. (Light Emitting Layer 10) Next, after growing an n-type gallium nitride based compound semiconductor layer 12, a barrier layer made of
Grown at a thickness of 0 °, followed by a temperature of 800 ° C.
In _0.3 Ga doped with 5 × 10 ¹⁷ / cm ^{3 of} Si
_{A 0.7} N well layer is grown to a thickness of 30 °.
.., Six barrier layers and five well layers are alternately stacked in the order of barrier + well + barrier + well.
The light emitting layer 10 composed of the multiple quantum wells is stacked. (P-type gallium nitride compound semiconductor layer 13) Light emitting layer 10
After the growth, the p-type gallium nitride based compound semiconductor 13 is grown in the following configuration.

Next, at 1050 ° C., Mg was added to 5 × 10 ¹⁹ /
A ^third layer of cm ³ -doped p-type Al _0.1 Ga _0.9 N is grown to a thickness of 25 °, followed by a fourth layer of undoped GaN to a thickness of 25 °, Is repeated to grow a p-type multilayer film layer composed of a superlattice in which four layers are alternately stacked in the third + fourth order with a thickness of 200 °.

Subsequently, at 1050 ° C., Mg was added to 1 × 10 ²⁰
/ Cm ³ doped p-type GaN layer at 2700 °
It grows with the film thickness of.

After the completion of the reaction, the temperature is lowered to room temperature, and annealing is performed at 700 ° C. in a nitrogen atmosphere to further reduce the resistance of the p-type layer.

The wafer on which the gallium nitride-based compound semiconductor has been grown as described above is taken out of the reaction vessel, and a SiO ₂ mask is formed on the entire wafer except for a portion where a separation groove is to be formed, and reaches the sapphire substrate by RIE. The isolation groove is formed by performing the etching up to this point.

Further, in order to expose the n-type gallium nitride-based compound semiconductor layer 12 by removing the SiO ₂ mask used for forming the separation groove, the p-type gallium nitride-based compound semiconductor layer 13 excluding the exposed portion was removed. An SiO ₂ mask is formed, etching is performed by RIE, and the n-type gallium nitride-based compound semiconductor layer 12 (Si-doped GaN layer 12
The surface of 2) is exposed.

Next, the p-type gallium nitride compound semiconductor layer 1
3 is coated with a resist so as to cover almost the entire surface, and the other portions are covered. Ni is stacked on the opened p-type gallium nitride-based compound semiconductor layer at 100 ° and Pt at 500 °, and then annealed to form a p-side ohmic electrode 15. To form Further, a part of the p-side ohmic electrode is made of Pt 3000 ° and Ni 60
A p-side pad electrode 16 made of Å is formed.

Next, the resist was removed, and this time, W was set to 200 ° and Al was set to 10
00Å, W 500Å, Pt 3000Å, Ni 60
The n-side ohmic electrode 14 laminated in the order of Å is formed.

Next, an insulating protective film 1 made of SiO ₂ is formed on the entire surface.
7 is formed with a thickness of 1.5 μm, and a part of the p-side pad electrode and the n-side ohmic electrode is exposed by RIE.

Further, as a connection electrode for electrically connecting a p-side pad electrode and an n-side ohmic electrode sandwiching a separation groove by forming a mask so as to open a portion where a connection electrode is to be formed on the surface, Ti is 400 °, Pt is used. Is formed to a thickness of 6000 °, Au to a thickness of 1000 °, and Ni to a thickness of 60 °.

Finally, an insulating protective film 30 made of SiO ₂ is formed with a thickness of 1.5 μm, and the insulating protective film 30 on the connection electrodes 24 and 26 is subjected to RIE so that it can be electrically connected to the outside.
Then, the integrated nitride semiconductor device is completed by etching. (Phosphor coating) Next, the exposed portion of the p-side ohmic _{electrode, (Y} 0.995 _{Gd 0 .005)
2.750} Al ₅ O ₁₂ : Ce _{0.250 The} phosphor 71 is fixed with a binder.

The sapphire substrate (wafer) having a plurality of element regions manufactured as described above is scribed and diced to form a 1000 μm × 1000 μm first sapphire substrate.
A light-emitting element, a second light-emitting element, and a third light-emitting element
The device shown in FIG. 1 in which two nitride semiconductor devices are connected in series is manufactured.

The integrated nitride semiconductor device having such a structure has an operating voltage of 10.5 V and a conventional 300 μm ×
It shows luminous efficiency equivalent to 300 μm (operating voltage 3.5 V). Further, substantially uniform light emission can be obtained on the light emitting surface of each element. As a result, uniform white light with high brightness over a large area can be obtained. This element has an operating voltage of 10.5.
Since the voltage is V, it can be used on a battery power supply (12 V) via a control device such as a resistor. [Example 2] In Example 1, a red phosphor 72 capable of absorbing light from the blue light emitting element and emitting red light was used as a binder on the upper surface and the end surface of the first light emitting element 1. Similarly, a green phosphor 74 capable of absorbing light from the blue light emitting element and emitting green light is fixed to the upper surface and the end surface of the third light emitting element 3 with a binder. With the same configuration as in Example 1 except for the above, the same effect as in Example 1 is obtained, and white light with excellent color rendering properties is obtained. [Example 3] In Example 2, (1) a light emitting element chip capable of emitting light in the ultraviolet region is used instead of the light emitting element capable of emitting blue light. (2) As the phosphors, three kinds of phosphors capable of absorbing the light in the ultraviolet region and emitting light can emit the red phosphor 72, the blue phosphor 73, and the green phosphor 74. The first light-emitting element 1, the second light-emitting element 2, and the third light-emitting element 3 are fixed to the semiconductor layer side, respectively.

Except for this point, when the configuration is the same as that of the first embodiment, the same effect as that of the first embodiment can be obtained. Further, in this embodiment, since the luminescent color is obtained only by the light emitted from the phosphor, white light having excellent color mixing properties and little color variation can be obtained.

[0127]

As described in detail above, in the integrated nitride semiconductor light emitting device according to the present invention, the distance between one long side of the p layer and the n-side ohmic electrode is set to 250 μm or less. Therefore, current can be injected almost uniformly into the entire light emitting layer of each light emitting element. Accordingly, light can be uniformly supplied to the entire phosphor disposed on the light emitting surface, and the light emitting efficiency of each light emitting element can be improved.

Further, in the integrated nitride semiconductor light emitting device according to the present invention, each light emitting device can be made sufficiently long in one direction (longitudinal direction) without deteriorating uniform light emission and light emission efficiency. Since the area can be increased and the luminous efficiency can be increased, a nitride semiconductor light-emitting device having a large area and good luminous efficiency can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an integrated nitride semiconductor light emitting device according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view taken along line AA ′ of FIG.

FIG. 3 is a cross-sectional view illustrating a stacked structure of an n-type gallium nitride-based compound semiconductor layer.

FIG. 4 is a plan view of an integrated nitride semiconductor light emitting device according to a second embodiment of the present invention.

FIG. 5 is a plan view of an integrated nitride semiconductor light emitting device according to a third embodiment of the present invention.

FIG. 6 is a plan view of an integrated nitride semiconductor light emitting device according to a third embodiment of the present invention.

[Explanation of symbols]

 1, 2, 3 ... light emitting element, 10 ... light emitting layer, 11 ... sapphire substrate, 12 ... n-type gallium nitride based compound semiconductor layer, 13 ... p-type gallium nitride based semiconductor layer, 14 ... n-side ohmic electrode, 15 ... p Side ohmic electrode, 16: p pad electrode, 17: insulating protective film, 71, 72, 73, 74: phosphor 21, 51, 52: connecting electrode, 24, 26: external connecting electrode, 30: insulating protective film, 61 Reference numerals 62, through holes, 41, separation grooves, 121, undoped GaN layers, 122, undoped GaN layers, 123, undoped GaN layers, 124, undoped GaN layers, 125, undoped GaN layers, 126, multilayer film layers.

Claims (6)

[Claims] 1. A plurality of light emitting elements are juxtaposed on the same substrate, each of the plurality of light emitting elements has a semiconductor layer made of the same material, and the semiconductor layer is formed on the same substrate. The n-type gallium nitride-based compound semiconductor layer separated by a separation groove, a light-emitting layer made of a gallium nitride-based compound semiconductor, and a p-layer made of a p-type gallium nitride-based compound semiconductor An integrated nitride semiconductor light emitting device comprising: one long side and two short sides of the n layer are close to one long side and two short sides of the light emitting layer and the p layer, respectively. An n-side ohmic electrode having substantially the same length as the long side of the p-layer on the n-layer between the other long side of the n-layer and the other long side of the p-layer; A p-side ohmic electrode is formed on almost the entire surface of the p-layer, A plurality of p-pad electrodes provided on one side of the p-layer along one long side of the p-layer; a distance between one long side of the p-layer and the n-side ohmic electrode is 250 μm or less; At least some of the light-emitting elements have, on the top surface of the semiconductor layer, a phosphor capable of absorbing at least a part of light emitted from the light-emitting layer and emitting different wavelengths. An integrated nitride semiconductor light emitting device characterized by the following. 2. The integrated nitride according to claim 1, wherein three light emitting elements are arranged in a set on the same substrate, and pixels of three different colors are obtained from the set. Semiconductor light emitting device. 3. The integrated nitride semiconductor light emitting device according to claim 1, wherein said light emitting layer emits blue light. 4. The integrated nitride semiconductor light emitting device according to claim 1, wherein the light emitting layer emits light in an ultraviolet region. 5. The integrated nitride semiconductor light emitting device according to claim 1, wherein the plurality of light emitting devices are connected in series. 6. The integrated nitride semiconductor light emitting device according to claim 1, wherein the plurality of light emitting devices are connected in parallel.