KR101188279B1 - Nitride Light Emitting Diodes with Sacrificial layer - Google Patents

Abstract

Disclosed is a vertical nitride based light emitting diode including a sacrificial layer in order to block the influence of ultraviolet light applied to the light emitting diode in the process of removing the substrate when manufacturing the vertical nitride based light emitting diode. More specifically, the present invention provides a buffer layer formed on a substrate, an n-side contact layer formed on the buffer layer, and an n-contact layer formed on the n-side contact layer to emit light according to an electrical signal applied to the light emitting diode. A sacrificial layer formed at a predetermined position between the n-side contact layer and the buffer layer to protect the active layer from ultraviolet light used for laser lift-off for the active layer of the quantum well structure and the nitride based light emitting diode. It relates to a vertical nitride light emitting diode.

Description

Vertical nitride based light emitting diodes including a sacrificial layer {Nitride Light Emitting Diodes with Sacrificial layer}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nitride based light emitting diode used in light emitting devices such as light emitting diodes (LEDs), laser diodes (LDs), solar cells, optical sensors, light receiving devices, or electronic devices such as transistors and power devices.

More specifically, the present invention relates to a technique for preventing the effect on the light emitting diode by the laser lift-off process in the manufacture of the vertical light emitting diode.

In general, nitride-based semiconductors have been studied substantially as materials of high luminous blue and pure green LEDs for making light sources of full color LED displays, traffic signals and image scanners. The nitride-based LED device is basically a buffer layer made of GaN on the sapphire substrate, an n-side contact layer made of Si doped GaN, an active layer of a multi-quantum well (MQW) structure containing InGaN or InGaN of a single quantum well (SQW) structure, The p-side contact layer made of Mg-doped GaN has a basic structure formed in this order. This LED device has excellent characteristics at 20 mA at 5 kHz in a light emitting wavelength 450 nm blue LED, 9.1% external quantum efficiency, 3 kHz at 520 nm green LED, and 6.3% external quantum efficiency.

The nitride based light emitting diode may employ a single quantum well having a well layer made of InGaN or a double heterostructure having an active layer of a multi quantum well structure, wherein the multi quantum well structure may include a plurality of mini bands. It is expected to improve the device characteristics such as higher luminous output than a single quantum well structure because of its high efficiency and high light emission.

For example, as an LED device using an active layer of a multi-quantum well structure, Japanese Patent Laid-Open No. 10-135514 discloses a barrier layer made of at least undoped GaN and a well layer made of undoped InGaN in order to improve luminous efficiency and luminous intensity. A nitride based semiconductor device including a light emitting layer having a multi-quantum well structure is disclosed.

In particular, III-V nitride-based light emitting devices have been applied to optical devices including blue / green light emitting diodes (LEDs), and high-speed switching and high-output devices such as MOSFETs and HEMTs. In particular, the light emitting device using the group III nitride semiconductor has a direct transition band gap corresponding to the region from visible light to ultraviolet light, and high efficiency light emission can be realized. Therefore, the semiconductor is mainly used as an LED or a laser diode (LD), and researches for obtaining an easier manufacturing process and higher light efficiency have been continued. Among the III-V nitride semiconductors, gallium nitride (GaN) is typically used, which is grown on a substrate by a crystal growth method, and is activated in a p-type or n-type depending on the doped material, and is composed of a PN junction diode. However, in the present technology, since a single crystal substrate having a lattice structure with which the nitride semiconductor (GaN) can be directly grown cannot be manufactured in large quantities, heterogeneous such as sapphire (Al2O3) single crystal or silicon carbide (SiC) single crystal. Substrates made of materials are mainly used.

In such a nitride-based light emitting diode, there are a structure of a side current injection type light emitting diode in which electrodes are all applied in a front direction, and a vertical structure in which electrodes are formed at upper and lower portions thereof. However, in recent years, vertical light emitting diodes have been preferred to side current injection type LEDs, since the side current injection type LED structure has to be connected to an external power source because all of the unidirectional electrodes need to be connected to an actual product or module. Since the connection means such as bonding must be applied twice, the physical impact for this is applied twice to the corresponding device, the actual light emitting area is reduced for the configuration of the n electrode, and the luminous efficiency due to the poor side current spreading characteristics of the n contact layer. Because it is low. Therefore, in the light emitting diode unit device or a module to which a large number of light emitting diodes are applied, an n electrode or a p electrode is formed on one side of the device itself so that the light emitting diode element can be directly adhered to the electrode of the applied substrate or module. Light emitting diode structures are preferred. In particular, such a vertical light emitting diode device has good efficiency because it has the same device area and active layer size.

Despite the advantages of such vertical light emitting diodes, sapphire single crystals or silicon carbide single crystals cannot be manufactured in large-scale because current techniques cannot produce a large number of single crystal substrates with matching lattice structures enough to directly grow nitride semiconductors (GaN). The nitride semiconductor is epitaxially grown on a substrate made of the same heterogeneous material.

As a result, in order to finally fabricate a vertical nitride based light emitting diode, a substrate removal process must be performed, and multiplexing of the light emitting diodes by ultraviolet rays applied to the light emitting diodes in a substrate removal process by laser lift-off is performed. Optical and structural deterioration occurs in the quantum well structure, which makes it difficult to manufacture high efficiency, high power light emitting diodes.

In view of the above problem, the present invention includes a sacrificial layer for preventing deterioration of a multi-quantum well structure from ultraviolet rays applied to a diode during a laser lift-off process for fabricating a vertical nitride-based W photodiode. It is a technical problem to provide a vertical nitride light emitting device.

To this end, in the present invention, a substrate, an n-side contact layer formed on the substrate, and a multi-quantum well structure formed on the n-side contact layer to emit light according to an electrical signal applied to the light emitting diode. Active layer; And a sacrificial layer formed at a predetermined position between the n-side contact layer and the buffer layer to protect the active layer from ultraviolet light used during laser lift-off to the substrate. to provide.

However, the technical problem of the present invention is not limited to the above-mentioned matters, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above technical problem, a vertical nitride based light emitting diode according to the present invention includes a buffer layer formed on the substrate, an n-side contact layer formed on the buffer layer, and an upper portion of the n-side contact layer. The n side to protect the active layer from an active layer of a quantum well structure that emits light in accordance with an electrical signal applied to the light emitting diode and from ultraviolet rays used for laser lift-off of the light emitting diode. And a sacrificial layer formed at a predetermined location between the contact layer and the buffer layer.

Here, the sacrificial layer preferably has a bandgap energy smaller than the bandgap energy of the buffer layer.

The sacrificial layer may be inserted into at least one layer in the buffer layer and formed to have a predetermined thickness in the buffer layer.

In addition, the active layer is preferably a multi-quantum well structure containing InGaN.

In addition, the sacrificial layer is an n-type impurity-doped In _a Ga _{1 -} is formed by _a N, of which the n-type impurity-doped In _a Ga _{1 -} Composition of the In in _a N is the ultraviolet absorption of the sacrificial layer It is preferably determined in consideration of the intensity, where a is in the range of 0 <a <1.

The n-side contact layer is more preferably an n-GaN layer formed on the substrate by epitaxial growth.

The sacrificial layer may include an In _a Ga _{1 - a} N layer doped with an n-type impurity, and _a phosphate glass or cerium oxide (B) to absorb the ultraviolet rays used for the laser lift-off to protect the active layer. A glass layer formed of phosphate glass to which cerium oxide is added and the sacrificial layer include an In _b Ga _1-b N layer doped with n-type impurities, wherein the In _a Ga _{1 - a} N layer and It is also preferable that the In composition of the In _a Ga _{1 - a} N layer has a different composition. (Where a is 0 <a <1, b is 0 <b <1, but a and b are different values)

On the other hand, in order to achieve the above technical problem, the vertical nitride-based light emitting diode according to the present invention, is formed on the top of the substrate for absorbing the impact of the laser lift-off (laser lift-off) to the substrate A buffer layer, an n-side contact layer formed on the buffer layer, an active layer of a quantum well structure formed on the n-side contact layer to emit light according to an electrical signal applied to the light emitting diode, and an upper portion of the active layer At a predetermined position between the n-side contact layer and the buffer layer to protect the active layer from ultraviolet light used for a p-side contact layer and laser lift-off for the nitride-based light emitting diode formed in the And a sacrificial layer formed.

Here, the sacrificial layer may have a band gap energy smaller than the band gap energy of the buffer layer.

The sacrificial layer may be inserted into at least one layer in the buffer layer, and the sacrificial layer and the buffer layer may be formed to have a predetermined thickness.

Preferably, the active layer is preferably a multi-quantum well structure including InGaN.

In addition, preferably, the sacrificial layer is an n-type impurity-doped In _a Ga _{1 -} is formed by _a N, of which the n-type impurity-doped In _a Ga _{1 -} Composition of the In in _a N is the sacrificial layer is absorbed It may be determined in consideration of the intensity of the ultraviolet rays, wherein a has a range of 0 <a <1.

In addition, the buffer layer may be formed of an undoped GaN layer.

In addition, the sacrificial layer may include an In _a Ga _{1 - a} N layer doped with an n-type impurity, and _a phosphate glass or cerium oxide (B) to absorb the ultraviolet rays used for the laser lift-off to protect the active layer. A glass layer formed of phosphate glass to which cerium oxide is added and the sacrificial layer include an In _b Ga _1-b N layer doped with n-type impurities, wherein the In _a Ga _{1 - a} N layer and It is also preferable that the In composition of the In _a Ga _{1 - a} N layer has a different composition. (Where a is 0 <a <1, b is 0 <b <1, but a and b are different values)

According to the vertical nitride-based light emitting diode according to the present invention from the contents disclosed herein, the effect of the large energy of ultraviolet light used in the laser lift-off process using a high-power ultraviolet laser on the active layer of the multi-quantum well structure It is possible to manufacture high efficiency, high output vertical nitride light emitting diodes by reducing

In addition, the present invention minimizes the structural and optical degradation of the quantum well structure to provide a highly efficient, high-output vertical light emitting diode with high reliability, and thus is not limited to non-single light emitting devices. Applicable to

1 is a view illustrating a conventional vertical nitride based light emitting diode;
2 is a view illustrating a vertical nitride based light emitting diode according to an embodiment of the present invention;
3 is a view illustrating a vertical nitride based light emitting diode according to another embodiment of the present invention;
FIG. 4 illustrates high resolution X-ray diffractometer (HRXRD) spectra and high resolution transmission electron microscopy (HRTEM) images of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention. Degree,
5 is a view showing a PL (PhotoLuminescence) spectra after a laser lift-off process of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention;
6 is a view showing an HRTEM image after a laser lift-off process of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention;
FIG. 7 illustrates a carrier lifetime spectra after a laser lift-off process of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description herein, when a component is described as being connected to another component, this means that the component may be directly connected to another component or an intervening third component may be interposed therebetween. In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. At this time, the configuration and operation of the present invention shown in the drawings and described by it will be described as at least one embodiment, by which the technical spirit of the present invention and its core configuration and operation is not limited.

Prior to the detailed description of the present invention will be described a conventional vertical nitride-based light emitting diode.

1 is a view illustrating a conventional vertical nitride based light emitting diode.

As shown in FIG. 1, a conventional vertical nitride based light emitting diode 10 includes a substrate 11, a u-GaN layer 12, an n-InGaN layer 10, an n-GaN layer 13, and an active layer. 14 and the P-GaN layer 15.

The substrate 11 is provided for a nitride-based light emitting diode that is laminated by epitaxial growth from the substrate 11 when the vertical light emitting diode 10 is manufactured. The substrate 11 is typically a sapphire substrate (Al ₂ O ₃ ). As will be described later, the substrate is opaque and must be finally removed for the fabrication of the vertical light emitting diode 10.

The u-GaN layer 12 is a layer stacked on top of the substrate 11 and formed of GaN undoped with impurities. The u-GaN layer 12 may be referred to as a buffer layer. The u-GaN layer 12 may form an active layer 14 to be described later from ultraviolet rays by laser lift-off in the process of manufacturing the vertical light emitting diode 10. Is prepared to protect. In general, such a buffer layer is formed to have a bandgap energy smaller than that of the active layer. The laser lift-off process is well known as a part of a process for manufacturing a vertical light emitting diode and is briefly described. This process focuses and irradiates excimer laser light onto a substrate used to fabricate a light emitting diode, and thermal energy is concentrated at the interface between the substrate and the u-GaN layer formed on the substrate, so that the interface between the u-GaN layer is gallium and nitrogen molecules. It is a process for separating the substrate instantaneously at the part where the laser light passes while being separated into.

The n-GaN layer 13 is a GaN layer doped with n-type impurities formed on the u-GaN layer 12 and is an n-side contact layer.

The n-GaN layer 13 is stacked on top of the substrate 11 and the substrate 11 to fabricate a vertical light emitting diode, and a buffer layer (u-GaN) provided to block ultraviolet rays generated in the laser lift-off process. After the layer 12 is removed, it is in contact with the cathode electrode to apply an electrical signal to the vertical light emitting diode 10.

The active layer 14 includes alternately stacked InGaN well layers and barrier layers. The well layer referred to herein is a group III nitride semiconductor layer containing In and other Group III elements other than In, and may be made of, for example, InGaN. The barrier layer is made of a gallium nitride based semiconductor, and may be made of, for example, InGaN having an indium composition less than that of the well layer. As the material of the barrier layer, GaN can also be used if necessary. The structure of the active layer 14 may be formed as a single quantum well structure without being limited to the multiple quantum well structure as described above.

The p-GaN layer 15 is a GaN layer doped with p-type impurities and is a p-side contact layer. The p-GaN layer 15 is formed on the active layer 14 and is in contact with the anode electrode although not shown in the drawing. The contact here is preferably an ohmic contact.

 As described above, in the conventional vertical nitride based light emitting diode shown in FIG. 1, the u-GaN layer 12 is used to block ultraviolet rays generated during the substrate removal process by the laser lift-off in the latter part of the process. However, the ultraviolet rays which affect the light emitting diodes during the laser lift-off are KrF ultraviolet lasers having a wavelength of 248 nm, which are very high in energy, causing optical and structural deterioration to occur on the epiwafer of the quantum well structure constituting the active layer 14. (See FIG. 7A).

Hereinafter, a description will be given of the present invention devised to improve the problems of the conventional vertical nitride based light emitting diode.

2 is a view illustrating a vertical nitride based light emitting diode according to an embodiment of the present invention.

As shown in FIG. 2, in one embodiment, the vertical nitride based light emitting diode 20 includes a substrate 21, a buffer layer 22, a sacrificial layer 30, an n-side contact layer 23, and an active layer 24. And a p-side contact layer 25.

The substrate 21 is provided for a nitride based light emitting diode that is formed by epi growth from the substrate 21 when the vertical light emitting diode 20 is manufactured. As the substrate 21, a sapphire substrate (Al ₂ O ₃ ) is typically used. As will be described later, the substrate is opaque, and thus, the substrate must be finally removed to manufacture the vertical light emitting diode 20.

The buffer layer 22 is a layer stacked on the substrate 21 and can be formed of -GaN which is undoped with impurities. The buffer layer 22 primarily protects the active layer 24 to be described later from ultraviolet rays due to laser lift-off in the process of manufacturing the vertical light emitting diode 20. In general, the buffer layer 22 preferably has a bandgap energy smaller than the bandgap energy of the active layer 24.

The sacrificial layer 30 is a layer formed on the buffer layer 22 to block the effect of the ultraviolet light on the light emitting diode 20 by the laser lift-off process described above. That is, the sacrificial layer 30 is a means for secondary protection of the active layer 24. That is, in the above-described laser lift-off process, since the substrate 20 uses a high-energy ultraviolet laser beam, the sacrificial layer (to prevent structural and optical degradation from occurring in the active layer 24 of the quantum well structure to be described later) 30). As the sacrificial layer 30, a material having a band gap energy having a small band gap energy beam of GaN is used. In the present invention, In _a Ga _{1 - a} N is preferably used, where a may change the composition of indium and gallium in the range of 0 <a <1. That is, since InN of the sacrificial layer 30 has a bandgap energy smaller than GaN, the InN absorbs the radiant energy and thermal energy of the ultraviolet laser beam by the laser lift-off process. Therefore, by introducing the sacrificial layer 30 to absorb the ultraviolet rays generated in the laser lift-off process using a high power ultraviolet laser beam (KrF or ArF) to block the effect on the active layer 24.

Alternatively, the sacrificial layer may include an In _a Ga _{1 - a} N layer doped with n-type impurities and _a phosphate glass or cerium oxide to absorb the ultraviolet rays used for the laser lift-off to protect the active layer. A glass layer formed of phosphate glass added with cerium oxide and the sacrificial layer include an In _b Ga _{1 - b} N layer doped with n-type impurities, wherein the In _a Ga _{1 - a} N layer and the in _a Ga _{1 -} composition of _a layer of N in is preferable that each has a different composition. (Where a is 0 <a <1, b is 0 <b <1, but a and b are different values) Cerium exists in two states in glass, Cerium (III) and Cerium (IV) All absorb ultraviolet light strongly. In addition, the phosphate glass has a flexible structure compared to the silicate glass and may contain a large amount of cerium, so in the present invention, phosphate glass or phosphate glass containing cerium is used to sufficiently absorb ultraviolet rays to protect the active layer of the vertical light emitting diode. It is also possible to insert the intercalation between InGaN layers.

The n-side contact layer 23 is a GaN layer doped with n-type impurities formed on the sacrificial layer 30, and is formed of n-GaN in the present invention. The description of the n-side contact layer 23 is replaced with the description of the conventional vertical nitride based light emitting diode.

The active layer 24 is a layer formed on the n-side contact layer 23 described above and includes an InGaN well layer and a barrier layer. The well layer herein is a group III nitride semiconductor layer containing other group III elements except In and In, and may be made of, for example, InGaN. The barrier layer is made of a gallium nitride-based semiconductor, and may be made of, for example, InGaN having an indium composition smaller than that of the well layer. As the material of the barrier layer, GaN can also be used if necessary. The structure of the active layer 24 is not limited to the multiple quantum well structure as described above, of course, may be made of a single quantum well structure.

 The p-side contact layer 25 is a GaN layer doped with p-type impurities and is a p-side contact layer. The p-GaN layer 25 is formed on the active layer 24. Since other descriptions of the p-side contact layer 25 are the same as those described above, the description is omitted here.

Next, as another embodiment of the present invention, an example in which a sacrificial layer of a vertical nitride based light emitting diode is configured differently from one embodiment is described with reference to FIGS. 3 to 3. FIG. 3 to 3 illustrate a vertical nitride based light emitting diode according to another embodiment of the present invention. It demonstrates with reference to the figure shown to make.

As illustrated in FIG. 3, the vertical nitride based light emitting diode 30 according to another embodiment may include a substrate 21, a buffer layer 22, a sacrificial layer 30, an n-side contact layer 23, and an active layer 24. ) And p-side contact layer 25. Here, the descriptions of the substrate 21, the n-side contact layer 23, the active layer 24 and the p-side contact layer 25 are replaced with those described in the embodiment, and the descriptions of the buffer layer 22 and the sacrificial layer 30 are repeated. Only the structure is described.

In another embodiment, a plurality of sacrificial layers 30 are inserted into the buffer layer 22. That is, for example, the buffer layer 22, the sacrificial layer 30, the buffer layer 22, the sacrificial layer 30, and the buffer layer 22 may be formed in a sandwich structure. The number of buffer layers 22 and sacrificial layers 30 to be stacked, the thickness of each layer, and the indium-gallium composition of the sacrificial layer 30 may be selectively changed in consideration of the characteristics of the vertical nitride light emitting diode to be manufactured. have.

Hereinafter, a description will be made of comparing the characteristics of a vertical nitride light emitting diode according to the present invention with a conventional light emitting diode through a drawing.

FIG. 4 illustrates high resolution X-ray diffractometer (HRXRD) spectra and high resolution transmission electron microscopy (HRTEM) images of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention. It is also.

Figure 4 (a) is a HRXRD spectra for the vertical nitride light emitting diode that does not include a sacrificial layer, (b) is an HRXRD spectra for the vertical nitride light emitting diode including a sacrificial layer. Similarly, (c) is an HRTEM image of a vertical nitride light emitting diode that does not include a sacrificial layer, and (b) is an HRTEM image of a vertical nitride light emitting diode including a sacrificial layer.

As shown in (a) and (b) of FIG. 4, the position and intensity of the rotation peak are similar except for the broad peak around 33.9, and the high crystal of the light emitting diode from each individual peak is similar. It can be seen that crystal qualities have been implemented. The sacrificial layer used here was 22 nm thick and formed at a distance of 50 nm from the start of the active layer.

FIG. 5 illustrates a PL (PhotoLuminescence) spectra after a laser lift-off process of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention.

5A and 5B show PL (PhotoLuminescence) spectra after the laser lift-off process of the vertical nitride light emitting diode including the sacrificial layer and the vertical nitride light emitting diode including the sacrificial layer, respectively. As shown, the strength of B was greater than that of A. In addition, as shown in the small box of Fig. 5, the intensity of the yellow emission due to the yellow luminescence band known as a defect level commonly found in GaN is that of the light emitting diode B including the sacrificial layer. In the case of the light emitting diode A, which does not include the sacrificial layer, it is smaller. This is because the sacrificial layer absorbs ultraviolet rays generated during laser lift-off, thereby reducing the defect density of the active layer.

6 is a diagram illustrating an HRTEM image after a laser lift-off process of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention.

Referring to the TEM image shown in FIG. 6, the vertical light emitting diode (a), which did not include the sacrificial layer, formed an indefinite boundary with the laminated structure in which the active layer had a defect compared to the vertical light emitting diode (b) including the sacrificial layer. It can be seen that.

FIG. 7 illustrates a carrier lifetime spectra after a laser lift-off process of a vertical nitride based light emitting diode and a conventional vertical nitride based light emitting diode according to an embodiment of the present invention.

Referring to FIG. 7, the results of the carrier lifetime measurement of the LED according to the presence of the sacrificial layer may be seen. Carrier life is defined as the average time of recombination of excess minority carriers in the active layer. A relatively long carrier life can be interpreted as better light emission efficiency.

A1 and B1 of FIG. 7 are carrier life spectra before the laser lift-off process of the light emitting diode including the sacrificial layer and the light emitting diode not including the sacrificial layer, respectively. Spectra. Carrier life spectra in each of these cases were calculated as time using a fitting program, which was A1-5.6ns, B1-6.2ns, A2-0.3ns, and B2-1.4ns.

This is because the defect density of the active layer after the laser lift-off process is reduced due to the presence of the sacrificial layer, thereby increasing the time required for recombination in the light emitting diode including the sacrificial layer. The luminous efficiency of the fabricated vertical nitride based light emitting diode has more excellent luminous efficiency than the vertical nitride based light emitting diode without sacrificial layer. In summary, vertical nitride based light emitting diodes fabricated with a sacrificial layer have stronger blue-emission intensity and longer carrier life than vertical nitride based light emitting diodes without a sacrificial layer. Have As described above, the sacrificial layer inserted into the vertical light emitting diode has a sacrificial layer protecting the active layer of the quantum well structure from the ultraviolet laser beam generated during the laser leaf-off process for removing the substrate, so that the laser lift-off process is performed. By minimizing the effect on the high-efficiency high-output vertical nitride-based light emitting diodes are possible.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above-described embodiments, which can be variously modified and modified by those skilled in the art to which the present invention pertains. Modifications are possible. Accordingly, it is intended that the scope of the invention be defined solely by the claims appended hereto, and that all equivalents or equivalent variations thereof fall within the spirit and scope of the invention.

11,21 substrate 12,21 u-GaN layer
13,23 n-GaN layer 14,24 active layer
15,25 p-GaN layer 30 sacrificial layer

Claims (14)

In a vertical nitride light emitting diode formed on a substrate,
A buffer layer formed on the substrate;
An n-side contact layer formed on the buffer layer;
An active layer formed on the n-side contact layer to emit light according to an electrical signal applied to the light emitting diode; And
A sacrificial layer formed between the n-side contact layer and the buffer layer to protect the active layer from ultraviolet light used for laser lift-off for the light emitting diode;
And including, the sacrificial layer is an n-type impurity is formed of doped In _a Ga _1-a N, the composition of the n-type impurity-doped In _a Ga In In _1-a N is that the absorption of the sacrificial layer It is determined in consideration of the intensity of the ultraviolet light, wherein a is a vertical nitride-based light emitting diode, characterized in that 0 <a <1. The method of claim 1,
And the sacrificial layer has a band gap energy smaller than the band gap energy of the buffer layer. The method of claim 2,
And the sacrificial layer is inserted into at least one layer in the buffer layer and is formed to have a predetermined thickness in the buffer layer. The method of claim 2,
The active layer is a vertical nitride-based light emitting diode, characterized in that the multi-quantum well structure containing InGaN. delete The method of claim 1,
The sacrificial layer may include an In _a Ga _1-a N layer doped with n-type impurities; And
An In _b Ga _1-b N layer doped with an n-type impurity, wherein the In composition of the In _a Ga _1-a N layer and the In _a Ga _1-a N layer has a different composition. Vertical nitride-based light emitting diode.
(Where a is 0 <a <1, b is 0 <b <1, where a ≠ b) The method of claim 2,
And the n-side contact layer is an n-GaN layer formed by epitaxial growth. In a vertical nitride light emitting diode formed on a substrate,
A buffer layer formed on the substrate to absorb impact caused by laser lift-off on the substrate;
An n-side contact layer formed on the buffer layer;
An active layer formed on the n-side contact layer to emit light according to an electrical signal applied to the light emitting diode;
A p-side contact layer formed on the active layer; And
A sacrificial layer formed between the n-side contact layer and the buffer layer to protect the active layer from ultraviolet light used for laser lift-off for the nitride based light emitting diode;
And including, the sacrificial layer is an n-type impurity is formed of doped In _a Ga _1-a N, the composition of the n-type impurity-doped In _a Ga In In _1-a N is that the absorption of the sacrificial layer It is determined in consideration of the intensity of the ultraviolet light, wherein a is a vertical nitride-based light emitting diode, characterized in that 0 <a <1. 9. The method of claim 8,
And the sacrificial layer has a band gap energy smaller than the band gap energy of the buffer layer. 10. The method of claim 9,
And the sacrificial layer is inserted into at least one layer in the buffer layer, and the sacrificial layer and the buffer layer are formed to have a predetermined thickness. 10. The method of claim 9,
The active layer is a vertical nitride-based light emitting diode, characterized in that the multi-quantum well structure containing InGaN. delete 10. The method of claim 9,
And the buffer layer is formed of an undoped GaN layer. The method of claim 8, wherein
The sacrificial layer may include an In _a Ga _1-a N layer doped with n-type impurities; And
An In _b Ga _1-b N layer doped with an n-type impurity, wherein the In composition of the In _a Ga _1-a N layer and the In _a Ga _1-a N layer has a different composition. Vertical nitride-based light emitting diode.
(Where a is 0 <a <1, b is 0 <b <1, where a ≠ b)

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