JP2003110142A - Oxide semiconductor light-emitting device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device which exhibits excellent electrical and light-emitting properties and to provide its manufacturing method. SOLUTION: A ZnO light-emitting diode 100 is provided with a p-ZnO layer 103 and a p-type ohmic electrode 105 which is formed on the p-ZnO layer 103. The p-type ohmic electrode 105 is made of Ni.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an oxide semiconductor light emitting device and a method for manufacturing the same.

[0002]

2. Description of the Related Art ZnO (zinc oxide) is a direct transition type semiconductor having a bandgap (about 3.2 eV) corresponding to the ultraviolet region, its exciton binding energy is as high as 60 meV, and exciton emission is high even at room temperature. To be observed,
By utilizing this, a light emitting device having higher efficiency and lower power consumption than GaN (gallium nitride) and ZnSe (zinc selenide) which are currently put into practical use can be realized.

Conventionally, it has been difficult to control the p-type conductivity of ZnO, but a technique for obtaining low resistance p-ZnO by the simultaneous doping method invented by Yamamoto et al.
It is disclosed in Japanese Patent No. 48698.

Further, Xin-Li, Guo et al. Produced a ZnO homojunction light-emitting diode by applying p-ZnO doped with acceptor using N ₂ O plasma (Jpn.J.Appl.Phys. Vol.40 (2001) p
p.L177). Here, Xin-Li, Guo et al.
Au (gold) is used as the ZnO electrode.

[0005]

However, the device resistance of the above-mentioned light emitting diode is as high as 15 kΩ or more, and most of them are contacts of Au electrode / p-ZnO layer considering the electrical characteristics of ZnO shown in the literature. It is resistance.

Further, the Au electrode directly formed on the ZnO layer by the electron beam evaporation method or the like has poor compatibility with ZnO and is easily peeled off in a step such as wire bonding. The same applies to metals such as Pt (platinum) and Pd (palladium) which have a large work function and are considered to be suitable as an electrode material for the wide-gap p-type semiconductor layer.

That is, a p-ZnO ohmic electrode having excellent practicability has not been invented yet.

[0008] Therefore, an object of the present invention is to provide an ohmic electrode material suitable for a p-type oxide semiconductor layer, and to provide a light emitting device having excellent electric and light emitting characteristics and a method for manufacturing the same.

[0009]

In order to solve the above problems, an oxide semiconductor light emitting device of the present invention is in contact with a p-type oxide semiconductor layer containing at least Zn as a host element and the p-type oxide semiconductor layer. And a p-type electrode provided as described above, wherein the p-type electrode is composed of a metal thin film containing at least one selected from the group consisting of Ni (nickel), Co (cobalt) and Cu (copper). Is characterized by.

According to the oxide semiconductor light emitting device having the above structure, Ni, Co and Cu easily form an oxide, and the conductivity type of the oxide is p-type. Therefore, a p-type oxide semiconductor layer containing at least Zn as a host element,
For example, when these metals are formed on the surface of the ZnO layer, the metal diffused into the ZnO layer from the interface forms a p-type oxide intermediate layer, and thus low ohmic characteristics with respect to the p-type oxide semiconductor are obtained. . As a result, the contact resistance between the p-type oxide semiconductor and the p-type electrode is reduced, and the electric / light emitting characteristics can be improved.

Further, since the p-type oxide intermediate layer is an oxide, it has good compatibility with the ZnO layer and is excellent in adhesiveness as compared with an electrode material such as Au, Pt, or Pd which does not form an oxide.

In the oxide semiconductor light emitting device of one embodiment, the p-type electrode has a thickness of 100 Å or more.

The oxide semiconductor light emitting device of the above embodiment is
When the thickness of the p-type electrode is 100 Å or more, the p-type electrode is not peeled off in a process such as wire bonding, and low resistance ohmic characteristics are provided between the p-type oxide semiconductor and the p-type electrode. can get.

In the oxide semiconductor light emitting device of one embodiment, the p-type electrode has a thickness of 500 Å or less.

The oxide semiconductor light emitting device of the above embodiment is
Since the thickness of the p-type electrode is 500 Å or less,
Since the p-type electrode has sufficient translucency for light emission from the p-type oxide semiconductor layer, the efficiency of light extraction via the p-type electrode is excellent.

In this specification, the light-transmitting property means that the light from the p-type oxide semiconductor layer passes through the p-type electrode, and does not necessarily mean colorless and transparent.

By the way, with respect to Ni, Co and Cu, the p-type ohmic electrode having a low resistance is formed only by directly forming it on the p-type oxide semiconductor layer by the above-mentioned action, but Au or Au as a wire bonding pad is formed. Even when it is desired to form a metal layer such as Al (aluminum) on the outermost surface of the electrode, by forming a contact layer in ohmic contact with the p-type semiconductor layer between the metal layer and the p-type oxide semiconductor layer, Resistive ohmic characteristics can be obtained.

In view of the above, the oxide semiconductor light emitting device of the present invention has p containing at least Zn as a host element.
Type oxide semiconductor layer and a p-type electrode provided so as to be in contact with the p-type oxide semiconductor layer, the p-type electrode being in contact with the p-type oxide semiconductor layer,
And a metal layer formed on this contact layer,
The contact layer contains at least one selected from the group consisting of Ni, Co and Cu.

In the oxide semiconductor light emitting device of one embodiment, the contact layer is an oxide layer.

According to the oxide semiconductor light emitting device of the above embodiment, an oxide layer such as NiO, CoO and Cu _x O is formed on the p-type oxide semiconductor layer, and a pad electrode is formed on the oxide layer. It is preferable to form the metal layer because the p-type contact layer can be formed thicker.

The oxide semiconductor light-emitting device of one embodiment, the contact layer is _{Cu x M y O 2 (x} , y = 1 or 2) and has a composed molecular structure, the element of the M is A
1, at least one element selected from the group consisting of Ga (gallium), In (indium), Sc (scandium) and Sr (strontium).

According to the oxide semiconductor light emitting device of the above embodiment
Then, Cu among Cu oxides_xM _yO_Two(X, y = 1
Alternatively, the compound having the molecular structure of 2) is Cu d
The orbital energy level is almost the same as the 2p orbital energy of oxygen
Since they are the same, they form a hybrid orbit and show p-type conduction.

In particular, the element of M is Al, Ga, I
If at least one of n, Sc and Sr is used, the contact layer is Zn, which is an example of the material of the p-type oxide semiconductor layer.
It is preferable because it has a band gap similar to that of O and exhibits low-resistance p-type conduction.

In the oxide semiconductor light emitting device of one embodiment, the contact layer has a thickness of 10 Å or more and 100 Å or less, and the metal layer has a thickness of 100 Å or more and 500 Å or less.

According to the oxide semiconductor light emitting device of the above embodiment, the thickness of the contact layer is set in the range of 10Å to 100Å, and the metal layer formed on the contact layer is set to 100Å to 500Å. Thus, a p-type electrode having low resistance, high adhesion and translucency can be obtained.

In the method for manufacturing an oxide semiconductor light emitting device of the present invention, at least one selected from the group consisting of Ni, Co and Cu is contained on the p-type oxide semiconductor layer containing at least Zn as a host element. It is characterized in that a metal thin film is deposited in an oxygen atmosphere to form the metal thin film as a p-type ohmic electrode.

According to the method for manufacturing an oxide semiconductor light emitting device having the above structure, the p-type ohmic electrode containing at least one of Ni, Co and Cu is formed by resistance heating, electron beam evaporation, sputtering, Although there is a pulse laser deposition method or the like, by depositing at least one metal of Ni, Co and Cu in an oxygen atmosphere, formation of a p-type oxide intermediate layer in the p-type oxide semiconductor layer is promoted, An oxide semiconductor light emitting device having a p-type ohmic electrode having low resistance and excellent adhesion can be manufactured.

In particular, heat treatment is applied to the metal thin film and the p-type oxide semiconductor layer during the deposition of the metal thin film, so that p
It is preferable because diffusion and oxidation of the metal into the type oxide semiconductor layer are promoted. As the temperature of the heat treatment at this time,
From the viewpoint of promoting the diffusion and oxidation of the metal into the p-type oxide semiconductor layer, it is preferably 300 degrees or more. The temperature of the heat treatment is preferably 500 ° C. or less from the viewpoint of suppressing the introduction of defects due to excessive diffusion of metal into the p-type oxide semiconductor layer.

Therefore, in the method for manufacturing an oxide semiconductor light emitting device according to one embodiment, heat treatment is performed at 300 ° C. or more and 500 ° C. or less during the deposition of the metal thin film.

The same effect can be obtained even if such heat treatment is performed after the metal thin film is deposited.

That is, in the method for manufacturing an oxide semiconductor light emitting device of the present invention, p containing at least Zn as a host element is used.
After depositing a metal thin film containing at least one selected from the group consisting of Ni, Co and Cu on the surface of the type oxide semiconductor layer, the metal thin film is heat-treated in an oxygen atmosphere, The metal thin film is a p-type ohmic electrode.

In the method for manufacturing an oxide semiconductor light emitting device of one embodiment, the temperature of the heat treatment is 300 ° C. or more and 500 ° C. or less.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings.

(Embodiment 1) As Embodiment 1 of the present invention, p-Zn of a pn junction light emitting diode using ZnO is used.
An example in which a Ni electrode is applied to the O layer is shown.

FIG. 1 is a schematic sectional view of a ZnO light emitting diode 100 according to the first embodiment of the present invention, and FIG. 2 is a LMBE (laser molecular beam epitaxy) used in the first embodiment.
It is a schematic block diagram of an apparatus. Z using this LMBE device
Crystal growth of nO is performed.

In the LMBE apparatus, the substrate holder 2 is arranged above the growth chamber 1 which can be evacuated to an ultrahigh vacuum, and the substrate 3 is fixed to the substrate holder 2. The substrate heater 2 is arranged above the substrate holder 2 so that the substrate holder 2
Is heated and the substrate 3 is heated by its heat conduction. A target table 5 is arranged immediately below the substrate holder 2 at an appropriate distance, and a plurality of raw material targets 6 can be arranged on the target table 5.

The surface of the raw material target 6 has a growth chamber 1
The raw material of the raw material target 6 laser ablated by the pulsed laser light 8 radiated through the view port 7 provided on the side surface of the substrate, and instantly evaporated, deposits on the substrate 3 to grow a thin film.

The target table 5 has a rotating mechanism, and by controlling the rotation in synchronization with the irradiation sequence of the pulsed laser light 8, it becomes possible to stack different target materials on the thin film.

Further, the growth chamber 1 is provided with an O ₂ gas introduction pipe 10A for supplying O ₂ gas into the growth chamber 1, and an N ₂ gas for supplying N ₂ gas to the N ₂ radical source 9. _{A 2} gas introduction pipe 10B is provided. It is also possible to irradiate the substrate 3 with the atomic beam activated by the N ₂ radical source 9. Note that the reference numeral 11 indicates a plume (a group of emitted particles).

A ZnO single crystal substrate, a sapphire substrate, or the like can be used as the substrate 3 in the ZnO crystal growth using the LMBE apparatus having the above-described structure. In the first embodiment, the ScMgAlO ₄ single crystal substrate was used. .
At this time, ZnO is used as a surface for growing ZnO crystals.
Very small lattice mismatch between O and a-axis (0.09%)
The (0001) plane of the ScMgAlO ₄ single crystal substrate was used.

As the substrate heater 4, Nd:
Using a YAG laser (wavelength 1064 nm), the spot diameter and irradiation position on the back surface of the substrate holder 2 are controlled,
The entire substrate 3 was heated uniformly. Then, during the crystal growth, the oxygen gas was introduced through the O ₂ gas introducing pipe 10A at a pressure of 1 × 10.
^It was introduced into the growth chamber 1 so that the pressure was ⁻⁵ Torr.

A method of manufacturing the ZnO light emitting diode 100 as an example of the oxide semiconductor light emitting device of the present invention will be described below with reference to FIG.

First, Ga as a donor impurity is replaced with Ga ₂ O.
ZnO sintered body with 0.1 at% added in the form of ₃ (purity 9
Laser ablation (wavelength: 248 nm, laser output: 1 J / cm ² , frequency: 10 Hz) targeting 9.99%), and setting the substrate temperature to 600 ° C.,
As shown in FIG. 2, ScMgAlO ₄ single crystal substrate 101
Carrier density on the (0001) plane of 1 × 10 ¹⁸ cm
^-3 n-ZnO layer 102 was grown to 1 μm.

Next, the substrate temperature is lowered to 400 ° C., nitrogen N _{2 serving} as an acceptor impurity is activated by the radical source 9 and the ScMgAlO ₄ single crystal substrate 101 is irradiated, and the ZnO sintered body is ablated and simultaneously doped. With a carrier density of 2 × 10 ¹⁸ cm ⁻³ p-Zn
The O layer was grown to 0.5 μm. At this time, the pressure of N ₂ gas was 2 × 10 ⁻⁵ Torr.

Next, a part of the p-ZnO layer is removed by etching to form p-Z as an example of the p-type oxide semiconductor layer.
When the nO layer 103 is formed, a part of the n-ZnO layer 102 is exposed. Then, the n-type ohmic electrode 104 made of Al is provided on the exposed surface of the n-ZnO layer 102. After that, a p-type ohmic electrode 105 as an example of a p-type electrode is provided on the surface of the p-ZnO layer 103. This p-type ohmic electrode is made of Ni. Also,
Both the n-type ohmic electrode 104 and the p-type ohmic electrode 105 were formed by an electron beam evaporation method at a substrate temperature of 300 ° C. so as to have a thickness of 300 Å. Each of the n-type ohmic electrode 104 and the p-type ohmic electrode 105 thus formed exhibited a light-transmitting property of 60% or more with respect to ultraviolet light of 390 nm.

The ScMgAlO ₄ single crystal substrate 101 on which the ZnO layer and ohmic electrode are formed as described above is cut into a 300 μm square chip and fixed to a lead frame, and the n-type ohmic electrode 104 and the p-type ohmic electrode 105 are formed. After wire bonding, resin sealing was performed to obtain a ZnO light emitting diode 100.

FIG. 3 shows the ZnO light emitting diode 100.
The current-voltage characteristic of is shown. In addition, FIG. 3 also shows, as a comparative example, the characteristics of a ZnO light emitting diode manufactured in the same manner as in Embodiment 1 except that the p-type ohmic electrode 105 is made of Au.

As can be seen from FIG. 3, the forward current is 20 mA.
The operating voltage in is 25 V in the comparative example in which the p-type ohmic electrode made of Au is made of Au, while the operating voltage in Ni is
In the case of the p-type ohmic electrode 105 made of, the voltage was 4V.

FIG. 4 shows the above ZnO light emitting diode 100.
For, the dependence of the operating voltage and the emission intensity on the electrode thickness is shown.

As shown by the solid line in FIG. 4, when the thickness of the p-type ohmic electrode 105 is 100 Å or less, the p-ZnO layer 1 is formed.
The layer thickness of the p-type oxide intermediate layer formed in 03 is not sufficient and the operating voltage increases. Further, as shown by the dotted line in FIG. 4, when the p-type ohmic electrode 105 is 500 Å or more, the translucency of the p-type ohmic electrode is deteriorated, and the emission intensity is remarkably reduced. From this result, it is understood that the thickness of the p-type ohmic electrode 105 is preferably 100Å to 500Å.

In the first embodiment, the p-ZnO layer 103 is used.
Was used as the p-type oxide semiconductor layer, the p-ZnO layer 1
Instead of 03, a p-type oxide semiconductor layer containing at least Zn as a host element may be used.

In the first embodiment, the p-type ohmic electrode 105 made of Ni is used as the electrode of the p-ZnO layer 103. However, the p-type ohmic electrode made of Co is p.
It may be used as an electrode of the —ZnO layer 103. Also in this case, a ZnO light emitting diode was manufactured in the same manner as in the first embodiment, but the current-voltage characteristics were almost the same as those in the first embodiment in FIG.

In place of the p-type ohmic electrode 105, a p-type ohmic electrode made of Cu is used as p-ZnO.
It may be used as an electrode of the layer 103. Also in this case, a ZnO light emitting diode was manufactured in the same manner as in the first embodiment, but the current-voltage characteristics were almost the same as those in the first embodiment in FIG.

In addition, a metal thin film containing at least one selected from the group consisting of Ni, Co and Cu is added to p.
It may be used as a positive ohmic electrode.

(Second Embodiment) In the second embodiment,
A p-type ohmic electrode made of NiO (nickel oxide) was used as the p-type electrode of the p-ZnO layer. As a method for forming the p-type ohmic electrode, an LBME apparatus used for ZnO crystal growth was used, and a NiO sintered body target was laser ablated in an oxygen atmosphere. A ZnO light emitting diode was produced in the same manner as in Embodiment 1 except the above.

According to the above ZnO light emitting diode, the operating voltage at a forward current of 20 mA is 3.8 V, which is lower than that in the first embodiment. The reason for this is p-
It is considered that the p-type oxide intermediate layer having a sufficient thickness was formed at the interface between the ZnO layer and the p-type ohmic electrode made of NiO.

Further, instead of the sintered body of NiO, CoO,
The same results as in the second embodiment were obtained also when the sintered body targets of CuO and Cu ₂ O were used. That is, C
Even when a p-type ohmic electrode made of at least one of oO, CuO, and Cu ₂ O is used as the p-type electrode of the p-ZnO layer, the same effect as that of the second embodiment can be obtained.

(Third Embodiment) In the third embodiment, p
The p-type ohmic electrode used as the p-type electrode of the —ZnO layer is composed of a Ni layer as an example of a contact layer in contact with the p-ZnO layer and an Au layer as an example of a metal layer formed on the Ni layer. Has become. A ZnO light emitting diode was manufactured in the same manner as in the first embodiment except that such a laminated structure of Ni and Au was used, but the current-voltage characteristics are almost the same as those in the second embodiment. Than the case of. This is probably because the Au layer was used as a pad electrode for wire bonding and the contact resistance of the wire lead was sufficiently low.

Further, in the ZnO light emitting diode of the third embodiment, the relationship between the operating voltage and the emission intensity and the thickness of the Ni layer and the Au layer was examined in the same manner as in the first embodiment. As a result, the thickness of the Ni layer is 10Å to 100Å,
Moreover, when the thickness of the Au layer was in the range of 100Å to 500Å, the operating voltage and the emission intensity equivalent to those of the above-described Embodiment 1 could be obtained. Therefore, when a metal layer is formed as a pad electrode on the contact layer in contact with the p-ZnO layer, the thickness of the metal layer is 100Å to 500Å,
Moreover, the thickness of the contact layer such as the Ni layer is set to 10Å to 10
It is understood that the range of 0Å is practically preferable.

In the third embodiment, the p-ZnO layer is made of Ni.
Although the layers are in contact with each other, the layers containing at least one selected from the group consisting of Ni, Co and Cu may be in contact with each other.

(Fourth Embodiment) In the fourth embodiment,
As the p-type electrode of the p-ZnO layer, SrCu_TwoO_TwoLayer and N
Using a p-type ohmic electrode having a laminated structure with an i layer
It was As a method of forming this p-type ohmic electrode, first,
As in the case of the second embodiment, SrCu_TwoO_TwoSintered target
Laser ablation of oxygen in an oxygen atmosphere at 50Å
SrCu_TwoO _TwoForming a layer and forming SrCu_TwoO_TwoAbove
Then, a Ni layer was laminated on. Other than this, it is the same as the first embodiment.
Then, a ZnO light emitting diode was manufactured.

In the above ZnO light emitting diode, the operating voltage at a forward current of 20 mA was 3.2 V, which was lower than in the above-described first to third embodiments.

Instead of the SrCu ₂ O ₂ layer, Cu _x M
_a layer having a molecular structure of _y O ₂ (x, y = 1 or 2) and containing at least one element in which the element of M is selected from the group consisting of Al, Ga, In, Sc and Sr, For example, CuAl ₂ O ₂ layer, CuGa ₂
An O ₂ layer, a CuIn ₂ O ₂ layer, a ScCu ₂ O ₂ layer or the like may be used. This CuAl ₂ O ₂ layer, CuGa ₂ O
_{Even in} a ZnO light emitting diode using _two layers, a CuIn ₂ O ₂ layer, a ScCu ₂ O ₂ layer, etc., the forward current is 20 m.
The operating voltage in A is 3.2 V, which is the same as in the first embodiment.
It is less than the case of ~ 3.

(Fifth Embodiment) In the fifth embodiment,
When the p-type ohmic electrode 105 is formed by vapor deposition on the p-ZnO layer 103 shown in FIG. 1, O is placed in a vapor deposition device (not shown).
₂ Gas 1 × ^{10 -} except introduced at a pressure of 6 Torr is the same as the first embodiment.

According to the ZnO light-emitting diode 100 thus manufactured, the operating voltage at a forward current of 20 mA is 3.3 V, which is lower than that in the first embodiment. It is considered that this is because the diffusion of Ni into the p-ZnO layer 103 was promoted and the p-type conductive oxide intermediate layer was formed with an appropriate thickness.

In addition, p-ZnO is obtained by the method of the first embodiment.
Even if the heat treatment was performed at 300 ° C. in an oxygen atmosphere after forming the Ni electrode 105 on the layer 103, the same result as that of the fifth embodiment was obtained, but when the heat treatment was performed at a temperature of 500 ° C. or higher, the operating voltage was increased. Rose. The reason for this is considered that Ni was excessively diffused into the p-ZnO layer 103 by heat treatment at high temperature, the ohmic characteristics were deteriorated, and the p-ZnO layer had a high resistance. From these results, it is found that the heat treatment temperature during and after the formation of the p-type ohmic electrode made of Ni is preferably 300 ° C to 500 ° C.

Further, the embodiment according to the present invention is not limited to the above-mentioned Embodiments 1 to 5, and the same effect can be obtained for a mixed crystal such as ZnMgO or ZnCdO as an example of a p-type oxide semiconductor. Have.

Even if the structure of the light emitting element is a semiconductor laser diode having an optical resonator and a carrier and light confining mechanism, the effect of the present invention is not impaired.

[0069]

As described above, according to the oxide semiconductor light emitting device of the present invention and the method for manufacturing the same, an ohmic electrode excellent in low resistance, adhesion and translucency can be formed. It is possible to realize an ultraviolet light emitting device having a small size and a long life.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a ZnO light emitting diode according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an LMBE device.

FIG. 3 is a graph showing current-voltage characteristics of the ZnO light emitting diode.

FIG. 4 is a graph showing the electrode thickness dependence of operating voltage and emission intensity of the ZnO light emitting diode.

[Explanation of symbols]

100 ZnO light emitting diode 101 ScMgAlO ₄ single crystal substrate 102 n-ZnO layer 103 p-ZnO layer 104 n-type ohmic electrode 105 p-type ohmic electrode

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hajime Saito             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company F-term (reference) 5F041 AA21 CA41 CA46 CA49 CA55                       CA57 CA67 CA73 CA83 CA84                       CA98

Claims (11)

[Claims] 1. A p containing at least Zn as a host element.
-Type oxide semiconductor layer and a p-type electrode provided so as to be in contact with the p-type oxide semiconductor layer, wherein the p-type electrode is at least one selected from the group consisting of Ni, Co and Cu. An oxide semiconductor light-emitting device comprising a metal thin film containing. 2. The oxide semiconductor light emitting device according to claim 1, wherein the p-type electrode has a thickness of 100 Å or more. 3. The oxide semiconductor light emitting device according to claim 2, wherein the p-type electrode has a thickness of 500 Å or less. 4. A p containing at least Zn as a matrix element.
-Type oxide semiconductor layer and a p-type electrode provided so as to be in contact with the p-type oxide semiconductor layer, the p-type electrode being in contact with the p-type oxide semiconductor layer and the contact And a metal layer formed on the layer, wherein the contact layer contains at least one selected from the group consisting of Ni, Co and Cu. 5. The oxide semiconductor light emitting device according to claim 4, wherein the contact layer is an oxide layer. 6. The oxide semiconductor light-emitting device according to claim 5, said contact layer _{Cu x M y O 2 (x} , y = 1 or 2) and has a composed molecular structure, the element of the M is A
An oxide semiconductor light emitting device comprising at least one element selected from the group consisting of 1, Ga, In, Sc and Sr. 7. The oxide semiconductor light emitting device according to claim 4, wherein the contact layer has a thickness of 10 Å or more and 100 Å or less, and the metal layer has a thickness of 100 Å or more and 500 Å or less. An oxide semiconductor light emitting device characterized by: 8. A p containing at least Zn as a host element.
A metal thin film containing at least one selected from the group consisting of Ni, Co and Cu is deposited on an oxide semiconductor layer in an oxygen atmosphere to form the metal thin film as a p-type ohmic electrode. A method of manufacturing an oxide semiconductor light emitting device having a feature. 9. The method for manufacturing an oxide semiconductor light emitting device according to claim 9, wherein a heat treatment of 300 ° C. or more and 500 ° C. or less is performed during the deposition of the metal thin film. Method. 10. Ni, Co and Cu are formed on the surface of a p-type oxide semiconductor layer containing at least Zn as a matrix element.
After depositing a metal thin film containing at least one selected from the group consisting of, the metal thin film is heat-treated in an oxygen atmosphere, and the metal thin film is used as a p-type ohmic electrode. Method for manufacturing semiconductor light emitting device. 11. The method for manufacturing an oxide semiconductor light emitting device according to claim 11, wherein the temperature of the heat treatment is 300 ° C. or higher and 500 ° C. or lower.