KR20150020418A - Light emitting device and method of fabricating the same - Google Patents

Abstract

The present invention provides a light emitting device and a method for manufacturing the same. The light emitting device includes: a first conductive base layer; a mask layer which is located on the first conductive base layer and includes a plurality of opening units; a plurality of light emitting structures which is located on the opening units and is separated from each other; and a current leakage prevention layer which covers partially the upper side of the light emitting structures. Accordingly, the light emitting device minimizes the generation of the current leakage.

Description

TECHNICAL FIELD [0001] The present invention relates to a light emitting device,

The present invention relates to a light emitting device and a method of manufacturing the same, and more particularly, to a light emitting device and a method of manufacturing the same that can minimize the occurrence of leakage current.

BACKGROUND ART [0002] Light emitting devices are inorganic semiconductor devices that emit light generated by recombination of electrons and holes. Recently, they are used in various fields such as displays, automobile lamps, and general lighting. Since the light emitting device has a long lifetime, low power consumption, and a high response speed, the light emitting device package including the light emitting diode is expected to replace the conventional light source.

The light emitting device uses a principle in which energy released in the transition process of electrons is released as light energy when holes of the p-type semiconductor layer and electrons of the n-type semiconductor layer are combined. Therefore, a typical light emitting device has a structure including an n-type semiconductor layer, a p-type semiconductor layer, and an active layer interposed between the n-type and p-type semiconductor layers.

In general, a general light emitting device is manufactured using a nitride semiconductor such as (Al, Ga, In) N, and is manufactured by successively growing an n-type nitride semiconductor layer, an active layer, and a p-type nitride semiconductor layer on a growth substrate. In particular, a c-plane ((0001)) sapphire substrate is most widely used as a growth substrate. Meanwhile, since the nitride semiconductor grown on the c-plane sapphire substrate grows along the growth surface of the sapphire substrate, it grows along the c-plane direction. Since the nitride semiconductor in the c-plane direction has polarity, the nitride semiconductor formed along the c-plane direction forms a spontaneous polarization in the [0001] direction. Also, there is a limit to increase the internal quantum efficiency due to the quantum confined stark effect due to the internal strain piezoelectric field formed by the lattice mismatching of the active layer.

In order to solve the problems of such a polar nitride semiconductor, a method of manufacturing a light emitting device using a non-polar or semi-polar nitride semiconductor has been researched and developed. The nonpolar or semi-polar nitride-based semiconductor becomes electrically neutral, so that the deterioration of the internal quantum efficiency due to the quantum confinement stark effect or the like can be minimized. In order to produce a non-polar or semi-polar light-emitting device, a nitride-based semiconductor must be grown along a non-polar or semi-polar growth surface such as an a-plane or an m-plane. In order to grow such a nonpolar or semi-polar nitride-based semiconductor, it is necessary to use a sapphire substrate having another growth surface or to grow it using the same type of substrate (for example, a GaN substrate or an AlN substrate) The price of c-plane sapphire substrate is very high, which increases the overall process cost. In addition, due to the limitations of the present technology, the crystallinity of the non-polar or semipolar nitride-based semiconductor is much lower than that of the c-plane nitride-based semiconductor.

Thus, a method of producing a semi-polar active layer by growing nitride-based semiconductor layers having polygonal horns on an n-type nitride-based base layer grown on a c-plane sapphire substrate by selective epitaxial growth has been studied. However, the light emitting device having such a structure has a problem that leakage of current occurs at apex of a polygonal pyramid.

A problem to be solved by the present invention is to provide a light emitting device in which leakage current is minimized.

A further object of the present invention is to provide a method of manufacturing a light emitting device having a structure capable of minimizing the generation of leakage current.

A light emitting device according to an embodiment of the present invention includes: a first conductive base layer; A mask layer located on the first conductive base layer and including a plurality of openings; A plurality of light emitting structures located on the plurality of openings and spaced apart from each other; And a leakage current blocking layer partially covering an upper portion of the plurality of light emitting structures.

Each of the plurality of light emitting structures may include a tip portion or an end portion formed on the upper portion, and the area of the end portion may be smaller than the area of the lower surface of the light emitting structure.

In addition, the leakage current prevention layer may cover the tip portion or the end portion.

Each of the plurality of light emitting structures may be in the form of at least one of a hexagon, a hexagon, a hexagon, and a polyhedron.

In other embodiments, each of the plurality of light emitting structures may include an inclined side surface, and the inclined side surface may have an inclination angle of 60 to 65 degrees with respect to an upper surface of the first conductive type base layer.

The plurality of light emitting structures may partially cover the mask layer.

The leakage current blocking layer may include at least one of silicon oxide and silicon nitride.

In some embodiments, each of the plurality of light emitting structures includes: a first conductive semiconductor layer; An active layer covering the first conductivity type semiconductor layer; And a second conductive semiconductor layer covering the active layer.

The light emitting device may further include a transparent electrode covering the plurality of light emitting structures, the leakage current blocking layer, and the mask layer, and electrically contacting the side surfaces of the plurality of light emitting structures.

Furthermore, the light emitting device may further include an insulating layer interposed between the mask layer and the transparent electrode, filling the spaces between the plurality of light emitting structures.

In addition, the light emitting device may further include a region where an upper surface of the first conductive base layer is exposed, a first electrode located on the exposed region, and a second electrode located on the transparent electrode.

The width of the openings may be 200 nm to 20 μm, and the spacing between the openings may be 500 nm to 50 μm.

A method of manufacturing a light emitting device according to another embodiment of the present invention includes: forming a first conductive base layer on a substrate; Forming a mask layer including a plurality of openings on the first conductive base layer; Forming a plurality of spaced apart light emitting structures on the openings; And forming a leakage current prevention layer partially covering an upper surface of the plurality of light emitting structures.

Each of the plurality of light emitting structures may include a tip portion or an end portion formed at an upper portion thereof. The area of the tip portion or the end portion may be smaller than the area of the lower surface of the light emitting structure, Growth can be accompanied by growth.

The formation of the leakage current prevention layer may include forming a photoresist that at least partially covers the plurality of light emitting structures and the mask layer, exposing the leading end or the end portion; Forming the photoresist and an insulating material covering the tip or end; And removing the photoresist and the insulating material formed on the photoresist.

Each of the plurality of light emitting structures may be in the form of at least one of a hexagon, a hexagon, a hexagon, and a polyhedron.

Each of the plurality of light emitting structures may include an inclined side surface, and the inclined side surface may have an inclination angle of 60 to 65 degrees with respect to an upper surface of the first conductive base layer.

In some embodiments, forming the light emitting structure comprises: growing the first conductive type semiconductor layer by seeding the first conductive type base layer exposed in the opening portion; Growing an active layer covering the first conductive semiconductor layer; And growing a second conductive type semiconductor layer covering the active layer. The first conductive type semiconductor layer may further include a growth surface different from a growth surface of the first conductive type base layer.

The manufacturing method may further include forming the plurality of light emitting structures, the leakage current prevention layer, and the transparent electrode covering the mask layer.

The manufacturing method may further include forming an insulating layer partially filling the space between the plurality of light emitting structures and exposing a side surface of the plurality of light emitting structures before forming the transparent electrode.

According to the present invention, it is possible to minimize the occurrence of leakage current of the light emitting element by forming the leakage current prevention layer covering the tip portion or the end portion of the light emitting structure. In addition, it is possible to effectively prevent the leakage current and to prevent the decrease in the luminous efficiency, and to improve the reliability of the luminous element.

In addition, it is possible to provide a method for effectively manufacturing the light emitting device.

1 is a cross-sectional view illustrating a light emitting device according to an embodiment of the present invention.
FIGS. 2 to 8 are cross-sectional views illustrating a method of manufacturing a light emitting device according to another embodiment of the present invention.
9 is a graph for comparing the voltage-current characteristics of the light emitting device according to the present invention with a comparative example.

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

Referring to FIG. 1, the light emitting device includes a first conductive base layer 120, a mask layer 130, a plurality of light emitting structures 140, and a current leakage preventing layer 150. Furthermore, the light emitting device may further include a substrate 110, an insulating layer 160, and a transparent electrode 170.

The substrate 110 is not limited as long as it can grow the semiconductor layers of the present invention, and may be, for example, a sapphire substrate, a silicon carbide substrate, a silicon substrate, a glass substrate, or a nitride substrate. Particularly, in the present embodiment, the substrate 110 may be a sapphire substrate whose growth surface is the c-plane ((0001)). However, the present invention is not limited thereto.

The first conductive base layer 120 may be located on the substrate 110. The first conductive base layer 120 may include a nitride semiconductor such as (Al, Ga, In) N, and may further include an n-type impurity such as Si or a p-type impurity such as Mg, Type or p-type conductivity. For example, the first conductive base layer 120 may comprise n-type GaN. Further, the first conductive base layer 120 may be formed as a single layer or multiple layers, and may include a superlattice layer.

Meanwhile, a buffer layer (not shown) may be interposed between the substrate 110 and the first conductive base layer 120. The buffer layer may alleviate the lattice constant between the substrate 110 and the first conductive base layer 120. In addition, when the substrate 110 is a heterogeneous substrate such as a sapphire substrate, the buffer layer can serve as a nucleus layer so that the first conductive base layer 120 can be grown on the substrate 110.

The mask layer 130 may be located on the first conductive base layer 120 and may include a plurality of openings. By including the plurality of openings in the mask layer 130, the mask layer 130 can partially cover the top surface of the first conductive base layer 120. The plurality of openings in the mask layer 130 may have various shapes and may be, for example, in a circular or polygonal shape. Further, the plurality of openings of the mask layer 130 may have a diameter or width of 200 nm to 20 占 퐉, and a spacing distance between the openings may be 500 nm to 50 占 퐉.

The formation position and shape of the plurality of light emitting structures 140 to be described later can be determined according to the shape, diameter, or spacing distance of the plurality of openings. Accordingly, the shape, diameter, or spacing of the plurality of openings may be variously selected according to the plurality of light emitting structures 140 to be obtained.

The mask layer 130 may comprise an insulating material, for example, may include at least one of silicon nitride, such as silicon oxide, such as SiN _x and SiO _2.

The plurality of light emitting structures 140 may be positioned on the plurality of openings and may be disposed apart from each other. Accordingly, the mask layer 130 can be partially exposed between the plurality of the light emitting structures 140. Further, as shown in FIG. 1, each of the plurality of light emitting structures 140 may partially cover the mask layer 130 around the opening.

Each of the plurality of light emitting structures 140 may include a tip portion or an end portion formed at an upper portion thereof. The area of the lower surface of each light emitting structure 140 may be smaller than the area of the end portion or the tip portion. Accordingly, each of the light emitting structures 140 may include an inclined side surface, and the inclined side surface may have an inclination angle of 60 to 65 degrees with respect to the upper surface of the first conductive base layer 120. In addition, each of the light emitting structures 140 may have a shape of at least one of hexagonal, hexagonal, hexagonal, and polyhedral. For example, each light emitting structure 140 has a hexagonal shape, so that its cross section may be triangular as shown in FIG. The shape of the light emitting structure 140 may be obtained by using a selective epitaxial growth method or a non-surfactant method in forming the light emitting structure 140, but the present invention is not limited thereto . This will be described in detail later.

Each of the plurality of light emitting structures 140 includes a first conductive semiconductor layer 141, an active layer 143 covering the first conductive semiconductor layer 141, and a second conductive semiconductor layer 140 covering the active layer 143 145). Therefore, only the second conductive semiconductor layer 145 may be exposed on the surface of each of the plurality of the light emitting structures 140.

The first conductivity type semiconductor layer 141, the active layer 143 and the second conductivity type semiconductor layer 145 may include a nitride semiconductor such as (Al, Ga, In) N. The first conductive semiconductor layer 141 may include n-type impurities and may be doped to the n-type. The second conductive semiconductor layer 145 may include p-type impurities to be doped to the p-type, Lt; / RTI > For example, the first conductive semiconductor layer 141 may include n-type GaN, and the second conductive semiconductor layer 143 may include p-type GaN. The active layer 143 may include a single quantum well structure or a multiple quantum well structure. For example, the active layer 143 may be formed by repeatedly laminating an InGaN layer as a well layer and a GaN layer as a barrier layer. The composition of the nitride-based semiconductor constituting the active layer 143 can be selectively controlled according to the peak wavelength of light to be emitted through the light emitting device. Hereinafter, a detailed description of technical details known to a person having ordinary skill in the art (hereinafter referred to as "a typical technician") with respect to the light emitting structure 140 including a nitride semiconductor is omitted.

The interface between the first conductivity type semiconductor layer 141 and the active layer 143, the interface between the active layer 143 and the second conductivity type semiconductor layer 145, or the surface of the second conductivity type semiconductor layer 145, Plane. For example, when the semiconductor layers 141, 143, and 145 of the light emitting structure 140 include nitride-based semiconductors and the growth surface of the first conductive base layer 120 is the c plane (0001) , The interfaces or the surface of the second conductivity type semiconductor layer 145 may include a (1122) plane, which is a semipolar plane. Further, the interfaces or the surface of the second conductivity type semiconductor layer 145 may include the family plane {1122} of the (1122) plane. Accordingly, each of the light emitting structures 140, particularly, the active layer 143 can have a semi-polarity, and the decrease of the internal quantum efficiency due to the spontaneous polarization and the piezoelectric polarization can be minimized. In addition, the shape of the light emitting structure 140 may be determined based on the crystallographic plane, and may have a hexagonal shape, a hexagonal hexagonal shape, or a polygonal shape, as described above. However, the present invention is not limited thereto, and the interface may include a non-polar surface as well as a non-polar surface or a polar surface.

On the other hand, in one light emitting structure 140, the mole fraction of In contained in the active layer 143 may vary depending on the crystallographic plane. For example, when the light emitting structure 140 has a hexagonal or hexagonal hexagonal cone shape, the active layer 143 portion on the region corresponding to the leading end or the end portion is in contact with the active layer 143 on the region corresponding to the edge It can have a high In mole fraction. Accordingly, it can be manufactured to emit light having various peak wavelengths in one light emitting structure 140.

The current leakage preventing layer 150 may partially cover the upper portion of the plurality of light emitting structures 140 and may cover a tip portion or an end portion formed on the upper portion of the light emitting structure 140.

The current leakage preventing layer 150 may have an insulating property and may include at least one of, for example, a silicon oxide such as SiO ₂ and a silicon nitride such as SiN _x . The current leakage preventing layer 150 may be formed to have a shape corresponding to the upper surface of the light emitting structure 140 and may cover an area in the form of a vertex such as the tip or end of the light emitting structure 140 in particular. For example, as shown in FIG. 1, when the light emitting structure 140 has a hexagonal shape, the current leakage preventing layer 150 may be formed to cover the vertex portion of the hexagonal horn. The current leakage preventing layer 150 may have a thickness of 50 to 300 nm, which may be selectively applied depending on the size of the device and the like.

In the light emitting device, since the v-pit formed on the surface of the semiconductor layer has a high defect density and a high energy, there is a high probability that current leakage occurs along this portion. Also in this embodiment, by forming a semi-polar or non-polar surface, for example, a structure similar to a v-pit like the vertex of the hexagonal horn of FIG. 1 is formed. By covering the portion where such current leakage can occur with the current leakage preventing layer 150, it is possible to prevent a decrease in luminous efficiency due to current leakage.

On the other hand, the current leakage preventing layer 150 is not limited to covering only the vertices of the hexagonal horn as shown in FIG. 1, and may be formed to cover a portion where current leakage may occur in various embodiments.

The transparent electrode 170 may be positioned on the first conductive base layer 120 and may be formed to cover the plurality of the light emitting structure 140, the leakage current blocking layer 150, and the mask layer 130. The transparent electrode 170 may be in contact with the second conductive semiconductor layer 145 of each light emitting structure 140.

The transparent electrode 170 may include an ITO (Indium Tin Oxide), ZnO (Zinc Oxide), or the like, for example, a material having high light transmittance and forming ohmic contact with the second conductive type semiconductor layer 145. [ , Aluminum Zinc Oxide (AZO), and Indium Zinc Oxide (IZO). The transparent electrode 170 may be integrally formed on the first conductive base layer 120 so that the second conductive semiconductor layers 145 of the plurality of the light emitting structures 140 are electrically connected to the transparent electrode 170, As shown in FIG.

The insulating layer 160 may fill the space between the plurality of light emitting structures 140 and may also be interposed between the mask layer 130 and the transparent electrode 170.

The insulating layer 160 may comprise a transparent polymeric material and may include, for example, photoresist such as SU8 or AZ 5214, or BCB (Benzo Cyclo Butene). However, the present invention is not limited thereto. The insulating layer 160 is interposed between the transparent electrode 170 and the mask layer 130 so that the current flowing in the transparent electrode 170 can prevent the current leakage due to conduction of the mask layer 130.

The light emitting device includes a first electrode (not shown) electrically connected to the first conductive base layer 120 and the first conductive semiconductor layer 141, and a second electrode electrically connected to the second conductive semiconductor layer 145 electrically And a second electrode (not shown) connected to the second electrode.

The light emitting device may further include a region where a surface of the first conductive base layer 120 is exposed, and the first electrode may be located on the exposed region. Accordingly, the first electrode may be electrically connected to the first conductive base layer 120, and may serve to supply external power to the first conductive base layer 120.

The second electrode may be positioned on one side of the transparent electrode 170 and electrically connected to the transparent electrode 170. Accordingly, the second electrode may serve to supply external power to the transparent electrode 170 and the second conductive type semiconductor layer 145.

However, the present invention is not limited thereto, and the positions and connection forms of the electrodes may be variously selectively applied. For example, a via hole may be formed in the substrate 110 to form a first electrode under the light emitting device, and the substrate 110 may be separated from the first conductive base layer 120 to form a first conductive base layer The first electrode may be formed under the first electrode 120. That is, the present invention is not limited to the horizontal flat-type light-emitting element described in this embodiment, and can be applied to various types of light-emitting elements having various structures such as a vertical type or a flip chip type within the spirit and scope of the present invention.

FIGS. 2 to 8 are cross-sectional views illustrating a method of manufacturing a light emitting device according to another embodiment of the present invention.

Referring to FIG. 2, a first conductive base layer 120 is formed on a substrate 110.

The substrate 110 may be a growth substrate. In particular, in this embodiment, the substrate 110 may be a c-plane sapphire substrate or a c-plane nitride substrate.

The first conductive base layer 120 may include a nitride semiconductor such as (Al, Ga, In) N and may be a metal organic chemical vapor deposition (MOCVD), a molecular beam epitaxy (MBE), or a hydride vapor phase epitaxy (HVPE) May be grown on the substrate 110 using techniques such as < RTI ID = 0.0 > Also, the first conductive base layer 120 may be doped n-type, including n-type impurities such as Si.

Alternatively, a buffer layer (not shown) may be formed on the substrate 110 before the first conductive base layer 120 is formed. The buffer layer may serve as a nucleation layer in which semiconductor layers formed in a subsequent process are grown. And may also serve to mitigate the difference in lattice constant. The buffer layer (not shown) may include at least one of a low-temperature buffer layer and a high-temperature buffer layer, and may further include a nitride semiconductor such as AlN or GaN.

The substrate 110 and the first conductive base layer 120 are substantially similar to those described with reference to FIG. 1, and a detailed description thereof will be omitted.

Referring to FIG. 3, a mask layer 130 including a plurality of openings 131 is formed on a first conductive base layer 120.

The mask layer 130 may include at least one of silicon oxide such as SiO ₂ and silicon nitride such as SiN _x, and may be formed using various methods. For example, an insulating material is formed to cover the entire surface of the first conductive base layer 120 using a technique such as electron beam deposition, and a plurality of openings 131 are formed using a photolithography and etching process to form a mask layer 130 may be formed. Alternatively, a mask layer 130 including a plurality of openings 131 may be formed using deposition and lift-off. However, the present invention is not limited thereto.

The plurality of openings 131 of the mask layer 130 may have various shapes and sizes. For example, the plurality of openings 131 may have a circular or polygonal shape, and the diameter or width thereof may be 200 nm to 20 占 퐉, and the spacing distance between the openings may be 500 nm to 50 占 퐉. The formation position and shape of the plurality of light emitting structures 140 to be described later can be determined according to the shape, diameter, or spacing distance of the plurality of openings. Accordingly, the shape, diameter, or spacing of the plurality of openings may be variously selected according to the plurality of light emitting structures 140 to be obtained.

Referring to FIG. 4, a plurality of light emitting structures 140 are formed on a plurality of openings 131.

Each of the light emitting structures 140 may include a first conductive semiconductor layer 141, an active layer 143, and a second conductive semiconductor layer 145, and each semiconductor layer of the light emitting structure 140 may include And a nitride semiconductor such as (Al, Ga, In) N.

The first conductive semiconductor layer 141 may be grown using a technique such as MOCVD (Metal Organic Chemical Vapor Deposition), MBE (Molecular Beam Epitaxy), or HVPE (Hydride Vapor Phase Epitaxy) The semiconductor layer 141 may be grown using the first conductive base layer 120 exposed under the plurality of openings 131 as a seed.

The first conductive semiconductor layer 141 may be grown not only in the vertical direction but also in the horizontal direction, and may be provided using a selective epitaxial growth method or a method using a non-surfactant. The first conductivity type semiconductor layer 141 is grown with horizontal growth so that the first conductivity type semiconductor layer 141 can partially cover the mask layer 130. [ In addition, the first conductivity type semiconductor layer 141 can be grown along the growth plane different from the growth plane of the first conductive base layer 120 by simultaneously growing in the horizontal and vertical directions. 4, the first conductivity type semiconductor layer 141 is formed on the surface 1122 of the {1122} plane of the (1122) plane, as shown in FIG. 4, ). ≪ / RTI > Accordingly, the first conductivity type semiconductor layer 141 may have a semi-polarity, and the first conductivity type semiconductor layer 141 may be grown to have a hexagonal or hexagonal hexagonal shape. However, the present invention is not limited thereto, and the first conductivity type semiconductor layer 141 may be grown along a non-polar or polar surface as well as a semi-polar surface.

The first conductivity type semiconductor layer 141 is grown using MOCVD such that the first conductivity type semiconductor layer 141 is grown with vertical growth and horizontal growth, The directional growth rate and the horizontal growth rate can be selectively controlled.

The active layer 143 may be grown along the growth surface of the first conductivity type semiconductor layer 141 and may be formed to cover the first conductivity type semiconductor layer 141. The second conductive semiconductor layer 145 may also be grown along the growth surface of the active layer 143 and may be formed to cover the active layer 143. Accordingly, the shape of the light emitting structure 140 may be determined depending on the growth surface of the first conductivity type semiconductor layer 141.

The light emitting structure 140 may be formed on the plurality of openings 131 and may be spaced apart from the first conductive semiconductor layer 141, the active layer 143, and the second conductive semiconductor layer 143 It is formed along the growth surface and can have a variety of forms. The light emitting structure 140 may include a tip portion or an end portion, and may have at least one of a hexagonal shape, a truncated hexagonal shape, or a polygonal shape. In addition, the light emitting structure 140 may include inclined side surfaces, and the side surfaces may have an inclination angle of 60 to 65 degrees.

Meanwhile, the contents related to the light emitting structure 140 are substantially similar to those described with reference to FIG. 1, and a detailed description of the overlapping contents will be omitted.

Referring to FIG. 5, a photoresist 210 filling the space between the plurality of light emitting structures 140 is formed. At this time, the tips or end portions of the plurality of light emitting structures 140 are exposed, and in this embodiment, the periphery of the vertex of the hexagonal-shaped light emitting structure 140 is exposed.

The photoresist 210 may be dissolved in an organic solvent, and may include, for example, AZ 5214.

Specifically, for example, the photoresist 210 is formed by applying a photoresist material on the mask layer 130 and the plurality of light emitting structures 140, and then partially etching the plurality of light emitting structures 140 using oxygen plasma 140, respectively. The portion of the partially exposed light emitting structure 140 may be a tip or an end, and in this embodiment the tip may be around the vertex of the hexagon.

Referring to FIG. 6, an insulating material 150a covering the photoresist 210 and the light emitting structure 140 is formed.

Insulating material (150a) it may be formed and may include at least one of silicon nitride and SiN _x, such as a silicon oxide such as SiO _2, is deposited by evaporation using a technique such as electron beam evaporation. At this time, the thickness of the insulating material 150a may be 50 to 300 nm, and may be selectively applied depending on the size of the light emitting device.

Referring to FIG. 7, the photoresist 210 is removed to form the current leakage preventing layer 150. By removing the photoresist 210, the insulating material 150a formed on the photoresist 210 can be partially removed. Accordingly, the insulating material 150a partially remains on the upper portions of the plurality of the light emitting structures 140, so that the current leakage preventing layer 150 can be formed.

The photoresist 210 can be removed by immersing the light emitting device in an organic solvent, for example, acetone.

The description related to the current leakage preventing layer 150 is substantially similar to that described with reference to FIG. 1, and therefore, detailed description thereof will be omitted.

Next, referring to FIG. 8, an insulating layer 160 may be formed on the mask layer 130 on a region between the plurality of light emitting structures 140.

The insulating layer 160 may comprise a transparent polymeric material and may include, for example, photoresist such as SU8 or AZ 5214, or BCB (Benzo Cyclo Butene). However, the present invention is not limited thereto. The insulating layer 160 is formed by coating the transparent polymer material on the mask layer 130 and the plurality of light emitting structures 140 and partially removing the transparent polymer material to form the second conductivity type semiconductor layer 145, As shown in FIG.

1 can be provided by forming the insulating layer 160, the plurality of light emitting structures 140, and the transparent electrode 170 covering the current leakage preventing layer 150. [

The transparent electrode 170 may be formed by depositing a material including ITO (Indium Tin Oxide), ZnO (Zinc Oxide), AZO (Aluminum Zinc Oxide), and IZO (Indium Zinc Oxide), for example. In addition, the transparent electrode 170 may be formed in a shape corresponding to the outer shape of the insulating layer 160 and the light emitting structure 140.

The light emitting device manufacturing method may further include forming a first electrode (not shown) and a second electrode (not shown).

The first electrode may be formed on the partially exposed region of the first conductive base layer 120 by partially removing the materials on the first conductive base layer 120. The second electrode may be formed on a portion of the transparent electrode 170. The first electrode and the second electrode may be formed using a technique such as deposition and lift-off, or may be formed simultaneously or separately in another process. However, the formation positions of the first electrode and the second electrode and the formation process sequence are not limited thereto, and may be variously modified depending on the structure and the form of the light emitting device.

9 is a graph for comparing the voltage-current characteristics of the light emitting device according to the present invention with a comparative example.

The present invention is a light emitting device having a structure as shown in FIG. 1, and the comparative example is a light emitting device which does not include the current leakage preventing layer 150, and the other structure is substantially similar to the present invention.

Referring to FIG. 9A, when the reverse voltage (negative voltage) is applied, the current of the light emitting device of the present invention hardly flows, but the reverse current flows in the comparative example. Therefore, it can be seen that the current leakage of the light emitting device of the present invention is effectively prevented as compared with the light emitting device of the comparative example.

Referring to FIG. 9B, it can be seen that the magnitude of the leakage current is larger in the comparative example than in the present invention, and in particular, when the reverse voltage is applied, the difference is large.

As can be seen from these experiments, the present invention can provide a light emitting device in which the occurrence of leakage current is minimized, and can prevent a decrease in luminous efficiency of the light emitting device.

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 embodiments, but, on the contrary, Variations and changes are possible.

Claims (20)

A first conductive base layer;
A mask layer located on the first conductive base layer and including a plurality of openings;
A plurality of light emitting structures located on the plurality of openings and spaced apart from each other; And
And a leakage current blocking layer partially covering an upper portion of the plurality of light emitting structures. The method according to claim 1,
Wherein each of the plurality of light emitting structures includes a tip portion or an end portion formed on an upper portion thereof,
And the area of the end portion is smaller than the area of the lower surface of the light emitting structure. The method of claim 2,
And the leakage current blocking layer covers the tip portion or the end portion. The method according to claim 2 or 3,
Wherein each of the plurality of light emitting structures is in the form of at least one of a hexagon, a hexagon, a hexagon, and a polyhedron. The method of claim 2,
Wherein each of the plurality of light emitting structures includes an inclined side surface,
Wherein the inclined side face has an inclination angle of 60 to 65 with respect to the upper face of the first conductive base layer. The method according to claim 1,
Wherein the plurality of light emitting structures partially cover the mask layer. The method according to claim 1,
Wherein the leakage current prevention layer comprises at least one of silicon oxide and silicon nitride. The method according to claim 1,
Wherein each of the plurality of light emitting structures comprises:
A first conductive semiconductor layer;
An active layer covering the first conductivity type semiconductor layer; And
And a second conductivity type semiconductor layer covering the active layer. The method of claim 8,
And a transparent electrode covering the plurality of light emitting structures, the leakage current blocking layer, and the mask layer, and electrically contacting the side surfaces of the plurality of light emitting structures. The method of claim 9,
Further comprising an insulating layer interposed between the mask layer and the transparent electrode to fill the space between the plurality of light emitting structures. The method of claim 9,
A region where the upper surface of the first conductive base layer is exposed,
A first electrode located on the exposed region, and
And a second electrode located on the transparent electrode. The method according to claim 1,
The width of the openings is 200 nm to 20 占 퐉, and the spacing between the openings is 500nm to 50 占 퐉. Forming a first conductive base layer on the substrate;
Forming a mask layer including a plurality of openings on the first conductive base layer;
Forming a plurality of spaced apart light emitting structures on the openings; And
And forming a leakage current prevention layer partially covering an upper surface of the plurality of light emitting structures. 14. The method of claim 13,
Each of the plurality of light emitting structures includes a tip portion or an end portion formed on an upper portion thereof, the area of the tip portion or the end portion is smaller than the area of the lower surface of the light emitting structure,
Wherein the plurality of light emitting structures are grown with horizontal growth and vertical growth. 15. The method of claim 14,
The formation of the leakage current prevention layer,
Forming a photoresist that at least partially covers the plurality of light emitting structures and the mask layer, exposing the tip or end;
Forming the photoresist and an insulating material covering the tip or end; And
And removing the photoresist and the insulating material formed on the photoresist. 15. The method of claim 14,
Wherein each of the plurality of light emitting structures is in the form of at least one of a hexagon, a hexagon, a hexagon, and a polyhedron. 15. The method of claim 14,
Wherein each of the plurality of light emitting structures includes an inclined side surface,
Wherein the inclined side surface has an inclination angle of 60 to 65 degrees with respect to an upper surface of the first conductive base layer. 15. The method of claim 14,
The formation of the light-
Growing the first conductive type semiconductor layer by seeding the first conductive type base layer exposed in the opening portion;
Growing an active layer covering the first conductive semiconductor layer; And
And growing a second conductivity type semiconductor layer covering the active layer,
Wherein the first conductivity type semiconductor layer further includes a growth surface different from a growth surface of the first conductivity type base layer. 14. The method of claim 13,
And forming a plurality of light emitting structures, a leakage current blocking layer, and a transparent electrode covering the mask layer. The method of claim 19,
Before forming the transparent electrode,
Further comprising forming an insulating layer partially filled between the plurality of light emitting structures and exposing side surfaces of the plurality of light emitting structures.

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