KR101685092B1 - Edge light emitting diode and method for manufacturing the same - Google Patents

Abstract

The present invention relates to an edge light emitting diode and a method for manufacturing the same and, more specifically, to an edge light emitting diode and a method for manufacturing the same, for improving the efficiency of optical extraction in an edge direction. According to an embodiment of the present invention, the edge light emitting diode includes: a semiconductor stacking structure having an n-type semiconductor, an active layer, and a p-type semiconductor; a first reflective layer supplied on the lower side of the semiconductor stacking structure; a second reflective layer supplied on the upper side of the semiconductor stacking structure; and an optical extracting structure layer formed on one side of the semiconductor stacking structure. Light emitted from the active layer can be emitted laterally through the optical extracting structure layer.

Description

TECHNICAL FIELD [0001] The present invention relates to a side light emitting diode (LED)

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a side light emitting diode and a method of manufacturing the same. More particularly, the present invention relates to a side light emitting diode with improved light extraction efficiency in a lateral direction and a manufacturing method thereof.

A liquid crystal display (LCD) requiring a separate light source uses a plurality of fluorescent lamps such as a cold cathode fluorescent lamp (CCFL) and an external electrode fluorescent lamp (EEFL) as a light source Or a plurality of light emitting diodes (LEDs) are used. These light sources are provided in a backlight unit (BLU) such as a light guide plate, a plurality of optical sheets, and a reflection plate.

In particular, a semiconductor light emitting device such as a light emitting diode (LED) used as a light source by exchanging electricity by converting electricity into infrared rays or light using the characteristics of a compound semiconductor is widely used as a light source, a display device and a light source, It is possible to emit light of a desired wavelength with power and to suppress the emission of environmentally harmful substances such as mercury, and the development thereof is accelerating in consideration of energy saving and environmental protection aspects.

However, when a light emitting diode is used as a light source, light tends to concentrate and diverge into a narrow area. In order to apply this to a surface light source such as a display device, it is necessary to distribute the light evenly over a wide area.

The backlight unit (BLU) is roughly divided into an edge type and a direct type according to the position of the lamp relative to the display surface. Of these, the direct-type backlight unit is widely used in large-sized liquid crystal display devices because it has high light utilization rate, is easy to handle, and has no limitation on the size of the display surface.

A light emitting diode used in a direct-type backlight unit is divided into top emitting, bottom emitting or edge emitting according to the light emitting method. Due to the light efficiency of the light emitting diode, A bottom emission scheme is generally used. However, the light emitting diode backlight unit of the upper emission type or the lower emission type has a disadvantage that the light distribution and the light uniformity are lower than that of the side emission type.

A light emitting diode of a general side emitting type includes a lens for emitting light emitted from a light emitting diode chip in a lateral direction. Such a lens includes a funnel-shaped total internal reflection surface and a refracting surface which are symmetrical with respect to the central axis of the lens, And the refracting surface is formed in a serrated shape to refract light in a direction perpendicular to the central axis and emit.

The light emitting diode of the general side emission type is mounted inside the holes formed in the light guide plate, and the light emitted from the light emitting diode chip is emitted to the side of the lens and incident on the light guide plate. A light emitting diode of a general side emission type requires a lens having a very large height as compared with the height of the LED chip so that the thickness of the light emitting diode is determined by the thickness of the lens. Accordingly, there is a limit in reducing the thickness of the direct-type backlight unit (BLU) or the planar light source including the side-emitting type light emitting diode. These technical limitations are a fatal drawback to efforts to reduce the thickness of flat panel displays in recent years.

In addition, when light emitted from the light emitting diode chip is incident on the lens, a part of the light is reflected from the lower surface of the lens, and it is difficult to precisely process the total reflection surface and the refracting surface of the lens, There is a problem that the light extraction efficiency emitted from the light source is reduced.

Korean Patent Registration No. 10-1299528

In the present invention, the light emitted to the upper and lower sides is reflected to the side by using the reflection layer provided on the upper and lower parts of the semiconductor stacked structure, and the light extraction structure layer is formed on the side to effectively emit light, And a method of manufacturing the same.

According to an aspect of the present invention, there is provided a side-emitting diode including: a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer; A first reflective layer provided under the semiconductor stacked structure; A second reflective layer provided on the semiconductor stacked structure; And a light extracting structure layer formed on a side surface of the semiconductor stacked structure, and light emitted from the active layer may be emitted laterally through the light extracting structure layer.

And a passivation layer provided between a side surface of the semiconductor multilayer structure and the light extracting structure layer.

The light extracting structure layer may include nanorods grown in a direction crossing a side surface of the semiconductor multilayer structure.

The light extracting structure layer may further include a seed layer for growing the nanorods.

The light extracting structure layer may be formed of at least any one material selected from zinc oxide (ZnO), aluminum nitride (AlN), silicon dioxide (SiO _2), aluminum oxide (Al ₂ O _3), zirconium oxide (ZrO ₂₎ have.

According to another aspect of the present invention, there is provided a method of fabricating a side light emitting diode, comprising: forming a first reflective layer on one side of a substrate; Forming a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer on the other surface of the substrate opposite to the one surface of the substrate or on the first reflective layer; Forming a second reflective layer on the semiconductor stacked structure; And forming a light extracting structure layer on a side surface of the semiconductor stacked structure.

And forming a passivation layer on a side surface of the semiconductor stacked structure before the step of forming the light extracting structure layer.

Forming the light extracting structure layer includes: forming a seed layer on a side surface of the semiconductor stacked structure; And growing nanorods on the seed layer.

In the step of forming the seed layer, the seed layer may be formed by sputtering or electron beam evaporation.

In the step of forming the seed layer, the seed layer may be formed by obliquely depositing the substrate.

In the step of growing the nanorods, the nanorods may be grown by hydrothermal synthesis using a hydrothermal synthesis reactor.

And removing the seed layer formed on the second reflective layer or the lower portion of the first reflective layer.

Forming a sacrificial layer on the second reflective layer; And removing the sacrificial layer.

The side light emitting diode according to the present invention can improve the light extraction efficiency through the side surface of the light emitting diode by forming the light extracting structure layer on the side surface of the semiconductor stacked structure. Further, the light extracting structure layer can improve the intensity of light emitted horizontally from the side surface of the side light emitting diode, and accordingly, the surface light source including the side light emitting diode has many light incident perpendicularly to the incident surface of the light guide plate The reflectance is reduced and the light distribution characteristic can be improved.

Also, a passivation layer is provided between the semiconductor stacked structure and the light extracting structure layer to prevent a leakage current caused by the formation of the light extracting structure layer, thereby obtaining the same electrical characteristics as when the light extracting structure layer is not formed And a lateral light emitting diode having improved optical characteristics without deteriorating electrical characteristics through the formation of a light extracting structure layer can be manufactured.

Meanwhile, since the side light emitting diode of the present invention can emit light directly to the side of the light emitting diode by forming reflection layers on the upper and lower portions of the semiconductor stacked structure, it is necessary to use the lens which has been used in the conventional side emitting light emitting diode The thickness of the side light emitting diode can be remarkably reduced. Accordingly, the thickness of the planar light source including the side light emitting diode can be effectively reduced, and even if a plurality of light sources are disposed immediately below the light emitting surface, the planar light source is not directly emitted to the upper portion but emitted through the light guide plate. And it is possible to use a larger number of light emitting diodes than to arrange the light emitting diodes on the side surfaces, thereby providing a high luminance.

1 is a cross-sectional view illustrating a side light emitting diode according to an embodiment of the present invention;
2 is a view showing electrical and optical characteristics of each side of a side-light-emitting diode chip according to an embodiment of the present invention.
FIG. 3 is a graph showing electrical and optical characteristics of a side light emitting diode according to an embodiment of the present invention. FIG.
4 is a graph illustrating a leakage current blocking effect of the passivation layer according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating light emission characteristics of a side light emitting diode according to an embodiment of the present invention. FIG.
6 is a scanning electron microscope image of a light extracting structure layer of a side light emitting diode according to an embodiment of the present invention.
7 is a sectional view sequentially illustrating a method of manufacturing a side light emitting diode according to another embodiment of the present invention.
FIG. 8 is a cross-sectional view illustrating the oblique deposition according to another embodiment of the present invention. FIG.
9 is a cross-sectional view illustrating formation and removal of a sacrificial layer in a method of manufacturing a side light emitting diode according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. In the description, the same components are denoted by the same reference numerals, and the drawings are partially exaggerated in size to accurately describe the embodiments of the present invention, and the same reference numerals denote the same elements in the drawings.

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

1, a side light emitting diode according to an embodiment of the present invention includes a semiconductor stacked structure 130 including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer; A first reflective layer 120 provided under the semiconductor stacked structure 130; A second reflective layer 140 provided on the semiconductor stacked structure 130; And a light extracting structure layer 210 formed on a side surface of the semiconductor stacked structure 130. Light emitted from the active layer is incident on the light extracting structure layer 210 from the side of the semiconductor stacked structure 130, Lt; / RTI >

The semiconductor laminated structure 130 may include an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. The n-type semiconductor layer, the active layer, and the p-type semiconductor layer are formed of a compound semiconductor material doped with each conductive impurity For example, a gallium nitride compound semiconductor material having an InxAlyGa1-x-yN composition formula (where 0? X? 1, 0? Y? 1, 0? X + y? 1) These materials are not particularly limited.

The n-type semiconductor layer may be formed of a compound semiconductor layer doped with an n-type conductive impurity, and examples of the n-type conductive impurity include Si, Ge, and Sn. do. The active layer may be formed of a single quantum well layer or a multi-quantum well layer composed of a double heterostructure or an InGaN / GaN layer. The p-type semiconductor layer may be formed of a GaN layer or a GaN / AlGaN layer doped with a p-type conductivity type impurity. For example, Mg, Zn, Be or the like may be used as the p- , Mainly Mg is used. On the other hand, the semiconductor stacked structure 130 has various functions such as a GaN buffer layer, an n-type / p-type clad layer, and a p-type cap layer for improving lattice matching with a substrate formed of a material such as sapphire on the substrate 110 And may further include functional layers to perform. The n-type semiconductor layer and the p-type semiconductor layer are covered with an n-type electrode (or n-type pad electrode) 151 and a p-type electrode (or p Type pad electrode 152 may be formed to be in ohmic contact with each other. At this time, an interlayer insulating layer (not shown) may be provided between the semiconductor stacked structure 130 and the n-type pad electrode 151 or the p-type pad electrode 152.

The first reflective layer 120 may be provided below the semiconductor stack structure 130 and may be located below (or below) the substrate 110 or between the substrate 110 and the semiconductor stack structure 130 Light emitted from the active layer of the semiconductor stacked structure 130 is not emitted to the lower surface of the side light emitting diode and light incident on the lower surface is reflected to the inside to be emitted only from the side surface of the side light emitting diode. The first reflective layer 120 may include a metal reflective layer formed of a metal and a reflective Bragg reflection layer formed by alternately laminating oxide layers having different refractive indices (for example, SiO ₂ and TiO ₂ ) Reflecting: DBR) layer. The first reflective layer 120 formed in contact with the substrate 110 may include an SiO ₂ layer between the metal reflective layer and the substrate or may be formed to contact the SiO ₂ layer in the DBR layer And may be formed on any one of the upper surface and the lower surface of the substrate 110, but it may be located below the semiconductor stacked structure 130.

The second reflective layer 140 may be provided on the upper side of the semiconductor multilayer structure 130 to prevent light emitted from the active layer of the semiconductor multilayer structure 130 from being emitted to the upper surface of the side light emitting diode, So that the light can be emitted only from the side surface of the side light emitting diode. Also, the second reflective layer 140 may be formed of a metal Bragg reflector (DBR), which is formed of a metal and forms a mirror surface or alternately stacks oxide layers having different refractive indices (e.g., SiO ₂ and TiO ₂ ) Layer. Other layers may be provided between the semiconductor stacked structure 130 and the second reflective layer 140. The second reflective layer 140 may be located above the semiconductor stacked structure 130. [

FIG. 2 is a graph showing electrical and optical characteristics of each side of a side light-emitting diode chip according to an embodiment of the present invention.

Table 1 is a table showing electrical and optical characteristics of each side of the side light emitting diode chip according to an embodiment of the present invention.

side Electrical characteristic
(at 20mA) Optical properties
(at 100 mA) The first side 4.00 V 3.07 ㎽ / ㏛ Second side 4.09 V 2.90 ㎽ / ㏛ Third Side 4.06 V 3.03 ㎽ / ㏛ 4th face 4.00 V 3.02 ㎽ / ㏛

Referring to FIG. 2 and Table 1, it can be seen that the electrical and optical characteristics are substantially the same on each side of the side-surface light-emitting diode chip 100. The error between the maximum value and the minimum value is 0.09 V (at 20 mA, Electrical characteristics) and 0.17 ㎽ / ㏛ (at 100 mA, optical characteristics), showing similar electrical and optical characteristics in each side of the side light emitting diode chip 100.

Therefore, the side light emitting diode chip 100 used in the side light emitting diode of the present invention exhibits similar electrical and optical characteristics on each side, thereby increasing the light uniformity of the side light emitting diode. In particular, it may be more effective when the side light emitting diode is used for a planar light source.

However, only the side light emitting diode chip 100 has a low light output to the side of the side light emitting diode. Therefore, a method for improving the light extraction efficiency emitted from the side surface of the side light emitting diode needs to be devised.

The light extracting structure layer 210 may be formed on the side surface of the semiconductor stacked structure 130. The light extracting structure layer 210 may be formed on a side surface of the side light emitting diode chip 100 from which the light emitted from the active layer is emitted. The first and second reflective layers 120 and 140 may be formed on the semiconductor stacked structure 130 The semiconductor light emitting diode chip 100 may be formed only on the side surface of the semiconductor laminated structure 130 or on the entire side surface of the side light emitting diode chip 100.

In the side light emitting diode of the present invention, light emitted from the active layer may be emitted to the side of the side light emitting diode (or the side light emitting diode chip) through the light extracting structure layer 210. In the side surface of the semiconductor stacked structure 130 And may be emitted through the light extracting structure layer 210. The light extracting structure layer 210 can facilitate light escape from the inside of the semiconductor stacked structure 130, thereby achieving high light extraction efficiency.

The light extracting structure layer 210 may be formed as a single layer or a multi-layer structure composed of a material that is optically transparent and can easily form a surface texture structure such as a cylindrical shape, a conical shape, or a shape including both a cylindrical shape and a conical shape . The light extracting structure layer 210 is zinc oxide (ZnO), aluminum nitride (AlN), silicon dioxide (SiO _2), aluminum oxide (Al ₂ O _3), at least any one material selected from the group consisting of zirconium oxide (ZrO ₂₎ ≪ / RTI > The material such as zinc oxide (ZnO) has a characteristic of growing monocrystalline crystals, so that crystals can be grown in a certain direction, and accordingly light can be induced in a desired direction and light can be escaped, thereby improving light extraction efficiency.

The light extracting structure layer 210 may include nanorods 212 grown in a direction intersecting the side surfaces of the semiconductor stacked structure 130. The nano rod 212 can be disposed according to the direction in which the light is extracted, and can act as a waveguide of light. Thus, leakage of light to the side of the nanorod 212 (that is, to the upper or lower side) is prevented, thereby minimizing the loss of light, thereby improving the light extraction efficiency.

In addition, the light extracting structure layer 210 may further include a seed layer 211 for growing the nanorods 212. The seed layer 211 may allow the nanorods 212 to grow in a directional manner and the nanorods 212 may be deposited through the seeds to prevent growth of the nanorods 212 It may be possible to grow. For example, zinc oxide (ZnO) is silicon dioxide (SiO _2), titanium dioxide (TiO _2), does not grow such as aluminum oxide (Al ₂ O _3), silicon dioxide (SiO _2), titanium dioxide (TiO ₂₎ , Zinc oxide (ZnO) nanodots can be grown through zinc oxide (ZnO) seeds by depositing seeds of zinc oxide (ZnO) on the surfaces of aluminum oxide (Al ₂ O ₃ )

The direction in which the nanorods 212 are grown is based on the orientation of the particles constituting the seed layer 211. The direction of the growth of the nanorods 212 is changed by changing the orientation, Direction can be adjusted.

The nanorods 212 may be formed parallel to the bottom surface of the side light emitting diode chip 100 (e.g., perpendicular to the side surface of the side light emitting diode chip when the side surface of the side light emitting diode chip is vertical). In this case, the light emitted from the active layer can be output horizontally along the nanorods 212, so that the side light emitting diode of the present invention can enhance the intensity of light emitted horizontally from the side. In addition, since the surface light source including the side light emitting diode of the present invention increases the amount of light vertically incident on the incident surface of the light guide plate, the reflectance is reduced and the light distribution characteristic can be improved.

In addition, the nanorods 212 have nano-sized diameters, and the smaller the diameters, the higher the light extraction efficiency. That is, as the nanorods 212 are densely formed, the probability of light escape can be increased. Meanwhile, the nanorods 212 are preferably formed of a single crystal, but some of the crystallinity may be damaged due to other factors occurring during the growth of the crystal. However, since the dominant factor of the formation and growth of the nanorods 212 is the single crystal growth of materials such as zinc oxide (ZnO), there is no significant change in the light extraction efficiency depending on the length of the nanorods 212, Even if the crystallinity of the rod 212 is partially damaged, it does not become a big problem.

The seed layer 211 may be formed to be thin, and may be formed to a thickness of 5 to 100 nm. When the seed layer 211 is thinner than 5 nm, the nucleus, which is a site where the nanorods 212 are grown, is not sufficiently provided, and the growth of the nanorods 212 is not performed well. Nm, the deposition time of the seed layer 211 is not only long, but also becomes a thin film (or a material layer) through which light must pass, and can act as an obstacle to the escape of light. Accordingly, when the seed layer 211 has a thickness of 5 to 100 nm, the growth of the nanorods 212 can be performed well. Here, the deposition rate of the seed layer 211 may be 0.2 to 0.3 Å / s.

FIG. 3 is a graph showing electrical and optical characteristics of a side light emitting diode according to an embodiment of the present invention. FIG. 3 (a) is a graph showing electrical characteristics and FIG. 3 (b) is a graph showing optical characteristics.

3 (a) shows the electrical characteristics of the side light emitting diode according to the present invention. When the light extracting structure layer 210 made of zinc oxide (ZnO) is formed on the side surface of the semiconductor stacked structure 130, Is the same as that in the case where the light extracting structure layer 210 is not formed. Therefore, even when the light extracting structure layer 210 made of zinc oxide (ZnO) or the like is formed on the side surface of the semiconductor multilayer structure 130, the side light emitting diode according to the present invention shows no change in electrical characteristics have. This means that when the same current is applied, the voltage is not lowered than when the light extracting structure layer 210 is not formed, and the use efficiency of the input current is equal to that when the light extracting structure layer 210 is not formed .

3 (b) shows the optical characteristics of the side light emitting diode according to the present invention. When the light extracting structure layer 210 such as zinc oxide (ZnO) is formed on the side surface of the semiconductor stacked structure 130, it can be seen that the optical characteristic is improved about twice as compared with the case where the light extracting structure layer 210 is not formed when the same power source is applied as shown in the graph of FIG. From this, it can be seen that the light extraction efficiency (or the output value) through the side surface of the side light emitting diode can be improved by the light extracting structure layer 210 under the same power source (or input value).

The side light emitting diode according to the present invention may further include a passivation layer 160 provided between the side surface of the semiconductor stacked structure 130 and the light extracting structure layer 210. Although the optical characteristics of the side light emitting diode can be improved by forming the light extracting structure layer 210 directly on the side surface of the semiconductor stacked structure 130 to be in contact with the semiconductor stacked structure 130, Leakage current is generated between the side surface of the light extracting structure layer 210 and the side surface of the light extracting structure layer 210, thereby deteriorating the electrical characteristics of the side light emitting diode. The passivation layer 160 may prevent such a leakage current from being deteriorated in electrical characteristics of the side light emitting diode.

For example, when the light extracting structure layer 210 is made of zinc oxide (ZnO), zinc oxide (ZnO) has an n-type semiconductor property and a leakage current is generated. The passivation layer 160 is formed of zinc oxide ZnO) can be isolated and leakage current can be prevented.

The light extracting structure layer 210 may be formed of a nanorod 211 even if the light extracting structure layer 210 is made of an insulating material such as silicon dioxide (SiO ₂ ) or aluminum oxide (Al ₂ O ₃ ) The passivation layer 160 is formed to compensate for the insufficient insulating property of the light extracting structure layer 210 to completely block the leakage current because the insulating layer 210 has a small thickness, .

The passivation layer 160 may be formed of an insulating material such as silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), hafnium monoxide (HfO 2), or the like and may be formed by atomic layer deposition However, these materials and deposition methods are not particularly limited.

FIG. 4 is a graph showing a leakage current blocking effect of the passivation layer according to an embodiment of the present invention. FIG. 4 is a graph of a current / voltage according to presence or absence of a passivation layer in a side light emitting diode having a light extracting structure layer. If a current of 10 ^-4 mA or less is measured when a voltage of -5 V is applied, it can be judged that there is no leakage current. If a current higher than 10 ^-4 mA is measured, it can be judged that a leakage current exists have.

4, it can be seen that the leakage current is lowered through the passivation layer 160 and the leakage current due to the light extracting structure layer 210 such as zinc oxide (ZnO) is blocked by the passivation layer 160 . When the light extracting structure layer 210 is formed on the side surface of the semiconductor stacked structure 130, the leakage current is increased like a graph in which the passivation layer 160 of FIG. 4 is not formed (i.e., a black line graph). However, in the present invention, a passivation layer 160 is provided between the side surface of the semiconductor stacked structure 130 and the light extracting structure layer 210 to form a graph (i.e., a red line graph) in which the passivation layer 160 of FIG. The leakage current can be lowered.

Therefore, the side light emitting diode of the present invention may be provided with a passivation layer 160 between the side surface of the semiconductor stacked structure 130 and the light extracting structure layer 210, and the passivation layer 160 may be provided between the semiconductor stacked structure 130 The leakage current due to the light extracting structure layer 210 such as zinc oxide (ZnO) can be blocked or suppressed between the side surface of the light extracting structure layer 210 and the light extracting structure layer 210.

In the meantime, the side light emitting diode of the present invention may be formed such that the passivation layer 160 extends from the side surface of the semiconductor stacked structure 130 to cover all exposed surfaces of the side light emitting diode. In this case, since the passivation layer 160 is only deposited vertically on the second reflective layer 140, a passivation layer (not shown) is formed between the side surface of the semiconductor stacked structure 130 and the light extracting structure layer 210 160 may be provided. In addition, it is also possible to prevent electrical defects at the upper part of the side-surface light-emitting diode chip 100, which is effective to maintain the electrical characteristics of the side-surface light-emitting diode. In forming the seed layer 211, It may serve as a cover for blocking the seed layer 211 formed on the upper part.

Accordingly, the side light emitting diode according to the present invention can improve the optical characteristics of the side light emitting diode through the light extracting structure layer 210 while maintaining excellent electrical characteristics by the passivation layer 160.

FIG. 5 is a graph illustrating light emission characteristics of a side light emitting diode according to an exemplary embodiment of the present invention. FIG. 5 (a) is a graph showing the intensity of light emitted by a position, and FIG. 5 (b) is an optical microscope image.

Referring to FIG. 5, when the light extracting structure layer 210 is not formed, it can be seen that light is locally emitted from the side surface of the side light emitting diode, and the light emitting property of the side light emitting diode is degraded. On the other hand, it can be seen that the side light emitting diode according to the present invention extracts light evenly in the entire area of the side surface, and it can be confirmed that the luminescence intensity is high in the entire area of the side surface. It can be seen that the luminescence intensity of the side light emitting diode according to the present invention is excellent because the luminescence intensity of the side light emitting diode according to the present invention is superior to the luminescence intensity of the side light emitting diode according to the present invention. have.

This can be confirmed not only in FIG. 5 (a) but also in an optical microscope (OM) image of FIG. 5 (b).

6 is a scanning electron microscope image showing a light extracting structure layer of a side light emitting diode according to an embodiment of the present invention.

Referring to FIG. 6, it can be seen that the nanorods 212 such as zinc oxide (ZnO) are uniformly grown on the side of the side light emitting diode according to the present invention through a scanning electron microscope (SEM) have. For example, when the side surface of the side light emitting diode is vertical, the nanorods 212 such as zinc oxide (ZnO) may grow perpendicular to the side surface of the side light emitting diode as shown in FIG. 6, Can be formed tightly. Thus, the light extraction efficiency is increased through the light extracting structure layer 210 and the light extraction efficiency is improved, so that the optical characteristics and light emitting characteristics of the side light emitting diode can be improved.

7 is a sectional view sequentially illustrating a method of manufacturing a side light emitting diode according to another embodiment of the present invention.

Referring to FIG. 7, a method of manufacturing a side light emitting diode according to another embodiment of the present invention will be described in detail.

According to another aspect of the present invention, there is provided a method of manufacturing a side light emitting diode, comprising: forming a first reflective layer on one side of a substrate (S100); Forming (S200) a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer on the other surface of the substrate opposite to the one surface of the substrate or on the first reflective layer; Forming a second reflective layer on the semiconductor stacked structure (S300); And forming a light extracting structure layer on the side surface of the semiconductor stacked structure (S600).

The above steps are not limited to the above procedure, and may be changed as necessary. In the manufacturing of the side light emitting diode, the above steps may be included. The above procedures represent one embodiment, which will be described below with reference to an embodiment.

First, a first reflective layer 120 is formed on one surface of a substrate 110 as shown in FIG. 7A (S100). The first reflective layer 120 may be formed on one surface of the substrate 110 and may be formed on either the upper surface or the lower surface of the substrate 120. The first reflective layer 120 reflects light incident to the substrate 110 from the light emitted from the active layer of the semiconductor multilayer structure 130 to emit light only from the side of the side light emitting diode.

Next, as shown in FIG. 7 (b), a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer is formed on the other surface of the substrate 110 opposite to one surface of the substrate 110 or on the first reflective layer 120 The structure 130 is formed (S200). The semiconductor multilayer structure 130 may be formed on the other surface of the substrate 110 or on the first reflective layer 120. The first reflective layer 120 may be positioned below the semiconductor multilayer structure 130, The semiconductor laminated structure 130 may be formed on a surface of the substrate 110 which faces the surface on which the first reflective layer 120 is formed, as shown in FIG. The semiconductor stacked structure 130 may be formed by stacking an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and light is emitted from the active layer.

Next, a second reflective layer 140 is formed on the semiconductor stacked structure 130 as shown in FIG. 7C (S300). The second reflective layer 140 reflects light emitted in the direction opposite to the substrate 110 among the light emitted from the active layer of the semiconductor stacked structure 130 to the inside so that light can be emitted only from the side of the side light emitting diode.

Accordingly, the first reflective layer 120 and the second reflective layer 140 are formed so that light emitted from the active layer of the semiconductor stacked structure 130 is not emitted to the upper surface or the lower surface, can do. Accordingly, since the lens which is essentially used in the light emitting diode of the conventional side emission type is not required, the thickness of the side light emitting diode can be remarkably reduced.

(S410) forming an n-type pad electrode 151 to be electrically connected to the n-type semiconductor layer by patterning the second reflective layer 140, the p-type semiconductor layer, and the active layer, as shown in FIG. And forming the p-type pad electrode 152 to be electrically connected to the p-type semiconductor layer by patterning the second reflective layer 140 (S420). The order of forming the n-type pad electrode 151 and the p-type pad electrode 152 is not limited to this. On the other hand, an interlayer insulating layer (not shown) may be formed before the n-type pad electrode 151 and the p-type pad electrode 152 are formed. An interlayer insulating layer (not shown) is provided between the second reflective layer 140 and the n-type pad electrode 151 and / or the second reflective layer 140 and the p-type pad electrode 152 to form a second reflective layer 140, Type pad electrode 151 and the n-type pad electrode 151 and / or the p-type pad electrode 152 can be insulated from each other. In the case of the n-type pad electrode 151, So that the semiconductor stacked structure 130 and the n-type pad electrode 151 can be insulated from each other.

The method may further include forming a passivation layer 160 on the side surface of the semiconductor stacked structure 130 (S500) before forming the light extracting structure layer (S600) as shown in FIG. 7 (e). Although the optical characteristics of the side light emitting diode can be improved by forming the light extracting structure layer 210 directly on the side surface of the semiconductor stacked structure 130 to be in contact with the semiconductor stacked structure 130, Leakage current is generated between the side surface of the light extracting structure layer 210 and the side surface of the light extracting structure layer 210, thereby deteriorating the electrical characteristics of the side light emitting diode. The passivation layer 160 may prevent such a leakage current from being deteriorated in electrical characteristics of the side light emitting diode. The passivation layer 160 may be formed of an insulating material such as silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), hafnium monoxide (HfO 2), or the like and may be formed by atomic layer deposition However, these materials and deposition methods are not particularly limited.

On the other hand, when the n-type and p-type pad electrodes 150 are formed of a material such as gold (Au) in which the material of the light extracting structure layer 210 such as zinc oxide (ZnO) Type pad electrode 150 may extend from the side surface of the semiconductor stacked structure 130 to cover the n-type and p-type pad electrodes 150. [ In this case, since the passivation layer 160 is only deposited vertically on the second reflective layer 140, a passivation layer (not shown) is formed between the side surface of the semiconductor stacked structure 130 and the light extracting structure layer 210 160 may be provided. In addition, it is possible to prevent electrical defects at the upper part of the side-surface light-emitting diode chip 100, thereby being effective in maintaining the electrical characteristics of the side-surface light-emitting diode. When the nanorods 212 are grown, It is possible to prevent the formation of nanorods 212 such as zinc oxide (ZnO) on the substrate 150.

Accordingly, the passivation layer 160 can improve the optical characteristics of the side light emitting diode through the light extracting structure layer 210 while maintaining excellent electrical characteristics.

Then, the light extracting structure layer 210 is formed on the side surface of the semiconductor stacked structure 130 (S600). The light extracting structure layer 210 may be formed on a side surface of the side light emitting diode chip 100 in which the light emitted from the active layer is emitted. The first and second reflective layers 120 and 140 may be formed on the semiconductor stacked structure 130 The semiconductor light emitting diode chip 100 may be formed only on the side surface of the semiconductor laminated structure 130 or on the entire side surface of the side light emitting diode chip 100. The light extracting structure layer 210 can facilitate light escape from the inside of the semiconductor stacked structure 130, thereby achieving high light extraction efficiency. Further, the light extracting structure layer 210 may be a single layer or a multi-layer structure composed of a material capable of easily forming a surface texture structure such as a cylindrical shape, a conical shape, a shape including both a cylindrical shape and a conical shape, . The light extracting structure layer 210 is zinc oxide (ZnO), aluminum nitride (AlN), silicon dioxide (SiO _2), aluminum oxide (Al ₂ O _3), at least any one material selected from the group consisting of zirconium oxide (ZrO ₂₎ ≪ / RTI > The material such as zinc oxide (ZnO) has a characteristic of growing monocrystalline crystals, so that crystals can be grown in a certain direction, and accordingly light can be induced in a desired direction and light can be escaped, thereby improving light extraction efficiency.

The step S600 of forming the light extracting structure layer may include forming a seed layer 211 on the side surface of the semiconductor stacked structure 130 (S610); And growing the nanorods 212 on the seed layer 211 (S620).

A seed layer 211 is formed on the side surface of the semiconductor stacked structure 130 as shown in FIG. 7 (f) (S610). The seed layer 211 may allow the nanorods 212 to grow in a directional manner and the nanorods 212 may be deposited through the seeds to prevent growth of the nanorods 212 It may be possible to grow. For example, zinc oxide (ZnO) is silicon dioxide (SiO _2), titanium dioxide (TiO _2), does not grow such as aluminum oxide (Al ₂ O _3), silicon dioxide (SiO _2), titanium dioxide (TiO ₂₎ , Zinc oxide (ZnO) nanodots can be grown through zinc oxide (ZnO) seeds by depositing seeds of zinc oxide (ZnO) on the surfaces of aluminum oxide (Al ₂ O ₃ ) Even if the passivation layer 160 is made of a material such as silicon dioxide (SiO ₂ ) or aluminum oxide (Al ₂ O ₃ ) in which zinc oxide (ZnO) nanorods are not grown, the passivation layer 160 is oxidized Zinc (ZnO) nanorods can be grown. Thus, the seed layer 211 may allow the nanorods 212 to grow regardless of the material from which the light extracting structure layer 210 is formed.

The direction in which the nanorods 212 are grown is based on the orientation of the particles constituting the seed layer 211. The direction of the growth of the nanorods 212 is changed by changing the orientation, Direction can be adjusted.

The seed layer 211 may be formed by sputtering or E-beam evaporation in the step of forming the seed layer S610. When the seed layer 211 is formed by the hydrothermal method, a material in which the nanorods 212 are not grown (for example, in the case of ZnO nanorods, SiO ₂ , TiO ₂ , Al ₂ O ₃ The seed layer 211 can not be formed. However, if the seed layer 211 is formed by sputtering or electron beam deposition, the seed layer 211 can be formed by depositing a seed on a material on which the nanorods 212 are not grown.

The seed layer 211 should be thin to a thickness of 5 to 100 nm. If the seed layer 211 is formed by sputtering or electron beam evaporation, the seed layer 211 may be formed thin. On the other hand, when the seed layer 211 is thinner than 5 nm, the growth of the nanorods 212 is not performed well. When the seed layer 211 becomes thicker than 100 nm, the seed layer 211 is formed by sputtering or electron beam evaporation The deposition time of the seed layer 211 is not only long, but also becomes another thin film (or a material layer) through which light must pass and can act as an obstacle to the escape of light. Accordingly, in the present invention, the seed layer 211 may be thinned to a thickness of 5 to 100 nm through sputtering or electron beam evaporation, so that the growth of the nanorods 212 can be performed well. Here, the deposition rate of the seed layer 211 may be 0.2 to 0.3 Å / s.

FIG. 8 is a cross-sectional view illustrating the oblique deposition of the side light emitting diode according to another embodiment of the present invention. FIG. 8 (a) is a side light emitting diode chip loaded, FIG. 8 (c) is a view illustrating deposition of a seed on the side surface of the side light-emitting diode chip.

In the step of forming the seed layer S610, the seed layer 211 may be formed by oblique evaporation by tilting the substrate 110 to form the seed layer 211 on the side surface of the side light-emitting diode chip 100 . The oblique angle deposition (OAD) method differs from the general deposition method in which the substrate 110 and the evaporation source 320 are horizontally positioned so that the substrate 110 is inclined at a constant angle with respect to the evaporation source 320 Means a method of depositing. That is, when the supporting substrate 10 is tilted and the side-emitting light emitting diode chip 100 is loaded on the supporting substrate 10, the supporting substrate 10 is inclined by using the substrate supporting part 11 capable of adjusting the inclination of the supporting substrate 10 The seed layer 211 may be formed by tilting the side light emitting diode chip 100 including the substrate 110 and depositing the seed on the side surface of the side light emitting diode chip 100. The seed layer 211 may be formed on each side of the side light emitting diode chip 100 by adjusting the tilting direction of the side light emitting diode chip 100. The substrate supporting portion 11 may be formed on the supporting substrate 10 may be tilted at an angle of -80 to 80 °, and the deposition apparatus 300 may include the support 310 and the evaporation source 320. In this case, the seed layer 211 can be formed only on the side surface of the side light-emitting diode chip 100, and the seed layer 211 formed on the side surface of the side light-emitting diode chip 100 can be removed, Time can be reduced. And the thickness of each side of the side light-emitting diode chip 100 can be adjusted. Thus, by forming the seed layer 211 having the same thickness on all sides, the light uniformity of the side light-emitting diode manufactured by the manufacturing method of the present invention can be increased have. Particularly, in the case of using the side light emitting diode chip 100 of the present invention showing similar electrical and optical characteristics in each side, the light uniformity of the side light emitting diode can be more effectively improved, It may be more effective when the light emitting diode is used for a planar light source.

In order to form the seed layer 211 on the side surface of the side light emitting diode chip 100, the side surface of the side light emitting diode chip 100 is inclined so that the seed is deposited on the side surface of the side light emitting diode chip 100 . In this case, it is easier to form the seed layer 211 than in the case where the side surface of the side surface light emitting diode chip 100 is vertical, and total reflection on the side surface of the side surface light emitting diode chip 100 can be reduced, . In addition, even when the side surface of the side light emitting diode chip 100 is inclined, the nanorods 212 can be grown in parallel with the bottom surface of the side light emitting diode chip 100. At this time, the length of the nanorods 212 is adjusted so that the side surface of the side light emitting diode chip 100 is inclined, but the side surface of the side light emitting diode may be a vertical surface (or a plane surface).

And removing the seed layer 211 formed on the second reflective layer 140 or the lower portion of the first reflective layer 120. The seed layer 211 may be deposited on the side surface of the side light emitting diode chip 100 by depositing by a general deposition method but the seed layer 211 may be deposited on the side opposite to the deposition source 320, The seed layer 210 is formed on the upper surface of the second reflective layer 140 or on the lower surface of the first reflective layer 120 (i.e., the surface opposite to the evaporation source) in order to prevent the growth of the nanorods 212. [ (211) should be removed. The upper portion of the second reflective layer 140 and the lower portion of the first reflective layer 120 (that is, the upper and lower surfaces of the LED chip) are connected to a package substrate (not shown) If the seed layer 211 is formed, electrical characteristics may be deteriorated or an electrical defect may occur, and bonding with the package substrate (not shown) may be a problem. Further, it may be a problem when patterning the passivation layer 160 or the like for electrical connection at the time of packaging.

For example, after the passivation layer 160 is formed, the seed layer 211 may be formed by flipping the substrate 110 (i.e., the side light emitting diode chip). In this case, the seed layer 211 is formed on the first reflective layer 120 that is not electrically connected, so that there is no problem in electrical characteristics. Also, when the seed layer 211 formed on the first reflective layer 120 is removed for stable bonding with the package substrate (not shown), the seed layer 211 is easily removed by a simple removal method such as hydrochloric acid treatment or the like can do. At this time, the nanorods 212 may be grown after the packaging. The nanorods 212 are generally not grown except for the seed layer 211 so that there is no problem in growing the nanorods 212 after packaging and the nanorods 212 are grown on the bonding wires There is no problem even in the case where the bonding wire (not shown) or the like can be grown without the seed and the nanorods 212 can grow. On the other hand, packaging after the growth of the nanorods 212 makes it difficult to open the n-type and p-type pad electrodes 150 for electrical connection.

FIG. 9 is a cross-sectional view illustrating formation and removal of a sacrificial layer in a method of fabricating a side light emitting diode according to another embodiment of the present invention. FIG. 9A is a diagram illustrating a side light emitting diode chip loaded, 9 (c) is a view of depositing seeds on top of the side light-emitting diode chips, and FIG. 9 (d) is a view showing a state in which a seed is deposited on the surface of the side light-emitting diode chip and the sacrifice layer And FIG. 9 (e) is a drawing where the sacrificial layer is removed.

Referring to FIG. 9, a sacrificial layer 220 is formed on a second reflective layer 140. And the sacrificial layer 220 may be removed. A method of removing the seed layer 211 formed on the upper part of the second reflective layer 140 or the lower part of the first reflective layer 120 may include removing the seed layer 211 on the upper part of the second reflective layer 140 or on the lower part of the first reflective layer 120 The sacrificial layer 220 is removed together with the seed deposited on the sacrificial layer 220 after depositing the seed to form a seed layer 220 on the upper part of the second reflective layer 140 or on the lower part of the first reflective layer 120. [ The layer 211 may be removed. Accordingly, the seed layer 211 may be formed only on the side surface of the side light emitting diode chip 100 by a simple method of removing the sacrificial layer 220. The sacrificial layer 220 may be a photoresist (PR), a tape, a glass, or the like. When the sacrificial layer 220 is a photoresist (PR), a sacrificial layer If the sacrificial layer 220 is a tape, the sacrificial layer 220 can be removed by a simple method of removing the tape on which the seed has been deposited. In the case where the sacrificial layer 220 is a glass, The glass serves as a cover so as to prevent the seed from being deposited on the upper portion of the second reflective layer 140 or the lower portion of the first reflective layer 120 and then to remove the glass by a simple method.

In order to prevent the seed layer 211 from being deposited on the second reflective layer 140 or the first reflective layer 120 even when the seed layer 211 is formed by the oblique deposition (OAD) method, ) Method, the seed layer 211 can be formed after the sacrifice layer 220 is formed. In this case, the seed layer 211 can be formed more effectively on the side surface of the side light emitting diode chip 100.

Next, the nanorods 212 are grown on the seed layer 211 as shown in FIG. 7 (g) (S620). The nano rod 212 can be disposed according to the direction in which the light is extracted, and can act as a waveguide of light. Thus, leakage of light to the side of the nanorod 212 (that is, to the upper or lower side) is prevented, thereby minimizing the loss of light, thereby improving the light extraction efficiency.

In the step of growing the nanorods (S620), the nanorods 212 may be grown by hydrothermal synthesis using a hydrothermal synthesis reactor. The hydrothermal synthesis method is a method of synthesizing or growing crystals by using properties depending on the solubility, temperature, pressure and solvent concentration of a metal salt, oxide, hydrate or metal powder in a solution state or a suspension state. As a liquid phase synthesis method, a method of synthesizing a substance using water or an aqueous solution at a high temperature and a high pressure may be used. In the hydrothermal synthesis, a mineralizer may be added to increase the solubility of the solution. The rate of nucleation transition can vary greatly. The mineralizer is not only important for lowering the synthesis temperature during hydrothermal synthesis, but also for selective synthesis of the desired compound, so selection of mineralizer is very important for hydrothermal synthesis.

For example, the hydrothermal synthesis method of zinc oxide (ZnO) nanorods will first produce an aqueous solution in which zinc oxide (ZnO) nanorods can be synthesized. An aqueous solution prepared by dissolving zinc nitrate hexahydrate (Zn (NO ₃ ) ₂ · 6H ₂ O) and hexamethylenetetramine ((CH ₂ ) ₆ N ₄ ) in a desired ratio was mixed with zinc oxide (ZnO) Zinc oxide (ZnO) nanorods are synthesized in an aqueous solution while maintaining the growth temperature and pressure for a suitable period of time. At this time, zinc oxide (ZnO) nanorods are grown on the zinc oxide (ZnO) seed when a sample in which zinc oxide (ZnO) seeds are deposited is present in the aqueous solution.

These zinc oxide (ZnO) nanorods can change the growth pattern depending on the concentration, pressure, temperature and growth time of the aqueous solution. Growth conditions of zinc oxide (ZnO) nanorods grown to improve the light extraction efficiency of the lateral light emitting diode are Zn ₂ N 6 hexahydrate (Zn (NO ₃ ) ₂ .6H ₂ O) and hexamethylenetetramine (C ₆ H ₁₂ N ₄ ) can be mixed in a ratio of 1: 1, and a 10 to 120 mmol aqueous solution can be used. The growth temperature, the growth pressure and the growth time can be adjusted as needed. C, and the growth pressure can be adjusted within 30 kg / cm < 2 >.

Therefore, by growing the nanorods 212 by the hydrothermal synthesis method, the nanorods 212 can be grown simply and quickly. In addition, the growth mode of the nanorods 212 can be easily changed by adjusting the concentration, pressure, temperature, and growth time of the aqueous solution.

The nanorods 212 may be grown using a hydrothermal synthesis reactor (not shown). The hydrothermal synthesis reactor can perform hydrothermal synthesis for various materials, and since most of the powders are synthesized under the conditions of 300 ° C and 85 kg / cm 2, precise processes for temperature rise and pressure retention can be performed. Accordingly, the nanorods 212 can be uniformly grown on the side surface of the side light-emitting diode chip 100.

The nanorods 212 may be formed parallel to the bottom surface of the side light emitting diode chip 100 (e.g., perpendicular to the side surface of the side light emitting diode chip when the side surface of the side light emitting diode chip is vertical). In this case, the light emitted from the active layer can be output horizontally along the nanorods 212, so that the side light emitting diode of the present invention can enhance the intensity of light emitted horizontally from the side. In addition, since the surface light source including the side light emitting diode of the present invention increases the amount of light vertically incident on the incident surface of the light guide plate, the reflectance is reduced and the light distribution characteristic can be improved.

In addition, the nanorods 212 have nano-sized diameters, and the smaller the diameters, the higher the light extraction efficiency. That is, as the nanorods 212 are densely formed, the probability of light escape can be increased. Meanwhile, the nanorods 212 are preferably formed of a single crystal, but some of the crystallinity may be damaged due to other factors occurring during the growth of the crystal. However, since the dominant factor of the formation and growth of the nanorods 212 is the single crystal growth of materials such as zinc oxide (ZnO), there is no significant change in the light extraction efficiency depending on the length of the nanorods 212, Even if the crystallinity of the rod 212 is partially damaged, it does not become a big problem.

Accordingly, in the present invention, the nanorods 212 can be grown in parallel with the bottom surface of the side light-emitting diode chip 100 by growing the nanorods 212 by a hydrothermal synthesis method using a hydrothermal synthesis reactor (not shown) So that the nanorods 212 can be closely formed, and a precise process can be performed.

In addition, in the present invention, the light extracting efficiency to the side can be improved by forming the concavo-convex structure on at least one side of the both surfaces of the substrate to effectively extract the light emitted from the semiconductor stacked structure through the side surface of the light emitting diode, It is possible to improve the optical characteristics of the surface light source including the side light emitting diode or the direct-type backlight unit (BLU).

As described above, in the present invention, the light extracting structure layer may be formed on the side surface of the semiconductor stacked structure to improve the light extraction efficiency through the side surface of the light emitting diode. Further, the light extracting structure layer can improve the intensity of light emitted horizontally from the side surface of the side light emitting diode, and accordingly, the surface light source including the side light emitting diode has many light incident perpendicularly to the incident surface of the light guide plate The reflectance is reduced and the light distribution characteristic can be improved. Also, a passivation layer is provided between the semiconductor stacked structure and the light extracting structure layer to prevent a leakage current caused by the formation of the light extracting structure layer, thereby obtaining the same electrical characteristics as when the light extracting structure layer is not formed And a lateral light emitting diode having improved optical characteristics without deteriorating electrical characteristics through the formation of a light extracting structure layer can be manufactured. Meanwhile, since the side light emitting diode of the present invention can emit light directly to the side of the light emitting diode by forming reflection layers on the upper and lower portions of the semiconductor stacked structure, it is necessary to use the lens which has been used in the conventional side emitting light emitting diode The thickness of the side light emitting diode can be remarkably reduced. Accordingly, the thickness of the planar light source including the side light emitting diode can be effectively reduced, and even if a plurality of light sources are disposed immediately below the light emitting surface, the planar light source is not directly emitted to the upper portion but emitted through the light guide plate. And it is possible to use a larger number of light emitting diodes than to arrange the light emitting diodes on the side surfaces, thereby providing a high luminance.

As used in the above description, the term " on " means a case that is not directly in contact with but directly opposed to the upper, lower or side, and is located opposite to the upper, lower or entire side It is also possible to position them partially opposed to each other, meaning that they are in direct contact with the upper, lower or side surfaces. Thus, the substrate may be the surface (upper surface, lower surface or side surface) of the substrate, or may be the surface of the material layer (or film) deposited on the surface of the substrate.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the embodiments set forth herein. Those skilled in the art will appreciate that various modifications and equivalent embodiments may be possible. Accordingly, the technical scope of the present invention should be defined by the following claims.

10: Support substrate 11:
100: side light emitting diode chip 110: substrate
120: first reflecting layer 130: semiconductor laminated structure
140: second reflective layer 150: n-type and p-type pad electrodes
151: n-type pad electrode 152: p-type pad electrode
160: passivation layer 210: light extracting structure layer
211: seed layer 212: nanorod
300: Deposition apparatus 310: Support
320: evaporation source

Claims (13)

a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer;
A first reflective layer provided under the semiconductor stacked structure;
A second reflective layer provided on the semiconductor stacked structure; And
And a light extracting structure layer formed on a side surface of the semiconductor laminated structure,
Light emitted from the active layer is emitted laterally through the light extracting structure layer,
Wherein the light extracting structure layer includes nanorods grown in a direction crossing a side surface of the semiconductor multilayer structure.
The method according to claim 1,
Further comprising a passivation layer provided between a side surface of the semiconductor stacked structure and the light extracting structure layer.
delete The method according to claim 1,
Wherein the light extracting structure layer further comprises a seed layer for growing the nanorods.
The method according to claim 1,
The light extracting structure layer side consisting of at least any one material selected from zinc oxide (ZnO), aluminum nitride (AlN), silicon dioxide (SiO _2), aluminum oxide (Al ₂ O _3), zirconium oxide (ZrO ₂₎ Light emitting diode.
Forming a first reflective layer on one side of the substrate;
Forming a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer on the other surface of the substrate opposite to the one surface of the substrate or on the first reflective layer;
Forming a second reflective layer on the semiconductor stacked structure; And
And forming a light extracting structure layer on a side surface of the semiconductor stacked structure,
Wherein forming the light extracting structure layer comprises:
And growing a nanorod on a side surface of the semiconductor multilayer structure in a direction crossing the side surface of the semiconductor multilayer structure.
The method of claim 6,
Further comprising forming a passivation layer on a side of the semiconductor stack structure prior to the step of forming the light extracting structure layer.
The method of claim 6,
The step of forming the light extracting structure layer may further include forming a seed layer on a side surface of the semiconductor multilayer structure before the step of growing the nanorods,
And growing the nanorods on the seed layer in the step of growing the nanorods.
The method of claim 8,
Wherein the seed layer is formed by sputtering or electron beam evaporation in the step of forming the seed layer.
The method of claim 9,
Wherein the seed layer is formed by oblique deposition by tilting the substrate in the step of forming the seed layer.
The method of claim 6,
Wherein the step of growing the nanorods comprises growing the nanorods by hydrothermal synthesis using a hydrothermal synthesis reactor.
The method of claim 8,
And removing the seed layer formed on the second reflective layer or the lower portion of the first reflective layer.
The method of claim 8,
Wherein forming the light extracting structure layer comprises:
Further comprising forming a sacrificial layer on the second reflective layer prior to forming the seed layer,
Further comprising removing the sacrificial layer after forming the seed layer. ≪ RTI ID = 0.0 > 11. < / RTI >

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