KR101615564B1 - Manufacturing method for vertical-light emitting diode and vertical-light emitting diode - Google Patents

Abstract

The present invention relates to a vertical type light emitting diode and a method of manufacturing the same. The vertical light emitting diode according to the present invention is based on a nitride semiconductor having a pn junction structure and forms a transparent material layer having a pattern structure different in refractive index from the p-type clad layer on the p-type clad layer. On the transparent material layer, a reflective metal electrode layer is formed as a p-electrode. A pattern is formed on the p-electrode by forming a three-dimensional pattern on the transparent material layer and then depositing the p-electrode. The light emitted from the active layer is emitted at a wide radiation angle by the pattern formed on the p-electrode, and the reflectance is improved according to the patterned shape and the refractive index of the material.
The vertical type light emitting diode according to the present invention is manufactured by a simple process, and the light is emitted at a wide angle by the pattern of the p-electrode, thereby providing a highly efficient vertical light emitting diode with high reflection efficiency.

Description

[0001] The present invention relates to a vertical-type light-emitting diode (LED)

The present invention relates to a vertical type light emitting diode manufacturing method and a vertical type light emitting diode, and more particularly, to a method of manufacturing a vertical type light emitting diode based on a nitride semiconductor having a pn junction structure, Forming a transparent material layer having a different refractive index from each other, forming a pattern on the transparent material layer, and forming a reflective metal electrode layer as a p-electrode on the transparent material layer having the pattern formed thereon, The present invention relates to a method of manufacturing a vertical type light emitting diode and a vertical type light emitting diode in which a pattern is formed on a p-electrode by a structure to increase a reflectance of light and realize a wide radiation angle.

LEDs are devices that convert electrical signals into light using the characteristics of semiconductors. Since the development of LEDs that emit red light in 1962, LEDs have been developed that emit various colors of light ranging from infrared, visible, and ultraviolet . In particular, vertical LEDs are being used in various fields because they can extract ultraviolet rays safely and at low cost.

Generally, LEDs have a conversion efficiency of 40% or more, and the remaining energy is converted into heat energy. Therefore, in order to solve the problem of heat dissipation of the LED, many LEDs having a vertical electrode structure are used. Korean Patent No. 10-0705225 discloses a method of manufacturing a vertical type light emitting device. The vertical light emitting device includes a light emitting structure and a pair of electrodes sequentially stacked. However, the p-electrode used as the reflective electrode has a problem that the surface is flat and the light is mainly reflected only in the vertical direction and the radiation angle is narrow.

Therefore, it is necessary to develop a high efficiency vertical type LED capable of increasing the light extraction efficiency by dispersing the radiation angle of the emitted light in the horizontal direction to increase the radiation angle.

Patent Document 1: Korean Patent No. 10-0705225 (Registered on April 4, 2007)

An object of the present invention is to provide a vertical type light emitting diode having a high light emitting efficiency by increasing the reflectance and the radiation angle of light emitted from a vertical type light emitting diode and a method of manufacturing the same.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vertical type light emitting diode capable of improving the reflectance with various patterns and adjusting the radiation angle as needed, and a method of manufacturing the same.

In accordance with an aspect of the present invention, there is provided a method of fabricating a vertical type light emitting diode based on a nitride semiconductor having a pn junction structure, comprising the steps of: forming a p- Forming a transparent material layer having a different refractive index from the transparent material layer, forming a pattern on the transparent material layer, and forming a reflective metal electrode layer as a p-electrode on the transparent material layer having the pattern formed thereon.

In the vertical type light emitting diode manufacturing method according to another embodiment of the present invention, the transparent material layer is formed to have a thickness of 10 nm or more and 15 m or less.

In the vertical type light emitting diode manufacturing method according to another embodiment of the present invention, the transparent material layer is deposited on the entire upper surface of the p-type cladding layer, and the pattern structure formed on the transparent material layer has a difference between the minimum thickness and the maximum thickness of 10 nm or more and 10 m or less .

In the method of manufacturing a vertical type light emitting diode according to another embodiment of the present invention, the transparent material layer is partially deposited on the p-type cladding layer, and the thickness of the pattern structure formed on the transparent material layer may be 10 nm or more and 10 m or less.

In the method of fabricating a vertical type light emitting diode according to another embodiment of the present invention, the transparent material layer may include at least one of ITO, ZnO, MgO, SnO, In ₂ O ₃ , Ga ₂ O ₃ , BeO, SiO ₂ , Si ₃ N ₄ , ₂ O, WO ₃ , TiO ₂ , AgO, Ag ₂ O, a metal oxide group of NiO, or a nitride group of AlN, InN, or BN.

In the vertical type light emitting diode manufacturing method according to another embodiment of the present invention, the pattern structure of the transparent material layer may be formed in a regular arrangement.

In the vertical type light emitting diode manufacturing method according to another embodiment of the present invention, the pattern structure of the transparent material layer may be circular or polygonal.

In the vertical type light emitting diode manufacturing method according to another embodiment of the present invention, the pattern structure of the transparent material layer may be in the form of a straight line or a lattice.

In the vertical type light emitting diode manufacturing method according to another embodiment of the present invention, the pattern structure of the transparent material layer may be formed in an irregular arrangement in which at least two pattern shapes are mixed.

The reflective metal electrode layer may be formed of at least one metal selected from the group consisting of Ag, Al, In, Ti, Ni, Cu, Cr, Au, Pd, W, and Pt in the method of manufacturing a vertical LED according to another embodiment of the present invention .

The vertical type light emitting diode according to the embodiment of the present invention can be manufactured by a vertical type light emitting diode manufacturing method.

The vertical type light emitting diode and the method of manufacturing the same according to the present invention increase the reflectance of light and increase the radiation angle of emitted light by forming a pattern on the p-electrode, increase the reflection of light due to difference in refractive index, Emitting efficiency of the diode can be increased.

The vertical type light emitting diode and the method of manufacturing the same of the present invention can form a pattern on the p-electrode in various shapes to adjust the radiation angle as needed.

1 (a) and 1 (b) are schematic views showing a vertical type light emitting diode according to an embodiment of the present invention.
2 is a view illustrating light emission in a vertical type light emitting diode according to an embodiment of the present invention.
3A to 3M are views illustrating a process of forming each layer of a light emitting diode in a vertical type light emitting diode according to an embodiment of the present invention.
4A and 4B are views showing the shape of a p-electrode according to another embodiment of the present invention when the shape of the transparent material layer is elliptical in the vertical type light emitting diode.
5A and 5B are views showing the shape of a p-electrode according to another embodiment of the present invention when the shape of a pattern of a transparent material layer is a quadrangular pyramid shape in a vertical type light emitting diode.
6 (a) and 6 (b) are views showing the shape of a p-electrode according to another embodiment of the present invention when the pattern of the transparent material layer in the vertical type light emitting diode has a quadrangular pyramid shape.
7A and 7B are views showing the shape of a p-electrode according to another embodiment of the present invention when the shape of the pattern of the transparent material layer is a straight shape.
8A to 8D are views showing various pattern shapes of a transparent material layer in a vertical type light emitting diode according to another embodiment of the present invention.
9 is a view showing a case where the shape of the pattern of the transparent material layer in the vertical type light emitting diode according to another embodiment of the present invention is irregular.
10 (a) and 10 (b) are views showing a deposition form of a transparent material layer according to an embodiment of the present invention.
11 is a view showing that a transparent material layer is partially deposited on a p-type cladding layer in a vertical type light emitting diode according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that, in the drawings, the same components are denoted by the same reference symbols as possible. Further, the detailed description of known functions and configurations that may obscure the gist of the present invention will be omitted. For the same reason, some of the components in the drawings are exaggerated, omitted, or schematically illustrated.

FIG. 1 is a schematic view of a vertical type light emitting diode according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a vertical type light emitting diode according to an embodiment of the present invention. FIG.

1, a vertical light emitting diode 1000 according to an embodiment of the present invention includes a carrier 1100, a p-electrode 1200, a transparent material layer 1300, a p-type cladding layer 1400, An active layer 1500, an n-type cladding layer 1600, and an n-electrode 1700.

The p-electrode 1200 is located on the carrier 1100. The p-electrode 1200 is formed of a reflective metal electrode. The p-electrode 1200 is formed of a metal oxide group such as ITO, ZnO, Ga ₂ O ₃ , MgO, MgZnO, ZnGaO, and a metal oxide such as In, Sn, Ag, Au, Al, Ti, Ni, Cu, Cr, Ru, Sn, Ag, Au, Al, Ti, Ni, Zn, and the like, which are formed of a metal oxide or a metal selected from metal oxides such as ITO, ZnO, Ga ₂ O ₃ , MgO, MgZnO, ZnGaO, Cu, Cr, Ru, Pd, W, Pt, or the like, or an alloy of two or more metals.

The p-electrode 1200 may be thermally treated at a temperature of 100 to 700 ° C in a vacuum or a nitrogen or oxygen atmosphere. In this embodiment, the p-electrode 1200 serves as a reflective metal electrode. However, the p-electrode 1200 may further include a reflective layer in addition to the p-electrode 1200 forming the ohmic electrode. The p-electrode and the reflective layer may be formed of a single metal such as Ag, Al, Ni, Cu, Cr, Au, Cr, Pd, or an alloy of these metals.

The p-electrode 1200 has a pattern formed thereon. For example, a hemispherical pattern pattern may be formed on the upper surface of the p-electrode 1200. As shown in FIG. 2, as the light is reflected by the pattern formed on the p-electrode 1200, the angle at which the light is emitted is widened, and the radiation angle of the light emitting diode is widened. Since the transparent material having a refractive index difference is used for patterning, the reflectance can also be increased.

On the p-electrode 1200, a transparent material layer 1300 is located. The GaN-based material has a refractive index of about 2.35. When light is emitted to the outside of the light emitting diode, the light is not totally reflected within the light emitting diode but is emitted to the outside. For this, in the present invention, a pattern is formed on the p-electrode 1200 to reflect light at various angles at the p-electrode 1200, that is, the reflection electrode, thereby widening the angle at which light is emitted. The transparent material layer 1300 is for patterning the p-electrode 1200, and is patterned into various shapes as needed. The transparent material layer 1300 has a thickness of several tens of nanometers to several tens of micrometers and may be formed of ITO, ZnO, Ga ₂ O ₃ , NiO, Cu ₂ O, CuO, or the like. The transparent material layer 1300 is patterned in a three-dimensional shape by etching. The refractive index of the transparent material layer 1300 is different from the refractive index of the p-type cladding layer to be described later.

In addition to the conductive material such as the transparent electrode, the oxide can be applied to form a pattern only in a part of the p-layer. In this case, in addition to the conventional conductive transparent electrode, patterning can be performed using a nonconductive transparent material. As the nonconductive transparent material, materials such as SiO ₂ , Al ₂ O ₃ , and AlN can be used.

The p-type cladding layer 1400 is located on the transparent material layer 1300 and the active layer 1500 is located on the p-type cladding layer 1400. An n-type cladding layer 1600 is located on the active layer 1500. The upper surface of the n-type cladding layer 1600 may have a texturing structure, thereby enhancing light extraction efficiency.

An n-electrode 1700 is deposited on the n-type cladding layer 1600. The n-electrode 1700 may be formed of a metal such as Ti, Cr, or Al or a transparent electrode such as ITO or ZnO. an ohmic contact layer may be formed between the n-type cladding layer 1600 and the n-electrode 1700. [

A bonding pad (not shown) for wire bonding is formed on the p-electrode 1200 and the n-electrode 1700.

3A to 3M are views illustrating a process of forming each layer of a light emitting diode in a vertical type light emitting diode according to an embodiment of the present invention.

In order to manufacture a vertical type light emitting diode according to the present invention, a buffer layer 1020 is deposited on a substrate 1010, as shown in FIG. As the substrate 1010, silicon (Si), silicon carbide (SiC), sapphire (Al ₂ O ₃ ), gallium arsenide (GaAs), or the like is generally used. In this embodiment, a sapphire substrate is used as the substrate 1100. The sapphire substrate is advantageous in light extraction efficiency and durability. In this embodiment, a sapphire substrate is used as the substrate 1100, but not limited thereto, and various substrates can be used.

A buffer layer 1020 is formed on the substrate 1010. The buffer layer 1020 is used as a layer to buffer the stress between the substrate and the layer grown thereon. A buffer layer 1020 is formed on the substrate 1010 for lattice match. In the process of growing the metal layer on the substrate 1010, the lattice constants between the substrate and the layer to be grown are inconsistent. In this case, defects such as dislocation may occur and the crystal quality may be lowered. Such a defect can be reduced by the buffer layer 1020.

Next, as shown in FIG. 3B, an n-type cladding layer 1600 is deposited on the buffer layer 1020. The n-type cladding layer 1600 is formed mainly of GaN or AlGaN.

An active layer 1500 is formed on the n-type cladding layer 1600 (Fig. 3C). The active layer 1500 is a layer in which electrons and holes are recombined to generate light. The wavelength of light emitted from the light emitting diode is determined according to the kind of the material of the active layer 1500 and the thickness of the active layer 1400.

As shown in FIG. 3D, a p-type cladding layer 1400 is deposited on the active layer 1500. The p-type cladding layer 1400 may be formed of a material such as GaN or AlGaN.

As shown in FIG. 3E, a transparent material layer 1300 is deposited on the p-type cladding layer 1400 to form a pattern of the p-electrode 1200. The refractive index of the material forming the transparent material layer 1300 is different from the refractive index of the p-type cladding layer 1400. The transparent material layer 1300 may be deposited using sputtering, electron beam, laser beam, or the like. The thickness of the transparent material layer 1300 to be deposited may be 10 nm to 15 占 퐉. Transparent material layers 1300 are _{ITO, ZnO, Ga 2 O 3} , NiO, Cu 2 O, CuO, MgO, SnO, In 2 O 3, BeO, SiO 2, Si 3 N 4, WO 3, TiO 2, AgO , Ag ₂ O, or a nitride group of AlN, InN, or BN, or a combination of two or more of these alloys. The transparent material layer 1300 is patterned into various shapes for patterning the p-electrode 1200.

As shown in FIG. 3F, a photoresist 1320 is applied on the transparent material layer 1300 to form a pattern in the transparent material layer 1300. The mask pattern 1340 is placed on the upper surface of the transparent material layer 1300 coated with the photoresist 1320 and irradiated with ultraviolet rays (FIG. 3G). The exposed transparent material layer 1300 is wet-etched to further etch portions of the transparent material layer 1300 from which the photoresist 1320 has been removed to form a three-dimensional pattern on the transparent material layer 1300 as a pattern on the photoresist 1320 (Fig. 3H and Fig. 3I). The thickness difference between the thinnest portion and the thickest portion in the three-dimensional pattern of the transparent material layer 1300 may be 10 nm to 10 μm.

As shown in Figure 3i, the transparent material layer 1300 is embossed and etched in a hemispherical shape. A p-electrode 1200 is deposited over the transparent material layer 1300 (Fig. 3J). The p-electrode 1200 is formed of a metal or alloy such as Ag, Au, Ni, Ru, Ir, Ni, Cu, or Cr. The p-electrode 1200 is a reflective metal electrode that forms an ohmic electrode and reflects light emitted from the active layer. After the p-electrode 1200 is formed, heat treatment may be performed at 100 to 700 ° C in a nitrogen or oxygen atmosphere or a vacuum atmosphere. Although the p-electrode 1200 serves as a reflective metal electrode in this embodiment, a p-electrode 1200 forming the ohmic electrode may be formed, and then a reflective layer may be further provided on the p-electrode 1200. The p-electrode and the reflective layer may be formed of a single metal such as Ag, Al, Ni, Cu, Cr, Au, Cr, or Pd or an alloy of these metals.

In addition, as the transparent material layer 1300, in addition to a conductive material such as a transparent electrode, an oxide can be applied so that a pattern can be formed only in a part of the p-layer. In this case, in addition to the conventional conductive transparent electrode, patterning can be performed using a nonconductive transparent material. As the nonconductive transparent material, materials such as SiO ₂ , Al ₂ O ₃ , and AlN can be used.

The p-electrode 1200 is formed on the transparent material layer 1300 in which the three-dimensional pattern is formed, so that the p-electrode 1200 has a curved shape at the interface between the p-electrode 1200 and the transparent material layer 1300. When the manufactured light emitting diode 1000 is reversed, the p-electrode 1200 has a depressed pattern since the transparent material layer 1300 has a relief shape. That is, as shown in FIG. 1, the p-electrode 1200 has a hemispherical engraved pattern, and the emitted light is reflected by the p-electrode 1200 in which the pattern is formed, and is emitted at a wider radiation angle.

A carrier 1100 is formed on the p-electrode 1200 (Fig. 3K). The carrier 1100 may be formed by a method of electroplating or electroless plating, or may be formed by sputtering or wafer bonding of a conductive substrate. The thickness of the carrier is 0.5 to 200 mu m.

Thereafter, the substrate 1010 is removed by a laser lift off (LLO) process. When the sapphire substrate 1010 is irradiated with a laser, the surface of the buffer layer 1020 made of gallium nitride is decomposed into gallium (Ga) and nitrogen gas (N ₂ ), and the substrate 1010 is separated. In this embodiment, the substrate 1010 is separated by a laser lift-off process, but a chemical lift off may be used. After the substrate 1010 is removed, the buffer layer 1020 is removed by etching.

The p-electrode 1200, the transparent material layer 1300, and the p-type cladding layer (not shown) are formed on the carrier 1100, as shown in FIG. 31, by reversing the light emitting diode from which the substrate 1010 and the buffer layer 1020 are removed. 1400, the active layer 1500, and the n-type cladding layer 1600 are sequentially stacked. By etching the buffer layer 1020, the surface of the exposed n-type cladding layer 1600 can be roughened to form a textured surface, and the light extraction efficiency of the vertical type light emitting diode can be enhanced through the texturing.

And the n-electrode 1700 is deposited on the n-type cladding layer 1600 of the inverted light emitting diode. The n-electrode 1700 may be formed of a metal such as Ti, Cr, or Al or a transparent electrode such as ITO or ZnO. The n-electrode 1700 is located on the uppermost layer of the inverted light emitting diode 1000. The n-electrode 1700 occupies a small area on the n-type cladding layer 1600, and the n-electrode 1700 is formed in ohmic contact to reduce the area occupied by the n-electrode 1700, A light emitting diode having good efficiency can be manufactured.

After forming the p-electrode 1200 and the n-electrode 1700, a bonding pad for wire bonding is formed on the p-electrode 1200 and the n-electrode 1700.

A passivation layer (not shown) made of an insulating material may be formed on the sidewall of the light emitting diode. The passivation layer protects the light emitting diode elements and prevents leakage of current from the side walls of the light emitting diode elements. The passivation layer may be formed by depositing SiO ₂ , Si _x N _y, or the like. The thickness of the passivation layer may be about 200 nm to 1 占 퐉. After the fabrication of the light emitting diodes is completed, the light emitting diodes are separated by dicing.

4 (a) and 4 (b) are views showing the shape of the p-electrode when the shape of the pattern of the transparent material layer in the vertical type light emitting diode according to another embodiment of the present invention is elliptical, 6A and 6B are views showing the shape of the p-electrode when the shape of the pattern of the transparent material layer is a quadrangular pyramid in the vertical type light emitting diode according to another embodiment of the present invention, 7A and 7B are views showing the shape of the p-electrode when the pattern of the transparent material layer in the vertical type light emitting diode according to another embodiment of the present invention is a quadrangular pyramid, FIGS. 8A to 8D are views showing the shape of the p-electrode when the shape of the pattern of the transparent material layer in the vertical type light emitting diode according to another embodiment of the present invention is a straight shape, In a vertical type light emitting diode according to another embodiment of the present invention, FIG. 9 is a view showing a case where a pattern of a transparent material layer is irregular in a vertical type light emitting diode according to another embodiment of the present invention. FIG.

As shown in FIG. 4 (a), the transparent material layer 1300 may be etched in an elliptical shape in the manufacturing process of the light emitting diode 1000. In the etching process of the transparent material layer 1300, the mask pattern is formed into an elliptic shape and exposed to form an elliptical three-dimensional pattern. The transparent material layer 1300 on which the elliptical photoresist 1320 is formed is etched by wet etching. At this time, the height of the three-dimensional pattern and the interval of the pattern array can be adjusted by controlling the etching time.

A p-electrode 1200 is deposited on a transparent material layer 1300 having an elliptical pattern. Since the p-electrode 1200 is directly laminated on the transparent material layer 1300, the interface with the transparent material layer 1300 is formed in three dimensions. That is, as shown in FIG. 4B, an elliptical relief pattern is formed on the p-electrode 1200 by an elliptical relief pattern formed on the transparent material layer 1300. The p-electrode 1200 is a reflective electrode, and the light emitted from the active layer is reflected by the pattern formed on the p-electrode 1200, so that not only the reflectance of the light emitting diode is high but also the light is dispersed in the horizontal direction.

The shape of the transparent material layer 1300 can be variously formed by adjusting the shape of the mask pattern and the material and the etching degree of the transparent material layer 1300. The shape and pattern of the transparent material layer 1300 The p-electrode 1200 having various patterns can be formed by the height and the interval formed. In this embodiment, wet etching is taken as an example, but the present invention is not limited thereto, and the transparent material layer 1300 can be formed by a dry etching method. The height of the pattern formed on the transparent material layer 1300 may be 10 nm or more and 10 占 퐉 or less. The pattern structure of the transparent material layer 1300 may be formed in an irregular arrangement in which patterns are regularly arranged or at least two pattern shapes are mixed.

5 to 7 show a case where the transparent material layer 1300 has a quadrangular pyramid shape, a quadrangular pyramid shape, or a straight shape. The p-electrode 1200 deposited on the transparent material layer 1300 by a three-dimensional shape of the transparent material layer 1300 has a quadrangular pyramid, a quadrangular pyramid, and a straight pattern. In addition to a quadrangular pyramid or quadrangular pyramid shape, a pattern can be formed in various polygonal pyramids or polygonal pyramid shapes, and the pattern shape may have a straight shape or a lattice shape. For example, when a material forming the transparent material layer has a specific crystallinity, a quadrangular pyramid or a trapezoidal pattern is formed. In the case of SiO ₂ , A hexagonal or hexagonal column may be formed as shown in FIG. 8 (a).

On the other hand, as shown in FIG. 8B, the pattern size of the transparent material layer 1300 may be reduced. By arranging small patterns of several nm to several tens nm, the emitted light can be reflected at a wide angle. FIG. 8 (c) shows a pattern in which the transparent material layer 1300 is patterned in a direction along the width direction of the light emitting diode. In addition, such a straight pattern can be formed in the other direction through two etching steps to form a lattice-like pattern (Fig. 8 (d)). In this case, patterns having different radiation angles may be formed by varying the height of the straight pattern formed in the width direction and the longitudinal direction of the light emitting diode.

  The pattern of the p-electrode 1200 can be adjusted according to how the pattern of the transparent material layer 1300 is formed, and the angle of reflection varies depending on the depth and interval of the pattern formed on the p-electrode 1200. By adjusting the pattern shape of the p-electrode 1200, the reflectance and the radiation angle of light can be controlled.

In this embodiment, the patterns are regularly arranged. However, as shown in FIG. 9, pattern structures of two or more patterns may be mixed and irregularly arranged. In this case, various types of patterns may be arranged with different sizes or intervals.

FIG. 10A and FIG. 10B are views showing a deposition form of a transparent material layer according to an embodiment of the present invention, and FIG. 11 is a cross-sectional view of a vertical light emitting diode according to another embodiment of the present invention, Type cladding layer.

The transparent material layer 1300 may be deposited on the entire upper surface of the p-type cladding layer 1400, or may be partially deposited to form a pattern. In an embodiment of the present invention, a transparent material layer 1300 is deposited on the entire upper surface of the p-type cladding layer 1400, as shown in FIG. 10 (a). After the transparent material layer 1300 is deposited on the entire upper surface of the p-type cladding layer 1400, only a part of the thickness of the transparent material layer 1300 is etched to form a pattern. The p-electrode 1200 is stacked with the p-type cladding layer 1400 and the transparent material layer 1300 interposed therebetween. At this time, the difference between the minimum thickness and the maximum thickness of the transparent material layer 1300 in the formed transparent material layer 1300, that is, the height of the formed pattern may be 10 nm or more and 10 m or less. This may vary depending on the material forming the transparent material layer 1300 or the desired radiation angle.

On the other hand, the transparent material layer 1300, which is additionally deposited between the p-type cladding layer 1400 and the p-electrode 1200 for patterning, is formed on the p-type cladding layer 1400 as shown in FIG. 10 (b) May be formed only on a part of the area. The transparent material layer 1300 is deposited on the entire area of the p-type cladding layer 1400 and then etched until a part of the p-type cladding layer 1400 is exposed, or the transparent material layer 1300 is p- After deposition on a part of the clad layer 1400, a pattern can be formed by etching.

11, after the transparent material layer 1300 is formed only on a partial area of the p-type cladding layer 1400, the p-electrode 1200 is entirely deposited thereon. In this case, the p-electrode 1200 partially contacts the p-type cladding layer 1400 directly. This method has an advantage that the material of the transparent material layer can be used as a patterning material both in the case of a conductor and in the case of a nonconductive material. In particular, nonconductive transparent materials, such as SiO ₂ , Si ₃ N ₄ , and Al ₂ O ₃ , which are often used as nonconductive materials, are easily etched because they are wet-etched and the patterning process is easy. Due to the difference in refractive index, It is possible to increase the reflectance of the entire p-electrode because it can reflect itself.

When the transparent material layer 1300 is partially deposited on the p-type cladding layer 1400, the thickness of the transparent material layer 1300, that is, the height of the formed pattern may be 10 nm or more and 10 m or less.

The vertical light emitting diode according to the present invention forms a pattern of p-electrodes by etching a transparent material layer. That is, various patterns can be formed without damaging the p-electrode by forming a pattern in a transparent material layer which is easy to etch in a desired shape and then forming a p-electrode in a transparent material layer in which a pattern is formed. Accordingly, the reflectance of light is increased and the emitting angle of the light emitting diode can be widened, and the radiation angle can be adjusted by adjusting the pattern as necessary. The vertical type light emitting diode according to the present invention is more effective in the light emitting diode because it can increase the reflectance of light emitted by using a patterned transparent material layer and realize a wide radiation angle.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of the present invention in order to facilitate description of the present invention and to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

1000: vertical type light emitting diode 1010: substrate
1020: buffer layer 1100: carrier
1200: p-electrode 1300: transparent material layer
1320: Photoresist 1340: Mask pattern
1400: p-type cladding layer 1500: active layer
1600: n-type cladding layer 1700: n-electrode

Claims (4)

A method of fabricating a nitride-based semiconductor light emitting diode having a pn junction structure,
forming a transparent material layer having a refractive index different from that of the p-type cladding layer and being a nonconductive transparent material on the p-type cladding layer so as to have a thickness of 10 nm or more and 10 m or less;
Forming a reflective metal electrode layer as a p-electrode on the p-type cladding layer on which the transparent material layer is partially deposited; And
And forming a reflective layer on the reflective metal electrode layer,
The pattern structure formed by the partially deposited layer of transparent material has a regular arrangement,
Wherein the reflective metal electrode layer has a three-dimensional pattern by a pattern formed by the transparent material layer,
Wherein the reflective metal electrode layer partially contacts the p-type cladding layer. The method according to claim 1,
Wherein the pattern structure formed by the transparent material layer is circular or polygonal. The method according to claim 1,
Wherein the pattern structure formed by the transparent material layer has a shape of a straight line or a lattice. A vertical type light emitting diode manufactured by the vertical type light emitting diode manufacturing method according to any one of claims 1 to 3.

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