KR20150037215A - Light emitting device having wide beam angle and method of fabricating the same - Google Patents

Abstract

Provided are a light emitting device having a wide beam angle and a method of fabricating the same. The light emitting device includes: a light emitting structure, a transparent substrate located on the light emitting structure, and an anti-reflection layer which covers the light emitting structure and the side of the transparent substrate. At least part of the upper side of the transparent substrate is exposed. Accordingly, uniform light is emitted regardless of a light emitting angle. The beam angle of the light emitting device is wide.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light emitting device having a wide directivity angle,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device and a manufacturing method thereof, and more particularly, to a light emitting device having a wide directivity angle through a surface treatment or the like, and a manufacturing method thereof.

BACKGROUND ART [0002] Light emitting devices are inorganic semiconductor devices that emit light generated by recombination of electrons and holes, and have recently been used in various fields such as displays, automobile lamps, and general lighting. Particularly, nitride semiconductors such as gallium nitride and aluminum nitride have direct transition characteristics and can be manufactured to have energy band gaps in various bands, so that light emitting devices having various wavelength ranges can be manufactured as needed.

For example, it is advantageous for a UV light emitting element used for a backlight of a display, a sterilizing apparatus, etc. to have a wide directivity angle. Therefore, in order to widen the directivity angle of the light emitting element, a technique such as application of a further configuration such as a lens or surface treatment of the light emitting element is applied.

On the other hand, a light-emitting device of a wafer-level package or a chip-on-board type that does not use a separate package body is required to adjust the directivity angle without a separate additional configuration such as a lens. However, the conventional surface processing technique and the like can increase the light extraction efficiency of the light emitting device, but it is difficult to increase the directivity angle. Particularly, in the case of a UV light emitting device, there is a limitation in applying a technique of increasing the directivity angle because a molding part or a lens using a material that can be deformed or deteriorated by UV light can not be applied.

Therefore, in a light emitting device that does not use a package body or a lens, a technique of increasing the directivity angle is required.

A problem to be solved by the present invention is to provide a light emitting device having a wide directivity angle and a method of manufacturing the same.

Another problem to be solved by the present invention is to provide a light emitting device having a wide directivity angle without a further configuration such as a lens and a method of manufacturing the same.

A light emitting device according to an embodiment of the present invention includes: a light emitting structure; A transparent substrate positioned on the light emitting structure; And an antireflective layer covering the side surfaces of the light emitting structure and the transparent substrate, at least a part of the upper surface of the transparent substrate is exposed.

The transparent substrate may include an inclined chamfered surface formed on an upper edge thereof, and the antireflection layer may cover the chamfered surface.

Furthermore, the transparent substrate may further include a concavo-convex pattern formed on the upper surface thereof, the concavo-convex pattern having protrusions and recesses, and the antireflection layer may fill the recesses of the concavo-convex pattern.

The upper surface of the transparent substrate can be partially exposed by the projection of the uneven pattern.

Further, the concave portion may have a V shape.

The inclination of the chamfered surface may be the same as the inclination of the concave portion.

The antireflection layer may contain _{SiO 2, SiN x, SiON,} MgF 2, MgO, Si 3 N 4, Al 2 O 3, SiO, TiO 2, Ta 2 O 5, ZnS, CeO, at least one of CeO ₂ have.

Meanwhile, the light emitting structure may emit light having a peak wavelength in the ultraviolet region.

The light emitting device may further include electrodes positioned below the light emitting structure.

In some embodiments, the light emitting structure includes a first conductive semiconductor layer; A plurality of mesas spaced apart from each other below the first conductive semiconductor layer and each including an active layer and a second conductive semiconductor layer; Reflective electrodes positioned under each of the plurality of mesas to make ohmic contact with the second conductive semiconductor layer; And an ohmic contact layer covering the plurality of mesas and the first conductivity type semiconductor layer, the ohmic contact layer being located in a region below each of the mesas and having openings exposing the reflective electrodes, Lt; RTI ID = 0.0 > of < / RTI > mesas.

The plurality of mesas may have an elongated shape extending in parallel and extending in parallel with each other in one direction, and the openings of the current dispersion layer may be biased toward the same end side of the plurality of mesas.

The light emitting device further includes: an upper insulating layer covering at least a part of the current spreading layer, the upper insulating layer having openings for exposing the reflective electrodes; And a second electrode pad located on the upper insulating layer and connected to the reflective electrodes exposed through the openings of the upper insulating layer.

The light emitting device may further include a first electrode pad connected to the current dispersion layer.

According to another embodiment of the present invention, there is provided a method of manufacturing a light emitting device, comprising: preparing a light emitting structure having a transparent substrate on a top thereof; And forming an antireflection layer covering the side surfaces of the transparent substrate and the light emitting structure, wherein at least a part of the upper surface of the transparent substrate is exposed.

Preparing the light emitting structure may include forming an uneven pattern having projections and depressions on the upper surface of the transparent substrate.

In other embodiments, preparing the light emitting structure may include forming a light emitting structure on which the transparent substrate is formed by dividing a substrate having a plurality of the light emitting structures, the substrate being formed by laser scribing And a chamfered surface may be formed on the upper edge of the transparent substrate.

The concave portion of the concavo-convex pattern can be formed by using a laser during the laser scribing process.

The side inclination of the concave portion may be the same as the inclination of the chamfered surface.

The anti-reflection layer may be formed to fill the recess, and the upper surface of the projection may be exposed.

The antireflection layer may be formed using planar electron beam deposition.

The antireflection layer may contain _{SiO 2, SiN x, SiON,} MgF 2, MgO, Si 3 N 4, Al 2 O 3, SiO, TiO 2, Ta 2 O 5, ZnS, CeO, at least one of CeO ₂ have.

Meanwhile, the light emitting structure may emit light having a peak wavelength in the ultraviolet region.

According to the present invention, by including the antireflection layer and the transparent substrate having the upper surface at least partially exposed, it is possible to provide a light emitting device having a wide directivity angle and a method of manufacturing the same. Further, it is possible to provide a light emitting device that emits a substantially constant amount of light irrespective of the emission angle, and can improve the reliability of the light emitting device by providing a light emitting device having a wide directivity angle without adding any additional structure.

1 to 4 are cross-sectional views illustrating a light emitting device and a method of manufacturing the same according to an embodiment of the present invention.
5 to 7 are cross-sectional views illustrating a light emitting device and a method of manufacturing the same according to still another embodiment of the present invention.
8 to 12 are sectional views and plan views illustrating a 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. The following embodiments are provided by way of example so that those skilled in the art can sufficiently convey the spirit of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, etc. of components may be exaggerated for convenience. It is also to be understood that when an element is referred to as being "above" or "above" another element, But also includes the case where there are other components in between. Like reference numerals designate like elements throughout the specification.

1 to 4 are cross-sectional views illustrating a light emitting device and a method of manufacturing the same according to an embodiment of the present invention.

Referring to FIG. 1, a mask pattern 120 is formed on a light emitting diode 100. The light emitting diode 100 includes a light emitting structure 110 having a transparent substrate 21 formed thereon.

The light emitting diode 100 may include a light emitting structure 110 and a transparent substrate 21 disposed on the light emitting structure 110. The light emitting structure 110 may include electrodes (not shown) formed at a lower portion thereof, so that the light emitting diode 100 can be used as a wafer level package without a packaging process. The structure of the light emitting structure 110 is not limited, and may have, for example, a flip chip structure or a vertical structure. Hereinafter, an example of the light emitting diode 100 will be described with reference to Figs. 8 to 12. Fig. However, it should be understood that the present invention is not limited thereto, and the present invention will be better understood from the following description.

8 to 12 are diagrams for explaining a light emitting diode 100 and a method of manufacturing the same according to an embodiment of the present invention. In each figure, (a) is a plan view, (b) is a sectional view taken along the cutting line AA to be.

8, a first conductivity type semiconductor layer 23 is formed on a transparent substrate 21 and a plurality of mesas M spaced apart from each other are formed on the first conductivity type semiconductor layer 23, . The plurality of mesas M each include an active layer 25 and a second conductivity type semiconductor layer 27. The active layer 25 is located between the first conductivity type semiconductor layer 23 and the second conductivity type semiconductor layer 27. On the other hand, the reflective electrodes 30 are positioned on the plurality of mesas M, respectively.

The plurality of mesas M are formed on the transparent substrate 21 by depositing an epi layer including a first conductive type semiconductor layer 23, an active layer 25 and a second conductive type semiconductor layer 27 on a metal organic chemical vapor deposition (MOCVD) method, and then patterning the second conductivity type semiconductor layer 27 and the active layer 25 so that the first conductivity type semiconductor layer 23 is exposed. The sides of the plurality of mesas M may be formed obliquely by using a technique such as photoresist reflow. The inclined profile of the mesa (M) side improves the extraction efficiency of the light generated in the active layer 25.

The plurality of mesas M may have an elongated shape extending parallel to each other in one direction as shown. This shape simplifies the formation of a plurality of mesas M of the same shape in a plurality of chip areas on the transparent substrate 21. [

The reflective electrodes 30 may be formed on each of the mesas M after the plurality of mesas M are formed. However, the present invention is not limited thereto, and the second conductivity type semiconductor layer 27 may be grown It may be formed on the second conductive type semiconductor layer 27 before forming the mesas M. [ The reflective electrode 30 covers most of the upper surface of the mesa M and has substantially the same shape as the planar shape of the mesa M. [

The reflective electrodes 30 may include a reflective layer 28 and may further include a barrier layer 29 and the barrier layer 29 may cover the top and sides of the reflective layer 28. For example, the barrier layer 29 may be formed to cover the upper surface and the side surface of the reflective layer 28 by forming a pattern of the reflective layer 28 and forming a barrier layer 29 thereon. For example, the reflective layer 28 may be formed by depositing and patterning Ag, Ag alloy, Ni / Ag, NiZn / Ag, and TiO / Ag layers. On the other hand, the barrier layer 29 may be formed of Ni, Cr, Ti, Pt or a composite layer thereof to prevent diffusion or contamination of the metal material of the reflection layer.

After the plurality of mesas M are formed, the edges of the first conductive type semiconductor layer 23 may also be etched. Thus, the upper surface of the transparent substrate 21 can be exposed. The side surfaces of the first conductivity type semiconductor layer 23 may also be inclined.

The plurality of mesas M may be formed to be confined within the upper region of the first conductivity type semiconductor layer 23 as shown in FIG. That is, a plurality of mesas M may be located on the upper region of the first conductivity type semiconductor layer 23 in an island shape.

Referring to FIG. 9, a lower insulating layer 31 covering the plurality of mesas M and the first conductive semiconductor layer 23 is formed. The lower insulating layer 31 has openings 31a and 31b for allowing electrical connection to the first conductivity type semiconductor layer 23 and the second conductivity type semiconductor layer 27 in a specific region. For example, the lower insulating layer 31 may have openings 31a for exposing the first conductivity type semiconductor layer 23 and openings 31b for exposing the reflective electrodes 30.

The openings 31a may be located near the edge between the mesa M and the transparent substrate 21 and may have an elongated shape extending along the mesa M. [ On the other hand, the openings 31b are located on the upper portion of the mesa M and are biased to the same end side of the mesa.

The lower insulating layer 31 may be formed of an oxide film such as SiO ₂ , a nitride film such as SiN _x, or an insulating film of MgF ₂ using a technique such as chemical vapor deposition (CVD) or electron beam evaporation. The lower insulating layer 31 may be formed of a single layer, but is not limited thereto and may be formed of multiple layers. Further, the lower insulating layer 31 may be formed of a distributed Bragg reflector (DBR) in which a low refractive index material layer and a high refractive index material layer are alternately laminated. For example, an insulating reflection layer having a high reflectance can be formed by laminating SiO ₂ / TiO ₂ or SiO ₂ / Nb ₂ O ₅ layers.

Referring to FIG. 10, a current spreading layer 33 is formed on the lower insulating layer 31. The current spreading layer 33 covers the plurality of mesas M and the first conductivity type semiconductor layer 23. In addition, the current spreading layer 33 has openings 33a located in the respective upper portions of the mesa M and exposing the reflective electrodes. The current spreading layer 33 may be in ohmic contact with the first conductive semiconductor layer 23 through the openings 31a of the lower insulating layer 31. [ The current spreading layer 33 is insulated from the plurality of mesas M and the reflective electrodes 30 by the lower insulating layer 31.

The openings 33a of the current spreading layer 33 are formed to have a larger area than the openings 31b of the lower insulating layer 31 so as to prevent the current spreading layer 33 from being connected to the reflective electrodes 30. [ Respectively. Therefore, the side walls of the openings 33a are located on the lower insulating layer 31. [

The current spreading layer 33 is formed on almost the entire region of the substrate 31 except for the openings 33a. Therefore, the current can be easily dispersed through the current dispersion layer 33. The current spreading layer 33 may include a highly reflective metal layer such as an Al layer and the highly reflective metal layer may be formed on an adhesive layer such as Ti, Cr, or Ni. Further, a protective layer of a single layer or a multiple layer structure such as Ni, Cr, Au or the like may be formed on the highly reflective metal layer. The current spreading layer 33 may have a multilayer structure of Ti / Al / Ti / Ni / Au, for example.

Referring to FIG. 11, an upper insulating layer 35 is formed on the current spreading layer 33. The upper insulating layer 35 has openings 35b for exposing the reflective electrodes 30 together with openings 35a for exposing the current spreading layer 33. [ The opening 35a may have an elongated shape in a direction perpendicular to the longitudinal direction of the mesa M and has a relatively large area as compared with the openings 35b. The openings 35b expose the exposed reflective electrodes 30 through the openings 33a of the current spreading layer 33 and the openings 31b of the lower insulating layer 31. [ The openings 35b may have a smaller area than the openings 33a of the current spreading layer 33 and may have a larger area than the openings 31b of the lower insulating layer 31. [ Accordingly, the sidewalls of the openings 33a of the current-spreading layer 33 may be covered with the upper insulating layer 35.

The upper insulating layer 35 may be formed using an oxide insulating layer, a nitride insulating layer, or a polymer such as polyimide, Teflon, or parylene.

Referring to FIG. 12, a first pad 37a and a second pad 37b are formed on the upper insulating layer 35. Referring to FIG. The first pad 37a is connected to the current spreading layer 33 through the opening 35a of the upper insulating layer 35 and the second pad 37b is connected to the openings 35b of the upper insulating layer 35 To the reflective electrodes 30. The first pad 37a and the second pad 37b may be used as a pad for connecting the bump or a pad for SMT in order to mount the light emitting diode on a submount, a package, a printed circuit board or the like.

The first and second pads 37a and 37b may be formed together in the same process and may be formed using, for example, a photo and etch technique or a lift-off technique. The first and second pads 37a and 37b may include, for example, an adhesive layer of Ti, Cr, Ni, or the like and a high-conductivity layer of metal such as Al, Cu, Ag, or Au.

Thereafter, the light-emitting diode 100 is completed by dividing the transparent substrate 21 into individual light-emitting diode chip units. At this time, the transparent substrate 21 may be divided using a scribing process, for example, a laser scribing process may be used. When separating the transparent substrate 21 using laser scribing, a chamfered surface may be formed on the upper edge of the transparent substrate 21. The chamfered surface may have an inclined side surface. Although not shown in FIG. 12, the chamfered surface 211 may be formed at an upper corner of the transparent substrate 21 as shown in FIG.

Hereinafter, a structure of a light emitting diode 100 according to an embodiment of the present invention will be described in detail with reference to FIG.

The light emitting diode includes a transparent substrate 21, a lower insulating layer 31, a first conductive semiconductor layer 23, a mesa M, reflective electrodes 30, and a current dispersion layer 33. An upper insulating layer 35, and a first pad 37a and a second pad 37b.

The transparent substrate 21 may be a growth substrate for growing gallium nitride epilayers, for example, sapphire, silicon carbide, silicon, or a gallium nitride substrate. In this embodiment, the transparent substrate 21 may be a sapphire substrate have.

The first conductivity type semiconductor layer 23 is continuous and a plurality of mesas M are disposed on the first conductivity type semiconductor layer 23 so as to be spaced apart from each other. The mesas M include the active layer 25 and the second conductivity type semiconductor layer 27 as described with reference to FIG. 1 and have an elongated shape extending toward one side. Here, the mesas M are stacked layers of gallium nitride compound semiconductors. The mesa M may be located within the upper region of the first conductivity type semiconductor layer 23 as shown in FIG.

The first conductive semiconductor layer 23, the active layer 25, and the second conductive semiconductor layer 27 may include a nitride semiconductor. The first conductive semiconductor layer 23 may be an n-type semiconductor layer, the second conductive semiconductor layer 27 may be a p-type semiconductor layer, or vice versa. Meanwhile, the active layer 25 may include a nitride semiconductor, and the peak wavelength of light emitted from the active layer 25 may be determined by adjusting the composition ratio of the nitride semiconductor. In particular, in the present embodiment, the active layer 25 can emit light having a peak wavelength in the ultraviolet region.

Each of the reflective electrodes 30 is located on the plurality of mesas M and ohmically contacts the second conductive type semiconductor layer 27. The reflective electrodes 300 may include a reflective layer 28 and a barrier layer 29 as described with reference to Figure 1 and a barrier layer 29 may cover the top and sides of the reflective layer 28.

The current spreading layer 33 covers the plurality of mesas M and the first conductivity type semiconductor layer 23. The current spreading layer 33 has openings 33a that are located in the respective upper portions of the mesa M and expose the reflective electrodes 30. [ The current spreading layer 33 is also in ohmic contact with the first conductivity type semiconductor layer 23 and is insulated from the plurality of mesas M. [ The current spreading layer 33 may include a reflective metal such as Al.

The current spreading layer 33 may be insulated from the plurality of mesas M by a lower insulating layer 31. For example, the lower insulating layer 31 may be positioned between the plurality of mesas M and the current spreading layer 33 to isolate the current spreading layer 33 from the plurality of mesas M . The lower insulating layer 31 may have openings 31b that are located in the respective upper portions of the mesa M and expose the reflective electrodes 30. The lower insulating layer 31 may have openings 31b, (Not shown). The current spreading layer 33 may be connected to the first conductivity type semiconductor layer 23 through the openings 31a. The openings 31b of the lower insulating layer 31 have a smaller area than the openings 33a of the current spreading layer 33 and are all exposed by the openings 33a.

The upper insulating layer 35 covers at least a part of the current-spreading layer 33. The upper insulating layer 35 has openings 35b for exposing the reflective electrodes 30. Furthermore, the upper insulating layer 35 may have an opening 35a for exposing the current-spreading layer 33. [ The upper insulating layer 35 may cover the sidewalls of the openings 33a of the current spreading layer 33.

The first pad 37a may be located on the current spreading layer 33 and may be connected to the current spreading layer 33 through the opening 35a of the upper insulating layer 35, for example. The second pad 37b is connected to the reflective electrodes 30 exposed through the openings 35b.

According to the present invention, the current-spreading layer 33 covers almost the entire region of the first conductivity type semiconductor layer 23 between the mesas M and the mesas M. [ Therefore, the current can be easily dispersed through the current dispersion layer 33. [

The current dispersion layer 23 includes a reflective metal layer such as Al or the lower insulating layer is formed of an insulating reflection layer so that the light that is not reflected by the reflective electrodes 30 is separated from the current dispersion layer 23 or the lower insulating layer 23. [ Layer 31, so that the light extraction efficiency can be improved.

In the present invention, the light emitting diode 100 described above can be used, but the present invention is not limited thereto.

Referring again to FIG. 1, a mask pattern 120 is formed on the transparent substrate 21, so that the upper surface of the transparent substrate 21 is partially exposed to the opening 121 of the mask pattern 120. The mask pattern 120 may comprise a photoresist.

The transparent substrate 21 may include a chamfered surface 211 formed at an upper corner of the transparent substrate 21. The chamfered surface 211 may be formed in the scribing process when the transparent substrate 21 is divided. However, the present invention is not limited thereto, and the chamfered surface 211 may be formed through a separate etching process.

Referring to FIG. 2, an uneven pattern having protrusions 215 and recesses 213 is formed on the upper surface of the transparent substrate 21.

The concave-convex pattern may be formed by an etching process using the mask pattern 120 as an etching mask, for example, a dry etching process. Accordingly, the upper surface of the transparent substrate 21 under the opening 121 is etched to form the concave portion 213. The concave portion 213 may be formed to have various shapes depending on the shape of the mask pattern 120. For example, as shown in FIG. 2, the concave portion 213 may have a V-shaped shape whose sides are inclined.

In the above description, the concavo-convex pattern is formed through a separate etching process. Alternatively, the concavo-convex pattern may be simultaneously formed in the process of forming the transparent substrate 21 to form the light emitting diode 100. Specifically, in the case of dividing the transparent substrate 21 using the laser scribing process, a laser is applied to the upper surface of the transparent substrate 21 in the area of each light emitting diode 100 in addition to the area where the transparent substrate 21 is divided The laser is also applied. Accordingly, the concave portion 215 can be formed in the region where the laser is applied. The concave portion 215 formed at the same time as the dividing step of the transparent substrate 21 may have a V shape and the inclination of the side surface may be the same as the inclination of the chamfer surface 211. [ The concave portions 213 of the concave-convex pattern are simultaneously formed in the step of dividing the light emitting diode 100, whereby the etching process for forming the concave-convex pattern can be omitted. Thus, the process can be simplified.

3 and 4, an antireflection layer 130 is formed to cover the side surface of the transparent substrate 21, the side surface of the light emitting structure 110, and fill the concave portion 215.

Referring to FIG. 3, an antireflective material 130a covering the upper and side surfaces of the transparent substrate 21, the side surface of the light emitting structure 110, and the mask pattern 120 may be formed.

The anti-reflection material 130a may have a refractive index smaller than that of the transparent substrate 21 and larger than the refractive index of _air (n _air = 1). For example, the anti-reflective material (130a) is a SiO ₂ (n _SiO2 = about 1.45) may include, further, SiO _2, SiN _x, SiON, MgF _2, MgO, Si ₃ N _4, Al ₂ O ₃ , SiO, TiO ₂ , Ta ₂ O ₅ , ZnS, CeO, and CeO ₂ . The anti-reflection material 130a may be formed using various deposition methods, and in particular, may be formed using a planetary E-beam. It is possible to easily form the antireflection material 130a on the side surfaces of the transparent substrate 21 and the light emitting structure 110 by forming the antireflection material 130a using the planetary electron beam deposition.

4, the anti-reflection layer 130 is formed by performing a lift-off process to remove the anti-reflective material 130a on the mask pattern 120 by removing the mask pattern 120. Referring to FIG. Thus, a light emitting element as shown in Fig. 4 is provided.

Although not shown, the light emitting structure 110 may further include electrodes formed on a bottom surface thereof.

The antireflection layer 130 may cover the sides of the light emitting structure 110 and the transparent substrate 21 and also fill the recesses 215. [ The upper surface of the protrusion 213 can be exposed. Since the antireflection layer 130 has such a configuration, the light emitting element can have a wide directivity angle. This will be described in detail.

The antireflection layer 130 has a refractive index that is smaller than the refractive index of the transparent substrate 21 and larger than the refractive index of air, thereby preventing total internal total reflection of the light emitting device. For example, if the transparent substrate 21 is a sapphire substrate (n _sapphire = about 1.77), the light passing through the antireflective layer 130 has a total reflection critical angle greater than light directly directed to the air in the sapphire substrate.

Therefore, the ratio of the light emitted to the side surface of the light emitting element can be increased to have a wide directivity angle. In addition, since the antireflection layer 130 is formed only on the concave portion 215 formed on the upper surface of the transparent substrate 21, light directed to the upper surface of the protrusion 213 is totally reflected, Probability increases. Further, by having the inclined portion 215 having a sloped side, the probability that the light emitted from the light emitting element is directed more toward the side than the vertical direction is further increased. Accordingly, the light emitting device of the present invention can emit uniform light over the whole angle of light emission, while having a wide directivity angle. That is, the brightness can be kept substantially constant regardless of the emission angle.

According to the present embodiment, it is possible to emit a constant light regardless of the wide directivity angle and the light emission angle only by the light emitting element, without adding any additional configuration to the light emitting element. In particular, when manufacturing an ultraviolet light-emitting device which can realize a wide directivity angle only by using a light-emitting element and can not use a lens or the like that can be deteriorated by ultraviolet rays, a light-emitting device with improved reliability can be provided.

5 to 7 are cross-sectional views illustrating a light emitting device and a method of manufacturing the same according to still another embodiment of the present invention. The detailed description of the same configuration as described in the above embodiments will be omitted.

Referring to FIG. 5, a mask 140 is formed on the light emitting diode 100. The light emitting diode 100 includes a light emitting structure 110 having a transparent substrate 21 formed thereon.

The mask 140 may be formed to cover the upper surface of the transparent substrate 21 and may include a photoresist. On the other hand, the chamfer surface 211 can be exposed without being covered with the mask 140.

6, an anti-reflection material 150a is formed to cover the mask 140, the side surface of the transparent substrate 21, and the side surface of the light emitting structure 110. [ An antireflective material (150a) is a _{SiO 2, SiN x, SiON,} MgF 2, MgO, Si 3 N 4, Al 2 O 3, SiO, TiO 2, Ta 2 O 5, ZnS, CeO, at least one of CeO ₂ And may be formed using planetary electron beam deposition.

7, the mask 140 and the antireflective material 150a on the mask 140 are removed. Thereby, a light emitting element as shown in Fig. 7 is provided.

The light emitting device includes a light emitting structure 110, a transparent substrate 21 positioned on the light emitting structure 110, and a reflection preventing layer 150 covering the side surfaces of the light emitting structure 110 and the transparent substrate 21, , The upper surface of the transparent substrate 21 is exposed.

Accordingly, the total reflection of light toward the side surface of the light emitting element is reduced, and the amount of light emitted to the side surface can be increased. Further, since the probability that light is totally reflected at the interface between the upper surface of the transparent substrate 21 and the air is higher than the probability that light is totally reflected at the side of the light emitting device, a higher ratio of light can be emitted to the side of the device. Accordingly, the directivity angle of the light emitting device can be widened, and a substantially uniform light intensity can be maintained over the entire light emitting angle.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims (22)

A light emitting structure;
A transparent substrate positioned on the light emitting structure; And
And an anti-reflection layer covering the side surfaces of the light emitting structure and the transparent substrate, wherein at least a part of the upper surface of the transparent substrate is exposed. The method according to claim 1,
Wherein the transparent substrate includes an inclined chamfered surface formed at an upper edge thereof,
And the antireflection layer covers the chamfered surface. The method of claim 2,
The transparent substrate further includes a concavo-convex pattern formed on an upper surface thereof, the concavo-convex pattern having a protruding portion and a concave portion,
And the antireflection layer fills the concave portion of the concavo-convex pattern. The method of claim 3,
And the upper surface of the transparent substrate is partially exposed by the projection of the concave-convex pattern. The method of claim 3,
And the concave portion has a V-shape. The method of claim 5,
And the inclination of the chamfered surface is equal to the inclination of the concave portion. The method according to claim 1,
Wherein the antireflection layer comprises at least one of SiO ₂ , SiN _x , SiON, MgF ₂ , MgO, Si ₃ N ₄ , Al ₂ O ₃ , SiO, TiO ₂ , Ta ₂ O ₅ , ZnS, CeO, CeO ₂ device. The method according to claim 1,
Wherein the light emitting structure emits light having a peak wavelength in an ultraviolet region. The method according to claim 1,
Further comprising electrodes positioned below the light emitting structure. The method according to claim 1,
The light-
A first conductive semiconductor layer;
A plurality of mesas spaced apart from each other below the first conductive semiconductor layer and each including an active layer and a second conductive semiconductor layer;
Reflective electrodes positioned under each of the plurality of mesas to make ohmic contact with the second conductive semiconductor layer; And
And a second conductive semiconductor layer formed on the first conductive semiconductor layer, wherein the first conductive semiconductor layer and the second conductive semiconductor layer are formed on the first conductive semiconductor layer, And a current spreading layer insulated from the mesas. The method of claim 10,
Wherein the plurality of mesas have an elongated shape extending parallel and extending in one direction, and the openings of the current dispersion layer are biased toward the same end side of the plurality of mesas. The method of claim 10,
An upper insulating layer covering at least a part of the current spreading layer, the upper insulating layer having openings for exposing the reflective electrodes; And
And a second electrode pad located on the upper insulating layer and connected to the reflective electrodes exposed through the openings of the upper insulating layer. The method of claim 12,
And a first electrode pad connected to the current dispersion layer. Preparing a light emitting structure on which a transparent substrate is formed;
And forming an antireflection layer covering the side surfaces of the transparent substrate and the light emitting structure,
Wherein at least a part of the upper surface of the transparent substrate is exposed. 15. The method of claim 14,
In preparing the light emitting structure,
And forming an uneven pattern having projections and depressions on the upper surface of the transparent substrate. The method according to claim 14 or 15,
In preparing the light emitting structure,
And forming a light emitting structure having the transparent substrate formed thereon by dividing a substrate having a plurality of the light emitting structures,
Wherein the substrate is divided using laser scribing, and a chamfered surface is formed on an upper edge of the transparent substrate. 18. The method of claim 16,
Wherein the concave portion of the concavo-convex pattern is formed by using a laser during a laser scribing process. 18. The method of claim 17,
Wherein the side inclination of the concave portion is equal to the inclination of the chamfered surface. 16. The method of claim 15,
Wherein the antireflection layer is formed to fill the concave portion, and an upper surface of the protrusion is exposed. 15. The method of claim 14,
Wherein the antireflection layer is formed using planar electron beam deposition. 15. The method of claim 14,
Wherein the antireflection layer comprises at least one of SiO ₂ , SiN _x , SiON, MgF ₂ , MgO, Si ₃ N ₄ , Al ₂ O ₃ , SiO, TiO ₂ , Ta ₂ O ₅ , ZnS, CeO, CeO ₂ Lt; / RTI > 15. The method of claim 14,
Wherein the light emitting structure emits light having a peak wavelength in an ultraviolet region.

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