JP6136624B2 - Light emitting element - Google Patents

Description

  The present invention relates to a compound semiconductor light emitting device, and more particularly to a compound semiconductor light emitting device having a pad electrode portion.

  In recent years, LEDs (light emitting diodes) have been adopted for mobile devices. In order to incorporate LEDs in mobile devices, a small module is required, which requires a smaller volume for the chip. In particular, since the chip thickness determines the thickness of the module, realizing a thin chip is the key to reducing the volume.

On the other hand, in order to produce a thin chip, it is necessary to thin the wafer after device formation, and the cost required for processing becomes a factor that raises the chip cost. There is also a problem of yield reduction due to processing. Furthermore, a thin light emitting element cannot provide an epitaxial film thickness sufficient for current diffusion.
A light-emitting element that does not perform sufficient current diffusion easily concentrates light directly under the electrode because the current is concentrated on a part of the light-emitting element, and the EL ( Electro-Luminescence ) emission distribution is not uniform. Light output cannot be earned.

In order to avoid the above, it is important to avoid the concentration of current directly under the electrode. Therefore, as shown in Patent Document 1, it has been proposed to provide a block layer made of an insulator such as SiO ₂ immediately below the electrode.
Patent Document 2 describes that a transparent conductive layer is provided, a reduction electrode containing a substance that reduces the transparent electrode layer is provided in the pad electrode, and a block layer is provided below the reduction electrode layer.

JP 2012-160665 A JP 2012-186199 A

  As described above, when an LED is employed in a mobile device, it is desired to avoid the concentration of current immediately below the electrode. For this reason, proposals such as Patent Document 1 and Patent Document 2 have been proposed.

However, the inventors have found that there are the following problems.
That is, in the method described in Patent Document 1, since an insulator is inserted directly under the electrode, it is effective to prevent a current from flowing directly under the electrode. However, for film formation and pattern formation of SiO _2. Photolithography process, etching process and many processes are required.
When SiO ₂ is formed as a block layer, the material cost of the block layer itself is lower than that of a block layer made of semiconductor. However, since an alloy layer is not formed at the interface between the semiconductor layer and the ohmic metal layer, it is in a so-called adhesion state and easily peels off against physical force. As a result, electrode peeling is likely to occur, which is not a preferable method.
In order to avoid peeling, it is necessary to maintain or increase the thickness of the pad electrode portion itself, which increases the cost. Essentially, it is preferable to have an alloy layer at the contact portion between the pad electrode portion and the semiconductor in order to prevent electrode peeling.
In terms of peeling, Patent Document 2 in which the transparent conductive layer and the pad metal part form an alloy layer has a more preferable structure than Patent Document 1, but the formation of the transparent conductive layer, the formation of the reduction electrode layer, and the like. The photolithography process, electrode pattern formation, and Patent Document 2 require more processes than Patent Document 1.
In addition, providing the block layer as an epitaxial layer is not a preferable method for manufacturing an inexpensive chip because it causes a much larger cost increase than providing an SiO ₂ film or a transparent conductive film.

  That is, although Patent Document 1 and Patent Document 2 are effective in preventing current from flowing directly under the pad electrode, many additional steps are required, and the cost for forming the electrode increases. Then, it was difficult to reduce the chip cost while maintaining the light emission output.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a light emitting element having a chip structure that is inexpensive and can suppress the occurrence of electrode peeling while maintaining the light output from the chip. .

  In order to achieve the above object, the present invention provides a light emitting part in which at least a first semiconductor layer having a first conductivity type, an active layer, and a second semiconductor layer having a second conductivity type are formed in this order; A first electrode part having a pad electrode part in contact with the two semiconductor layers and a thin wire electrode part in contact with the second semiconductor layer and connected to the pad electrode part; and a second electrode part provided on the first semiconductor layer side In the case where the second semiconductor layer is n-type, the pad electrode portion includes one or more kinds of metals of Al, Ag, Au, Pt, Cu, Ti, and Ni. It has a layer structure equal to or more than one layer, and the pad electrode portion does not include a metal that becomes a p-type dopant or a metal that becomes an n-type dopant with respect to the second semiconductor layer, or p with respect to the second semiconductor layer. One or more types of metals to be type dopants The thin wire electrode portion is composed of one or more layers including one or more kinds of metals of Al, Ag, Au, Pt, Cu, Ti, and Ni, and the thin wire electrode portion is formed on the second semiconductor layer. On the other hand, when the second semiconductor layer is p-type and includes one or more kinds of metals that are n-type dopants, the pad electrode portion is any one of Al, Ag, Au, Pt, Cu, Ti, and Ni. It has a layer structure of one or more layers containing the above metal, and the pad electrode portion does not contain a metal that becomes a p-type dopant or a metal that becomes an n-type dopant with respect to the second semiconductor layer, or the second The semiconductor layer includes one or more kinds of metals serving as n-type dopants, and the thin wire electrode portion includes one or more kinds of metals including any one or more kinds of metals of Al, Ag, Au, Pt, Cu, Ti, and Ni. It consists of a layer structure, and the thin wire electrode part is To provide a light emitting device which comprises one or more metals to be a p-type dopant to the secondary semiconductor layer.

As described above, the pad electrode portion, the fine wire electrode portion, and the second semiconductor layer are configured as described above, so that ohmic contact is not caused between the pad electrode portion and the second semiconductor layer, and Schottky is provided. Because the contact is made, the region immediately below the pad electrode portion has high resistance, while the thin wire electrode portion and the second semiconductor layer are in ohmic contact and the region immediately below the thin wire electrode portion has low resistance. Since current does not flow and current flows only in the thin wire electrode portion, the current concentrates in the thin wire electrode portion, and the same effect as when a block layer is provided directly below the pad electrode can be obtained. A light emitting element can be realized.

Here, it is preferable that a window layer having a thickness of 10 μm or more is formed on the side of the first semiconductor layer opposite to the active layer.
By forming such a window layer, light from the light emitting portion is more easily emitted to the outside of the light emitting element, so that a light emitting element with higher luminance can be obtained.

Moreover, it is preferable to have a composition adjustment layer between the first semiconductor layer and the window layer.
Thus, by having a composition adjustment layer between the first semiconductor layer and the window layer, when the lattice constants of the first semiconductor layer and the window layer are different, the crystallinity is good on the first semiconductor layer. The window layer can be epitaxially grown.

Here, a supporting substrate having the second electrode on the lower surface, a bonding metal layer provided on the supporting substrate and functioning as a reflective layer, and a dielectric provided between the bonding metal layer and the first semiconductor layer The semiconductor device may further include a body layer and an interface electrode that penetrates a part of the dielectric layer and contacts the bonding metal layer and the first semiconductor layer.
With such a configuration, a reflective layer can be provided on the first semiconductor layer side of the light-emitting portion, so that a light-emitting element with higher luminance can be realized.

Here, the second semiconductor layer is made of an AlGaInP-based compound semiconductor, an AlGaInN-based compound semiconductor, or an AlGaAs-based compound semiconductor, and the metal serving as a p-type dopant for the second semiconductor layer is Be, Zn, Mg , C, and the metal serving as an n-type dopant for the second semiconductor layer may be any of S, Se, Si, and Ge.
Thus, when the second semiconductor layer is made of an AlGaInP-based compound semiconductor, an AlGaInN-based compound semiconductor, or an AlGaAs-based compound semiconductor, the above dopant metal can be preferably used.

Here, it is preferable that the thickness of the pad electrode part is 200 nm or more thicker than the fine wire electrode part, and the width of the electrode at the boundary between the pad electrode part and the fine wire electrode part is 5 μm or more.
By setting it as the thickness of such a pad electrode part, the thickness which can absorb the impact at the time of wire bonding is securable.
Further, by setting the electrode width at the boundary between the pad electrode portion and the fine wire electrode portion as described above, the pad electrode portion and the fine wire electrode portion can be electrically connected with a low resistance.

The active layer is made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.35 ≦ y ≦ 0.65), and the first semiconductor layer and the second semiconductor layer Can be made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.35 ≦ y ≦ 0.65).

The active layer is made of (Al _x Ga _1-x ) _y In _1-y N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1), and the first semiconductor layer and the second semiconductor layer are (Al _x Ga _1-x ) _y In _1-y N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1).

Further, the active layer is made of (Al _x Ga _1-x ) As (0 ≦ x ≦ 1), and the first semiconductor layer and the second semiconductor layer are (Al _x Ga _1-x ) As (0 ≦ x ≦ ₁ ). 1) or (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.35 ≦ y ≦ 0.65).
Thus, the above materials can be suitably used as the active layer, the first semiconductor layer, and the second semiconductor layer of the light emitting unit.

  As described above, according to the present invention, the dopant metal contained in the pad electrode portion and the fine wire electrode portion is changed according to the conductivity type of the second semiconductor layer, thereby suppressing the current flowing directly under the pad electrode portion. In addition to allowing current to flow directly under the thin wire electrode part, an alloy layer can be formed at the interface between the pad electrode part and the second semiconductor layer. A light-emitting element having a chip structure that can be suppressed can be realized.

It is sectional drawing of the epitaxial wafer used in order to manufacture the light emitting element of 1st embodiment of this invention. It is a schematic sectional drawing of the light emitting element of 1st embodiment of this invention. It is a top view of the light emitting element of 1st embodiment of this invention. It is a bottom view of the light emitting element of 1st embodiment of this invention. It is sectional drawing of the epitaxial wafer used in order to manufacture the light emitting element of 2nd embodiment of this invention. It is process sectional drawing which shows the manufacturing process of the light emitting element of 2nd embodiment of this invention. It is a schematic sectional drawing of the light emitting element of 2nd embodiment of this invention. It is a top view of the light emitting element of the second embodiment of the present invention. 6 is a top view of a light emitting element of Comparative Example 1. FIG. 6 is a top view of a light emitting device of Comparative Example 2. FIG. FIG. 10 is a top view of a light emitting element of Comparative Example 3. 6 is a top view of a light emitting device of Comparative Example 4. FIG. It is a graph which shows the relative light emission output with respect to Example 1 of the comparative example 1 thru | or the comparative example 3. FIG. It is a graph which shows the increase rate of the light emission output of the light emitting element of Example 2 with respect to the light emitting element of the comparative example 4, VF value, and luminous efficiency.

Hereinafter, the present invention will be described in detail as an example of an embodiment with reference to the drawings, but the present invention is not limited thereto.
As described above, when an LED is used in a mobile device, it is desired to avoid the concentration of current immediately below the electrode.
Various technologies have been proposed to avoid current concentration directly under the electrode, but many additional steps are required, and the cost for forming the electrode increases, and the conventional technology maintains the light output. However, it was difficult to reduce the chip cost.

Therefore, the inventors have made extensive studies on a light emitting element that can reduce the chip cost while maintaining the light emission output.
As a result, by changing the dopant metal contained in the pad electrode portion and the fine wire electrode portion according to the conductivity type of the second semiconductor layer, the current flowing directly under the pad electrode portion is suppressed, while the current is directly under the fine wire electrode portion. Since an alloy layer can be formed at the interface between the pad electrode portion and the second semiconductor layer, the chip cost can be reduced while maintaining the light emission output, and the occurrence of electrode peeling can be suppressed. The headline and the present invention were made.

First, the light emitting element of 1st embodiment of this invention is demonstrated using FIG. 1 thru | or FIG.
FIG. 1 is a cross-sectional view of an epitaxial wafer used for manufacturing the light emitting device of the first embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view of the light emitting device of the first embodiment of the present invention.
FIG. 3 is a top view (a plan view seen from the second semiconductor layer side) of the light emitting device according to the first embodiment of the present invention.
FIG. 4 is a bottom view (a plan view seen from the window layer side) of the light emitting device according to the first embodiment of the present invention.
As shown in FIG. 1, an epitaxial wafer 100 is formed with a buffer layer 102 and an etching stop layer 103 on a starting substrate 101, and then a second conductivity type second semiconductor layer 104, an active layer 105, a first conductivity type. The light emitting portion 120 is formed by stacking the first semiconductor layers 106.
For example, when the starting substrate 101 is GaAs, the material of the light emitting portion is (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ _1, 0, 35 ≦ y ≦ 0.65), Al _z Ga _1-z As (0 ≦ z ≦ 1) or (Al _x Ga _1-x ) _y In _1-y N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1) can be selected.
Further, when the starting substrate 101 is Ge or ZnO, the buffer layer 102 is a layer including an effect of adjusting the lattice irregularity.
The active layer 105 is adjusted to a composition having a band gap smaller than that of the first semiconductor layer 106 and the second semiconductor layer 104 in order to produce a carrier confinement effect.

A window layer 108 is formed on the light emitting unit 120 by epitaxial growth.
When the starting substrate 101 is GaAs, the window layer 108 can be selected from any material that does not diffuse impurities into the substrate during growth, but is transparent to the light emitted from the active layer 105. Certain GaPAs, GaP, AlGaAs, AlAs, GaPN, etc. can be selected.
Further, the thicker the window layer 108, the higher the light extraction effect. Although an increase in light extraction effect can be expected even with a thickness of about 1 μm, it is preferable to provide a window layer with a thickness of 10 μm or more for a later process.
Further, in the case where the lattice constants are significantly different between the window layer 108 and the second semiconductor layer 106, it is more effective to suppress the surface roughness by providing the composition adjustment layer 107, but there is no composition adjustment layer 107. May be.

The second semiconductor layer 104 is effectively provided with a region having two or more kinds of doping concentrations in order to enhance the current dispersion effect. A layer in which the doping concentration of one layer is more than twice the doping concentration of the other layer is arranged in two or more layers from the region on the starting substrate 101 side of the second semiconductor layer 104 to the direction in contact with the active layer 105. Is preferred.
That is, current is dispersed in the lateral direction at the interface between the low-concentration doping layer and the high-concentration doping layer, and the current flows through the high-concentration doping layer with low resistance, thereby realizing effective current dispersion even in a thin film. be able to.
When a plurality of pairs of the low-concentration doping layer and the high-concentration doping layer are combined, the effect of current dispersion can be further enhanced.

The effect of current dispersion is remarkable in the region where the doping concentration of the low-concentration doping layer is 3 × 10 ¹⁷ / cm ³ or less and the doping concentration of the high-concentration doping layer is 6 × 10 ¹⁷ / cm 3. ^Three or more areas.
The effect of current dispersion is an effect due to a difference in doping concentration, and the low-concentration doping layer only needs to have a thickness of 50 nm or more when the epitaxial layer is formed.
Even if the low concentration doping layer is higher than 3 × 10 ¹⁷ / cm ³ and the high concentration doping layer is less than 6 × 10 ¹⁷ / cm ³ , two or more pairs of the low concentration doping layer and the high concentration doping layer can be provided. In this case, since the film thickness is increased, the cost can be increased, but the same effect can be obtained.

In this embodiment, the window layer 108 is of the first conductivity type (that is, the same conductivity type as the first semiconductor layer 106), and preferably has a doping concentration of 1 × 10 ¹⁷ / cm ³ or more.
When the doping concentration of the first semiconductor layer 106 is uniform and the doping concentration of the region of the window layer 108 is less than 1 × 10 ¹⁷ / cm ³ , current dispersion is inhibited and light emission from the active layer is uniform. It may not be possible.
When the doping concentration in the region of the window layer 108 is less than 1 × 10 ¹⁷ / cm ³ , the first semiconductor layer is formed in the same manner as the second semiconductor layer 104 in order to make current distribution uniform. 106 preferably has two types of doping regions of low concentration and high concentration.

After the window layer 108 is formed, a dot electrode 401 is formed so as to be in contact with the window layer 108 as shown in FIG.
Thereafter, the starting substrate 101 and the buffer layer 102 are removed. For example, when the starting substrate 101 is GaAs, it is removed with a mixed solution of ammonia and hydrogen peroxide.
For example, when the etching stopper layer 103 is an AlInP layer, the etching stops at the etching stopper layer 103 due to the selectivity of etching when the above-described mixed solution is used.
After removing the starting substrate 101 and the buffer layer 102, the etching stop layer 103 is removed, and the second semiconductor layer 104 is exposed.
The etching stopper layer 103 can be selectively removed by using, for example, an SPM (sulfuric acid / hydrogen peroxide) solution.

  Thereafter, as shown in FIG. 2, the exposed second semiconductor layer 104 has a structure of one or more layers made of a metal including one or more of Al, Ag, Au, Pt, Cu, Ti, and Ni. A thin wire electrode portion 301 is formed. When the second conductivity type (that is, the conductivity type of the second semiconductor layer 104) is p-type, the thin wire electrode portion 301 has one or more kinds of metals of Be, Zn, Mg, and C (that is, the second semiconductor layer 104). A metal which becomes a p-type dopant). When the second conductivity type is n-type, the thin wire electrode portion 301 includes one or more kinds of metals of S, Se, Si, and Ge (that is, a metal that becomes an n-type dopant with respect to the second semiconductor layer 104). .

The thin wire electrode portion 301 is an electrode portion having a function of dispersing current in the second semiconductor layer 104. Therefore, when the cross-sectional area is reduced, the resistance is increased and the current dispersion function cannot be performed. Al, Ag, Au, Pt, Cu, Ti, Ni, and the like are metals having a sufficiently low resistance to be used for current dispersion of the light emitting element, but have a limited cross-sectional area.
Therefore, it is preferable to provide a cross-sectional area of 0.1 μm ² or more. For example, in this embodiment, when the second conductivity type is n-type, a Ti layer of 100 nm, an AuGe alloy layer of 50 nm, and an Au layer of 100 nm are stacked on the second semiconductor layer 104 by vapor deposition.
The Au layer may be Ag, Al, Pt, or Cu, and the Ti layer may be omitted or replaced with Ni. Further, the stacking order is not limited to the order presented in the present embodiment. Further, the film thickness is not limited to this example, and can be freely selected within the range of a cross-sectional area of 0.1 μm ² or more. Therefore, if the width of the thin wire electrode 301 is increased, it can be made thinner than this example. Needless to say, if it becomes narrower, it can be made thicker than this example.

In the present embodiment, an AuGe alloy is used as the dopant source Ge. This is because the alloy is easier to handle in the vapor deposition method.
For example, in the case of forming by a method other than the vapor deposition method, such as a sputtering method, a MOVPE (metal organic chemical vapor deposition) method, or an MBE (molecular beam epitaxy) method, only Ge may be used. The same applies to S, Se, and Si.
When the second conductivity type is p-type, the AuGe alloy layer in the previous example may be replaced with an alloy layer such as AuZn. Even if the second conductivity type is p-type, the stacking order is not limited to the previous example, and various orders can be selected.

As shown in FIG. 3, the pad electrode portion 303 is formed so as to have a region 302 that overlaps with the thin wire electrode portion 301.
The pad electrode portion 303 is formed of a metal including at least one of Al, Ag, Au, Pt, Cu, Ti, and Ni.
When the second conductivity type is p-type, the pad electrode portion 303 has one or more kinds of metals of S, Se, Si, and Ge (that is, a metal that becomes an n-type dopant with respect to the second semiconductor layer 104). Or does not contain any metal of Be, Zn, Mg, C, S, Se, Si, or Ge (that is, a metal that becomes a p-type dopant for the second semiconductor layer 104 is also an n-type dopant). (Not including the metal to be formed).
When the second conductivity type is n-type, the pad electrode portion 303 is made of at least one of Be, Zn, Mg, and C (that is, a metal that becomes a p-type dopant with respect to the second semiconductor layer 104). Or any metal of Be, Zn, Mg, C, S, Se, Si, and Ge is not included (that is, the metal serving as the p-type dopant for the second semiconductor layer 104 is also n-type). (The metal which does not contain a dopant is not included).

In the present embodiment, a Ti layer of 100 nm and an Au layer of 900 nm are stacked on the second semiconductor layer 104 as the pad electrode portion 303. The Au layer may be Ag, Al, Pt, or Cu, and the Ti layer may be omitted or replaced with Ni.
In this example, the Ti layer is a single layer above the Ti layer, but various combinations of structures such as a structure in which Al and Au are laminated or a structure in which Ag and Au are laminated can be selected.
Further, in this example, the thickness of the pad electrode portion 303 is 1000 nm. However, since it is sufficient to provide a thickness that can absorb an impact at the time of wire bonding, the thickness is not limited to this example, and may be thin. . The thicker the thickness, the higher the shock absorbing power at the time of wire bonding. However, since this increases the cost, it is not a preferable design to increase the thickness excessively, and it is preferable to suppress the thickness to about 3000 nm.
Further, it is preferable that the thickness of the pad electrode portion 303 is 200 nm or more thicker than that of the thin wire electrode portion 301. Thus, the thickness which can absorb the impact at the time of wire bonding is securable by making the thickness of the pad electrode part 303 200 nm or more thicker than the thin wire | line electrode part 301.
The width of the electrode (overlapping region 302) at the boundary between the pad electrode portion 303 and the thin wire electrode portion is preferably 5 μm or more. Thus, by setting the width of the electrode at the boundary between the pad electrode portion and the fine wire electrode portion to 5 μm or more, the pad electrode portion and the fine wire electrode portion can be electrically connected with a low resistance.

Heat treatment is performed in a state where the fine wire electrode portion 301 and the pad electrode portion 303 are formed. By this heat treatment, an alloy layer is formed on the semiconductor layer in contact with the metal. Since mutual diffusion occurs from the metal layer to the semiconductor layer and from the semiconductor layer to the metal layer when forming the alloy layer, a mechanically strong layer is formed.
Peeling phenomenon of the electrode part at the time of wire bonding occurs at the interface between the layers, but a layer whose composition changes continuously through the alloy layer is formed between the metal of the electrode part and the semiconductor layer by heat treatment. Since the interface does not exist, it is possible to prevent the electrode portion from peeling from the semiconductor layer during wire bonding.

  When the second conductivity type is p-type and the pad electrode portion 303 contains one or more dopant metals of S, Se, Si, and Ge, the resistance of the semiconductor even if the dopant metal diffuses into the semiconductor layer by heat treatment Rather, it acts as an effect of increasing the resistance of the semiconductor layer by compensating the p-type dopant. As a result, the resistance with the semiconductor layer in contact with the pad electrode portion 303 becomes very large.

  When the second conductivity type is n-type and the pad electrode portion 303 includes one or more dopant metals of Be, Zn, Mg, and C, the resistance of the semiconductor even if the dopant metal diffuses into the semiconductor layer by heat treatment Rather, it acts as an effect of increasing the resistance of the semiconductor layer by compensating the n-type dopant. As a result, the resistance with the semiconductor layer in contact with the pad electrode portion 303 becomes very large.

  When the pad electrode portion 303 is formed with a structure that does not include any of the doped metals Be, Zn, Mg, C, S, Se, Si, and Ge, the dopant metal does not diffuse into the semiconductor layer due to the heat treatment, so the semiconductor layer side The resistance does not decrease. Therefore, the resistance with the semiconductor layer in contact with the pad electrode portion 303 is increased.

  As described above, it is possible to realize the light emitting element 121 having a structure in which current selectively flows through the thin wire electrode portion 301 and current does not flow through the pad electrode portion 303 or is extremely difficult to flow.

Next, a second embodiment will be described with reference to FIGS. 5, 6, 7, and 8.
FIG. 5 is a cross-sectional view of an epitaxial wafer used for manufacturing the light emitting device of the second embodiment of the present invention.
FIG. 6 is a process cross-sectional view illustrating a manufacturing process of the light emitting device according to the second embodiment of the present invention.
FIG. 7 is a schematic cross-sectional view of a light emitting device according to the second embodiment of the present invention.
FIG. 8 is a top view (a plan view seen from the second semiconductor layer side) of the light emitting device according to the second embodiment of the present invention.
As shown in FIG. 5, the epitaxial wafer 500 is formed with a buffer layer 502 and an etching stop layer 503 on a starting substrate 501, and then a second conductivity type second semiconductor layer 504, an active layer 505, a first conductivity type. The light emitting portion 520 is formed by stacking the first semiconductor layers 506.
For example, when the starting substrate 501 is GaAs, the material of the light emitting part is (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ _1, 0, 35 ≦ y ≦ 0.65), Al _z Ga. _1-z As (0 ≦ z ≦ 1) or (Al _x Ga _1-x ) _y In _1-y N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1) can be selected.
When the starting substrate 501 is Ge or ZnO, the buffer layer 502 is a layer including an effect of adjusting the lattice mismatch.
The active layer 505 is adjusted to a composition having a smaller band gap than the first semiconductor layer 506 and the second semiconductor layer 504 in order to produce a carrier confinement effect.
Furthermore, although it is preferable to form the contact layer 507 over the light-emitting portion 520 because contact resistance with the metal electrode formed thereabove is reduced, it is not necessarily provided.
When the contact layer 507 is provided, it is preferably provided with a doping concentration of 3 × 10 ¹⁸ / cm ³ or more in order to form an ohmic with the electrode, but in particular, it has a doping concentration of 6 × 10 ¹⁸ / cm ³ or more. Is preferred.

The second semiconductor layer 504 is effectively provided with a region having two or more kinds of doping concentrations in order to enhance the current dispersion effect. A layer in which the doping concentration of one layer is more than twice the doping concentration of the other layer is arranged in two or more layers from the region on the starting substrate 501 side of the second semiconductor 504 to the direction in contact with the active layer 505. Is preferred.
The current is dispersed in the lateral direction at the interface between the low-concentration doping layer and the high-concentration doping layer, and the current flows with low resistance in the high-concentration doping layer, so that effective current dispersion is realized even in a thin film.
When a plurality of pairs of the low-concentration doping layer and the high-concentration doping layer are combined, the effect of current dispersion can be further enhanced.
The effect of current dispersion is remarkable in the region where the doping concentration of the low-concentration doping layer is 3 × 10 ¹⁷ / cm ³ or less and the doping concentration of the high-concentration doping layer is 6 × 10 ¹⁷ / cm 3. ^Three or more areas.
The effect of current dispersion is an effect due to a difference in doping concentration, and the low-concentration doping layer only needs to have a thickness of 50 nm or more when the epitaxial layer is formed.
Even if the low concentration doping layer is higher than 3 × 10 ¹⁷ / cm ³ and the high concentration doping layer is less than 6 × 10 ¹⁷ / cm ³ , two or more pairs of the low concentration doping layer and the high concentration doping layer can be provided. In this case, since the film thickness is increased, the cost can be increased, but the same effect can be obtained.

As shown in FIG. 6A, a dielectric film 601 is provided on the contact layer 507 after the contact layer 507 is formed. The dielectric film 601 can be selected from silicon oxide, silicon nitride, gallium oxide, sapphire, and the like. However, when pattern formation is performed by wet etching, the etching can be easily performed by selecting a silicon oxide film or a silicon nitride film.
When pattern formation is performed by dry etching, all the above materials can be selected.
In the present embodiment, the case of a silicon oxide film is illustrated, but the same effect can be obtained even if the other material is selected.

After forming the dielectric film 601, a part of the dielectric film 601 is opened to form an opening 602. An interface electrode 603 is formed in the opening 602 using a metal containing one or more of Al, Ag, Au, Pt, Cu, Ti, and Ni.
Thereafter, a first bonding metal layer 604 is formed so as to cover the interface electrode 603 formed in the dielectric 601 and the opening 602, and the light emitting substrate 610 is obtained.
The first bonding metal layer 604 is formed of a metal including at least one of Al, Ag, Au, Pt, Cu, Ti, and Ni. However, the first bonding metal layer 604 may have a laminated structure in which a plurality of the above metals are combined. It is good also as a layer of.

Next, as shown in FIG. 6B, a second bonding metal layer 621 is formed on the support substrate 620 to form a base substrate 630.
Note that any material can be selected for the support substrate 620 as long as it has a low electric resistance and is a flat substrate, and can be selected from Si, Ge, GaAs, and InP semiconductors that are opaque to the emission wavelength.
The second bonding metal layer 621 is formed of a metal containing one or more of Al, Ag, Au, Pt, Cu, Ti, and Ni, but may have a laminated structure in which a plurality of the above metals are combined. It is good also as a single layer.

Next, as shown in FIG. 6C, the light emitting substrate 610 and the base substrate 630 are bonded with the first bonding metal layer 604 and the second bonding metal layer 621 facing each other.
In joining, the first joining metal layer 604 and the second joining metal layer 621 are joined by applying a pressure of 1000 N or more and applying heat of 150 ° C. or more, and the light emitting substrate 610 and the base substrate 630 are joined.

After bonding, the starting substrate 501 and the buffer layer 502 are removed. For example, when the starting substrate 501 is GaAs, it is removed with a mixed solution of ammonia and hydrogen peroxide. When the etching stopper layer 503 is, for example, an AlInP layer, the etching stops at the etching stopper layer 503 due to the selectivity of etching in the above-described mixed solution.
After removing the starting substrate 501 and the buffer layer 502, the etching stop layer 503 is removed, and the second semiconductor layer 504 is exposed. The etching prevention layer 503 can be selectively removed by using, for example, an SPM (sulfuric acid / hydrogen peroxide) solution.

Next, as shown in FIGS. 7 and 8, on the exposed second semiconductor layer 504, one layer made of a metal containing at least one of Al, Ag, Au, Pt, Cu, Ti, and Ni. The thin wire electrode portion 701 having the above structure is formed.
When the second conductivity type (conductivity type of the second semiconductor layer 504) is p-type, the thin wire electrode portion 701 has one or more kinds of metals of Be, Zn, Mg, and C (that is, with respect to the second semiconductor layer 504). Metal that becomes a p-type dopant).
When the second conductivity type is n-type, the thin wire electrode portion 701 includes one or more kinds of metals of S, Se, Si, and Ge (that is, a metal that becomes an n-type dopant with respect to the second semiconductor layer 504). .

The thin wire electrode portion 701 is an electrode portion having a function of dispersing current in the second semiconductor layer 504. Therefore, when the cross-sectional area is reduced, the resistance is increased and the current distribution function cannot be performed. Al, Ag, Au, Pt, Cu, Ti, Ni, and the like are metals having a sufficiently low resistance to be used for current dispersion of the light emitting element, but have a limited cross-sectional area.
Therefore, it is preferable to provide a cross-sectional area of 0.1 μm ² or more. For example, in this embodiment, when the second conductivity type is n-type, a Ti layer 100 nm, an AuGe alloy layer 50 nm, and an Au layer 100 nm are stacked on the second semiconductor layer 504 by a vapor deposition method.
The Au layer may be Ag, Al, Pt, or Cu, and the Ti layer may be omitted or replaced with Ni. Further, the stacking order is not limited to the order presented in the present embodiment. Further, the film thickness is not limited to this example, and can be freely selected within a range of a cross-sectional area of 0.1 μm ² or more. Therefore, if the width of the thin wire electrode 701 becomes wider, it can be made thinner than this example. Needless to say, if it becomes narrower, it can be made thicker than this example.

  In the present embodiment, an AuGe alloy is used as the dopant source Ge. This is because the alloy is easier to handle in the vapor deposition method. For example, when forming by a method other than the vapor deposition method such as a sputtering method, a MOVPE method, or an MBE method, only Ge may be used. The same applies to S, Se, and Si.

  When the second conductivity type is p-type, the AuGe alloy layer in the previous example may be replaced with an alloy layer such as AuZn. Even if the second conductivity type is p-type, the stacking order is not limited to the previous example, and various orders can be selected.

As shown in FIG. 8, after forming a metal electrode on the second semiconductor layer 504, a pad electrode portion 703 is formed so as to have a region 702 that overlaps with the thin wire electrode portion 701. The pad electrode portion 703 is formed of a metal including at least one of Al, Ag, Au, Pt, Cu, Ti, and Ni.
When the second conductivity type is p-type, the pad electrode portion 703 has one or more kinds of metals of S, Se, Si, and Ge (that is, a metal that becomes an n-type dopant for the second semiconductor layer 504). Or a structure that does not include any metal of Be, Zn, Mg, C, S, Se, Si, and Ge (that is, does not include a metal serving as a dopant with respect to the second semiconductor layer 504). To do. When the second conductivity type is n-type, the pad electrode portion 703 has one or more kinds of metals of Be, Zn, Mg, and C (that is, a metal that becomes a p-type dopant with respect to the second semiconductor layer 504). Or a structure that does not contain any metal of Be, Zn, Mg, C, S, Se, Si, and Ge.

In the present embodiment, a Ti layer 100 nm and an Au layer 900 nm are stacked on the second semiconductor layer 504 as the pad electrode portion 703. The Au layer may be Ag, Al, Pt, or Cu, and the Ti layer may be omitted or replaced with Ni.
In this example, the Ti layer is a single layer above the Ti layer, but various combinations of structures such as a structure in which Al and Au are laminated or a structure in which Ag and Au are laminated can be selected.
Further, in this example, the thickness of the pad electrode portion 703 is set to 1000 nm. However, it is only necessary to provide a thickness that can absorb an impact at the time of wire bonding. . The thicker the thickness, the higher the shock absorbing power at the time of wire bonding. However, since this increases the cost, it is not a preferable design to increase the thickness excessively, and it is preferable to suppress the thickness to about 3000 nm.

  Next, as shown in FIG. 7, a back metal electrode 705 is formed on the lower surface of the support substrate 620. Thereafter, heat treatment is performed in a state where the thin wire electrode portion 701, the pad electrode portion 703, and the back surface metal electrode 705 are formed. By this heat treatment, an alloy layer is formed on the semiconductor layer in contact with the metal electrode. Since mutual diffusion occurs from the metal layer to the semiconductor layer and from the semiconductor layer to the metal layer when forming the alloy layer, a mechanically strong layer is formed. Peeling phenomenon of the electrode part at the time of wire bonding occurs at the interface between the layers, but a layer whose composition changes continuously through the alloy layer is formed between the metal of the electrode part and the semiconductor layer by heat treatment. Since the interface does not exist, it is possible to prevent the electrode portion from peeling from the semiconductor layer during wire bonding.

  When the second conductivity type is p-type and the pad electrode portion 703 includes one or more kinds of dopant metals of S, Se, Si, and Ge, even if the dopant metal diffuses into the semiconductor layer by heat treatment, It acts as an effect of increasing the resistance of the semiconductor layer by compensating the p-type dopant without lowering the resistance. As a result, the resistance with the semiconductor layer in contact with the pad electrode portion 703 becomes very large.

  When the second conductivity type is n-type and the pad electrode portion 703 contains one or more dopant metals of Be, Zn, Mg, and C, the resistance of the semiconductor even if the dopant metal diffuses into the semiconductor layer by heat treatment Rather, it acts as an effect of increasing the resistance of the semiconductor layer by compensating the n-type dopant. As a result, the resistance with the semiconductor layer in contact with the pad electrode portion 703 becomes very large.

  When the pad electrode portion 703 is formed with a structure that does not include any of the doped metals Be, Zn, Mg, C, S, Se, Si, and Ge, the dopant metal does not diffuse into the semiconductor layer due to the heat treatment. The resistance does not decrease. Therefore, the resistance with the semiconductor layer in contact with the pad electrode portion 703 is increased.

  The spine electrode portion 704 that electrically connects the pad electrode portion 703 and the thin wire electrode portion 701 can have the same configuration as the pad electrode portion 703.

When the second conductivity type is p-type and the pad electrode portion 703 contains a dopant metal such as S, Se, Si, Ge, the region 702 includes the dopant metals Be, Zn, Mg, C contained in the thin wire electrode portion 701. This is a region that includes both one or more kinds of metals and one or more kinds of metals of S, Se, Si, and Ge contained in the pad electrode portion 703.
When the second conductivity type is n-type and the pad electrode portion 703 includes a dopant metal such as Be, Zn, Mg, C, the region 702 includes the dopant metals S, Se, Si, Ge included in the thin wire electrode portion 701. This is a region that includes one or more kinds of metals and any one or more kinds of metals of Be, Zn, Mg, and C contained in the pad electrode portion 703.
In order to realize ohmic contact, a dopant metal having a certain concentration or more is required. Therefore, the contact resistance between the region 702 compensated with the p-type dopant and the n-type dopant and the semiconductor layer is a fine wire electrode even when heat treatment is performed. The resistance becomes higher than the contact resistance between the portion 701 and the semiconductor layer.

  When the pad electrode portion 703 is formed without containing the dopant metal, the region 702 is a region where the dopant metal concentration is thinner than that of the thin wire electrode portion 701. In order to realize ohmic contact, a dopant metal having a certain concentration or more is necessary. Therefore, due to insufficient doping concentration, the contact resistance between the region 702 and the semiconductor layer is reduced even if heat treatment is performed. The contact resistance is higher than

  Accordingly, it is possible to realize the light emitting element 521 having a structure in which a current selectively flows through the thin wire electrode portion 701 excluding the overlapping region 702 and a current does not flow through the pad electrode portion 703 or becomes extremely difficult to flow.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not limited to these.

Example 1
The light emitting device 121 of the first embodiment having the structure shown in FIG. 2 was manufactured by changing the pad diameter of the pad electrode portion 303 in the range of 70 μm to 100 μm.

(Example 2)
The light emitting element 521 of the second embodiment having the structure shown in FIG. 7 was manufactured by changing the pad diameter of the pad electrode portion 703 in the range of 70 μm to 100 μm.

(Comparative Example 1)
A light emitting device was manufactured in the same manner as in Example 1. However, in Comparative Example 1, as shown in FIG. 9, the thin wire electrode portion 201 and the pad electrode portion 203 have a structure having the same type of dopant metal.
That is, when the second conductivity type is p-type, the thin wire electrode portion 201 and the pad electrode portion 203 are one or more layers made of a metal including at least one of Al, Ag, Au, Pt, Cu, Ti, and Ni. It was comprised by the structure, and was made to contain any one or more types of metals of Be, Zn, Mg, and C.
When the second conductivity type is n-type, the thin wire electrode portion 201 and the pad electrode portion 203 have a structure of one or more layers made of a metal including at least one of Al, Ag, Au, Pt, Cu, Ti, and Ni. It is configured to include one or more kinds of metals of S, Se, Si, and Ge.
The merit of Comparative Example 1 is that the number of photolithography steps can be reduced as in Example 1.
Forming the thin wire electrode portion 201 and the pad electrode portion 203 separately is the best because the pad electrode portion can be made thicker. However, forming the thin wire electrode portion 201 and the pad electrode portion 203 at the same time allows only one photolithography. It can also be formed.

(Comparative Example 2)
A light emitting device was manufactured in the same manner as in Example 1. However, in Comparative Example 2, as shown in FIG. 10A, a photolithography process is performed after a layer having a function of a block layer (a function of blocking current) (an epi layer or a deposited layer of SiO ₂ or the like) is formed. And the etching process leaves the block layer 210 only in the region corresponding to the pad electrode portion 203, and then, as shown in FIG. 10B, the thin wire electrode portion 201 and the pad electrode portion 203 are formed in the same manner as in Comparative Example 1. Formed.
In Comparative Example 2, the material cost for forming the block layer, the cost of the photolithography process for forming the pattern of the block layer 210, and the etching cost are necessary.

(Comparative Example 3)
A light emitting device was manufactured in the same manner as in Example 1. However, in Comparative Example 3, as shown in FIG. 11A, a transparent electrode film 211 is laminated on the second semiconductor layer 104, and a layer (hereinafter referred to as a reducing layer) 212 that reduces the transparent conductive film 211 is formed. After the lamination, a reduction layer 212 having a pattern corresponding to the pad electrode portion 203 ′ region is formed by a photolithography process and an etching process, and then, as shown in FIG. A part 201 ′ and a pad electrode part 203 ′ were formed.
Compared with the comparative example 1, the comparative example 3 requires the lamination process of the transparent conductive film 211, the lamination process of the reduction layer 212, the photolithography process for pattern formation, and the etching process. Obviously higher.

  Table 1 shows the number of steps until the formation of the fine wire electrode portion and the pad electrode portion is completed after exposing the second semiconductor layer for Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3. It is.

As can be seen from Table 1, in Comparative Example 1, the number of steps can be designed to be lower than that in Example 1, but Comparative Example 2 and Comparative Example 3 cannot be designed with fewer steps than Example 1.
Therefore, when Comparative Example 2 and Comparative Example 3 are used, it is inevitable that the material cost and the manufacturing cost are higher than those of Example 1.

FIG. 13 shows the light emission outputs of Comparative Example 1, Comparative Example 2, and Comparative Example 3 when the light emission output of Example 1 is 1.
The width of the thin wire electrode portion was 5 μm in all examples, the chip size was rectangular, and one side was 250 μm.
As can be seen from FIG. 13, the light output of Comparative Example 1 is significantly lower than that of Example 1, and even if the area of the pad electrode portion is reduced, it does not become the same level as the light output of Example 1. On the other hand, in Comparative Example 2 and Comparative Example 3, the output is almost the same as that in Example 1.

  The reason why the light emission output is greatly reduced in Comparative Example 1 compared to Example 1 is as follows. That is, in Comparative Example 1, the fine wire electrode portion 201 and the second semiconductor layer 104 are in ohmic contact, and the pad electrode portion 203 and the second semiconductor layer 104 are in ohmic contact. Since the contact resistance per unit area is the same as the contact resistance per unit area between the pad electrode portion 203 and the second semiconductor layer 104, the current concentrates on the pad electrode portion 203 having a relatively large area, and the thin wire electrode The current flowing through the unit 201 is reduced. As a result, only light emission directly under the pad electrode having a large area becomes strong, so that much of the light emitted from the active layer 105 cannot be extracted, and the output of the light emitting element is lowered.

FIG. 13 illustrates a range in which the pad diameter is up to 70 μm, but the pad diameter of 70 μm is merely the most general size in assembly, and the pad diameter is 0 ( It is presumed that this tendency is maintained until a state where no pad electrode exists).
Moreover, it is estimated that the same tendency is maintained even when the pad diameter is 100 μm or more.

  From the above results, it can be seen that in Example 1, it is possible to realize a light emitting element capable of maintaining a light emission output comparable to that of Comparative Example 2 and Comparative Example 3 with a small number of steps, that is, a small manufacturing cost.

(Comparative Example 4)
A light emitting device was manufactured in the same manner as in Example 2. However, in Comparative Example 4, as shown in FIG. 12, the electrode materials of the thin wire electrode portion 801, the pad electrode portion 803, and the spine electrode portion 804 are the same, and all the electrodes are in ohmic contact with the second semiconductor layer 504. I made it.
In FIG. 12, the interface electrode 813 corresponds to the interface electrode 603 in FIG.

  In Comparative Example 4, when the interface electrode 813 is close to the spine electrode portion 804 or the pad electrode portion 803, the current is concentrated on the pad electrode portion 803 or the spine electrode portion 804, and the light emitting portion is concentrated on the pad electrode portion 803 or the spine electrode portion 804. Therefore, it is necessary to make the distance from both larger than the distance from the thin wire electrode portion 801. In this design, since the light emitting layers around the pad electrode portion 803 and the spine electrode portion 804 cannot contribute to light emission, not only the luminance can be gained but also the pn junction area contributing to energization is reduced. Was also the cause of the rise.

  On the other hand, in Example 2, the electrode in the region corresponding to the spine electrode portion 804 of Comparative Example 4 is the spine electrode portion 704, but the spine electrode portion 704 has a high resistance to the semiconductor layer like the pad electrode portion 703. They are in contact with each other, and current does not flow to the region immediately below the pad electrode portion 703 and the spine electrode portion 704. Therefore, even if the interface electrode 603 is close to the spine electrode portion 704 or the pad electrode portion 703, current does not concentrate on the pad electrode portion 703 or the spine electrode portion 704. Therefore, the interface electrode 603 is the interface electrode in the comparative example 4. Since it can be longer than 813 and can be used as a light emitting region up to the vicinity of the pad electrode portion 703 and the spine electrode portion 704, the VF value can be made lower than that of the comparative example 4.

FIG. 14 shows a comparison of light emission output (PO), VF value, and increase rate of light emission efficiency with respect to Comparative Example 4 of Example 2. In FIG. 14, the width of the thin wire electrode portion is 5 μm, the chip size is rectangular, and one side is 250 μm. It is estimated that the same tendency is exhibited even if the chip size and the width of the thin wire electrode are different.
As can be seen from FIG. 14, in the comparison of the light emission output (PO) between Example 2 and Comparative Example 4, since Example 2 is not accompanied by a change in internal quantum efficiency as compared with Comparative Example 4, there is a large difference. Is not seen.
On the other hand, in the comparison of the VF values between Example 2 and Comparative Example 4, Example 2 is 10% or more lower than Comparative Example 4.
The reason for the decrease in the VF value is that in Example 2, the region contributing to light emission, in other words, the region in which current flows increased compared to Comparative Example 4, so that the current density decreased and the VF value decreased. it can.
As a result, as shown in the luminous efficiency change rate curve of FIG.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

100: Epitaxial wafer 101: Starting substrate 102: Buffer layer
103 ... Etching prevention layer, 104 ... Second semiconductor layer, 105 ... Active layer,
106: First semiconductor layer, 107: Composition adjusting layer, 108: Window layer,
120 ... light emitting part, 121 ... light emitting element,
201, 201 '... fine wire electrode part, 203, 203' ... pad electrode part,
210: Block layer, 211: Transparent conductive film, 212: Reduction layer 301 ... Fine wire electrode part, 302 ... Overlapping region, 303 ... Pad electrode part,
401 ... dot electrode,
500 ... Epitaxial wafer, 501 ... Starting substrate, 502 ... Buffer layer,
503 ... Etching stop layer, 504 ... Second semiconductor layer, 505 ... Active layer,
506: First semiconductor layer, 507: Contact layer, 520: Light emitting part,
521 ... Light emitting element,
601 ... Dielectric layer, 602 ... Opening, 603 ... Interface electrode, 610 ... Light emitting substrate,
620 ... support substrate, 621 ... second bonding metal layer, 630 ... pedestal substrate interface electrode,
701 ... Fine wire electrode part, 702 ... Overlapping region, 703 ... Pad electrode part,
704 ... spine electrode part, 705 ... back metal electrode,
801 ... Fine wire electrode part, 803 ... Pad electrode part, 804 ... Spine electrode part.

Claims (9)

A light emitting portion in which at least a first semiconductor layer having the first conductivity type, an active layer, and a second semiconductor layer having the second conductivity type are formed in this order, a pad electrode portion in contact with the second semiconductor layer, and the second A light-emitting element having a first electrode portion that is in contact with the semiconductor layer and has a fine wire electrode portion that is connected to the pad electrode portion, and a second electrode portion provided on the first semiconductor layer side,
When the second semiconductor layer is n-type,
The pad electrode portions Al, Ag, Au, Pt, Cu, Ti, consists of one or more layers structure containing any one or more metals of Ni, the pad electrode portion over the previous SL second semiconductor layer Including one or more kinds of metals as p-type dopants as dopant metals,
The fine wire electrode portion is composed of one or more layers including one or more metals of Al, Ag, Au, Pt, Cu, Ti, and Ni, and the fine wire electrode portion is formed with respect to the second semiconductor layer. including one or more metals as n-type dopants as dopant metals,
When the second semiconductor layer is p-type,
The pad electrode portion, Al, Ag, Au, Pt , Cu, Ti, consist one or more layers structure containing any one or more metals of Ni, the pad electrode portion prior Symbol second semiconductor layer On the other hand, it contains one or more kinds of metals as n-type dopants as dopant metals,
The fine wire electrode portion is composed of one or more layers including one or more metals of Al, Ag, Au, Pt, Cu, Ti, and Ni, and the fine wire electrode portion is formed with respect to the second semiconductor layer. A light-emitting element including one or more kinds of metals serving as a p-type dopant as a dopant metal.   2. The light emitting device according to claim 1, wherein a window layer having a thickness of 10 μm or more is formed on a side of the first semiconductor layer opposite to the active layer.   The light emitting device according to claim 2, further comprising a composition adjustment layer between the first semiconductor layer and the window layer. A support substrate having the second electrode portion on the lower surface;
A bonding metal layer provided on the support substrate and functioning as a reflective layer;
A dielectric layer provided between the bonding metal layer and the first semiconductor layer;
2. The light emitting device according to claim 1, further comprising an interface electrode penetrating a part of the dielectric layer and in contact with the bonding metal layer and the first semiconductor layer. The second semiconductor layer is made of an AlGaInP-based compound semiconductor, an AlGaInN-based compound semiconductor, or an AlGaAs-based compound semiconductor,
The metal serving as a p-type dopant for the second semiconductor layer is any one of Be, Zn, Mg, and C.
5. The light emitting device according to claim 1, wherein the metal that is an n-type dopant for the second semiconductor layer is any one of S, Se, Si, and Ge. . The pad electrode part has a thickness of 200 nm or more than the thin wire electrode part,
The light emitting element according to claim 1, wherein a width of an electrode at a boundary portion between the pad electrode portion and the thin wire electrode portion is 5 μm or more. The active layer is made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.35 ≦ y ≦ 0.65);
The first semiconductor layer and the second semiconductor layer are made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.35 ≦ y ≦ 0.65). Item 7. The light emitting device according to any one of Items 1 to 6. The active layer is made of (Al _x Ga _1-x ) _y In _1-y N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1),
Claims 1 to 6, characterized in that said first semiconductor layer and the second semiconductor layer is made of _{(Al x Ga 1-x)} y In 1-y N (0 ≦ x ≦ 1,0 ≦ y ≦ 1) The light emitting element as described in any one of these. The active layer is made of (Al _x Ga _1-x ) As (0 ≦ x ≦ 1),
The first semiconductor layer and the second semiconductor layer are (Al _x Ga _1-x ) As (0 ≦ x ≦ 1) or (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0 The light-emitting element according to claim 1, wherein the light-emitting element is formed of .35 ≦ y ≦ 0.65).

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