KR20120079391A - Nitride-based semiconductor light emitting device and method of manufacturing the same - Google Patents

Abstract

PURPOSE: A nitride-based semiconductor light emitting device and method of manufacturing the same are provided to minimize a total reflection of light by varying a light route coming from an active layer through a p-type nitride layer and a growth preventing film. CONSTITUTION: A n-type nitride layer(130) and active layer(140) are grown on a substrate. A growth preventing film(150) is formed as a previously fixed pattern on the top of the active layer. A p-type nitride layer(160) is formed on the outside of the growth preventing file on the top of the active layer. The p-type nitride layer is formed thicker than the growth preventing film. A transparent electrode layer(170) is included on the top of the growth preventing film and the p-type nitride layer.

Description

Nitride semiconductor light emitting device and its manufacturing method {NITRIDE-BASED SEMICONDUCTOR LIGHT EMITTING DEVICE AND METHOD OF MANUFACTURING THE SAME}

The present invention relates to a semiconductor light emitting device and a method of manufacturing the same. Specifically, the present invention relates to a semiconductor light emitting device having improved light extraction efficiency and a method of manufacturing the same.

The semiconductor light emitting device has various advantages such as long life, low power consumption, excellent initial driving characteristics, and high vibration resistance. Therefore, the demand continues to increase.

The semiconductor light emitting device has a structure in which an n-type nitride layer, an active layer having a quantum well structure, and a p-type nitride layer are sequentially stacked on a substrate. Then, electrons provided in the n-type nitride layer and holes provided in the p-type nitride layer are recombined in the active layer to emit light.

Some of the light generated in the active layer is emitted to the outside through the surface of the light emitting device, the rest is totally reflected at the surface of the light emitting device. The totally reflected light is not emitted to the outside and absorbed by the substrate or the nitride layer of the light emitting device. Therefore, there is a problem of lowering the luminous efficiency of the light emitting device and causing internal heat generation.

The present invention is to provide a semiconductor light emitting device and a method of manufacturing the same that can minimize the total reflection of the light generated on the surface of the light emitting device to solve the above problems.

The above object of the present invention can be achieved by a semiconductor light emitting device including a p-type nitride layer grown to have a predetermined pattern by a growth prevention film and a method of manufacturing the same.

Here, the p-type nitride layer and the growth prevention film are formed above the active layer, and the p-type nitride layer has a thickness thicker than that of the growth prevention film. Therefore, the p-type nitride layer is formed with a hollow structure at the position where the growth prevention film is formed.

On the other hand, the transparent electrode layer is formed on the p-type nitride and the growth prevention film. The transparent electrode layer is in contact with the upper surface of the p-type nitride layer and the inner wall surface of the cavity structure. Therefore, the area where the transparent electrode layer and the p-type nitride layer come into contact with each other is wider than in the related art.

The growth prevention film is formed of a transparent material. For example, a material of SiO ₂ or Si _x N _y (x, y> 0) is used. The growth prevention film is composed of a plurality of dots having a predetermined shape, and may be disposed at regular intervals on the upper surface of the active layer.

On the other hand, the above object of the present invention can also be achieved by a vertical semiconductor light emitting device including a p-type nitride layer grown to have a predetermined pattern by the growth prevention film and a manufacturing method thereof.

Here, the growth prevention film and the p-type nitride layer are formed between the conductive substrate and the active layer. The growth prevention film is formed in a predetermined pattern on the bottom of the active layer. The p-type nitride layer is formed in the portion of the bottom of the active layer where the growth prevention film is not formed.

The p-type nitride layer has a thickness thicker than that of the growth prevention film. Therefore, the p-type nitride layer has a hollow structure formed at the position where the growth prevention film is formed.

On the other hand, a metal layer is formed on the upper surface of the conductive substrate. The metal layer is in contact with the bottom surface of the p-type nitride layer and the inner wall surface of the cavity structure. Therefore, the area where the metal layer and the p-type nitride layer come into contact with each other is wider than in the related art.

According to the present invention, the growth prevention film and the p-type nitride layer diversify the path of light irradiated from the active layer. Thus, light extraction efficiency is improved by minimizing total reflection of light on the surface of the light emitting device.

1 is a perspective view of a nitride semiconductor light emitting device according to a first embodiment of the present invention;
2 is a cross-sectional view of the nitride semiconductor light emitting device of FIG.
3 is a plan view of the nitride semiconductor light emitting device of FIG.
4 is a flowchart illustrating a method of manufacturing the nitride semiconductor light emitting device of FIG. 1;
5 is a schematic diagram schematically showing the sequence of the manufacturing method of FIG.
6 is a cross-sectional view of a vertical nitride semiconductor light emitting device according to a second embodiment of the present invention;
FIG. 7 is a schematic diagram schematically illustrating a procedure of a method of manufacturing the vertical nitride semiconductor light emitting device of FIG. 6.

Hereinafter, with reference to the accompanying drawings will be described in detail a first preferred embodiment of the present invention. However, in describing the positional relationship of each component, the formulas such as 'top', 'bottom', 'top', 'bottom', etc. are used when each component is in direct contact with each other and Includes all indirectly intervened. In addition, the positional relationship of each component is demonstrated based on drawing. The size of the components shown in the drawings may be exaggerated for description, it does not mean that the actual size is noted above.

1 is a perspective view of a semiconductor light emitting device according to a first embodiment of the present invention. 2 is a cross-sectional view of the semiconductor light emitting device, and FIG. 3 is a plan view of the semiconductor light emitting device.

As shown in FIG. 1 and FIG. 2, the nitride semiconductor light emitting device according to the present exemplary embodiment includes a substrate 110 and a buffer layer 120, an n-type nitride layer 130, and the like, which are sequentially stacked on the substrate. The active layer 140 is included. A plurality of growth prevention layers 150 are provided in a predetermined pattern on the upper side of the active layer 140, and the p-type nitride layer 160 is formed in a portion where the growth prevention layer 150 is not formed. The transparent electrode 170 is formed above the growth prevention film 150 and the p-type nitride layer 160.

Specifically, the substrate 110 is made of a material capable of lattice growing a nitride layer on the upper surface. In this embodiment, a sapphire (Al ₂ O ₃ ) substrate 110 having a hexagonal crystal system such as a nitride layer is used. In addition, substrates such as silicon carbide (SiC), silicon (Si), zinc oxide (ZnO), gallium arsenide (Ga), gallium nitride (GaN), sapphire (Al ₂ O ₃ ), spinel (MgAlO ₄ ), and the like may be used. It may be.

The buffer layer 120 is formed between the sapphire substrate 110 and the n-type nitride layer 130. In addition, the gap between the sapphire substrate 110 and the n-type nitride layer 130 serves as a buffer to improve the lattice matching between the substrate 110 and the n-type nitride layer 130. The buffer layer 120 is made of nitride of AlN or GaN which is undopped.

In FIG. 1 and FIG. 2, the buffer layer 120 is illustrated as one layer, but may be configured as a plurality of layers. For example, a plurality of buffer layers 120 having different characteristics may be configured by different growth temperatures. Alternatively, a plurality of buffer layers 120 having different materials may be configured by different process gases supplied during growth.

The n-type nitride layer 130 is located above the buffer layer 120. The n-type nitride layer 130 is composed of a nitride layer of GaN or AlGaN doped with an n-type dopant. The n-type nitride layer 130 is electrically connected to the n-side electrode pad 182. In addition, when a current is applied to the n-side electrode pad 182, the n-type nitride layer 130 provides electrons to the active layer 140.

In this embodiment, silicon (Si) is used as the n-type dopant. In addition, germanium (Ge), tin (Sn), or the like can be used.

The p-type nitride layer 160 is composed of a nitride layer of GaN or AlGaN doped with a p-type dopant. The p-type nitride layer 160 is electrically connected to the p-side electrode pad 181 through a transparent electrode (not shown). When a current is applied to the p-side electrode pad 181, the p-type nitride layer 160 provides holes to the active layer 140.

In the present embodiment, magnesium (Mg) is used as the p-type dopant, and zinc (Zn) or beryllium (Be) may be used in addition to this.

Meanwhile, the active layer 140 is formed between the n-type nitride layer 130 and the p-type nitride layer 160. Here, the active layer 140 is a quantum barrier layer (not shown) and the quantum well layer (not shown) are alternately stacked to form a multi-well structure or a single well structure.

The quantum well layer is a ternary or quaternary nitride in the form of Al _x In _y Ga _{1 -x- y} N (0 = x <1, 0 <y <1, x + y = 1) to emit light in the visible region. It is composed of layers. The quantum barrier layer is formed of a nitride layer of GaN, AlInGaN or InGaN, and has a larger energy band gap than the quantum well layer.

When a current is applied to the nitride semiconductor light emitting device, electrons and holes are provided as active layers from the n-type nitride layer 130 and the p-type nitride layer 160, respectively. Electrons and holes pass through the quantum barrier layer in the active layer 140 and are disposed in each quantum well layer. In addition, electrons and holes are recombined in the quantum well layer, and irradiate light having a wavelength corresponding to an energy band gap of the quantum well layer.

Some of the light irradiated upward from the active layer passes through the surface of the light emitting device p-type nitride layer and is emitted to the outside. The remainder is totally reflected on the surface of the p-type nitride layer and absorbed into the light emitting device. Therefore, the luminous efficiency of the light emitting device is lowered, which may cause internal heat generation of the light emitting device.

Therefore, the p-type nitride layer 160 according to the present invention is formed in a three-dimensional structure having a predetermined pattern. As an example, the p-type nitride layer may be formed in a plurality of columnar shapes arranged in a predetermined pattern. As another example, the p-type nitride layer may be configured to have a hollow structure of a predetermined pattern inside. In addition to this, the p-type nitride layer 160 can be configured in various shapes.

In this case, the p-type nitride layer 160 has a surface formed in various directions as compared with the conventional flat plate structure. Therefore, the phenomenon that the light irradiated from the active layer 140 is totally reflected on the surface of the p-type nitride layer 160 can be minimized.

In detail, a plurality of growth prevention layers 150 are provided in a predetermined pattern on the upper side of the active layer 140. The p-type nitride layer 160 is not grown on the portion where the growth barrier layer 150 is formed, but is grown on the portion where the growth barrier layer 150 is not formed on the upper side of the active layer 140.

As shown in FIG. 2, the p-type nitride layer 160 has a thickness thicker than that of the growth prevention film 150 and is grown high in the vertical direction. Accordingly, the p-type nitride layer 160 is formed to surround the side surface of the growth prevention film 150. The p-type nitride layer 160 does not grow above the growth barrier 150, and a plurality of hollow structures H are formed.

As such, the p-type nitride layer 160 includes a plurality of hollow structures H therein by the growth prevention film. Therefore, the light irradiated from the active layer 140 is emitted to the outside not only through the upper surface of the p-type nitride layer 160 but also through the inner wall surface of the hollow H.

Here, the cavity structure of the p-type nitride layer can be formed by directly etching the p-type nitride layer without using the growth prevention film. However, the p-type nitride layer has a large atomic radius of the p-type dopant and a strong bonding property with hydrogen, so that the lattice structure is relatively unstable. Therefore, the p-type nitride layer is easily degraded in crystal quality by a post-process, such as etching, thereby reducing the density of holes (holes).

In contrast, the present invention selectively limits the position where the p-type nitride layer 160 is grown by the growth preventing film 150 to form a plurality of cavity structures (H). Therefore, in the present invention, there is no fear of lowering the crystal quality of the p-type nitride layer 160.

Meanwhile, as shown in FIG. 3, the growth preventing film 150 according to the present embodiment is formed of a plurality of circular dots. Each circular dot is arranged at regular intervals.

However, this is only one example, and the present invention is not limited thereto. In addition to this, the growth prevention film may be composed of dots of various shapes such as square or hexagon. Alternatively, the present invention may be configured in a plurality of band shapes instead of dots.

On the other hand, the growth barrier 150 is formed of a transparent material. Therefore, the light irradiated to the portion where the growth prevention film 150 is formed is emitted to the outside through the growth prevention film 150. Alternatively, the growth barrier 150 and the p-type nitride layer 160 may be sequentially passed through and discharged to the outside.

The growth preventing film 150 is made of a silicon oxide such as SiO ₂ or a silicon nitride made of Si _x N _y (x, y> 0). The material of the growth preventing film 150 has a refractive index different from that of the adjacent active layer 140 and the p-type nitride layer 160. Therefore, the light radiated from the active layer 140 passes through the growth preventing layer 150, and thus, the propagation path is diversified, thereby improving light extraction efficiency of the light emitting device.

On the other hand, the transparent electrode 170 is formed above the growth prevention film 150 and the p-type nitride layer 160. The transparent electrode 170 is in ohmic contact with the p-type nitride layer 160. The p-side electrode pad 181 is provided on the transparent electrode 180. Therefore, the transparent electrode 180 diffuses the current provided from the p-side electrode pad 181 to the p-type nitride layer 160.

The transparent electrode 170 is formed to include a metal material such as nickel (Ni) or silver (Au). Or, it is formed of a conductive oxide material having excellent light transmittance, such as indium tin oxide (ITO).

As shown in FIG. 2, the transparent electrode 180 is deposited on the p-type nitride layer 160 and the growth prevention layer 150. Therefore, the plurality of hollow structures H included in the p-type nitride layer 160 are filled by the transparent electrode 180. Accordingly, the transparent electrode 180 forms a contact surface with the p-type nitride layer 160 on the upper surface of the p-type nitride layer 160 and the inner wall surface of the cavity structure H.

As a result, the area of the contact surface of the p-type nitride layer 160 and the transparent electrode 180 increases. Therefore, the current flowing into the transparent electrode 180 may be evenly spread to the p-type nitride layer 160.

Meanwhile, as described above, the p-side electrode pad 181 is provided above the transparent electrode 170, and the n-side electrode pad 182 is provided in the n-type nitride layer 130.

FIG. 4 is a flowchart illustrating a method of manufacturing the nitride semiconductor light emitting device of FIG. 1, and FIG. 5 is a schematic diagram schematically illustrating the procedure of the manufacturing method of FIG. 4. Hereinafter, a method of manufacturing the nitride semiconductor light emitting device according to the first embodiment will be described with reference to FIGS. 4 and 5.

First, the sapphire substrate 110 is introduced into a metal organic chemical vapor deposition (MOCVD) apparatus. Hydrogen (H ₂ ) is supplied into the MOCVD apparatus. Then, the substrate is cleaned by heat treatment for a predetermined time by driving the heater of the MOCVD apparatus (S10).

Thereafter, a process gas is supplied onto the substrate 110 to form the buffer layer 120 (S20). In the present embodiment, trimethyl gallium (TMGa) and ammonia (NH ₃ ) are supplied to form a buffer layer 130 made of GaN. After the buffer layer 130 is grown to a thickness of 30 to 50 μm at a temperature of 500 to 600 ° C., the buffer layer 130 may be further grown by a thickness of 1 to 3 μm by increasing the temperature to 1000 ° C. or more.

When the growth of the buffer layer 130 is completed, the n-type nitride layer 140 is grown (S30). In this case, while growing a GaN layer by supplying trimethyl gallium (TMGa) and ammonia (NH ₃ ) in a hydrogen atmosphere, a silane (silane, SiH ₄ ) gas is supplied to dope silicon (Si) in the GaN layer. This process is performed at a temperature of 1000 ~ 1200 ℃, to grow the n-type nitride layer 140 to a thickness of 3 ~ 5㎛.

Above the n-type nitride layer 140, an active layer 150 including a plurality of quantum barrier layers and a plurality of quantum well layers is grown (S40). The quantum barrier layer is grown into a GaN layer in an environment supplied with trimethyl gallium (TMGa) and ammonia (NH ₃ ). The quantum well layer is grown to an InGaN layer in an environment in which trimethyl gallium (TMGa), trimethyl indium (TMIn), and ammonia (NH ₃ ) are supplied. The quantum barrier layer and the quantum well layer are alternately stacked to form a multi-well structure.

When the growth of the active layer 140 is finished, the growth prevention film 150 is deposited on the active layer 140 (S50). The growth prevention layer 150 is deposited in a predetermined pattern through a photo lithography process.

Specifically, a photoresist R is applied on the active layer 140. Then, the exposure process is performed using the mask M on which the pattern is formed (see a in FIG. 5).

A portion of the photoresist R modified by the exposure process is removed to form a pattern (see FIG. 5B).

Then, the substrate 110 is introduced into a plasma enhanced chemical vapor deposition (PECVD) apparatus. The plasma reaction is induced by supplying silane (SiH ₄ ) gas and oxygen (O ₂ ) to the PECVD apparatus. As a result, SiO ₂ is deposited on the active layer 140 and the photoresist R of the substrate 110 (see FIG. 5C).

Thereafter, an etching process is performed to remove the photoresist R remaining on the active layer 140 and the SiO ₂ grown on the photoresist R. As a result, a plurality of growth preventing films 150 formed in a predetermined pattern are formed on the active layer 140 (see FIG. 5D).

When the growth prevention film 150 is formed, the substrate 110 is moved back to the MOCVD apparatus. Then, the p-type nitride layer 160 is grown on the active layer 140 (S60). The p-type nitride layer 160 is grown into a GaN layer by supplying trimethyl gallium (TMGa) and ammonia (NH ₃ ) in a hydrogen atmosphere, and magnesium (Mg) is doped by supplying a small amount of Cp ₂ Mg (bis magnesium). .

Here, the p-type nitride layer 160 is grown at the portion where the growth preventing film 150 is not formed on the active layer 140. The p-type nitride layer 160 is not grown in the portion where the growth prevention film 150 is formed (see e of FIG. 5).

However, under low pressure or high temperature, epitaxial lateral over growth (ELOG) of the p-type nitride layer may be performed. In this case, the p-type nitride layer is grown while covering the upper surface of the growth prevention film, so that no cavity structure is formed.

Therefore, in this embodiment, the MOCVD apparatus is controlled such that the growth environment of the p-type nitride layer maintains a pressure of 40 to 80 Torr and a temperature of 950 to 1050 ° C. As a result, the p-type nitride layer 160 grows in the vertical direction to form a plurality of cavity structures (H).

The p-type nitride layer 160 is grown thicker than the thickness of the growth barrier 150 and is grown to a thickness of 10 ~ 500nm.

When the growth of the p-type nitride layer 160 is completed, the transparent electrode 170 is deposited on the p-type nitride layer (S70). The transparent electrode 170 according to the present embodiment is made of an indium tin oxide (ITO) material, and is deposited by a sputtering method or an E-beam deposition method. As a result, the transparent electrode 170 is deposited to cover the upper surface of the p-type nitride layer 160 and the growth prevention film 150 (see FIG. 5F). In this case, the hollow structure H formed on the growth prevention layer 150 is also filled by the transparent electrode 170.

When the transparent electrode 170 is formed, the n-side electrode pad 182 and the p-side electrode pad 181 are provided (S80), respectively, to manufacture a nitride semiconductor light emitting device (see FIG. 5G).

Hereinafter, a nitride semiconductor light emitting device according to a second embodiment of the present invention will be described. In the above embodiment, the horizontal semiconductor light emitting device has been described. On the contrary, in the present embodiment, the vertical nitride semiconductor light emitting device to which the present invention is applied will be described. However, in order to avoid duplication of description, a description of the configuration and method similar to the above-described embodiment will be omitted.

6 is a cross-sectional view of a vertical nitride semiconductor light emitting device according to a second embodiment of the present invention.

As shown in FIG. 6, in the vertical nitride semiconductor light emitting device according to the present embodiment, a conductive substrate 280 is provided on a bottom surface thereof. The p-type nitride layer 260, the active layer 240, and the n-type nitride layer 230 are sequentially stacked on the conductive substrate 280. An upper side of the n-type nitride layer 230 is provided with a transparent electrode and an n-side electrode pad 290.

On the bottom of the active layer 240, a growth prevention film 250 is provided in a predetermined pattern. The growth prevention film limits a region in which the p-type nitride layer 260 is grown. Accordingly, the p-type nitride layer 260 is formed at a portion of the bottom surface of the active layer 240 where the growth prevention film 250 is not formed.

Here, the p-type nitride layer 260 has a thickness thicker than the growth prevention film 250. Therefore, a plurality of hollow structures are formed below each growth preventing film 250. Since this configuration has been described in detail in the above-described first embodiment, a detailed description thereof will be omitted.

The conductive substrate 280 is provided below the p-type nitride layer 260. The conductive substrate 280 may use a silicon (Si), germanium (Ge), GaAs, GaP, or GaN substrate doped with impurities. Or it is also possible to use metal substrates, such as aluminum (Al), zinc (Zn), silver (Ag), or these alloy substrates.

The metal layer 270 is formed between the conductive substrate 280 and the p-type nitride layer 260. The metal layer 270 is made of a material having excellent conductivity. Therefore, the current supplied from the conductive substrate 280 flows into the p-type nitride layer 260 through the metal layer 270.

On the other hand, although not shown in the drawings, such a metal layer may be composed of a structure in which a metal reflective layer and a metal adhesive layer are stacked.

The metal reflective layer is coated on the lower surface of the p-type nitride layer 260 and the growth preventing film 250 and the inner wall surface of the cavity structure H. Here, the metal reflective layer is made of a material having excellent reflectance such as silver (Ag) or aluminum (Al). Therefore, the light irradiated downward from the active layer 240 is reflected by the metal reflective layer is emitted through the upper surface of the light emitting device.

The metal adhesive layer is formed on the upper surface of the conductive substrate 280. The conductive substrate 280 is attached to the lower surface of the p-type nitride layer 260 by a metal adhesive layer.

The metal adhesive layer is made of an alloy material used for flip chip bonding. These alloys have a low melting point of 200-300 ° C. and have adhesion at low temperatures. Specifically, the metal adhesive layer is made of a material containing at least one of Au-Sn, Sn, In, Au-Ag, Pb-Sn.

As such, the metal layer 270 of the present embodiment is divided into a metal reflective layer and a metal adhesive layer. However, it is also possible to construct the metal adhesive layer from a material having excellent reflectance without providing a metal reflective layer separately.

The metal layer 270 is formed between the p-type nitride layer 260 and the conductive substrate 280. Then, the inside of the hollow structure H formed under the growth prevention film 250 is filled. Therefore, the metal layer 270 forms a contact surface not only on the lower surface of the p-type nitride layer 260 but also on the inner wall surface of the cavity structure H and the lower surface of the growth prevention film 250.

In the vertical semiconductor light emitting device according to the present embodiment, when light is irradiated downwardly from the active layer 240, the vertical semiconductor light emitting device is upwardly reflected by the metal layer 270 and is emitted. In this case, the reflective surface of the metal layer 270 has a pattern of an uneven structure by the plurality of cavity structures (H). Therefore, the present invention improves light extraction efficiency by diffusely reflecting light by the reflecting surface having an uneven structure.

In addition, the growth prevention layer 250 has a refractive index different from that of the adjacent p-type nitride layer 260. Therefore, the light radiated from the active layer 240 passes through the growth prevention layer 250 and the path of the light is diversified, thereby improving light extraction efficiency.

Furthermore, as described above, the present invention has a larger area where the metal layer 270 and the p-type nitride layer 260 contact each other than in the related art. As such, since the area where the p-type nitride layer 260 is energized with the metal layer 270 is widened, current flows evenly into the p-type nitride layer 260.

7 is a schematic diagram schematically illustrating a method of manufacturing the light emitting device according to FIG. 6. Hereinafter, a method of manufacturing the nitride semiconductor light emitting device according to the second embodiment will be described in detail with reference to FIG. 7.

First, a buffer layer 220, an n-type nitride layer 230, and an active layer 240 are grown on a growth substrate 210. In addition, the growth prevention layer 250 is formed on the active layer 240 in a predetermined pattern. Then, the p-type nitride layer 260 is grown to a portion where the growth prevention film 250 is not formed. Since the description of this process has been described in detail in the first embodiment, it will be omitted (refer to a of FIG. 7).

Then, the conductive substrate 280 is attached to the p-type nitride layer 260 (see b of FIG. 7). The conductive substrate 280 uses a silicon (Si) substrate doped with impurities, but may use a substrate of another material.

At this time, the conductive substrate 280 is attached to the p-type nitride layer 260 by the adhesive metal layer 270. For example, the metal layer 270 may be coated on the conductive substrate 280, and the conductive substrate 280 may be attached to the p-type nitride layer 260. Alternatively, after applying the metal layer 270 to the p-type nitride layer 260, the conductive substrate 280 may be attached to the p-type nitride layer 260.

Accordingly, the contact surface of the p-type nitride layer 260 and the metal layer 270 forms a reflective surface. Since the metal layer 270 is filled into the cavity structure H, the inner wall surface of the cavity structure H and the top surface of the growth prevention film 250 also form reflective surfaces (see FIG. 6).

However, when the metal layer 270 is made of a material having a poor reflectance, the reflective surface may be coated with a material of silver (Ag) or aluminum (Al) before attaching the conductive substrate 280.

On the other hand, when the conductive substrate 280 is attached, the growth substrate 210 is removed. This step is performed by a laser lift off method of irradiating a laser to the buffer layer 220 to separate the growth substrate 210 (see FIG. 7C).

When the growth substrate 210 is separated from the buffer layer 220, the buffer layer 220 is etched to expose the n-type nitride layer 230. Then, a transparent electrode is formed on the exposed n-type nitride layer 230, and an n-side electrode pad 290 is provided to complete the vertical nitride semiconductor light emitting device (see FIG. 6).

As such, in the nitride semiconductor light emitting device according to the present embodiment, light extraction efficiency is improved by pattern-growing the p-type nitride layer 260. In addition, since the area into which the current flows into the p-type nitride layer 260 also increases, the luminous efficiency of the active layer 240 is improved.

In the above, the present invention has been described with reference to two examples. However, the present invention is not limited thereto, and various modifications and applications may be made by those skilled in the art without departing from the essential characteristics of the present embodiment.

110 substrate 120 buffer layer
130: n-type nitride layer 140: active layer
150: growth prevention film 160: p-type nitride layer
170: transparent electrode

Claims (20)

An n-type nitride and an active layer grown on the substrate;
A growth prevention layer formed in a predetermined pattern on the active layer;
A p-type nitride layer formed on a portion of the active layer other than the growth prevention film; And,
A nitride semiconductor light emitting device comprising the growth prevention layer and a transparent electrode layer provided on the p-type nitride layer. The method of claim 1,
The p-type nitride layer is formed thicker than the growth prevention film nitride semiconductor light emitting device. The method of claim 2,
The p-type nitride layer surrounds a side surface of the growth prevention film, and has a hollow structure above the growth prevention film. The method of claim 3,
And the transparent electrode layer forms a contact surface with an upper surface of the p-type nitride layer and an inner wall surface of the hollow structure. The method of claim 1,
The growth preventing film is a nitride semiconductor light emitting device, characterized in that formed of a transparent material. The method of claim 5,
The growth preventing film is a nitride semiconductor light emitting device, characterized in that consisting of SiO ₂ or Si _x N _y (x, y> 0). The method of claim 1,
The growth prevention film is composed of a plurality of dots (dot) having a predetermined shape, characterized in that formed on the upper side of the active layer nitride semiconductor light emitting device. Conductive substrates; And
It includes a p-type nitride layer, an active layer and an n-type nitride layer provided sequentially on the conductive substrate,
And a growth prevention film formed in a predetermined pattern on a bottom surface of the active layer, and the p-type nitride layer is provided on a bottom surface of the active layer in which the growth prevention film is not formed. The method of claim 8,
The p-type nitride layer is formed to surround the side of the growth prevention film, and formed thicker than the growth prevention film, the vertical nitride semiconductor light emitting device, characterized in that it has a hollow structure below the growth prevention film . The method of claim 8,
The growth preventing film is a vertical nitride semiconductor light emitting device, characterized in that formed of a transparent material. The method of claim 8,
The growth preventing film is composed of a plurality of dots (dot) having a predetermined shape, characterized in that formed on the lower surface of the active layer vertical nitride semiconductor light emitting device. The method of claim 10,
A metal layer having excellent reflectance is formed on the conductive substrate, and the metal layer forms a contact surface with a lower surface of the p-type nitride layer and an inner wall surface of the pore structure. Growing an n-type nitride layer and an active layer over the substrate;
Forming a growth prevention film in a predetermined pattern on the active layer;
Growing a p-type nitride layer over the active layer; And
Depositing a transparent electrode layer on top of the p-type nitride layer,
And the p-type nitride layer is grown at a position where a growth prevention film is not formed on the upper side of the active layer. The method of claim 13,
And the p-type nitride layer is grown thicker than the thickness of the growth prevention film. The method of claim 13,
The p-type nitride layer may be grown by growing the p-type nitride layer such that a hollow structure is formed above the growth barrier layer.
The depositing of the transparent electrode layer may include depositing the transparent electrode layer to form a contact surface with an upper surface of the p-type nitride layer and an inner wall surface of the cavity structure. The method of claim 13, wherein the forming of the growth barrier layer is performed.
Applying a photoresist on top of the active layer;
Exposing the photoresist to form a predetermined pattern; And
And depositing the growth preventing film so as to correspond to the pattern formed in the photoresist. The method of claim 13,
The growth preventing film is a method of manufacturing a nitride semiconductor light emitting device, characterized in that consisting of SiO ₂ or Si _x N _y (x, y> 0). Growing an n-type nitride layer and an active layer on a growth substrate;
Forming a growth prevention film in a predetermined pattern on the active layer;
Growing a p-type nitride layer on a portion of the upper side of the active layer other than the growth prevention film;
Providing a conductive substrate above the p-type nitride layer; And
Removing the growth substrate and forming an electrode pad; and manufacturing a vertical nitride semiconductor light emitting device. 19. The method of claim 18,
In the growing of the p-type nitride layer, the p-type nitride layer is grown thicker than the growth prevention layer so that a hollow structure is formed above the growth prevention layer. Manufacturing method. 20. The method of claim 19,
Forming a metal layer between the conductive substrate and the p-type nitride layer;
The forming of the metal layer may include filling the metal layer into the hollow structure to form a contact surface between the inner wall surface of the cavity structure and the metal layer. .

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