KR100616592B1 - Nitride semiconductor light emitting device having an I-added X-type nitride semiconductor layer - Google Patents

Abstract

The present invention relates to a nitride semiconductor light emitting device that can reduce the operating voltage and leakage current of the light emitting device and at the same time improve the luminance characteristics by adding In when the p-type nitride semiconductor layer is grown. The present invention, a substrate; An n-type nitride semiconductor layer formed on the substrate and doped with an n-type dopant; An active layer formed on the n-type nitride semiconductor layer; A p-type nitride semiconductor layer formed on the active layer and doped with a p-type dopant and including In; And an electrode formed on the n-type nitride semiconductor layer and the p-type nitride semiconductor layer, respectively. According to the present invention, by adding In, the carrier concentration of Mg used as the dopant of the p-type nitride semiconductor layer can be increased. For this reason, the operation voltage of the light emitting element can be lowered by increasing the amount of Mg used as a carrier. In addition, since the amount of deactivated Mg is reduced, the crystallinity of the p-type nitride semiconductor layer is improved, so that the transmittance of the p-type nitride semiconductor layer is improved and the characteristics against reverse voltage and leakage current are improved. This has the effect of improving current spreading.

Nitride semiconductor light emitting device, p-type nitride semiconductor layer, GaN, Mg, In

Description

Nitride semiconductor light emitting device having an indium-doped nitride semiconductor layer TECHNICAL FIELD             

1 is a cross-sectional view of a general nitride semiconductor light emitting device.

Figure 2a is a graph showing the change in XRD half-value width according to the amount of In added in the p-type nitride semiconductor layer according to the present invention.

2B is a graph showing a change in the interval between the peak of the p-type GaN layer and the peak of the sapphire substrate according to the amount of In added in the p-type nitride semiconductor layer according to the present invention.

3 is a graph showing a Raman analysis result according to the In amount of the p-type nitride semiconductor layer according to the present invention.

4 is a graph showing the carrier concentration analysis results according to the In amount of the p-type nitride semiconductor layer according to the present invention.

5A and 5B are graphs comparing current-voltage characteristics of a conventional semiconductor light emitting device and a nitride semiconductor light emitting device according to the present invention.

6 is a graph comparing the transmittance of the conventional p-type nitride semiconductor layer and the transmittance of the In-added p-type nitride semiconductor layer of the present invention.

7 is a graph comparing light output characteristics of a conventional nitride semiconductor light emitting device and a nitride semiconductor light emitting device according to the present invention.

* Description of the symbols for the main parts of the drawings *

11 substrate 11a buffer layer

12 n-type nitride semiconductor layer 13 active layer

14 p-type nitride semiconductor layer 15 transparent electrode layer

16a: n-side bonding electrode 16b: p-side bonding electrode

The present invention relates to a nitride semiconductor light emitting device. More specifically, the present invention relates to a nitride semiconductor light emitting device capable of reducing the operating voltage and leakage current of the light emitting device and simultaneously improving luminance characteristics by adding In when the p-type nitride semiconductor layer is grown.

In recent years, semiconductor light emitting devices, such as light emitting diodes, can generate light in the green, blue, and ultraviolet regions, and are widely applied to fields such as full color display boards and lighting devices as their brightness is dramatically improved due to continuous technological developments. It is becoming. In particular, nitride semiconductors using nitrides such as GaN have been spotlighted as core materials of optoelectronic materials and electronic devices due to their excellent physical and chemical properties.

Such a nitride semiconductor light emitting device is a light emitting device for obtaining light in a blue or green wavelength band, and has an Al _x In _y Ga _(1-xy) N composition formula (where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1, and 0 ≦ x). + y ≤ 1). The nitride semiconductor crystal is grown on a nitride single crystal growth substrate such as a sapphire substrate in consideration of lattice matching. Since the sapphire substrate is an electrically insulating substrate, the final nitride semiconductor light emitting device has a structure in which the p-side electrode and the n-side electrode are formed on the same surface.

1 is a cross-sectional view showing the structure of a general nitride semiconductor light emitting device. In the general nitride semiconductor light emitting device as shown in FIG. 1, a buffer layer 11a, an n-type nitride semiconductor layer 12, an active layer 13, and a p-type nitride semiconductor layer 14 are grown on a substrate 11 in a stacked structure. The electrodes 15, 16a, and 16b are formed on the n-type nitride semiconductor layer 12 and the p-type nitride semiconductor layer 13, respectively, by recombination of holes and electrons injected from the semiconductor layers 12 and 14, respectively. Light is generated in the active layer 13. At this time, the light generated in the active layer 13 is emitted to the transparent electrode layer 15 or the substrate 11 on the p-type nitride semiconductor layer 14. The transparent electrode layer 15 is for forming an ohmic contact as a light transmissive electrode made of a metal thin film or a transparent conductive film formed almost on the entire surface of the p-type nitride semiconductor layer 14.

The nitride semiconductor light emitting device 10 attaches the lower part of the substrate to a lead frame or the like, and the light generated from the active layer 13 emits the light to the outside of the device using the upper surface of the transparent electrode layer 15 as a light emitting surface.

In the conventional nitride semiconductor light emitting device having such a structure, when the p-type nitride semiconductor layer 14 is grown, it is grown mainly using Mg as a dopant. Mg has a significantly lower inductance than Ga, and the p-type nitride semiconductor layer has a large energy bandwidth and a high activation energy of Mg, which leads to a very low activity, thereby greatly reducing the electrical characteristics of the p-type nitride semiconductor layer. That is, since the concentration of Mg acting as a carrier is very low, the operating voltage is increased.

In addition, Mg, which is not activated as a carrier, combines with hydrogen to generate a defect, thereby lowering the crystallinity of the p-type nitride semiconductor layer. Due to the decrease in crystallinity, the leakage current of the device increases, the reverse voltage characteristic deteriorates, the current diffusion is poor, the transmittance of the p-type nitride semiconductor layer decreases, the luminous efficiency of the nitride light emitting device decreases, and the luminance decreases. Problem occurs.

Therefore, in the art, the p-type nitride semiconductor layer is improved by increasing the carrier concentration of Mg used as a dopant in the p-type nitride semiconductor layer of the nitride semiconductor light emitting device, and at the same time reducing defects due to unactivated Mg. There is a need for a technique that can improve crystallinity.

Accordingly, the present invention has been made to solve the above-described problems of the prior art, the object of which is to add the electro-optical characteristics by adding In together with Mg used as a dopant in the growth of the p-type nitride semiconductor layer of the nitride semiconductor light emitting device The present invention provides a nitride semiconductor light emitting device that can be improved.

The present invention as a technical configuration for achieving the above object,

Board;

An n-type nitride semiconductor layer formed on the substrate and doped with an n-type dopant;

An active layer formed on the n-type nitride semiconductor layer;

A p-type nitride semiconductor layer formed on the active layer and doped with a p-type dopant and including In; And

It provides a nitride semiconductor light emitting device comprising an electrode formed on each of the n-type nitride semiconductor layer and the p-type nitride semiconductor layer.

The amount of In contained in the p-type nitride semiconductor layer is preferably equal to or less than the p-type dopant doping amount, and the p-type dopant is preferably Mg. In particular, the nitride semiconductor material may be AlGaN.

Hereinafter, with reference to FIG. 1, the structure of this invention is demonstrated in detail.

As shown in FIG. 1, the nitride semiconductor light emitting device 10 according to the present invention includes a substrate 11; An n-type nitride semiconductor layer 12 formed on the substrate 10 and doped with an n-type dopant; An active layer 13 formed on the n-type nitride semiconductor layer; A p-type nitride semiconductor layer 14 formed on the active layer 13 and doped with a p-type dopant and including In; And electrodes 15, 16a, and 17a formed on the n-type nitride semiconductor layer 12 and the p-type nitride semiconductor layer 14, respectively.

The detailed description of each component is as follows.

Since the substrate 11 has the same crystal structure and crystal structure of the nitride semiconductor material grown thereon, and there is no commercial substrate forming a lattice match, a sapphire substrate is mainly used in consideration of lattice match. The sapphire substrate is a Hexa-Rhombo R3c symmetric crystal with a lattice constant of 13.001Å in the c-axis direction and 4.765Å in the a-axis direction, and has a lattice distance in the sapphire orientation Is characterized by having a C (0001) plane, an A (11 2 0) plane, an R (1 1 02) plane, and the like. In the case of the C surface of the sapphire substrate, the nitride semiconductor material is relatively easy to grow and is stable at high temperature, and thus, the sapphire substrate is mainly used as a substrate for a blue or green light emitting device.

The n-type nitride semiconductor layer 12 formed on the upper surface of the substrate 11 has an Al _x In _y Ga _(1-xy) N composition formula (where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y N dope semiconductor material), and representative nitride semiconductor materials include GaN, AlGaN, GaInN. As the dopant used for the doping of the n-type nitride semiconductor layer 12, Si, Ge, Se, Te, or C may be used, and double Si is typically used. The n-type nitride semiconductor layer 12 may be formed of a metal organic chemical vapor deposition (MOCVD) method, a molecular beam growth method (MBE), or a hybrid vapor deposition method (Hybride Vapor Phase Epitaxy). It is formed by growing on the substrate 11 using a known deposition process such as HVPE).

In general, a buffer layer 12 may be formed between the substrate 11 and the n-type nitride semiconductor layer 13 to mitigate lattice mismatch. As the buffer layer 12, a low temperature nucleus growth layer such as GaN or AlN having a thickness of several tens nm is usually used.

The active layer 13 is a layer for emitting light, and is usually formed by growing an InGaN layer as a well and growing an (Al) GaN layer as a barrier layer to form a multi-quantum well structure (MQW). In the blue light emitting diode, a multi-quantum well structure such as InGaN / GaN is used, and in the ultraviolet light emitting diode, a multi-quantum well structure such as GaN / AlGaN, InAlGaN / InAlGaN and InGaN / AlGaN is used. In order to improve the efficiency of the active layer, the internal quantum efficiency of the light emitting diode is improved by controlling the wavelength of light by changing the composition ratio of In or Al, or by changing the depth of the quantum wells, the number of active layers, and the thickness of the active layer. . The active layer 13 is formed on the n-type nitride semiconductor layer 12 using a known deposition process such as organometallic vapor deposition, molecular beam growth, or hybrid vapor deposition, like the n-type nitride semiconductor layer 12. Can be formed.

The p-type nitride semiconductor layer 14 is similar to the n-type nitride semiconductor layer 12, Al _x In _y Ga _(1-xy) N composition formula (where 0≤x≤1, 0≤y≤1, 0 ≦ x + y ≦ 1), and typical nitride semiconductor materials include GaN, AlGaN, and GaInN. As the dopant used for the doping of the p-type nitride semiconductor layer 14, Mg, Zn or Be, and the like, of which Mg is typically used. The p-type nitride semiconductor layer 14 is formed by growing the semiconductor material on the active layer 13 using a known deposition process such as organometallic vapor deposition, molecular beam growth, or hybrid vapor deposition.

A feature of the present invention is that when the p-type nitride semiconductor layer 14 is grown, In is added together with the dopant. In general, when the p-type nitride semiconductor layer 14 is grown, Mg, which is used as a p-type dopant, is difficult to be doped with a high doping concentration because the pulling rate is significantly lower than that of Ga. In addition, the doped Mg has a high activation energy and a large amount of energy bandwidth of the p-type nitride semiconductor layer is not activated. That is, the doped Mg has a low carrier concentration, and a large amount of unactivated Mg is present. In particular, in the case where the nitride used as the material of the p-type nitride semiconductor layer 14 is AlGaN having a high Al composition ratio, the higher the Al composition ratio, the more doped the Mg, the dopant, the lower the activity.

As described above, since the carrier concentration of Mg is low, the operating voltage of the light emitting device is increased, and the unactivated Mg combines with hydrogen to form defects in the p-type nitride semiconductor layer, which lowers reverse voltage characteristics and increases leakage current. , such as a decrease in transmittance of the p-type nitride semiconductor layer and a decrease in current diffusion.

In the present invention, when the p-type nitride semiconductor layer 14 is grown, by adding In together with the dopant Mg, the activation energy of the doped Mg can be reduced to obtain a higher carrier concentration by utilizing the role of the surfactant of In. Will be. By increasing the carrier concentration of the doped Mg through the addition of In, it is possible to lower the operating voltage. In addition, as the carrier concentration of Mg increases, unactivated Mg decreases, thereby reducing defects in the p-type nitride semiconductor layer, thereby improving reverse voltage characteristics, reducing leakage current, and increasing transmittance of the p-type nitride semiconductor layer. Can improve the current spreading. In particular, in AlGaN having a higher concentration of Al composition with lower Mg activity, the Mg activity can be increased more effectively.

In included in the p-type nitride semiconductor layer 14 may be implanted in the form of TMIn when the p-type nitride semiconductor layer 14 is grown by MOCVD. A p-type nitride semiconductor layer can be formed. However, due to the excessive injection of In, In may aggregate together in the p-type nitride semiconductor layer so that defects may occur. Therefore, the amount of In contained in the p-type nitride semiconductor layer is preferably less than the Mg concentration doped in the p-type nitride semiconductor layer. .

In general, nitride semiconductor layers containing In as a composition, such as InGaN, are grown at low temperatures of about 750 to 800 ° C. and nitride semiconductor layers containing In as a composition are not formed at high temperatures of 1000 ° C. or higher, so that In is nitride. It is preferable to grow the p-type nitride semiconductor layer 14 at a high temperature of about 1000 ° C. or more so that the composition of the semiconductor layer is simply added without changing the composition of the semiconductor layer.

The electrodes 15, 16a, and 16b are formed on the upper surface of the transparent electrode layer 15 and the n-type nitride semiconductor layer 12 formed in almost all regions of the upper surface of the p-type nitride semiconductor layer 14. The bonding electrode 16a and the p-side bonding electrode 16b formed on the upper surface of the transparent electrode layer 15 are included.

The transparent electrode layer 15 is suitable for lowering the contact resistance with the p-type nitride semiconductor layer 14 having a relatively high energy band gap and at the same time has good light transmittance for light emitted from the active layer 13 to be emitted upwards. It is required to be formed of a material. In general, the transparent electrode layer 15 mainly uses a double layer structure of Ni / Au, and has a relatively high contact resistance, but indium tin oxide (ITO), cadmium tin oxide (CTO), or titanium tungsten nitride (TiWN) to ensure good light transmittance. ) Can be used as a material. The transparent electrode layer 15 may be formed by a known deposition method such as chemical vapor deposition (CVD) and e-beam evaporator, or a process such as sputtering, and ohmic contact. It may be heat-treated at a temperature of about 400 to 900 ℃ to improve the properties of.

The n-side bonding electrode 16a may be formed on the n-type nitride semiconductor layer 12 as a single layer or a plurality of layers made of a material selected from the group consisting of Ti, Cr, Al, Cu, and Au. The n-side bonding electrode 16a may be formed on the n-type nitride semiconductor layer 12 by a known deposition method such as chemical vapor deposition and electron beam evaporation, or a process such as sputtering.

The p-side bonding electrode 16b is formed on the transparent electrode layer 15. The p-side bonding electrode 26b is the outermost electrode layer to be mounted on the lead through wire bonding. In general, the p-side bonding electrode 26b is made of Au or an alloy containing Au, and known deposition methods or sputtering methods such as chemical vapor deposition and electron beam evaporation are performed. It can be formed by a process such as.

In order to analyze the properties of the In-doped p-type nitride semiconductor layer, the inventors of the present invention grow a p-type GaN layer on a sapphire substrate by adding In through Metal Organic Chemical Vapor Deposition (MOCVD). A semiconductor light emitting device was fabricated, and various experiments were conducted on the grown p-type GaN layer and the fabricated nitride semiconductor light emitting device. Mg was used as the dopant for the p-type GaN layer. The results for this experiment are described below.

◎ XRD (X-Ray Diffraction) Analysis

2 shows the results of XRD (X-Ray Diffraction) analysis of the In addition p-type GaN layer.

2A is a graph showing the change in half width (FWHM) of the p-type GaN layer according to the amount of In added. As shown in FIG. 2A, when the p-type GaN layer was grown by adding different amounts of TMIn, XRD analysis showed that the half-width of the p-type GaN layer gradually decreased as the amount of TMIn was increased. These results indicate that the crystallinity of the p-type GaN layer is improved as the amount of In added to the p-type nitride semiconductor layer (GaN layer) increases. This is to improve the crystallinity of the p-type GaN layer by increasing the activity of the Mg added In as a dopant to reduce the amount of Mg acting as a defect of the p-type GaN layer.

2B is a graph showing a change in the interval between the peak of the p-type GaN layer and the peak of the sapphire substrate according to the amount of In added. Each material has a unique position at which the peak values appearing in the XRD analysis are formed. In general, the peak of the GaN layer is between the peak of the sapphire substrate and the peak of the InGaN layer. Therefore, assuming that the addition amount of In increases the generation of InGaN, the peak of GaN and the peak spacing of the sapphire substrate should gradually increase as the peak of GaN moves closer to the peak of InGaN. However, as shown in FIG. 2B, as the amount of In added increases, the peak spacing of the peak of GaN and the peak of the sapphire substrate decrease gradually. These results indicate that the InGaN layer is not formed even if the amount of In added is increased. InGaN layers are usually grown at relatively low temperatures (about 750 to 800 ° C), so when the GaN layers are grown at high temperatures (about 1000 ° C or more) as in the present invention, an InGaN layer is not formed, but only a GaN layer containing In. This is to be formed.

◎ Raman analysis

3 shows the Raman analysis result of the In addition p-type GaN layer. The Raman analysis result shown in FIG. 3 shows the formation of InGaN according to the crystallinity improvement of the p-type GaN layer and the addition of In, as shown in the XRD analysis result shown in FIG. 2.

First, as shown in the curve 31 of FIG. 3, a different amount of TMIn is added to grow a p-type GaN layer, and then Raman analysis is performed. appear. Yieoteuna about 4.51cm ^-1 value half-width of the p-type GaN layer without addition of In, the case of adding a p-type GaN layer grown upon a TMIn 30μmol / min, the half-width value was about 4.28cm ^-1. These results indicate that the crystallinity of the p-type GaN layer is improved as the amount of In added to the p-type GaN layer increases, as in the XRD analysis of the p-type GaN layer shown in FIG. 2A. This is to improve the crystallinity of the p-type GaN layer by reducing the amount of Mg that the added In increases the activity of the Mg used as a dopant to act as a defect of the p-type nitride semiconductor layer (GaN layer).

Subsequently, as shown in the curve 32 of FIG. 3, the amount of TMIn is added to grow the p-type GaN layer, and then Raman analysis is performed. As the amount of TMIn increases, the position where the peak appears gradually increases. It was. This means that the position of the peak of GaN gradually approaches the position of the peak of the sapphire substrate, as in the result of the peak spacing change of the XRD analysis shown in FIG. 2B. In other words, the peak position of GaN is far from the peak position of InGaN, and it can be seen that the InGaN layer is not formed even if the amount of In is increased. As described in the above-described XRD analysis results, the InGaN layer is usually grown at a relatively low temperature (about 750 to 800 ° C), so that the InGaN layer is formed when the GaN layer is grown at a high temperature (about 1000 ° C or more) as in the present invention. Instead, only a GaN layer containing In is formed. In addition, as a result of analyzing the stress according to the position of the peak, when In was not added, it showed 0.99GPa, but when TMIn was added at 30μmol / min during p-type GaN layer growth, the stress increased to 1.22GPa. The stress decreases due to the occurrence of stress defects during growth of the nitride semiconductor layer. The increase in stress is due to the decrease in defects during crystal growth, and the p-type GaN grown by adding In improves crystallinity. It can be seen that.

◎ Carrier Concentration Analysis

4 shows the carrier concentration analysis results of the In addition p-type GaN layer. This experiment was carried out after fabricating the device by varying the amount of TMIn added when growing the p-type GaN layer and performing a heat treatment for 30 seconds at 930 ℃. As the amount of TMIn added as shown in FIG. 4 increases, the carrier concentration increases. When TMIn was not added, even if the heat treatment was performed, the carrier concentration of the p-type GaN layer was only about 5 × 10 ¹⁷ . It was improved to about 9.0 × 10 ¹⁷ .

Mg doped in the p-type GaN layer has a high activation energy, which lowers the activity. Mg, which is not activated, combines with hydrogen and acts as a defect, thus adversely affecting device characteristics. As can be seen from this experiment, when In is added to grow a p-type GaN layer, the Mg activity increases, so that the amount of Mg acting as a carrier increases, thereby lowering the operating voltage of the light emitting device. In addition, since the carrier concentration increases with respect to the same doping amount, the amount of Mg acting as a defect is relatively reduced, thereby reducing defects in the p-type GaN layer and improving crystallinity. The improved crystallinity improves the reverse voltage and leakage current characteristics of the light emitting device, and increases the transmittance of the p-type GaN layer, thereby improving the luminous efficiency and luminance of the device.

◎ Current-Voltage Characteristic Analysis

5 is a graph comparing current-voltage characteristics of a nitride semiconductor light emitting device without adding In and a nitride semiconductor light emitting device having a p-type GaN layer containing In according to the present invention.

FIG. 5A is a graph comparing forward current-voltage characteristics. When a current of 20 mA flows as shown in FIG. 5A, an operating voltage of a conventional nitride semiconductor light emitting device, in which In is not added, is 3.78V, whereas In is added thereto. The operating voltage of the nitride semiconductor light emitting device was 3.63V, which lowered the operating voltage. This is because, as described above, when the p-type GaN layer is grown, the amount of Mg acting as a carrier is increased by increasing the activity of Mg by adding In.

FIG. 5B is a graph comparing reverse current-voltage characteristics. When a current of −10 μA flows as shown in FIG. 5B, the voltage of a conventional nitride semiconductor light emitting device without In is 13.3 V while In is added. The voltage of the nitride semiconductor light emitting device of the invention was -15.1V. This indicates that the breakdown current decreased while the breakdown voltage of the device increased. As described above, since the carrier concentration of the doped Mg is increased due to the addition of In, the amount of Mg acting as a defect is reduced, thereby reducing defects and improving crystallinity of the p-type GaN layer. to be.

◎ Analysis of transmittance of p-type GaN layer

Fig. 6 is a graph comparing the transmittance of the p-type GaN layer without adding In and the In-type p-type GaN layer of the present invention. As shown in FIG. 6, the transmittance 61 of the p-type GaN layer containing In is improved in the total light emitting region of 400 to 550 nm as compared with the transmittance 62 of the conventional GaN layer. As described above, the addition of In improves the carrier concentration of the Mg doped in the p-type GaN layer, thereby reducing the number of unactivated Mg that acts as a relatively small defect, and by the defects generated by the unactivated Mg. The transmittance of the p-type GaN layer is increased by reducing the generated light absorption.

◎ Analysis of light output of light emitting device

7 is a graph comparing light output characteristics of a nitride semiconductor light emitting device without adding In and a nitride semiconductor light emitting device having a p-type GaN layer containing In according to the present invention. As shown in FIG. 7, it can be seen that the light output 71 of the nitride semiconductor light emitting device to which In is added according to the present invention is improved compared to the light output 72 of the conventional nitride semiconductor light emitting device. As can be seen in FIG. 6, the p-type GaN layer has a higher transmittance by decreasing defects in the p-type GaN layer due to the dopant Mg deactivated due to the addition of In, and also the p-type GaN layer due to the deactivated dopant Mg. This is because the defect is reduced, thereby improving the diffusion of the current in the p-type GaN layer, so that light can be generated in the active layer having a larger area, thereby improving the luminous efficiency. That is, by adding In, defects in the p-type GaN layer are reduced, thereby improving transmittance of the p-type GaN layer and current diffusion in the p-type GaN layer, thereby increasing the light output of the light emitting device.

As shown in the experimental analysis results described above, by adding In when growing the p-type GaN layer, the carrier concentration of Mg used as the dopant of the p-type GaN layer can be increased. Since the amount of Mg used as a carrier increases, the operating voltage of the light emitting device can be lowered.

In addition, since the amount of activated Mg is increased, the amount of inactivated Mg acting as a defect of the p-type GaN layer is decreased, thereby improving the crystallinity of the p-type GaN layer. Due to defect reduction and crystallinity improvement of the p-type GaN layer, the transmittance is improved, characteristics of reverse voltage and leakage current are improved, and current diffusion in the p-type GaN layer is improved. Due to the improvement of the transmittance and leakage current characteristics of the p-type GaN layer, the luminous efficiency of the light emitting device and the brightness of emitted light are improved.

The present invention is not limited by the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims, and various forms of substitution, modification, and within the scope not departing from the technical spirit of the present invention described in the claims. It will be apparent to those skilled in the art that changes are possible.

As described above, according to the present invention, the carrier concentration of Mg used as the dopant of the p-type nitride semiconductor layer can be increased by adding In when the p-type nitride semiconductor layer is grown. Therefore, the amount of Mg used as a carrier increases, thereby reducing the operating voltage of the light emitting device.

Further, according to the present invention, the amount of inactivated Mg acting as a defect of the p-type nitride semiconductor layer is reduced, thereby improving the crystallinity of the p-type nitride semiconductor layer, thereby improving the transmittance of the p-type nitride semiconductor layer and The leakage current characteristics are improved and current diffusion in the p-type nitride semiconductor layer is improved. As a result, the luminous efficiency of the light emitting device and the brightness of the emitted light are improved.

Claims (4)

Board; An n-type nitride semiconductor layer formed on the substrate and doped with an n-type dopant; An active layer formed on the n-type nitride semiconductor layer; A p-type nitride semiconductor layer formed on the active layer and including In, which is doped with a p-type dopant and added in an amount less than or equal to the doping amount of the p-type dopant; And And an electrode formed on the n-type nitride semiconductor layer and the p-type nitride semiconductor layer, respectively. delete The method of claim 1, The p-type dopant is a nitride semiconductor light emitting device, characterized in that Mg. The method of claim 1, The nitride semiconductor material is AlGaN, characterized in that the nitride semiconductor light emitting device.

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