KR101199796B1 - Nitride semiconductor light emitting device and method for manufacturing thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nitride semiconductor light emitting device and a method for manufacturing the same, to provide good lattice matching within a layer of a nitride material constituting a nitride semiconductor light emitting device and good lattice matching between layers of a nitride material. According to the present invention, a buffer layer, an n-type semiconductor layer, an active layer and a p-type semiconductor layer are sequentially stacked on a base substrate. In this case, at least one of the buffer layer, the n-type semiconductor layer, the active layer, and the p-type semiconductor layer supplies Group III and Group V sources, and supplies at least one of the Group III or Group V sources in a stepped or curved manner. Form the layer. Therefore, since the composition inside the layer can be changed while the layer is integrally formed, good lattice match with the layer and other neighboring layers can be ensured, including good lattice match in the layer. This can reduce the occurrence of cracks, distortions, and dislocations due to the lattice constants and thermal expansion coefficient differences between the layer and other layers formed above and below the layer, and improves the internal quantum efficiency to improve nitride quantum semiconductors. The luminous efficiency of the light emitting device can be improved.

Description

Nitride-based semiconductor light emitting device and method for manufacturing the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor light emitting device and a method for manufacturing the same, and more particularly, to a nitride based semiconductor light emitting device and a method for manufacturing the same, which provide good lattice matching between layers of nitride materials constituting a nitride semiconductor light emitting device.

In general, nitride semiconductor materials such as gallium nitride (GaN) and aluminum nitride (AlN), which include a group V source such as nitrogen (N) and a group III source such as gallium (Ga) or aluminum (Al), have a high thermal stability. Since it has an excellent and direct transition energy band structure, it has recently been widely used as a material for nitride-based semiconductor light emitting devices in the blue and ultraviolet regions. In particular, blue and green light emitting devices using gallium nitride (GaN) have been used in various applications such as large-scale color flat panel displays, traffic lights, indoor lighting, high-density light sources, high resolution output systems and optical communication.

The nitride semiconductor light emitting device has a structure of a buffer layer, an n-type semiconductor layer, an active layer, a p-type semiconductor layer, and an electrode on a base substrate.

At this time, the buffer layer is formed in order to suppress the occurrence of cracks, warpages or dislocations in the n-type semiconductor layer due to the difference in lattice constant and thermal expansion coefficient between the base substrate and the n-type semiconductor layer. The buffer layer is formed in multiple layers so as to be gradually changed.

The active layer is a region where electrons and holes are recombined, and has a structure in which a quantum well layer is disposed between quantum barrier layers. The wavelength of light emitted from the nitride semiconductor light emitting device is determined according to the type of the material forming the active layer.

The active layer includes a single quantum well (SQW) structure having one quantum well layer, a multi quantum well (MQW) structure having a plurality of quantum well layers, a superlattice (SL) structure, and the like. have. Among these, in particular, the active layer of the multi-quantum well structure is actively used because it has better luminous efficiency compared to the current and has a high luminous output compared to the single quantum well structure.

The luminous efficiency of the nitride-based semiconductor device is determined by the probability of recombination of electrons and holes that are primarily involved in light emission in the active layer, that is, internal quantum efficiency (IQE). The internal quantum efficiency refers to the number of photons compared to the number of recombined electrons.In order to improve the internal quantum efficiency, electrons and holes flow into the active layer when a voltage is applied, and they effectively trap electrons and holes in the active layer. In other words, the characteristics of recombination of electrons and holes in the active layer should be considered as a whole.

In order to improve the internal quantum efficiency, research has been conducted mainly toward improving the structure of the active layer itself or increasing the number of electrons and holes participating in the emission process. For example, in order to improve the internal quantum efficiency of a nitride semiconductor light emitting device, a method of providing a symmetrical superlattice structure as a cladding layer between an active layer and an n-type semiconductor layer or between an active layer and a p-type semiconductor layer has been proposed.

In addition, an n-type semiconductor layer and a p-type semiconductor layer have been introduced to form a multilayer in order to improve the performance of the nitride semiconductor light emitting device.

Since the components constituting the nitride semiconductor light emitting device according to the prior art, for example, the buffer layer, the n-type semiconductor layer, the active layer and the p-type semiconductor layer are each formed in multiple layers, the manufacturing process of the nitride semiconductor light emitting device is complicated. It may take a long process time to manufacture a nitride-based semiconductor light emitting device.

In addition, since each component is formed in multiple layers, there is a possibility that a problem occurs at the interface between the layers constituting the component, and there is a need to consider the interface compatibility between the layers constituting the component.

Accordingly, an object of the present invention is to provide a nitride-based semiconductor light emitting device and a method of manufacturing the same that can improve the lattice matching between the layers constituting the nitride-based semiconductor light emitting device.

Another object of the present invention is to provide a nitride-based semiconductor light emitting device having a single structure and a method for manufacturing the same, which can solve the interlayer interfacial compatibility problem of the multi-layer component.

In order to achieve the above object, the present invention comprises the steps of preparing a base substrate, a buffer layer forming step of forming a buffer layer on the base substrate, an n-type semiconductor layer forming step of forming an n-type semiconductor layer on the buffer layer, and Provided are an active layer forming step of forming an active layer on an n-type semiconductor layer, and a p-type semiconductor layer forming step of forming a p-type semiconductor layer on the active layer. In particular, in at least one of the buffer layer forming step, the n-type semiconductor layer forming step, the active layer forming step, and the p-type semiconductor layer forming step, the Group III and Group V sources are supplied, The at least one supply amount is varied in steps or curves to form the layer.

In the method of manufacturing a nitride-based semiconductor light emitting device according to the present invention, when supplying the Group III and Group V source, one of the Group III or Group V source is constantly supplied, the other source is a stepped or curved It can be supplied in a variable form.

In the method of manufacturing a nitride-based semiconductor light emitting device according to the present invention, the Group III source may contain at least one of B, Al, Ga, In, the Group V source may contain N.

In the method of manufacturing a nitride-based semiconductor light emitting device according to the invention, the buffer layer, the n-type semiconductor layer, the active layer and the p-type semiconductor layer comprises one of GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN. do.

In the method of manufacturing a nitride-based semiconductor light emitting device according to the present invention, the buffer layer forming step, by supplying a Group III and Group V source, by varying the supply of one of the Group III or Group V source to step or curve shape Forming a nitride nucleus growth layer of a III-V material on the base substrate, and subsequently supplying the III- and V-group sources after the nitride nucleus growth layer is formed; The method may include forming a buffer layer of a III-V material to cover the base substrate based on the nitride nucleus growth layer by varying a supply amount of one of the sources into a stepped shape or a curved shape.

The present invention also provides a method of preparing a base substrate, a buffer layer forming step of forming a buffer layer on the base substrate, an n-type semiconductor layer forming step of forming an n-type semiconductor layer on the buffer layer, and the n-type semiconductor layer. an n-type cladding layer forming step of forming an n-type cladding layer, an active layer forming step of forming an active layer on the n-type cladding layer, a p-type cladding layer forming step of forming a p-type cladding layer on the active layer, and the p Provided is a method for manufacturing a nitride-based semiconductor light emitting device comprising the step of forming a p-type semiconductor layer to form a p-type semiconductor layer on the type clad layer. In particular, in at least one of the buffer layer forming step, the n-type semiconductor layer forming step, the n-type cladding layer forming step, the active layer forming step, the p-type cladding layer forming step and the p-type semiconductor layer forming step, III The group and group V sources are supplied, but at least one of the group III or group V sources is varied in a stepped or curved form to form a corresponding layer.

The present invention also provides a nitride-based semiconductor light emitting device comprising a base substrate, a buffer layer, an n-type semiconductor layer, an active layer and a p-type semiconductor layer. The buffer layer is formed on the base substrate. The n-type semiconductor layer is formed on the buffer layer. The active layer is formed on the n-type semiconductor layer. The p-type semiconductor layer is formed on the active layer. In particular, at least one of the buffer layer, the n-type semiconductor layer, the active layer, and the p-type semiconductor layer supplies a Group III and Group V source, and at least one supply amount of the Group III or Group V source is stepped or curved. Variable to form a corresponding layer.

The nitride semiconductor light emitting device according to the present invention further includes a nitride nucleus growth layer formed between the base substrate and the buffer layer. In this case, the nitride nucleus growth layer and the buffer layer may supply the Group III and Group V sources, and may be continuously formed by varying the supply amount of the Group III or Group V source in a stepped or curved shape.

The present invention also provides a nitride-based semiconductor light emitting device comprising a base substrate, a buffer layer, an n-type semiconductor layer, an n-type cladding layer, an active layer, a p-type cladding layer and a p-type semiconductor layer. The buffer layer is formed on the base substrate. The n-type semiconductor layer is formed on the buffer layer. The n-type cladding layer is formed on the n-type semiconductor layer. The active layer is formed on the n-type clad layer. The p-type cladding layer is formed on the active layer. The p-type semiconductor layer is formed on the p-type cladding layer. In particular, at least one of the buffer layer, the n-type semiconductor layer, the n-type cladding layer, the active layer, the p-type cladding layer, and the p-type semiconductor layer supplies a Group III and Group V source, but is a Group III or Group V At least one supply amount in the source is varied in a stepped or curved shape to form a corresponding layer.

According to the structure of the present invention, when forming a buffer layer, an n-type semiconductor layer, an n-type cladding layer, an active layer, a p-type cladding layer or a p-type semiconductor layer of the nitride material on the base substrate, the supply amount of the Group V source or Group III source It is possible to change the composition inside the layer while forming the layer integrally by forming the layer by varying the shape into a stepped shape or a curve shape, so that another layer neighboring the layer including good lattice match in the layer can be changed. Good lattice matchability with can be ensured. As a result, it is possible to reduce the occurrence of cracks, distortions, and dislocations due to differences in lattice constants and coefficients of thermal expansion between the layer and other layers formed above and below the layer.

In addition, by ensuring good lattice matching between the layer and other neighboring layers, including good lattice matching in the layer, the crystal defects are reduced, thereby ultimately improving the internal quantum efficiency to improve the luminous efficiency of the nitride semiconductor light emitting device. Can be improved.

1 is a cross-sectional view showing a nitride-based semiconductor light emitting device according to an embodiment of the present invention.
2 is a flowchart illustrating a method of manufacturing the nitride-based semiconductor light emitting device of FIG. 1.
3 to 7 are cross-sectional views showing each step according to the manufacturing method of FIG.
8 is a waveform diagram illustrating an example of supply conditions of a group III source and a group V source for forming the active layer of FIG. 2.
9 is a waveform diagram illustrating another example of supply conditions of a group III source and a group V source for forming the active layer of FIG. 2.

In the following description, only parts necessary for understanding the embodiments of the present invention will be described, and the description of other parts will be omitted so as not to obscure the gist of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and the inventor is not limited to the meaning of the terms in order to describe his invention in the best way. It should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely preferred embodiments of the present invention, and are not intended to represent all of the technical ideas of the present invention, so that various equivalents And variations are possible.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view showing a nitride-based semiconductor light emitting device 10 according to an embodiment of the present invention.

Referring to FIG. 1, a nitride based semiconductor light emitting device 10 according to an exemplary embodiment of the present invention may include a base substrate 11, a buffer layer 13, an n-type semiconductor layer 14, an active layer 15, and a p-type semiconductor layer. And 16, further including a nitride nucleus growth layer 12, an n-type cladding layer 14a, and a p-type cladding layer 16a.

The nitride semiconductor light emitting device 10 according to the present embodiment includes a base substrate 11, a nitride nucleus growth layer 12, a buffer layer 13, and an n-type semiconductor layer 14 sequentially formed on the base substrate 11. ), n-type cladding layer 14a, active layer 15, p-type cladding layer 16a, and p-type semiconductor layer 16. In the nitride-based semiconductor light emitting device 10, a p-type electrode and an n-type electrode are formed to be connected to the outside. For example, in the nitride-based semiconductor light emitting device 10, a portion of the p-type semiconductor layer 16, the p-type cladding layer 16a, and the active layer 15 is removed by a mesa etching process, and the n-type semiconductor is removed. Some top surfaces of layer 14 may be exposed. An n-type electrode is formed on the exposed n-type semiconductor layer 14. A transparent electrode layer made of indium tin oxide (ITO) or the like is formed on the p-type semiconductor layer 16, and a p-type electrode may be formed thereon.

At this time, the nitride nucleus growth layer 12, the buffer layer 13, the n-type semiconductor layer 14, the n-type cladding layer 14a, the active layer 15, the p-type cladding layer and the p-type semiconductor layer 16 are group III. And a group V source. In this case, B, Al, Ga, In, or the like may be used as the group III source. N, P, As, etc. may be used as the group V source. Each layer may be made of a material such as GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN, and have different chemical compositions.

The base substrate 11 may be made of a material suitable for growing a nitride semiconductor single crystal. In this case, the base substrate 11 includes sapphire, silicon (Si), zinc oxide (ZnO), gallium nitride (GaN), gallium arsenide (GaAs), silicon carbide (SiC), and aluminum knight. It may be made of an element or a compound such as lide (AlN), magnesium oxide (MgO). For example, a sapphire substrate having a c surface ({0001} surface) may be used as the base substrate 11, and the nitride nucleus growth layer 12, the buffer layer 13, the n-type cladding layer 14a, and n are formed on the c surface. The semiconductor layer 14, the active layer 15, the p-type cladding layer 16a, and the p-type semiconductor layer 16 may be sequentially formed.

The nitride nucleus growth layer 12 is formed on the base substrate 11. In this case, the nitride nucleus growth layer 12 may be made of GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN, or the like.

The buffer layer 13 is to reduce the lattice constant difference between the base substrate 11 and the n-type semiconductor layer 14 and is formed on the base substrate 11 based on the nitride nucleus growth layer 12. In addition, the buffer layer 13 functions to alleviate stress between the base substrate 11 and the n-type semiconductor layer 14, such as to prevent melt-back etching due to the chemical action of the base substrate 11. Perform. For example, the buffer layer 13 may be made of GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN, or the like. The buffer layer 13 may include metal organic chemical vapor deposition (MOCVD), hydride vapor phase epitaxy (HVPE) or molecular beam growth (MBE), metal organic chemical vapor phase epitaxy (MOCVPE). ) And the like can be used.

The n-type semiconductor layer 14 is formed on the buffer layer 13. The n-type semiconductor layer 14 is formed of gallium nitride (GaN), and silicon may be doped to lower the driving voltage.

The n-type cladding layer 14a is formed on the n-type semiconductor layer 14. In this case, the n-type cladding layer 14a may be formed in a superlattice structure, and the superlattice structure may be formed symmetrically or asymmetrically.

The active layer 15 is formed on the n-type cladding layer 14a. The active layer 15 may be formed in a quantum well structure using a method such as MOCVD, HVPE, MBE, MOCVPE, and the like. In the active layer 15, light is generated by combining holes flowing through the p-type semiconductor layer 16 and electrons flowing through the n-type semiconductor layer 14, where a quantum well corresponds to an excitation level or an energy band gap difference. Light of energy is emitted.

The p-type cladding layer 16a is formed on the active layer 15. In this case, the p-type cladding layer 16a may be formed in a superlattice structure, and the superlattice structure may be formed symmetrically or asymmetrically.

At this time, the n-type and p-type cladding layers 14a and 16a are formed in a superlattice structure having a symmetrical or asymmetrical energy bandgap, thereby inducing electrons and holes into the active layer 15 participating in the light emission process. By adjusting the internal quantum efficiency can be improved. That is, through the n-type and p-type cladding layers 14a and 16a, the efficiency of inflow of holes and the efficiency of binding into the active layer 15 of the introduced electrons and holes may be improved, thereby ultimately improving the internal quantum efficiency.

The p-type semiconductor layer 16 is formed on the p-type cladding layer 16a. The p-type semiconductor layer 16 is a semiconductor layer made of a nitride material doped with p-type conductive impurities such as Mg, Zn, Be, and the like. The p-type semiconductor layer 16 has a p-type AlGaN layer adjacent to the light emitting region and serves as an electron blocking layer (EBL), and p-type GaN and (Al) Ga (In) adjacent to the p-type AlGaN layer. It may consist of N layers.

In particular, in the present embodiment, among the buffer layer 13, the n-type semiconductor layer 14, the n-type cladding layer 14a, the active layer 15, the p-type cladding layer, and the p-type semiconductor layer 16, which were formed as a conventional multilayer, When at least one is formed by supplying a group III and group V source, at least one of the group III or group V sources is varied in a stepped form (FIG. 8) or a curved form (FIG. 9) to form a corresponding layer. do.

As described above, in the nitride-based semiconductor light emitting device 10 according to the present exemplary embodiment, the nitride layer buffer layer 13, the n-type semiconductor layer 14, the n-type cladding layer 14a, and the active layer 15 are formed on the base substrate 11. When the p-type cladding layer 16a or the p-type semiconductor layer 16 is formed, the supply amount of the group III source or the group V source is varied stepwise or curved to form the layer, thereby integrally forming the layer. While forming, the composition inside the layer can be changed. This ensures good lattice match between the layer and other neighboring layers, including good lattice match within the layer. In addition, it is possible to reduce the occurrence of cracks, distortions, and dislocations due to the difference in lattice constants and thermal expansion coefficients between the layer and other layers formed above and below the layer.

In addition, by ensuring good lattice match between the layer and other neighboring layers, including good lattice match in the layer, and reducing crystal defects, the internal quantum efficiency is ultimately improved, thereby improving the nitride-based semiconductor light emitting device 10. The luminous efficiency can be improved.

The nitride-based semiconductor light emitting device 10 according to the present exemplary embodiment has been described in which an active layer 15 is formed by supplying Group III and Group V sources and varying at least one of the Group III and Group V sources. For example, the active layer 15 may be formed by varying the supply amount of the group V source while the group III source is constantly supplied. At this time, the group V source, as shown in Figure 8, can be continuously supplied by varying the supply amount in the step type. That is, assuming that the active layer 15 is formed at t3 time, the supply amount of the Group V source in the 0 to t1, t1 to t2 and t2 to t3 sections, respectively, while the supply amount of the Group III source is kept constant for the t3 time. Is changed to step type to form the active layer 15. At this time, since there is a difference in the supply amount of the Group V source in the sections 0 to t1, t1 to t2 and t2 to t3, respectively, the portions 15a, 15b and 15c respectively formed in the sections 0 to t1, t1 to t2 and t2 to t3. The internal composition of the is changed. However, since the group V source is continuously supplied in a stepped form, the active layer 15 to be formed is integrally formed with a change in the internal composition. Therefore, good lattice matching in the active layer 15 can be ensured. In addition, the supply amount of the Group III and Group V sources is varied in a step shape in consideration of lattice match between the neighboring layers such as the n-type cladding layer 14a and the p-type cladding layer 16a, whereby the active layer 15 and the n-type Good lattice matching between the cladding layer 14a, the active layer 15 and the p-type cladding layer 16a can be ensured.

Alternatively, the group V source may be continuously supplied by varying the supply amount in a curved shape, as shown in FIG. 9. In addition, the group V source may be continuously supplied by varying the supply amount in a mixed form of step type and curve type. And the group III source can be supplied in a continuous amount.

On the other hand, the nitride nucleus growth layer 12 and the buffer layer 13 may be formed by sequentially stacking by going through separate processes. Alternatively, the nitride nucleus growth layer 12 and the buffer layer 13 may be continuously processed in one process to form the nitride nucleus growth layer 12 and the buffer layer 13 of the III-V material in a row in a row. . That is, as described above, the nitride nucleus growth layer 12 and the buffer layer 13 of the III-V material may be continuously formed in a batch by varying the supply amount of at least one of the group III or group V sources.

In the present embodiment, an example is described in which a layer of a nitride material constituting the nitride-based semiconductor light emitting device 10 is formed by varying the supply amount of the group V source while the group III source is constantly supplied. It is not. That is, in a state in which the Group V source is constantly supplied, the supply amount of the Group III source can be varied to form a nitride material layer. Alternatively, the nitride material layer may be formed while the group III source and the group V source are varied together.

The method of manufacturing the nitride-based semiconductor light emitting device 10 according to the present embodiment will be described with reference to FIGS. 2 to 9 as follows. 2 is a flowchart illustrating a method of manufacturing the nitride semiconductor light emitting device 10 of FIG. 1. 3 to 7 are cross-sectional views showing each step according to the manufacturing method of FIG. 8 is a waveform diagram illustrating an example of supply conditions of a group III source and a group V source for forming the active layer 15 of FIG. 2. 9 is a waveform diagram illustrating another example of supply conditions of a group III source and a group V source for forming the active layer 15 of FIG. 2. On the other hand, in the manufacturing method according to the present embodiment, the buffer layer 13, the n-type semiconductor layer 14, the n-type cladding layer 14a, the active layer 15, the p-type cladding layer 16a and the p-type semiconductor layer 16 ), An example is described in which the active layer 15 is formed by varying the supply amount of a group V source or a group III source into a stepped shape or a curved shape.

First, as shown in FIG. 3, the base substrate 11 is prepared in step S21. The base substrate 11 may include sapphire, silicon (Si), zinc oxide (ZnO), gallium nitride (GaN), gallium arsenide (GaAs), silicon carbide (SiC), aluminum nitride (AlN), magnesium oxide ( Substrates made of an element or compound material such as MgO) may be used. In this embodiment, a sapphire substrate having a c surface ({0001} surface) is used as the base substrate 11.

Next, as shown in FIG. 4, the nitride nucleus growth layer 12 is formed on the base substrate 11 in step S23. In this case, the nitride nucleus growth layer 12 may be formed using MOCVD, HVPE, MBE, or MOCVPE. For example, the nitride nucleus growth layer 12 formed using Group III and Group V sources may be made of GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN, or the like.

Next, as shown in FIG. 4, in step S25, the buffer layer 13 covering the nitride nucleus growth layer 12 is formed on the base substrate 11. The buffer layer 13 is used to reduce the lattice constant difference between the base substrate 11 and the n-type semiconductor layer 14. The nitride nucleus growth layer 12 is formed on the base substrate 11 based on the nitride nucleus growth layer 12. ) Is formed to cover.

In this case, the forming of the nitride nucleus growth layer 12 (S23) and the forming of the buffer layer 13 may be performed in separate steps as described above, or the nitride nucleus growth may be continuously performed in one process. The layer 12 and the buffer layer 13 can be formed continuously and collectively. That is, the nitride nucleus growth layer 12 and the buffer layer 13 can be continuously formed in a batch by varying the supply amount of the group III or group V source.

Next, as shown in FIG. 5, the n-type semiconductor layer 14 is formed on the buffer layer 13 in step S27. In this case, the n-type semiconductor layer 14 is formed of aluminum gallium nitride (AlGaN) -based, silicon may be doped to lower the driving voltage.

Next, as shown in FIG. 5, an n-type cladding layer 14a is formed on the n-type semiconductor layer 14 in step S29. In this case, the n-type cladding layer 14a may be formed in a superlattice structure, and the superlattice structure may be formed symmetrically or asymmetrically.

Next, as shown in FIG. 6, the active layer 15 is formed on the n-type cladding layer 14a in step S31. In this case, the active layer 15 may be formed in a quantum well structure. In the active layer 15, holes flowing through the p-type semiconductor layer (16 in FIG. 7) to be formed next and electrons flowing through the n-type semiconductor layer 14 are combined to generate light.

In particular, the active layer 15 is formed by varying the supply amount of the group III source or the group V source into a step type (FIG. 8) or a curved type (FIG. 9). That is, referring to FIG. 8, the active layer 15 may be formed by varying the supply amount of the group V source while constantly supplying the group III source. At this time, the group V source may be continuously supplied by varying the supply amount in step type. That is, assuming that the active layer 15 is formed at t3 time, the supply amount of the Group V source in the 0 to t1, t1 to t2 and t2 to t3 sections, respectively, while the supply amount of the Group III source is kept constant for the t3 time. Is changed to form the active layer 15. At this time, since there is a difference in the supply amount of the Group V source in the sections 0 to t1, t1 to t2 and t2 to t3, respectively, the portions 15a, 15b and 15c respectively formed in the sections 0 to t1, t1 to t2 and t2 to t3. The internal composition of the is changed. However, since the group V source is continuously supplied in a stepped form, the active layer 15 to be formed is integrally formed with a change in the internal composition.

As a result, good lattice matching in the active layer 15 can be ensured. In addition, the supply amount of the Group III and Group V sources is varied in a step shape in consideration of lattice matching with other neighboring layers, the n-type cladding layer 14a and the p-type cladding layer (16a in FIG. 7), whereby the active layer 15 And good lattice matching between the n-type cladding layer 14a, the active layer 15 and the p-type cladding layer (16a in FIG. 7) can be ensured.

Alternatively, the group V source may be continuously supplied by varying the supply amount in a curved shape, as shown in FIG. 9.

Next, as shown in FIG. 7, the p-type cladding layer 16a is formed on the active layer 14 in step S33. In this case, the p-type cladding layer 16a may be formed in a superlattice structure, and the superlattice structure may be formed symmetrically or asymmetrically.

As shown in FIG. 7, the p-type semiconductor layer 16 is formed on the p-type cladding layer 16a in step S35. At this time, the p-type semiconductor layer 16 is a semiconductor layer of a nitride material doped with p-type conductive impurities such as Mg, Zn, Be and the like. The p-type semiconductor layer 16 may be formed of a p-type AlGaN layer adjacent to the light emitting region and serving as an electron barrier layer (EBL), and a p-type AlGaInN layer adjacent to the p-type AlGaN layer.

Thereafter, a process of forming an external connection terminal of the nitride semiconductor light emitting device 10 is performed. In other words, a portion of the p-type semiconductor layer 16, the p-type cladding layer 16a and the active layer 15 are removed by a mesa etching process to expose a part of the upper surface of the n-type semiconductor layer 14 To form a structure. An n-type electrode is formed on the exposed n-type semiconductor layer 14. On the p-type semiconductor layer 16, a transparent electrode layer made of indium tin oxide (ITO) or the like is formed, and a p-type electrode is formed thereon.

In this case, the transparent electrode layer is formed on the p-type semiconductor layer 16. The transparent electrode layer is a kind of electrode contact layer, so that current can be well transmitted to the p-type electrode. Such a transparent electrode layer may be made of, for example, ITO, ZnO, RuOx, TiOx, IrOx, or the like as a transparent oxide film. When the basic laminated structure from the base substrate 11 to the transparent electrode layer is completed as described above, a part of the n-type semiconductor layer 14 is exposed by performing wet etching, for example, anisotropic wet etching, from the surface. After the etching process is performed, titanium (Ti), silver (Au), and the like are deposited on the n-type semiconductor layer 14 to form an n-type electrode, and nickel (Ni) and the like are deposited on the transparent electrode layer to form a p-type electrode. Form.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of specific examples for the purpose of understanding and are not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is apparent to those skilled in the art that other modifications based on the technical idea of the present invention may be implemented.

10: nitride semiconductor light emitting device
11: base substrate
12: nitride nucleus growth layer
13: buffer layer
14: n-type semiconductor layer
14a: n-type cladding layer
15: active layer
16a: p-type cladding layer
16: p-type semiconductor layer

Claims (9)

Preparing a base substrate;
A buffer layer forming step of forming a buffer layer on the base substrate;
An n-type semiconductor layer forming step of forming an n-type semiconductor layer on the buffer layer;
An active layer forming step of forming an active layer on the n-type semiconductor layer;
A p-type semiconductor layer forming step of forming a p-type semiconductor layer on the active layer;
In the buffer layer forming step, the n-type semiconductor layer forming step, the active layer forming step and the p-type semiconductor layer forming step, the Group III and Group V sources are supplied, and the supply amount of the Group III and Group V sources is stepped or curved. Variable and fed together in a mold to form the respective layers in succession,
The Group III source contains at least one of B, Al, Ga, and In, the Group V source contains N,
The buffer layer, the n-type semiconductor layer, the active layer and the p-type semiconductor layer is one of GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN,
The buffer layer forming step,
Supplying Group III and Group V sources, and varying the amount of the Group III and Group V sources to be stepped or curved to form a nitride nucleus growth layer of Group III-V material on the base substrate;
After the nitride nucleus growth layer is formed, the group III and group V sources are continuously supplied, and the supply amount of the group III and group V sources is varied together in a stepped or curved form to form the nitride nucleus growth layer. Forming a buffer layer of a III-V material to cover the base substrate;
Method of manufacturing a nitride-based semiconductor light emitting device comprising a. delete delete delete delete Preparing a base substrate;
A buffer layer forming step of forming a buffer layer on the base substrate;
An n-type semiconductor layer forming step of forming an n-type semiconductor layer on the buffer layer;
An n-type cladding layer forming step of forming an n-type cladding layer on the n-type semiconductor layer;
An active layer forming step of forming an active layer on the n-type clad layer;
Forming a p-type cladding layer on the active layer;
A p-type semiconductor layer forming step of forming a p-type semiconductor layer on the p-type cladding layer;
In the buffer layer forming step, the n-type semiconductor layer forming step, the n-type cladding layer forming step, the active layer forming step, the p-type cladding layer forming step and the p-type semiconductor layer forming step, group III and group V source Supplying, but supplying the amounts of the Group III and Group V sources together in step or curve shape to form the respective layers in succession,
The buffer layer, the n-type semiconductor layer, the active layer and the p-type semiconductor layer is one of GaN, AlN, AlGaN, InGaN, AlInN, AlGaInN, AlGaInBN,
The buffer layer forming step,
Supplying Group III and Group V sources, and varying the amount of the Group III and Group V sources to be stepped or curved to form a nitride nucleus growth layer of Group III-V material on the base substrate;
After the nitride nucleus growth layer is formed, the Group III and Group V sources are continuously supplied, and the supply amount of the Group III and Group V sources is varied together in a stepped or curved form to form the nitride nucleus growth layer. Forming a buffer layer of a III-V material to cover the base substrate;
Method of manufacturing a nitride-based semiconductor light emitting device comprising a. delete delete delete

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