KR20140036405A - Light emitting diode and manufacturing method thereof - Google Patents

Abstract

A light emitting diode is disclosed. The light emitting diode comprises: a transparent substrate having a first surface and a second surface; a semiconductor laminated structure comprising a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer and disposed on the first surface of the transparent substrate; and a refractive index adjusting layer formed to have a pattern of a nanostructure on the second surface of the transparent substrate.

Description

LIGHT EMITTING DIODE AND MANUFACTURING METHOD THEREOF

The present invention relates to a light emitting diode and a method of manufacturing the same, and more particularly, to a light emitting diode having a refractive index control layer on the lower surface of the substrate and a method of manufacturing the same.

Gallium nitride-based light emitting diodes have high energy conversion efficiency, long life, high light directivity, low voltage driving, no preheating time, no complicated driving circuit, and strong shock and vibration. The system can be implemented and is expected to be a solid-state lighting source that will replace conventional light sources such as incandescent, fluorescent and mercury lamps in the near future.

In order to use a gallium nitride-based light emitting diode as a white light source to replace a mercury lamp or a fluorescent lamp, it must not only have excellent thermal stability but also be able to emit high power at low power consumption. Horizontal gallium nitride-based light emitting diodes, which are widely used as white light sources, have the advantages of relatively low manufacturing cost and simple manufacturing process. However, they have disadvantages of being inadequate to be used as high power sources with high applied current and large area. .

A gallium nitride-based light emitting diode having a horizontal structure includes a transparent sapphire substrate and a semiconductor stacked structure formed on the sapphire substrate. The semiconductor laminated structure includes a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer in a direction away from the sapphire substrate.

In the manufacture of the gallium nitride-based light emitting diode of the above-described horizontal structure, one of the parts that can greatly improve the light output of the light emitting diode device is a substrate. When the substrate, particularly the sapphire substrate, has only a smooth planar structure, the light is absorbed by the substrate and the light is long, so that the light is trapped inside the light emitting diode. On the other hand, a light emitting diode has been proposed to form an uneven pattern on the upper surface of the substrate, that is, the interface between the first conductive semiconductor layer and the substrate, to scatter light at the interface, thereby improving light extraction efficiency.

Furthermore, efforts have been made to improve the light extraction efficiency by artificially modifying the surface of the lower surface of the substrate. To this end, conventionally, there has been an attempt to increase light extraction efficiency by patterning the lower surface of the substrate by an etching method. However, there is a disadvantage that the etching of the substrate is difficult and takes a long time to perform the etching.

SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting diode and a method for manufacturing the same, which can improve light extraction efficiency through surface texturing on a lower surface of a substrate.

A light emitting diode according to embodiments of the present invention comprises: a translucent substrate comprising a first surface and a second surface; A semiconductor stacked structure comprising a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, the semiconductor stacked structure formed on a first surface of the substrate; It includes a refractive index control layer formed to have a pattern on the second surface of the substrate.

In one embodiment, the refractive index control layer may be formed by nano imprint, so that the pattern has a plurality of nanostructures.

In one embodiment, the refractive index control layer is formed by the deposition of a metal oxide having a rock salt (rock salt) structure, the pattern may include a plurality of pyramid structures.

In one embodiment, the refractive index control layer is M _x M ' _{1 -x} O (x≤1, M = Mg, Ca, Zn, Ni, at least one of M' = Be, Ca, Sr, Ba) It may include one or more metal oxide layers formed by depositing a metal oxide represented by.

In one embodiment, the metal oxide includes an impurity doped to the surface, the impurity is B, In, Zn, Tl, Al, Sn, Ga, Te, Si, C, Ge, N, P, As, It may be selected from the group consisting of Sb, Bi, S, Se, Br, I, Ti and a compound comprising one or more thereof.

In example embodiments, a pattern including a plurality of convex portions of a pattern may be formed on a first surface of the substrate, and a semiconductor laminate structure may be formed on the pattern.

In example embodiments, the substrate may include a sapphire substrate and the semiconductor stack structure may include a gallium nitride based semiconductor.

In example embodiments, the semiconductor stacked structure may include a portion of the second conductive semiconductor layer and the active layer to expose a portion of the first conductive semiconductor layer, and a transparent electrode layer on the second conductive semiconductor layer. The first electrode pad and the second electrode pad may be formed in the exposed region and the transparent electrode layer of the first conductive semiconductor layer.

According to another aspect of the present invention, there is provided a light emitting diode manufacturing method, comprising: preparing a light-transmissive substrate having a first surface and a second surface; Forming a semiconductor laminate structure on the first surface of the substrate; And forming a refractive index control layer on the second surface of the substrate, wherein the refractive index control layer has a refractive index of a middle value between the refractive index of the semiconductor laminate structure and the air refractive index, and a pattern is formed.

In one embodiment, the step of forming the refractive index control layer to form the pattern on the refractive index control layer by pressing the nano imprint mold, the pattern includes a plurality of nanostructures.

 In one embodiment, the refractive index control layer may include a nano imprint resin, photo-resist, poly-imide, sol-gel, spin-on-grass material or a mixture thereof.

The forming of the refractive index adjusting layer may include depositing a metal oxide having a rock salt structure on the second surface of the substrate to form the refractive index adjusting layer, wherein the pattern is formed of the metal oxide. It may include a number of pyramid structures spontaneously generated during the deposition process.

Further, forming the refractive index control layer may include depositing the metal oxide by electron beam deposition, sputtering, or thermal deposition.

Further, in an embodiment of the present invention, a pattern is formed on the surface of the refractive index control layer by using an electron beam, an interference patterning, or an ion beam lithography method. It may further comprise the step of forming.

In this case, the refractive index control layer is a metal represented by M _x M ' _1-x O (x≤1, M = Mg, one of Ca, Zn, Ni, M' = Be, Ca, Sr, Ba) It may include one or more metal oxide layers formed by depositing an oxide. In addition, the metal oxide includes impurities doped on the surface, and the impurities include B, In, Zn, Tl, Al, Sn, Ga, Te, Si, C, Ge, N, P, As, Sb, Bi , S, Se, Br, I, Ti and compounds comprising one or more thereof.

Before forming the refractive index control layer, the second surface of the substrate is surface treated using oxygen plasma, nitrogen plasma, or UVO.

The forming of the semiconductor laminate structure may include forming a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer in sequence, and removing the second conductive semiconductor layer and a part of the active by etching to form the first conductive semiconductor layer. And exposing a portion of the conductive semiconductor layer, wherein a transparent electrode layer is formed in the second conductive semiconductor layer, and a first electrode pad and a second electrode are exposed in the exposed region and the transparent electrode layer of the first conductive semiconductor layer. Electrode pads are formed respectively.

In example embodiments, a sapphire substrate including a pattern having a plurality of convex portions formed on the first surface may be prepared in the preparing of the substrate, and the semiconductor laminate structure formed in the forming of the semiconductor laminate structure may include And a gallium nitride based semiconductor layer formed on the pattern.

According to the present invention, a refractive index control layer including a pattern capable of improving light extraction efficiency is simply and easily formed on the lower surface of the substrate of the light emitting diode, so that a high efficiency light emitting diode can be manufactured easily and at low cost. Other advantages or effects of the present invention will be understood from the description of the following embodiments in more detail.

1 is a cross-sectional view showing a light emitting diode according to an embodiment of the present invention;
FIG. 2 is a graph showing a change in light extraction efficiency according to a change in refractive index of a substrate underlayer in the light emitting diode structure shown in FIG.
3 to 7 are cross-sectional views illustrating a method of manufacturing a light emitting diode according to an embodiment of the present invention.
8 is a scanning microscope photograph showing the pattern of the refractive index control layer formed by the nano-imprint mold in an embodiment of the present invention,
9 is a cross-sectional view showing a light emitting diode according to another embodiment of the present invention;
FIG. 10 is a scanning microscope photograph showing a pattern of metal oxides applied as a refractive index adjusting layer under a substrate of the light emitting diode of FIG. 9.
FIG. 11 is a scanning electron microscope (SEM) photograph showing pyramidal pattern structures according to a thickness of a refractive index control layer formed in MgO deposition.
FIG. 12 is a view showing the normalized light output of a horizontal light emitting diode including a refractive index controlling layer by depositing MgO and a light emitting diode having a conventional sapphire substrate.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided as examples for allowing a person skilled in the art to sufficiently convey the idea of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, and the like of the components may be exaggerated for convenience.

1 is a cross-sectional view illustrating a light emitting diode according to an exemplary embodiment of the present invention.

Referring to FIG. 1, a light emitting diode according to an embodiment of the present invention includes a sapphire substrate 1 having a light transmissive property, a semiconductor laminate structure 2, and a refractive index control layer 3. In addition, the light emitting diode includes a transparent electrode layer 4, a first electrode pad 5, and a second electrode pad 6.

The substrate 1 comprises an upper surface (or a first surface) and a lower surface (ie a second surface) opposite thereto. The upper surface of the substrate 1 is formed with a pattern 11 made of convex portions or concave to improve the light extraction efficiency, the sapphire substrate with the above pattern is called a patterned sapphire substrate (PSS).

The semiconductor laminate structure 2 is formed on the upper surface of the substrate 1 having the above-described pattern 11, and the refractive index adjusting layer 3 described in detail below is formed on the lower surface of the sapphire substrate 1. . Although not shown, the sapphire substrate 1 may be a PSS (Patterned Sapphire Substrate) having a predetermined concave-convex pattern formed on an upper surface thereof, that is, an interface with the semiconductor laminate structure 2.

The semiconductor laminate 2 includes a gallium nitride-based first conductive semiconductor layer 22, an active layer 24, and a second conductive semiconductor layer 26 grown using the substrate 1 as a growth substrate. can do. A buffer layer 21 may be formed between the substrate 1 and the first conductive semiconductor layer 22 to mitigate lattice mismatch. The active layer 24 is interposed between the first conductive semiconductor layer 22 and the first conductive semiconductor layer 26.

The first conductivity-type semiconductor layer 22 is a layer formed adjacent to the substrate 1 and may be an n-type semiconductor layer. In addition, the second conductivity-type semiconductor layer 26 is a layer relatively far from the sapphire substrate 1 and may be a p-type semiconductor layer. Conversely, the first conductive semiconductor layer 22 may be a p-type semiconductor layer and the second conductive semiconductor layer 26 may be an n-type semiconductor layer.

The first conductive semiconductor layer 22, the active layer 24, and the second conductive semiconductor layer 26 may be formed of a gallium nitride-based compound semiconductor material, that is, (Al, In, Ga) N. The active layer 24 has a composition element and composition ratio determined so as to emit light of a required wavelength such as ultraviolet light or blue light. The first conductive semiconductor layer 22 and / or the second conductive semiconductor layer 26 may be formed as a single layer, as shown, but may be formed in a multilayer structure. In addition, the active layer 24 may be formed of a single quantum well or multiple quantum well structures. A buffer layer 21 may be interposed between the sapphire substrate 1 and the first conductivity type semiconductor layer 22 to mitigate lattice mismatch.

The light emitting diode according to the present exemplary embodiment is a horizontal light emitting diode having both the first electrode pad 5 and the second electrode pad 6 thereon, and exposes the upper portion of the first conductive semiconductor layer 22 to expose it. In order to form the first electrode pad 5 in the formed region, the semiconductor laminate structure 2 has a structure in which some regions of the second conductive semiconductor layer 26 and the active layer 24 are removed. The first electrode pad 5 is formed in the upper exposed region of the first conductive semiconductor layer 22, and the second electrode pad 6 is formed on the second conductive semiconductor layer 26.

As illustrated, the transparent electrode layer 4 may be formed on the second conductive semiconductor layer 26, and the second electrode pad 6 may be formed on the transparent electrode layer 4. The transparent electrode layer 4 is formed of, for example, ITO or Ni / Au, and has a specific resistance lower than that of the second conductive semiconductor layer 26 to distribute current.

The refractive index control layer 3 is formed on the lower surface of the substrate 1 and may have a refractive index substantially equal to 1.775, which is the refractive index of the substrate 1. In addition, the refractive index control layer 3 includes a pattern made of nanostructures 32, which is formed by nanoimprint. When the refractive index adjusting layer 3 is formed under the substrate 1 at the same refractive index as the substrate 1 in the light emitting diode structure shown in FIG. 1, as shown in the graph of FIG. It becomes 64%, and compared with the case where the lower surface of the said board | substrate 1 is in direct contact with the air of refractive index 1, about 20% efficiency improves. The refractive index adjusting layer 3 increases light extraction efficiency almost linearly as its refractive index is larger than the refractive index of air, and exhibits the maximum light extraction efficiency when the refractive index matches the sapphire substrate.

In addition, the refractive index control layer 3 includes nanostructures 32 formed by nanoimprint on the lower side of the substrate 1 in contact with air and the light is emitted, the nanostructures 32 are incident light Scattering more allows more light to be emitted to the outside.

Referring to FIGS. 3 to 5, a light emitting diode manufacturing method according to an exemplary embodiment of the present invention will be described.

First, referring to FIG. 3, a patterned sapphire is formed on the upper surface of the substrate 1, for example, by using a gallium nitride-based first conductive semiconductor layer 22, an active layer 24, and a MOCVD or MBE technique. The second conductive semiconductor layer 26 is formed in sequence. The thickness of the sapphire substrate 1 is preferably 100 µm to 400 µm, most preferably 150 µm or less. A process of reducing the thickness of the sapphire substrate 1 to 150 μm or less through a lapping process may be used. The lapping process may be performed after the formation of the semiconductor laminate structure, in particular immediately before the process of forming the refractive index adjusting layer 3 to be described below. As mentioned above, a buffer layer 21 having a single layer or a multilayer structure may be formed between the sapphire substrate 1 and the first conductive semiconductor layer 22.

Next, referring to FIG. 4, some regions of the second conductivity-type semiconductor layer 22 and the active layer 24 are etched away using a photo and an etching technique, so that some regions 222 of the first conductivity-type semiconductor layer 22 are etched away. ) To the top.

Next, referring to FIG. 5, for example, ITO or Ni / Au is deposited on the upper surface of the second conductive semiconductor layer 26 to form the transparent electrode layer 4, and the upper surface of the transparent electrode layer 4 and the first conductive layer. The second electrode pad 6 and the first electrode pad 5 are formed in each of the exposed regions 222 of the type semiconductor layer 22.

In this case, the transparent electrode layer 4 is formed immediately after the formation process of the first conductive semiconductor layer 22, the active layer 24 and the second conductive semiconductor layer 26 described in FIG. Note that some regions may be formed together with the second conductivity-type semiconductor layer 26 and the active layer 24 by mesa etching and photolithography to expose the upper portion of the semiconductor layer 22. .

Next, the refractive index adjusting layer 3 is formed on the lower surface of the sapphire substrate 1 by the nano imprint method as shown in FIGS. 6 and 7. Note that in FIG. 6 and FIG. 7, the lower surface of the sapphire substrate 1 faces upward unlike the other figures.

First, referring to FIGS. 6 and 7, a nano imprint resist layer 3 ′ is formed on a lower surface of the sapphire substrate 1 by, for example, spin coating, and is manufactured in advance to have a nano pattern. ) Is pressed onto the nanoimprint resist layer 3 'to transfer the nanopattern to the nanoimprint resist layer 3'. Next, UV or heat is applied to cure the nanoimprint resist layer 3 ′, and the nanoimprint mold M is separated to form a refractive index control layer 3 including a nanopattern having nanostructures on the sapphire substrate 1. On the lower surface of the

Formation of the refractive index control layer 3 by nanoimprinting is performed by spin coating and doctor by using a material such as imprint resin, photo-resist, poly-imide sol-gel, spin-on-glass, or a mixture containing such materials. Through the blade, bar coating method, etc., the nano-pattern can be easily and efficiently formed.

FIG. 8 is a scanning electron micrograph showing a pattern of the refractive index adjusting layer 3 after nanoimprinting, and using light patterning technique using nanoimprint from FIG. 8, without using separate wet etching and dry etching, It can be seen that the refractive index control layer including the nanopattern for efficiency improvement can be easily formed.

As described above, by using the nanoimprint method, a refractive index control layer having a thin structure can be formed on the lower surface of the substrate of the light emitting diode with little time and cost without etching the substrate, thereby providing high light extraction efficiency. It is possible to implement a light emitting diode having. The nanoimprint method is suitable for manufacturing large area light emitting diodes and can be immediately applied to the manufacturing process of large area light emitting diodes.

9 is a cross-sectional view for describing a light emitting diode according to another embodiment of the present invention.

Referring to FIG. 9, the light emitting diode according to the present embodiment has a semiconductor stacked structure 2 formed on an upper surface of the sapphire substrate 1, that is, a first surface, similarly to the previous embodiment. The refractive index adjusting layer 3a is formed on the lower surface, that is, the second surface. The configuration of the foregoing embodiment of the sapphire substrate 1 and the semiconductor laminated structure 2 can be followed as it is, and therefore description is omitted to avoid duplication.

The refractive index adjusting layer 3a is made of a metal oxide having a rock salt structure, unlike the refractive index adjusting layer described in the above embodiments. Such metal oxides include MgO based, CaO based, NiO based, and ZnO based. And the like. Such metal oxides are deposited on the lower surface of the sapphire substrate 1, for example, in electron beam deposition, sputtering or thermal deposition, in the course of which a number of pyramidal protrusions 32a (hereinafter " pyramid structures ") are spontaneously formed. Referring to FIG. 10, scanning micrographs of patterns of metal oxides, ie, MgO, CaO, and NiO, which are applied as a refractive index adjusting layer under the sapphire substrate are shown.

For example, the MgO layer applied as the refractive index control layer 3a has a refractive index (n = 1.74) that is almost the same as that of a sapphire substrate having a refractive index of n = 1.77. In addition, the refractive index of the MgO layer as described above corresponds to the median between the refractive index (n = 2.5) and the air refractive index (n = 1) of the gallium nitride-based semiconductor, the MgO refractive index control layer (3a) cooperates with the sapphire substrate (1) To act as a refractive index adjusting layer. The metal oxide layers listed above also have a refractive index similar to that of the MgO layer.

The refractive index control layer 3a may also scatter light by the pyramid structure 32a formed in the deposition process without any additional process in the deposition process of the metal oxide to emit more light scattered to the outside. The thickness of the refractive index control layer (3a) and the pattern thickness of the pyramid structure (32a) may be substantially the same or similar, it is preferably set within about 5000 ~ 4㎛.

However, the present invention is not limited thereto, and after depositing the refractive index control layer 3a, an electron beam, interference patterning, or ion beam lithography method is applied to the refractive index control layer 3a. It is also possible to form a pattern on the surface using.

Referring to the method of forming the above-described refractive index control layer using a metal oxide as follows.

A metal oxide is deposited to a predetermined thickness on the lower surface of the sapphire substrate 1 before or after formation of the semiconductor laminate structure 2. At this time, it is preferable to perform a surface treatment to increase the deposition affinity of the metal oxide with respect to the surface to be deposited of the sapphire substrate 1, such surface treatment is oxygen plasma treatment, nitrogen plasma treatment, UVO (Ultra Violet Ozone) treatment, etc. This can be used.

Figure 11 shows the shape of the pyramid structures according to the thickness of the refractive index control layer when depositing MgO to form a refractive index control layer. Referring to this, the structure and shape of the pyramid pattern changes depending on the MgO deposition thickness, and thus, by controlling the deposition thickness, it is possible to obtain a pyramid pattern of the intended structure. In addition to the MgO-based oxides, other oxides of the rock salt structures listed above have the same aspect.

The MgO-based oxide used to form the refractive index control layer may be a ternary or more poly-based oxide obtained by adding one or more elements to MgO.

As the MgO-based ternary compound, for example, Mg _x Be _1-x O (x ≦ ₁ ), Mg _x Ca _1-x O (x ≦ ₁ ), Mg _x Sr _1-x O (x ≦ ₁ ), Mg _x There may be Ba _1-x O (x ≦ ₁ ).

In addition, as the MgO-based multicomponent compound, two or more elements among Be, Ca, Sr, and Ba elements may form a compound with Mg.

In addition, the MgO-based oxide may include doped impurities on the surface, and the impurities used may include B, In, Zn, Tl, Al, Sn, Ga, Te, Si, C, Ge, N, P, There may be oxides of As, Sb, Bi, S, Se, Br, I, Ti or their metals.

In addition to the MgO-based oxide, other oxides may be formed of ternary or higher poly-based oxides as described above.

Thus, the metal oxide of the rock salt structure represented by M _x M ' _1-x O (x≤1, M = Mg, Ca, Zn, Ni, at least one of M' = Be, Ca, Sr, Ba) is The bottom surface of the sapphire substrate may be deposited (especially electron-beam deposition) to form a refractive index adjusting layer comprising a pattern having a plurality of pyramid structures as described above. One metal oxide layer formed by depositing the above metal oxide may constitute a refractive index adjusting layer, but two or more kinds of metal oxide layers may constitute the refractive index adjusting layer.

FIG. 12 shows the normalized light output of a horizontal light emitting diode including a refractive index controlling layer by depositing MgO and a light emitting diode having a conventional sapphire substrate. In the case of the light emitting diode to which the MgO refractive index control layer was applied, the light output was measured after different thicknesses of 0, 0.2, 0.7, 2, and 4 μm of the MgO layer were deposited on the lower surface of the sapphire substrate. In the absence of the MgO layer, when the thickness 0 was used as a reference, the light output increased to 12.9% at 0.2 μm and 10.1% at 0.7 μm.

The pyramid pattern formed by the above-described metal oxide deposition can be fabricated using general optical lithography patterning without using electron beam lithography patterning, which is expensive and difficult to apply to large-area wafer processes. For this reason, it is very effective in terms of large-area application and manufacturing cost since it is characterized in that no additional process other than the deposition process is required.

1: Sapphire Substrate 2: Semiconductor Laminated Structure
3, 3a: refractive index adjusting layer 22: first conductive semiconductor layer
24: active layer 26: second conductive semiconductor
32: nanostructure 32a: pyramid structure

Claims (19)

In the light emitting diode,
A translucent substrate comprising a first side and a second side;
A semiconductor stacked structure comprising a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, the semiconductor stacked structure formed on a first surface of the substrate; And
And a refractive index control layer formed to have a pattern on the second surface of the substrate. The light emitting diode of claim 1, wherein the refractive index control layer is formed by nanoimprinting so that the pattern has a plurality of nanostructures. The light emitting diode of claim 1, wherein the refractive index control layer is formed by deposition of a metal oxide having a rock salt structure, and the pattern includes a plurality of pyramid structures. The method of claim 3, wherein the refractive index adjusting layer is M _× M ′ _1-x O (x ≦ ₁ , M = Mg, Ca, Zn, Ni, at least one of M ′ = Be, Ca, Sr, Ba). A light emitting diode comprising at least one metal oxide layer formed by depositing a metal oxide to be displayed. The method of claim 4, wherein the metal oxide includes impurities doped on a surface, and the impurities include B, In, Zn, Tl, Al, Sn, Ga, Te, Si, C, Ge, N, P, As, Sb. , Bi, S, Se, Br, I, Ti and a light emitting diode, characterized in that selected from the group consisting of one or more thereof. The light emitting diode of claim 1, wherein a pattern including a plurality of convex portions is formed on a first surface of the substrate, and a semiconductor laminate structure is formed on the pattern. The light emitting diode according to any one of claims 1 to 6, wherein the substrate comprises a sapphire substrate and the semiconductor stack structure comprises a gallium nitride based semiconductor. The method according to any one of claims 1 to 6,
A transparent electrode layer;
A first electrode pad; And
Further comprising a second electrode pad,
The first conductivity type semiconductor layer has a region exposed by removing a portion of the second conductivity type semiconductor layer and the active layer,
The transparent electrode layer is formed on the second conductive semiconductor layer,
The first electrode pad is formed in the exposed area of the first conductive semiconductor layer,
The second electrode pad is a light emitting diode, characterized in that formed on the transparent electrode layer. In the manufacturing method of the light emitting diode,
Preparing a light transmissive substrate having a first side and a second side;
Forming a semiconductor laminate structure on the first surface of the substrate; And
Forming a refractive index control layer on a second surface of the substrate,
The refractive index control layer has a refractive index between the refractive index and the air refractive index of the semiconductor laminate structure, characterized in that the pattern is formed. The method of claim 9, wherein the forming of the refractive index control layer comprises forming the pattern on the refractive index control layer by pressing the nanoimprint mold, wherein the pattern includes a plurality of nanostructures. . The method of claim 10, wherein the refractive index control layer comprises nanoimprint resin, photo-resist, poly-imide, sol-gel, spin-on-grass material, or a mixture thereof. The method of claim 9, wherein the forming of the refractive index adjusting layer comprises depositing a metal oxide having a rock salt structure on the second surface of the substrate to form the refractive index adjusting layer, wherein the pattern is a deposition of the metal oxide. Light emitting diode manufacturing method comprising a plurality of pyramid structures spontaneously generated in the process. The method of claim 12, wherein the forming of the refractive index control layer comprises depositing the metal oxide by electron beam deposition, sputtering, or thermal deposition. The method of claim 12, further comprising forming a pattern on the surface of the refractive index control layer using an e-beam, an interference patterning method, or an ion beam lithography method. Light emitting diode manufacturing method characterized in that. The method of claim 12, wherein the refractive index adjusting layer is M _x M ' _1-x O (x≤1, M = Mg, Ca, Zn, Ni, at least one of M' = Be, Ca, Sr, Ba) A light emitting diode manufacturing method comprising at least one metal oxide layer formed by depositing a metal oxide to be displayed. The method of claim 15, wherein the metal oxide includes impurities doped on a surface, and the impurities include B, In, Zn, Tl, Al, Sn, Ga, Te, Si, C, Ge, N, P, As, Sb. , Bi, S, Se, Br, I, Ti and a method for manufacturing a light emitting diode, characterized in that selected from the group consisting of one or more of these. The method of claim 9, wherein before the forming of the refractive index control layer, the second surface of the substrate is surface treated using oxygen plasma, nitrogen plasma, or UVO. The method of claim 9, wherein the forming of the semiconductor stacked structure comprises sequentially forming a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, and etching the second conductive semiconductor layer and a part of the active layer by etching. Removing a portion of the first conductive semiconductor layer to expose a portion of the first conductive semiconductor layer, wherein a transparent electrode layer is formed on the second conductive semiconductor layer, and a first region is exposed on the exposed region and the transparent electrode layer of the first conductive semiconductor layer. A light emitting diode manufacturing method, characterized in that the electrode pad and the second electrode pad is formed respectively. The method of claim 9, wherein in the preparing of the substrate, a sapphire substrate including a pattern having a plurality of convex portions formed on the first surface is prepared, and the semiconductor laminate structure is formed. The semiconductor stack structure comprises a gallium nitride based semiconductor layer formed on the pattern.

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