Light emitting device

Abstract

Disclosed in embodiments of the present application are a light emitting device, a light emitting device package, and a light emitting module having the light emitting device package. According to embodiments, the light emitting device has a first superlattice layer disposed on an AlN template layer, and a first semiconductor layer, a second superlattice layer, and a first conductive semiconductor layer; an active layer having a quantum well layer and a quantum barrier layer disposed on the first conductive semiconductor layer; an electron blocking layer disposed on the active layer, and a second conductive semiconductor layer. The second of the first and second layers of the first superlattice layer, the first semiconductor layer, and the third and fourth layers of the second superlattice layer comprise AlGaN-based semiconductors, the aluminum composition of the third layer is higher than that of the fourth layer, and has the same composition range as that of the first semiconductor layer. The active layer emits ultraviolet light.

Description

[0001] This application is a divisional application of the invention patent application filed on April 14, 2017, with international application number PCT / KR2017 / 004065 and Chinese national phase application number 201780023885.9, entitled "Light-emitting device, light-emitting device package and light-emitting module".

[0002] Cross-reference to related applications

[0003] This application claims priority to Korean Patent Application No. 10-2016-0046356, filed in Korea on April 15, 2016, and Korean Patent Application No. 10-2016-0049327, filed in Korea on April 22, 2016, the entire contents of which are incorporated herein by reference. Technical Field

[0004] The embodiments relate to light-emitting devices that emit ultraviolet light.

[0005] The embodiments relate to light-emitting device packages and light-emitting modules having light-emitting devices that emit ultraviolet light.

[0006] The embodiments relate to medical devices with ultraviolet light-emitting devices. Background Technology

[0007] A light-emitting diode (LED) is a light-emitting device that emits light when an electric current is applied. LEDs can emit light efficiently at low voltages, thus exhibiting excellent energy-saving performance.

[0008] Due to their high thermal stability and wide bandgap energy, nitride semiconductors have attracted great attention in the development of optical devices and high-power electronic devices. In particular, ultraviolet (UV) LEDs, blue LEDs, green LEDs, and red LEDs using nitride semiconductors have been commercialized and are widely used.

[0009] Ultraviolet (UV) LEDs are light-emitting devices that emit light with wavelengths ranging from 200 to 400 nm. Depending on the application, UV LEDs consist of short and long wavelengths. Short wavelengths are used for sterilization or purification, while long wavelengths can be used in exposure or curing equipment. In particular, UVB, with wavelengths ranging from 280 to 315 nm, can be used in medical applications.

[0010] Recently, UV LEDs for precision medical devices and the like require target wavelengths in the 280nm to 315nm range and high-efficiency UV LEDs capable of high-current driving. Furthermore, light-emitting modules for medical devices need UV LEDs that can reduce the number of light-emitting devices, achieve 70% or higher light uniformity, and realize therapeutic wavelength bands. Summary of the Invention

[0011] Technical issues

[0012] Examples may provide ultraviolet light-emitting devices capable of high-current driving, such as hundreds of mA or higher.

[0013] Examples of this invention can provide ultraviolet light-emitting devices capable of achieving high current and UVB light.

[0014] Examples may provide ultraviolet light-emitting devices that can improve defects.

[0015] Examples of this invention can provide ultraviolet light-emitting devices that can improve luminous efficiency.

[0016] The embodiment can provide an ultraviolet light-emitting device that can improve optical power.

[0017] Examples may provide an ultraviolet light-emitting device having a full width at half maximum (FWHM) of 17 nm or less and emitting UVB rays from 295 nm to 315 nm, as well as a light-emitting device package having the ultraviolet light-emitting device. Examples may provide ultraviolet light-emitting devices that can improve reliability and methods for manufacturing the same.

[0018] Examples may provide a light-emitting device package and a light-emitting device with an ultraviolet light-emitting device.

[0019] Examples may provide light-emitting modules and medical devices capable of improving the uniformity of light in a target area.

[0020] Examples of this invention may provide light-emitting modules and medical devices that can improve the reliability of ultraviolet wavelengths with a full width at half maximum (FWHM) of 17 nm or less for medical processing.

[0021] Examples may provide a light-emitting module and a medical device that can achieve UVB of 300 to 320 nm (driven by a high current of 200 mA or higher), have a full width at half maximum (FWHM) of 17 nm or less, and have light uniformity of 70% or higher.

[0022] Technical solution

[0023] The light-emitting device according to an embodiment includes: an AlN template layer; a first superlattice layer disposed on the AlN template layer; a second superlattice layer disposed on the first superlattice layer; a first semiconductor layer disposed between the first and second superlattice layers; a first conductivity type semiconductor layer disposed on the second superlattice layer; an active layer disposed on the first conductivity type semiconductor layer and having a quantum well layer and a quantum wall layer; an electron blocking layer disposed on the active layer; and a second conductivity type semiconductor layer disposed on the electron blocking layer, wherein the first superlattice layer includes a first layer having an AlN semiconductor and a second layer having an AlGaN-based semiconductor. The first semiconductor layer comprises an AlGaN-based semiconductor, the second superlattice layer comprises a third layer having an AlGaN-based semiconductor and a fourth layer having an AlGaN-based semiconductor, the first and second layers are alternately disposed in the first superlattice layer, the third and fourth layers are alternately disposed in the second superlattice layer, the aluminum (Al) component in the compound formulas of the first semiconductor layer, the second layer and the third layer is a gallium (Ga) component or more and the difference in the composition ratio of the aluminum (Al) component to the gallium component is 10% or less, the thickness of the first semiconductor layer is greater than the thickness of the first superlattice layer having a single pair of first and second layers, and the active layer emits ultraviolet light.

[0024] The ultraviolet light-emitting device according to an embodiment includes: a substrate; an AlN template disposed on the substrate; a first superlattice layer disposed on the AlN template; a second superlattice layer disposed on the first superlattice layer; and a first conductivity type first semiconductor layer disposed between the first and second superlattice layers, wherein the first conductivity type first semiconductor layer includes an Al component and overlaps with the first and second superlattice layers, thereby improving defects, increasing luminous efficiency, optical power and reliability, and achieving high current-driven UVB at 295 to 315 nm.

[0025] According to an embodiment, the aluminum content of the first semiconductor layer, the first layer, and the third layer may be 50% or more.

[0026] According to an embodiment, the first semiconductor layer, the first layer, and the third layer may have Al x Ga 1-x The composition of N (0.5≤x≤0.6), and the fourth layer can have Al b Ga 1-b The composition formula of N(0.45≤b≤0.55).

[0027] According to an embodiment, the first conductivity type semiconductor layer may have Al z Ga 1-z The composition of N (0.45≤z≤0.55) is as follows: the quantum well layer of the active layer can be formed by AlGaN-based semiconductor, the quantum wall layer can be formed by AlGaN-based semiconductor, and the Al composition of the quantum wall layer can be 20% or more higher than the Al composition of the quantum well layer.

[0028] According to an embodiment, the thickness of the quantum well layer is 25% or less of the thickness of the quantum wall layer, and the active layer generates light from 295 nm to 315 nm.

[0029] According to an embodiment, the electron blocking layer may include a plurality of barrier layers and a plurality of well layers. The plurality of barrier layers may include AlGaN-based semiconductors, the plurality of well layers may include AlGaN-based semiconductors, each of the plurality of barrier layers may have an Al composition higher than that of each of the plurality of well layers, each of the plurality of barrier layers may have an Al composition higher than that of the quantum wall layer of the active layer, each of the plurality of well layers may have an Al composition lower than that of the quantum wall layer of the active layer, and the plurality of barrier layers may include a first barrier layer on the active layer and a second barrier layer below the second conductivity type semiconductor layer.

[0030] According to an embodiment, a plurality of well layers may be disposed between the first and second barrier layers, and the plurality of barrier layers may include a plurality of intermediate barrier layers disposed between the first and second barrier layers and the well layers, and the Al composition of each intermediate barrier layer may be higher than that of the first and second barrier layers.

[0031] According to an embodiment, the first barrier layer may have Al p Ga 1-p The composition of N (0.50≤p≤0.74) allows the second barrier layer to have Al q Ga 1-q The composition of N (0.50≤q≤0.74), and the intermediate barrier layer can have Al r Ga 1-r The composition formula of N (0.55≤r≤0.74).

[0032] According to an embodiment, each of the first barrier layer, the second barrier layer, and the intermediate barrier layer can be thicker than the well layer and can have a thickness of 3 nm to 10 nm, and the surface roughness of the second conductivity type semiconductor layer can be 1 nm or less.

[0033] According to an embodiment, the plurality of well layers may include a first well layer disposed between a first barrier layer and an intermediate barrier layer, a second well layer disposed between the intermediate barrier layers, and a third well layer disposed between the intermediate barrier layer and the second well layer. The first well layer may have Al e Ga 1-e The composition of N (0.24≤e≤0.45) allows the second well layer to have Al f Ga 1-f The composition of N (0.24≤f≤0.48) allows the third well layer to have Al g Ga 1-gThe composition of N (0.24≤g≤0.48) indicates that the second conductive semiconductor layer may include a first conductive semiconductor layer on the electron blocking layer and a second conductive semiconductor layer on the first conductive semiconductor layer, and the first conductive semiconductor layer may have Al s Ga 1-s The composition formula of N (0.20≤s≤0.45).

[0034] The light-emitting device package according to the embodiments may include: a package body; a heat sink connected to the package body; and an ultraviolet light-emitting device, including any one of the first to nineteenth types mounted on the heat sink.

[0035] The light-emitting module according to an embodiment includes: a circuit board; a light-emitting unit including a plurality of light-emitting device packages disposed on the circuit board and having a full width at half maximum (FWHM) of 17 nm or less; and a heat dissipation component disposed on the rear surface of the light-emitting unit, wherein the plurality of light-emitting device packages may have a first spacing in a first direction and a second spacing in a second direction perpendicular to the first direction, the first spacing and the second spacing being 30% to 50% of the width or diameter of the target area irradiated by light from the light-emitting unit. Therefore, the embodiment can realize a highly reliable light-emitting module with efficient UVB wavelengths for medical processing. Furthermore, the embodiment can achieve a target area uniformity of 70% or higher and can reduce the number of light-emitting device packages, thereby reducing the size and manufacturing cost of the light-emitting module.

[0036] The medical device according to the embodiment can achieve an efficient and reliable effective wavelength (300nm to 320nm) by including a light-emitting module and an optical compensator, and can achieve 70% or higher uniformity of the target area and reduce the number of light-emitting device packages, thereby reducing the size and manufacturing cost of the medical device.

[0037] A method for manufacturing an ultraviolet light-emitting device according to an embodiment includes: forming a first conductive semiconductor layer on a substrate; forming an active layer on a first conductivity type semiconductor layer; forming an electron blocking layer (EBL) on the active layer; and forming a second conductivity type semiconductor layer on the EBL, wherein forming the first conductivity type semiconductor layer includes: forming an AlN template on a substrate; forming a first superlattice layer on the AlN template; forming a first conductivity type first semiconductor layer on the first superlattice layer; and forming a second superlattice layer on the first superlattice layer, wherein the first conductivity type first semiconductor layer may include an Al component and overlaps with the first and second superlattice layers.

[0038] Beneficial effects

[0039] The embodiments realize UV ​​LEDs with a full width at half maximum (FWHM) of 17 nm or less, thus improving the reliability of UV LEDs used in medical devices.

[0040] By improving carrier injection efficiency through an EBL disposed on the active layer, the embodiments can achieve UVB from 295nm to 315nm with high current drive of 100mA or higher.

[0041] By providing a first semiconductor layer, a first superlattice layer, a first conductivity type semiconductor layer, and a second superlattice layer between the substrate and the active layer, the embodiments can improve defects and increase luminous efficiency.

[0042] The embodiment can improve optical power by using an active layer including a quantum well layer, the thickness of which is 10% to 25% of the thickness of the quantum wall layer.

[0043] The embodiments can improve reliability by using a second conductive first semiconductor layer with a thickness of 40 nm or more.

[0044] The embodiments can increase optical power and improve optical efficiency.

[0045] By achieving a light uniformity of 70% or higher for the ultraviolet wavelength irradiated by the light-emitting module onto the target area TA, the embodiments can improve the reliability of the light-emitting module used for light processing.

[0046] By implementing a light-emitting module with a high current drive of 200mA or higher and an effective wavelength (e.g., 300nm to 320nm) in the ultraviolet region, the reliability of the light-emitting module can be improved.

[0047] Examples of this invention may provide light-emitting modules and medical devices that can improve the reliability of medical or therapeutic ultraviolet wavelengths with a full width at half maximum (FWHM) of 17 nm or less.

[0048] In this embodiment, the number of light-emitting device packages and the size of the light-emitting module can be reduced by decreasing the spacing between the light-emitting device packages with ultraviolet light-emitting devices. Attached Figure Description

[0049] Figure 1 This is a plan view showing a light-emitting device according to an embodiment.

[0050] Figure 2 It is along Figure 1 A side sectional view of the light-emitting device along line I-I'.

[0051] Figure 3 It is shown Figure 2 A cross-sectional view of the electron blocking layer between the active layer and the second conductivity type semiconductor layer.

[0052] Figure 4 This is a view showing the band gap diagram of the electron blocking layer according to an embodiment.

[0053] Figure 5 It is shown Figure 2 Cross-sectional view of the AlN template layer, the first superlattice layer, the first semiconductor layer, the second superlattice layer, and the first conductivity type semiconductor layer.

[0054] Figure 6 This is a graph showing the optical power according to the thickness of the quantum wall layer of the active layer in accordance with an embodiment.

[0055] Figure 7 This is a graph illustrating the reliability of the thickness of the first conductive semiconductor layer of the second conductivity type semiconductor layer according to an embodiment.

[0056] Figure 8 This is a view showing the surface of a semiconductor layer of the second conductivity type in an embodiment.

[0057] Figures 9 to 13 This is a cross-sectional view illustrating a method for manufacturing a light-emitting device according to an embodiment.

[0058] Figure 14 This is a plan view showing a light-emitting device package having a light-emitting device according to an embodiment.

[0059] Figure 15 This is a perspective view showing a light-emitting module with a light-emitting device package according to an embodiment.

[0060] Figure 16 It is shown Figure 15 A plan view of the light-emitting unit of the light-emitting module.

[0061] Figure 17 It is shown Figure 16 A diagram showing the light uniformity of the light-emitting module.

[0062] Figure 18 It shows including Figure 15 A cross-sectional view of a medical device or UV lamp with a light-emitting module.

[0063] Figure 19 It is shown Figure 18 A diagram showing the light uniformity of the light-emitting module. Detailed Implementation

[0064] In the description of the embodiments, it should be understood that when a layer (or film), region, pattern, or structure is referred to as "above" or "below" another substrate, layer (or film), region, pattern, or structure, the term "above" or "below" includes both the meaning of "directly" and "indirectly" by inserting another layer. Furthermore, references to "above" or "below" for each layer will be based on the accompanying drawings.

[0065] Figure 1This is a plan view showing a light-emitting device according to an embodiment. Figure 2 It is along Figure 1 A cross-sectional view of the light-emitting device along line I-I' in the diagram. Figure 3 It is shown Figure 2 A detailed view of the electron blocking layer between the active layer and the second conductivity type semiconductor layer. Figure 4 This is a diagram illustrating the band gap of the electron blocking layer in an embodiment, and Figure 5 It is shown Figure 2 Cross-sectional view of the AlN template layer, the first superlattice layer, the first semiconductor layer, the second superlattice layer, and the first conductivity type semiconductor layer.

[0066] like Figures 1 to 5 As shown, the light-emitting device 100 according to an embodiment may include a light-emitting structure 110. The light-emitting device 100 according to an embodiment may include a substrate 101 and a light-emitting structure 110 on the substrate 101. The light-emitting device 100 of the embodiment can withstand a high current of 100 mA or higher. The light-emitting device 100 according to an embodiment includes a light-emitting structure 110 that generates light through a high current of 100 mA or higher. The light-emitting structure 110 can be driven by a high current of 100 mA or higher and emit UVB wavelengths. The light-emitting device 100 of the embodiment can emit UVB wavelengths from 295 to 315 nm. The light-emitting structure 110 of the embodiment can improve defects, increase luminous efficiency, increase optical power, and improve reliability. The light-emitting device 100 according to an embodiment may include an ultraviolet light-emitting device that emits UVB light.

[0067] like Figure 1 As shown, the top view shape of the light-emitting device 100 can be a polygonal shape, such as a rectangular shape. As another example, the top view shape of the light-emitting device 100 can be a circular shape, a square shape, or more shapes. The first electrode 151 and the second electrode 153 can be disposed on the light-emitting structure 110. The first electrode 151 and the second electrode 153 can be disposed at different heights, such as... Figure 2 As shown, however, the present invention is not limited thereto. When the light-emitting device 100 is polygonal, the light-emitting device 100 may include multiple side surfaces S1, S2, S3 and S4.

[0068] Regions A1 and A2, where the first electrode 151 is disposed, are exposed regions of a portion of the first conductivity type semiconductor layer 112b, and may be disposed outside regions A3 and A4, where the second electrode 153 is disposed. For example, the first region A1, where a portion of the first electrode 151 is disposed, is disposed around the third region A3, where a portion of the second electrode 153 is disposed. One or more second regions A2 may extend from the first region A1 along the direction of the third side surface S3, and one or more fourth regions A4 may extend from the third region A3 along the direction of the fourth side surface S4 opposite to the third side surface S3. The second regions A2 and the fourth regions A4 may be disposed alternately. Branch electrodes branching along the second region A2 may be disposed at the first electrode 151. Branch electrodes branching along the fourth region A4 may be disposed at the second electrode 153.

[0069] refer to Figure 2 The light-emitting structure 110 in the embodiment may include an AlN template layer 111, a first superlattice layer 120a, a first semiconductor layer 112a, a second superlattice layer 120b, a first conductivity type semiconductor layer 112b, an active layer 114, an electron blocking layer 130, second conductivity type semiconductor layers 116a and 116b, a first electrode 151, and a second electrode 153.

[0070] The substrate 101 can be formed of a material with excellent thermal conductivity and can be a conductive or insulating substrate. For example, the substrate 101 can be at least one of sapphire (Al2O3), SiC, Si, GaAs, GaN, ZnO, GaP, InP, Ge, and Ga2O3. Undulated structures can be formed on the upper surface of the substrate 101, but are not limited thereto. The substrate 101 can be removed.

[0071] AlN template layer 111 can be formed on substrate 101. AlN template layer 111 may include a buffer function. AlN template layer 111 can mitigate lattice mismatch between the material of the light-emitting structure 110 formed on AlN template layer 111 and the material of substrate 101. AlN template layer 111 can be formed of at least one of group III-V or group II-VI compound semiconductors, such as GaN, InN, InGaN, AlGaN, InAlGaN, and AlInN, in addition to AlN. AlN template layer 111 can improve defects caused by differences in the lattice constant of the AlGaN-based semiconductor layer grown on substrate 101. AlN template layer 111 can have a full-strain epitaxial structure, thereby improving the luminous efficiency during the growth of the semiconductor layer with ultraviolet wavelength. That is, by improving the crystallinity of the AlGaN-based semiconductor layer to be grown subsequently, AlN template layer 111 can improve the luminous efficiency of ultraviolet light-emitting device 100. AlN template layer 111 can be removed.

[0072] A first superlattice layer 120a may be disposed on an AlN template layer 111. A first semiconductor layer 112a may be disposed on a first superlattice layer 120a. A second superlattice layer 120b may be disposed on a first semiconductor layer 112a. A first conductivity type semiconductor layer 112b may be disposed on a second superlattice layer 120b. The first superlattice layer 120a, the first semiconductor layer 112a, the second superlattice layer 120b, and the first conductivity type semiconductor layer 112b may have an aluminum (Al) composition. Any one of the first superlattice layer 120a, the first semiconductor layer 112a, the second superlattice layer 120b, and the first conductivity type semiconductor layer 112b may comprise AlGaN or an AlGaN-based semiconductor.

[0073] As the first superlattice layer 120a, the first semiconductor layer 112a, the second superlattice layer 120b, and the first conductivity type semiconductor layer 112b become adjacent to the active layer 114, the aluminum (Al) composition can be gradually reduced. Therefore, the lattice mismatch and defects between the AlN template layer 111 and the active layer 114 can be improved.

[0074] A first superlattice layer 120a can be formed on the AlN template layer 111. The first superlattice layer 120a, disposed on the AlN template layer 111, can improve the lattice mismatch and defects between the material of the AlN template layer 111 and the material of the light-emitting structure 110 formed on the first superlattice layer 120a. Compared to the Al composition of the AlN template layer 111, the Al composition of the first superlattice layer 120a can be closer to the Al composition of the first semiconductor layer 112a. This first superlattice layer 120a can improve defects between layers grown on the AlN template layer 111.

[0075] like Figure 2 and Figure 5 As shown, the first superlattice layer 120a can be configured in two or more pairs, with at least two layers forming a pair. The first superlattice layer 120a may include, for example, a first layer 121a and a second layer 121b. The paired first layers 121a and second layers 121b may include 10 to 20 pairs and may be alternately configured. The first layer 121a may include an AlN semiconductor, and the second layer 121b may include AlGaN or an AlGaN-based semiconductor. The first layer 121a may be configured closer to or in contact with the AlN template layer 111. The second layer 121b may include materials with AlN... x Ga 1-xA semiconductor material with an N (0.5 ≤ x ≤ 0.6) composition. The first layer 121a may have 100% Al composition, and the second layer 121b may include 50% to 60% Al composition. The Al composition at the first layer 121a and the second layer 121b may be a composition excluding nitride semiconductors. In the embodiment, the thickness of each of the first layer 121a and the second layer 121b may be 5 nm or less, for example, 1 to 5 nm. When the first layer 121a and the second layer 121b are a pair, the number of both layers may be the same, or one of the layers may be more than the other.

[0076] When the first layer 121a and the second layer 121b have fewer than 10 pairs in the first superlattice layer 120a, the defect improvement effect may be reduced. When the first layer 121a and the second layer 121b have more than 20 pairs in the first superlattice layer 120a, the crystallinity may be reduced due to the difference in lattice constant. The second layer 121b may be AlGaN with a first conductivity type dopant. The second layer 121b may be an unintentionally doped (hereinafter abbreviated as UID) nitride semiconductor. For example, the second layer 121b may be AlGaN that unintentionally has a first conductivity type during the growth process. The concentration of the first layer 121a and the second layer 121b may be lower than the concentration of the first conductivity type dopant added to the first conductivity type semiconductor layer 112b. Either or both of the first layer 121a and the second layer 121b may be UID layers.

[0077] A first semiconductor layer 112a may be formed on a first superlattice layer 120a. The first semiconductor layer 112a may be implemented as, for example, a III-V or II-VI group compound semiconductor. The first semiconductor layer 112a may be formed from any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. The first semiconductor layer 112a may be disposed between the first superlattice layer 120a and the second superlattice layer 120b. The first semiconductor layer 112a may be in contact with the first superlattice layer 120a and the second superlattice layer 120b. The first semiconductor layer 112a may be a semiconductor different from the first layer 121a of the first superlattice layer 120a. The first semiconductor layer 112a may be the same semiconductor as the second layer 121b of the first superlattice layer 120a. The first semiconductor layer 112a may include a semiconductor having an Al composition. The Al composition of the first semiconductor layer 112a may be within the same range as the Al composition of the second layer 121b of the first superlattice layer 120a. Having the same Al composition range as the second layer 121b of the first superlattice layer 120a allows the first semiconductor layer 112a to absorb and remove defects from the first superlattice layer 120a. The first semiconductor layer 112a may include functions to improve lattice mismatch and defects between the first superlattice layer 120a and the second superlattice layer 120b. The Al composition of the first semiconductor layer 112a may be 50% or more, or it may be 60% or less.

[0078] The first semiconductor layer 112a in the embodiment may include having Al y Ga 1-yA semiconductor material with an N (0.5 ≤ y ≤ 0.6) composition. The first semiconductor layer 112a in this embodiment may include 50% to 60% Al composition. In this embodiment, the thickness of the first semiconductor layer 112a may be in the range of 10 to 1000 nm or 100 to 1000 nm. The thickness of the first semiconductor layer 112a may be set to be greater than the thickness of a single pair of first superlattice layers 120a. The thickness of the first semiconductor layer 112a may be set to be greater than the thickness of the first superlattice layer 120a. Such a first semiconductor layer 112a may be formed of a non-superlattice structure, with a thickness greater than the thickness of the first and second superlattice layers 120a and 120b, and may be used as a buffer layer between the first and second superlattice layers 120a and 120b. In one embodiment, a first semiconductor layer 112a with a thickness of 200 nm is described as an example, but is not limited thereto. The first semiconductor layer 112a may be doped with a first conductivity type dopant. When the first conductivity type dopant is an n-type semiconductor layer, the first conductivity type dopant may include, but is not limited to, Si, Ge, Sn, Se, or Te as an n-type dopant. As another example, the first semiconductor layer 112a may be a UID semiconductor. The first semiconductor layer 112a may be a single layer or multiple layers.

[0079] like Figure 2 and Figure 5 As shown, a second superlattice layer 120b can be formed on the first semiconductor layer 112a. The second superlattice layers 120b can be arranged in two or more pairs, with at least two layers forming a pair. The second superlattice layer 120b may include a third layer 123a and a fourth layer 123b, and each of the third and fourth layers 123a and 123b can be multiple. The third and fourth layers 123a and 123b can be arranged alternately. Any one or both of the third and fourth layers 123a and 123b can be the same semiconductor, for example, AlGaN as the first semiconductor layer 112a. Any one of the third and fourth layers 123a and 123b can have the same Al composition range as the first semiconductor layer 112a. Here, the same Al composition can include the Al composition range of the first semiconductor layer 112a. The other of the third and fourth layers 123a and 123b can be a semiconductor with an Al composition different from that of the first semiconductor layer 112a. The second superlattice layer 120b may be disposed on the first semiconductor layer 112a to include the function of improving lattice mismatch and defects between the material of the first semiconductor layer 112a and the material of the light-emitting structure 110 formed on the second superlattice layer 120b. The second superlattice layer 120b may include 10 to 20 pairs of alternately formed third layers 123a and fourth layers 123b. When the third layer 123a and the fourth layer 123b are a pair, the number of both layers may be the same, or one of the layers may be more.

[0080] The third layer 123a may include having Al a Ga 1-a Semiconductor materials with an N (0.5 ≤ a ≤ 0.6) composition. The third layer 123a may include 50% to 60% Al composition, and the thickness of each third layer 123a in the embodiments may be 5 nm or less, for example, 1 to 5 nm. Here, the second layer 121b of the first superlattice layer 120a, the first semiconductor layer 112a, and the third layer 123a of the second superlattice layer 120b may have the same Al composition range. The second layer 121b of the first superlattice layer 120a, the first semiconductor layer 112a, and the third layer 123a of the second superlattice layer 120b may have a lower Al composition than the first layer 121a, and may have a higher Al composition than the quantum wall layer of the active layer 114.

[0081] When the third and fourth layers 123a and 123b and the first semiconductor layer 112a have an Al composition ratio of Al in the AlGaN-based semiconductor formula, x Compared with Ga composition, Ga y At that time, the third and fourth layers 123a and 123b and the first semiconductor layer 112a can have Al x ≥Ga y The component ratio relationship, and Al x and Ga y The difference in composition ratio can be 10% or less. When the AlGaN-based semiconductor of the third and fourth layers 123a and 123b and the first semiconductor layer 112a has an Al composition ratio of 10%, the composition ratio of the AlGaN-based semiconductor is 10%. x <Ga y When the composition ratio is adjusted, the semiconductor crystal can be improved, but this may increase light absorption loss. When Al... x and Ga yWhen the compositional difference exceeds 10%, it may affect the light absorption loss at ultraviolet wavelengths or the semiconductor crystal. In one embodiment, the third and fourth layers 123a and 123b, and the first semiconductor layer 112a, can optimize the component ratio in the AlGaN-based semiconductor composition to improve the semiconductor crystal and reduce light absorption loss at ultraviolet wavelengths. Furthermore, due to the Al composition range and differences of the third and fourth layers 123a and 123b, and the first semiconductor layer 112a, defects transported from the first superlattice layer 120a can be absorbed and removed. This can include functions to improve lattice mismatch and defects at the interfaces between the first layer 121a and the second layer 121b of the first superlattice layer 120a, and the third and fourth layers 123b of the second superlattice layer 120b and the first semiconductor layer 112a. The crystallinity of the AlGaN-based semiconductor layer can be improved, thus increasing the luminous efficiency of ultraviolet light. When the active layer 114 emits a UVB wavelength or a wavelength of 295 to 315 nm, the AlGaN-based semiconductors of the third and fourth layers 123a and 123b and the first semiconductor layer 112a can be provided with an Al composition difference of 40% or more as described above, thereby improving the crystallinity during semiconductor layer growth.

[0082] The fourth layer 123b may include having Al b Ga 1-b A semiconductor material with an N (0.45 ≤ b ≤ 0.55) composition. The fourth layer 123b may include 45% to 55% Al composition. The thickness of each fourth layer 123b in the embodiment may be 5 nm or less, for example, 1 to 5 nm. The thickness of a single pair of second superlattice layers 120b may be less than the thickness of the first semiconductor layer 112a. The thickness of the second superlattice layer 120b may be less than the thickness of the first semiconductor layer 112a. The fourth layer 123b may have a lower Al composition than the third layer 123a. The fourth layer 123b may have an Al composition that is 5% or more lower than the Al composition of the third layer 123a. The fourth layer 123b may be doped with a first conductivity type dopant. When the first conductivity type dopant is an n-type semiconductor layer, the first conductivity type dopant may include, but is not limited to, Si, Ge, Sn, Se, or Te as an n-type dopant. The first semiconductor layer 112a may be a UID nitride semiconductor. Here, when the first conductivity type dopant is an n-type semiconductor layer, the first conductivity type dopant may include, but is not limited to, Si, Ge, Sn, Se, or Te as an n-type dopant. In one embodiment, the Al composition gradually decreases from the AlN template layer 111 to the active layer 114, thereby improving crystallinity. Any one or both of the third and fourth layers 123a and 123b may be UID semiconductors.

[0083] A first conductivity type semiconductor layer 112b can be formed on the second superlattice layer 120b. The first conductivity type semiconductor layer 112b can be implemented as, for example, a III-V or II-VI group compound semiconductor. For example, the first conductivity type semiconductor layer 112b can be formed from any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. The first conductivity type semiconductor layer 112b in the embodiment may include Al... z Ga 1-z A semiconductor material with an N (0.45≤z≤0.55) composition. When the first conductivity type semiconductor layer 112b is in contact with the second superlattice layer 120b, the Al composition of the first conductivity type semiconductor layer 112b can be the same as or lower than the Al composition of the fourth layer 123b. Therefore, due to the difference in Al composition, the first conductivity type semiconductor layer 112b can prevent the deterioration of the crystal quality of the active layer 114.

[0084] The first conductivity type semiconductor layer 112b in this embodiment may include 45% to 55% Al composition, and the thickness of the first conductivity type semiconductor layer 112b in this embodiment may be 500 to 1000 nm. The thickness of the first conductivity type semiconductor layer 112b may be greater than the thickness of the first superlattice layer 120a, and the thickness of the first semiconductor layer 112a and the second superlattice layer 120b. Figure 1 As shown, in the first conductivity type semiconductor layer 112b, certain regions, such as the first and second regions A1 and A2, can be positioned below the active layer 114. In one embodiment, a first conductivity type semiconductor layer 112b with a thickness of 1000 nm is described as an example, but is not limited thereto. The first conductivity type semiconductor layer 112b may be doped with a first conductivity type dopant. A first electrode 151 may be disposed on the first conductivity type semiconductor layer 112b, such as... Figure 2As shown. The first conductivity type semiconductor layer 112b can be an electrode contact layer. The first electrode 151 disposed on the first conductivity type semiconductor layer 112b is described as an example, but the first electrode 151 can be connected to the first conductivity type semiconductor layer 112b through a via structure through the substrate 101, or through a via structure through the second conductivity type semiconductor layers 116a and 116b. The first electrode 151 can be connected to the second superlattice layer 120b instead of the first conductivity type semiconductor layer 112b, but is not limited thereto. The active layer 114 can be formed as at least one of a single quantum well structure, a multiple quantum well (MQW) structure, a quantum wire structure, and a quantum dot structure. The active layer 114 is a layer in which electrons (or holes) injected through the first conductivity type semiconductor layer 112b and holes (or electrons) injected through the second conductivity type semiconductor layers 116a and 116b meet each other, and emits light by means of the band gap difference of the energy bands of the materials forming the active layer 114.

[0085] The active layer 114 may be made of a compound semiconductor. As an example, the active layer 114 may be implemented using at least one of group III-V or II-VI compound semiconductors. The active layer 114 may include a quantum well layer and a quantum wall layer. Multiple quantum well layers and multiple quantum wall layers may be configured. When the active layer 114 is implemented using an MQW structure, the quantum well layers and quantum wall layers may be alternately configured. The quantum well layers and quantum wall layers may be formed in any one or more pairs of structures, but are not limited to, AlGaN / GaN, AlGaN / AlGaN, InGaN / GaN, InGaN / InGaN, InAlGaN / GaN, GaAs / AlGaAs, InGaAs / AlGaAs, GaP / AlGaP, and InGaP / AlGaP.

[0086] The active layer 114 may include AlGaN or an AlGaN-based semiconductor to emit ultraviolet wavelengths. In the active layer 114, the quantum well layer may include an AlGaN-based semiconductor, and the quantum wall layer may include an AlGaN-based semiconductor. The Al composition of the quantum well layer may be lower than that of the quantum wall layer, and for example, based on the Al composition of the quantum wall layer, it may be 20% or less. The Al composition of the quantum well layer may be 30% or less, for example, in the range of 15% to 30%, and the Al composition of the quantum wall layer may be in the range of 45% to 52%. The Al composition of the quantum wall layer may differ from that of the quantum well layer by 20% or more, for example, in the range of 20-30%. The active layer 114 can emit ultraviolet light through the difference in the Al composition ratio of the quantum well layer and the quantum wall layer. The active layer 114 can emit light with UVB wavelengths. The active layer 114 can emit UVB in the range of 295 to 315 nm. Ultraviolet B (UVB) has a shorter wavelength than ultraviolet A (UVA), and its light beam has a higher energy intensity. This UVB can be used as a medical light source. The ultraviolet light emitted from the active layer 114 in this embodiment can have a full width at half maximum (FWHM) of 17 nm or less.

[0087] In the active layer 114, the thickness of the quantum well layer can be thinner than the thickness of the quantum wall layer. The thickness of the quantum well layer can be 25% or less of the thickness of the quantum wall layer, for example, in the range of 10% to 25%. That is, the thickness of the quantum wall layer can be four times or more of the thickness of the quantum well layer, for example, four to ten times. (See reference...) Figure 6 In this embodiment, the active layer 114 can improve optical power by using quantum well layers with a thickness of 10% to 25% of the thickness of the quantum wall layer. For example, each quantum well layer can be 2.5 nm or smaller, such as 1.5 nm to 2.5 nm. Figure 6 This diagram illustrates the optical power based on the thickness of the quantum well layers of the active layer 114 with a quantum wall layer of 10.9 nm, and shows the highest optical power in a quantum well layer with a thickness of 2.1 nm. When the thickness of each quantum well layer is less than 10% or greater than 25% of the thickness of each quantum wall layer, crystallinity or carrier mobility may deteriorate. When the thickness of each quantum well layer is outside the range of 10% to 25% of the thickness of each quantum wall layer, the recombination rate of electrons and holes from the active layer 114 may decrease, and the optical power may deteriorate.

[0088] Reference Figure 3 and Figure 4An electron blocking layer (EBL) 130 may be formed on the active layer 114. The electron blocking layer 130 may be disposed between the active layer 114 and the second conductivity type semiconductor layers 116a and 116b. The EBL 130 may include a multilayer structure, and at least one or all of the multilayers may include a second conductivity type dopant. The electron blocking layer 130 may include AlGaN or an AlGaN-based semiconductor to reduce absorption at ultraviolet wavelengths and block electrons.

[0089] The EBL 130 of the embodiment may include multiple barrier layers 131, 133, 135, and 137, and multiple well layers 132, 134, and 136. Any one or more of the barrier layers 131, 133, 135, and 137 and the well layers 132, 134, and 136 may be the same, or there may be more of any one type of layer. The EBL 130 may be formed of a III-V or II-VI compound semiconductor, for example, the EBL 130 may be formed of three or more pairs of AlGaN / AlGaN, but is not limited thereto. At least one or all of the EBL 130 may be doped with a second conductivity type dopant. For example, when the EBL 130 is a p-type semiconductor layer, the second conductivity type dopant may include Mg, Zn, Ca, Sr, or Ba as a p-type dopant. The EBL 130 of the embodiment may include a function to increase the number of charge carriers provided to the active layer 114 to achieve a 295-315 nm UVB driven by a high current of 100 mA or higher. Additionally, the EBL 130 may include an electron blocking function to block electrons, thereby improving luminous efficiency. The EBL 130 may be configured such that multiple barrier layers 131, 133, 135, and 137 and multiple well layers 132, 134, and 136 alternate in three or more pairs. The multiple barrier layers 131, 133, 135, and 137 and the multiple well layers 132, 134, and 136 may include a second conductivity type dopant. The thickness of the well layers 132, 134, and 136 may be relatively thinner than the thickness of the barrier layers 131, 133, 135, and 137, such that the second conductivity type dopant may not be doped. The multiple barrier layers 131, 133, 135 and 137 and the multiple well layers 132, 134 and 136 in the embodiment can improve luminous efficiency through Al composition and thickness.

[0090] EBL 130 can prevent electrons that have already passed through the active layer 114 from overflowing, thereby improving internal quantum efficiency. For example... Figure 4 As shown, the quantum wall layer 114a based on the active layer 114 (see...) Figure 4The energy level reference (REF) of EBL 130 includes barrier layers 131, 133, 135, and 137 with higher energy levels and well layers 132, 134, and 136 with lower energy levels. The quantum wall layer may be the last quantum wall layer of the active layer 114. The last quantum wall layer of the active layer 114 may have the same Al composition as the other quantum wall layers.

[0091] The barrier layers 131, 133, 135, and 137 of the EBL 130 can have a greater quantum wall layer 114a than the active layer 114 (see [link to relevant documentation]). Figure 4 With a higher Al composition, well layers 132, 134, and 136 can have a final quantum wall layer 114a that is higher than that of active layer 114 (see [link to relevant documentation]). Figure 4 The lower Al composition. The final quantum wall layer 114a of the active layer 114 (see...) Figure 4 The active layer 114 may contain 45% to 52% Al content, and the multiple barrier layers 131, 133, 135, and 137 may contain 50% or more Al content. The final quantum wall layer 114a of the active layer 114 may have a lower Al content than the barrier layers 131, 133, 135, and 137. The Al content of the barrier layers 131, 133, 135, and 137 may be 3% or more higher than the Al content of the final quantum wall layer 114a of the active layer 114.

[0092] The Al composition of EBL 130 can block electrons and confine holes to improve luminescence efficiency by increasing carrier injection in the active layer 114.

[0093] The plurality of barrier layers 131, 133, 135, and 137 may include a first barrier layer 131 adjacent to the active layer 114, a second barrier layer 137 adjacent to the second conductivity type semiconductor layers 116a and 116b, and intermediate barrier layers 133 and 135 between the first barrier layer 131 and the second barrier layer 137. Here, the intermediate barrier layers 133 and 135 may be one or more. In the case of multiple barrier layers 133 and 135, a first intermediate barrier layer 133 between the first barrier layer 131 and the second barrier layer 137 and a second intermediate barrier layer 135 between the first intermediate barrier layer 133 and the second barrier layer 137 may be included.

[0094] The first barrier layer 131 may contact the last quantum wall layer 114a of the active layer 114. The second barrier layer 137 may contact the lower surfaces of the second conductivity type semiconductor layers 116a and 116b.

[0095] Multiple well layers 132, 134, and 136 may include a first well layer 132 between a first barrier layer 131 and a first intermediate barrier layer 133, a second well layer 134 between a first intermediate barrier layer 133 and a second intermediate barrier layer 135, and a third well layer 136 between a second intermediate barrier layer 135 and a second barrier layer 137. The EBL 130 of this embodiment includes, but is not limited to, multiple barrier layers 131, 133, 135, and 137, and multiple well layers 132, 134, and 136 in three pairs of structures. The first barrier layer 131 may have a higher Al composition than the last quantum wall layer 114a of the active layer 114. For example, the first barrier layer 131 may include layers with Al... p Ga 1-p A semiconductor material with an N (0.50 ≤ p ≤ 0.74) composition. The first barrier layer 131 of the embodiment may include 50% to 74% Al content, and the thickness W1 of the first barrier layer 131 of the embodiment may be greater than the thickness W2 of the first well layer 132. The thickness W1 of the first barrier layer 131 of the embodiment may be 10 nm or less, for example, 3 nm to 10 nm.

[0096] The second barrier layer 137 may have a higher Al content than the second conductivity type semiconductor layers 116a and 116b. For example, the second barrier layer 137 may include layers with Al content... q Ga 1-q A semiconductor material with an N (0.50 ≤ q ≤ 0.74) composition. The second barrier layer 137 in this embodiment may include 50% to 74% Al content, and the thickness W7 of the second barrier layer 137 in this embodiment may be greater than the thickness W6 of the third well layer 136. The thickness W7 of the second barrier layer 137 in this embodiment may be 10 nm or less, for example, 3 to 10 nm. The second barrier layer 137, having an Al content of 50% to 74% and a thickness of 10 nm or less, can therefore block electrons, improve carrier injection efficiency, and reduce light absorption loss at ultraviolet wavelengths.

[0097] The Al composition of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 can be the same or have a difference of less than 1%, and can be higher than the Al composition of the first barrier layer 131 and the second barrier layer 137. An EBL 130 with this Al composition can improve hole injection. For example, the EBL 130 can improve luminous efficiency by confining holes in the first intermediate barrier layer 133 and the second intermediate barrier layer 135, thereby increasing carrier injection into the active layer 114. The first intermediate barrier layer 133 and the second intermediate barrier layer 135 may include Al... r Ga 1-rSemiconductor materials with an N (0.55 ≤ r ≤ 0.74) composition. The first intermediate barrier layer 133 and the second intermediate barrier layer 135 of the embodiment may contain 55% to 74% Al composition. The thicknesses W3 and W5 of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 of the embodiment may be thicker than the thickness W4 of the second well layer 134. The thicknesses W3 and W of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 of the embodiment may be 10 nm or less, for example, 3 to 10 nm. For example, when the EBL 130 includes a first barrier layer 131 and a second barrier layer 137 with 54% Al composition and a first intermediate barrier layer 133 and a second intermediate barrier layer 135 with 64% Al composition, the output voltage may be 30% or more higher than the output voltage of a comparative ultraviolet light-emitting device with a composition lower than the aforementioned Al composition.

[0098] The plurality of well layers 132, 134 and 136 may include: a first well layer 132 between a first barrier layer 131 and a first intermediate barrier layer 133, a second well layer 134 between a first intermediate barrier layer 133 and a second intermediate barrier layer 135, and a third well layer 136 between a second intermediate barrier layer 135 and a second barrier layer 137.

[0099] The first well layer 132 may include an Al composition lower than that of the final quantum wall layer 114a of the active layer 114. The first well layer 132 may include layers with Al... e Ga 1-e Semiconductor materials with an N (0.24 ≤ e ≤ 0.45) composition. The thickness W2 of the first well layer 132 in this embodiment can be thinner than the thickness W1 of the first barrier layer 131 and the thickness W3 of the first intermediate barrier layer 133. In one embodiment, the thickness W2 of the first well layer 132 can be 5 nm or less, for example, 1 to 5 nm.

[0100] The second well layer 134 may include an Al composition lower than that of the final quantum wall layer 114a of the active layer 114. The second well layer 134 may include Al... f Ga 1-f Semiconductor materials with an N (0.24 ≤ f ≤ 0.48) composition. The thickness W4 of the second well layer 134 in this embodiment can be thinner than the thicknesses W3 and W5 of the first intermediate barrier layer 133 and the second intermediate barrier layer 135. The thickness W4 of the second well layer 134 in this embodiment can be 5 nm or less, for example, 1 to 5 nm.

[0101] The third well layer 136 may include an Al composition lower than that of the final quantum wall layer 114a of the active layer 114. The third well layer 136 may include layers with Al... g Ga 1-gSemiconductor materials with an N (0.24 ≤ g ≤ 0.48) composition. The thickness W6 of the third well layer 136 in this embodiment can be thinner than the thickness W5 of the second intermediate barrier layer 135 and the thickness W7 of the second barrier layer 137. The thickness W6 of the third well layer 136 in this embodiment can be 5 nm or less, for example, 1 to 5 nm. The second and third well layers 134 and 136 can have the same Al composition and thickness, but are not limited thereto. The Al composition of the second and third well layers 134 and 136 can be higher than the Al composition of the first well layer 132.

[0102] Due to the differences in Al composition or barriers between the multiple barrier layers 131, 133, 135 and 137 and the well layers 132, 134 and 136, EBL 130 can prevent electron overflow and thus improve internal quantum efficiency.

[0103] like Figure 4 As shown, the band gaps G1, G3, G5, and G7 of the multiple barrier layers 131, 133, 135, and 137 are greater than the band gap G0 of the last quantum wall layer 114a of the active layer 114. When the band gap of the first barrier layer 131 is G1, the band gaps of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 are G3 and G5, and the band gap of the second barrier layer 137 is G7, the band gaps can have the relationship G3, G5>G1, G7>G0.

[0104] The band gaps G2, G4, and G6 of the multiple well layers 132, 134, and 136 can be smaller than the band gap G0 of the last barrier layer 114a of the active layer 114. When the band gap of the first well layer 132 is G2, the band gap of the second well layer 134 is G4, and the band gap of the third well layer 136 is G6, the band gaps can have the relationship G0>G2>G4, G6.

[0105] In one embodiment, the EBL 130 can be disposed on the active layer 114 to improve carrier injection efficiency, thereby improving luminescence efficiency. One embodiment can achieve a high current-driven UVB of 295 to 315 nm at 100 mA or higher.

[0106] Second conductivity type semiconductor layers 116a and 116b can be disposed on EBL 130. The second conductivity type semiconductor layers 116a and 116b can be formed as a single layer or multiple layers, and in the case of multiple layers, the multiple layers may include a first conductive semiconductor layer 116a and a second conductive semiconductor layer 116b. The first conductive semiconductor layer 116a can be disposed on EBL 130 and can be disposed between EBL 130 and the second conductive semiconductor layer 116b. The first and second conductive semiconductor layers 116a and 116b can be semiconductors with a second conductivity type dopant.

[0107] The first conductive semiconductor layer 116a can be implemented as, for example, a III-V or II-VI group compound semiconductor. For example, the first conductive semiconductor layer 116a can be formed from any or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. The first conductive semiconductor layer 116a may include AlGaN or AlGaN-based semiconductors to reduce absorption at ultraviolet wavelengths. The first conductive semiconductor layer 116a in the embodiment may include Al... s Ga 1-s Semiconductor materials with an N (0.20 ≤ s ≤ 0.45) composition. The first conductive semiconductor layer 116a may include 20% to 45% Al composition.

[0108] The thickness of the first conductive semiconductor layer 116a can be 40 nm or greater. Figure 7 This is a graph illustrating the reliability of the thickness of the first conductive semiconductor layer according to an embodiment. (Refer to...) Figure 7 When the first conductive semiconductor layer 116a of the embodiment has a thickness of 40 nm or greater, the output voltage changes constantly over time, thus improving reliability. The thickness of the first conductive semiconductor layer 116a in the embodiment can be 40 nm or greater, for example, 40 to 300 nm. The first conductive semiconductor layer 116a can be doped with a second conductivity type dopant. In the case that the first conductive semiconductor layer 116a is a p-type semiconductor layer, the second conductivity type dopant can include Mg, Zn, Ca, Sr, or Ba as a p-type dopant. When the thickness of the first conductive semiconductor layer 116a in the embodiment is less than 40 nm, the reliability may deteriorate because the output voltage gradually decreases according to the driving time of the ultraviolet light-emitting device 100.

[0109] Here, although the first conductivity type semiconductor layer 112b is described as an n-type semiconductor layer and the second conductivity type semiconductor layers 116a and 116b are described as p-type semiconductor layers, the first conductivity type semiconductor layer 112b can be formed as a p-type semiconductor layer, and the second conductivity type semiconductor layers 116a and 116b can be formed as n-type semiconductor layers, and are not limited thereto. A semiconductor, for example, an n-type semiconductor layer (not shown) having a polarity opposite to that of the second conductivity type, can be formed on the first conductivity semiconductor layer 116a and the second conductivity semiconductor layer 116b. Therefore, the light-emitting structure 110 can be implemented as any of the np junction structure, pn junction structure, npn junction structure, and pnp junction structure.

[0110] The second conductive semiconductor layer 116b can be formed on the first conductive semiconductor layer 116a. The second conductive semiconductor layer 116b can be an electrode contact layer that contacts the second electrode 153. The second conductive semiconductor layer 116b can be formed of a semiconductor different from the first conductive semiconductor layer 116a. For example, the second conductive semiconductor layer 116b can have a lower Al content than the first conductive semiconductor layer 116a, or it can be a GaN-based semiconductor without Al content. The second conductive semiconductor layer 116b can be disposed between the first conductive semiconductor layer 116a and the second electrode 153 for an ohmic contact between the first conductive semiconductor layer 116a and the second electrode 153. The second conductive semiconductor layer 116b can be GaN of a second conductivity type or a dopant of a second conductivity type, used for an ohmic contact between the first conductive semiconductor layer 116a and the second electrode 153, but is not limited thereto. The surface of the second conductive semiconductor layer 116b that directly contacts the second electrode 153 can be flat. For this purpose, the second conductive semiconductor layer 116b can be formed by a two-dimensional (D) growth method. The surface of the second conductive semiconductor layer 116b can be formed as a rough surface. Figure 8 This is a view showing the surface of the second conductive semiconductor layer 116b according to an embodiment. The second conductive semiconductor layer 116b of this embodiment has a thickness of 50 nm or less, serves as an ohmic contact between the first conductive semiconductor layer 116a and the second electrode 153, and has a surface roughness (RMS) of 1 nm or less, for example, 0.1 to 1.0 nanometers. The second conductive semiconductor layer 116b of this embodiment may include a surface roughness (RMS) of 1 nm or less to improve the reliability of contact with the subsequently formed second electrode 153.

[0111] The first electrode 151 may be disposed on the first conductivity type semiconductor layer 112b. The first electrode 151 may be electrically connected to the first conductivity type semiconductor layer 112b. The first electrode 151 may be electrically insulated from the second electrode 153. The first electrode 151 may be a conductive oxide, a conductive nitride, or a metal. The first electrode 151 may include a contact layer, and the contact layer may include, for example, at least one of indium tin oxide (ITO), ITO nitride (ITON), indium zinc oxide (IZO), IZO nitride (IZON), zinc aluminum oxide (AZO), zinc aluminum gallium oxide (AGZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), antimony tin oxide (ATO), zinc gallium oxide (GZO), IZO nitride (IZON), ZnO, IrOx, RuOx, NiO, Au, Cu, Ni, Ti, Ti-W, Cr, W, Pt, V, Fe and Mo, and may be formed as a single layer or multiple layers.

[0112] The second electrode 153 may be disposed on the second conductive semiconductor layer 116b. The second electrode 153 may be electrically connected to the second conductive semiconductor layer 116b. The second electrode 153 may be a conductive oxide, a conductive nitride, or a metal. The second electrode 153 may include a contact layer, for example, the contact layer may include at least one of ITO, ITO, IZO, IZON, AZO, AGZO, IZTO, IAZO, IGZO, IGTO, ATO, GZO, IZON, ZnOIrOx, RuOx, NiO, Au, Cu, Ni, Ti, Ti-W, Cr, W, Pt, V, Fe, and Mo, and may be formed as a single layer or multiple layers.

[0113] The ultraviolet light-emitting device 100 of the embodiment may have a full width at half maximum (FWHM) of 17 nm or less. Typically, ultraviolet light-emitting devices with an FWHM of 20 nm or greater, at 300 nm or less, particularly 298 nm or less, damage DNA, proteins, etc., and are therefore difficult to apply in medical devices such as those requiring atopy treatment. In one embodiment, each quantum well layer of the active layer 114 may include a thickness of 10% to 25% of the thickness of each quantum wall layer to achieve an FWHM of 17 nm or less, thereby improving the reliability of the ultraviolet light-emitting device for use in medical devices.

[0114] In the ultraviolet light-emitting device 100 of the embodiment, an EBL 130 is disposed on the active layer 114 to enhance carrier injection efficiency, thereby enabling high current drive of 100mA or higher. Specifically, in one embodiment, by using an EBL 130 structure having a higher Al composition than the first barrier layer 131 and the second barrier layer 137, the first intermediate barrier layer 133 and the second intermediate barrier layer 135 can achieve a high current drive of 295 to 315 nm UVB of 100mA or higher.

[0115] In one embodiment, a first semiconductor layer 112a, a first superlattice layer 120a, a first conductivity type semiconductor layer 112b, and a second superlattice layer 120b may be included between the substrate 101 and the active layer 114 to improve defects and thus improve luminous efficiency.

[0116] In one embodiment, optical power can be improved by including a quantum well layer with a thickness of 10% to 25% of the thickness of the quantum wall layer in the active layer 114.

[0117] In one embodiment, reliability can be improved by using a first conductive semiconductor layer 116a with a thickness of 40 nm or greater.

[0118] In one embodiment, a wavelength ultraviolet light-emitting device 100 with a current of 100 mA or greater and wavelengths of 295 to 315 nm can be realized and applied to medical devices such as those with Atopy processing.

[0119] Figures 9 to 13 This is a cross-sectional view illustrating a method for manufacturing an ultraviolet light-emitting device according to an embodiment.

[0120] Reference Figure 9 In the method for manufacturing an ultraviolet light-emitting device according to an embodiment, an AlN template layer 111, a first superlattice layer 120a, a first semiconductor layer 112a, a second superlattice layer 120b, and a first conductivity type semiconductor layer 112b may be formed on a substrate 101.

[0121] The substrate 101 can be formed of a material with excellent thermal conductivity and can be a conductive substrate or an insulating substrate. For example, at least one of sapphire (Al2O3), SiC, Si, GaAs, GaN, ZnO, GaP, InP, Ge, and Ga2O3 can be used as the substrate 101. Undulated structures can be formed on the substrate 101, but are not limited thereto.

[0122] The AlN template layer 111, the first superlattice layer 120a, the first semiconductor layer 112a, the second superlattice layer 120b, and the first conductivity type semiconductor layer 112b can be formed by metal-organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE), but are not limited to these methods.

[0123] The AlN template layer 111, the first superlattice layer 120a, the first semiconductor layer 112a, the second superlattice layer 120b, and the first conductivity type semiconductor layer 112b can be grown at a pressure of 100 mPa or lower.

[0124] AlN template layer 111 can be formed on substrate 101. AlN template layer 111 may include a buffer function. AlN template layer 111 can mitigate the lattice mismatch between the material of the light-emitting structure 110 formed on AlN template layer 111 and the material of substrate 101. AlN template layer 111 can be formed of at least one of group III-V or group II-VI compound semiconductors, such as GaN, InN, InGaN, AlGaN, InAlGaN, and AlInN, in addition to AlN.

[0125] A first superlattice layer 120a can be disposed on the AlN template layer 111. A first semiconductor layer 112a can be disposed on the first superlattice layer 120a. A second superlattice layer 120b can be disposed on the first semiconductor layer 112a. A first conductivity type semiconductor layer 112b can be disposed on the second superlattice layer 120b. The Al composition of the first superlattice layer 120a, the first semiconductor layer 112a, the second superlattice layer 120b, and the first conductivity type semiconductor layer 112b gradually decreases, thereby improving the lattice mismatch and defects between the AlN template layer 111 and the active layer 114.

[0126] A first superlattice layer 120a can be formed on an AlN template layer 111. The first superlattice layer 120a, disposed on the AlN template layer 111, enables the improvement of lattice mismatch and defects between the material of the AlN template layer 111 and the material of the light-emitting structure 110 formed on the first superlattice layer 120a. The first superlattice layer 120a may include a first layer 121a and a second layer 121b, which are alternately formed in 10 to 20 pairs. The second layer 121b may include materials with Al... x Ga 1-x A semiconductor material with an N (0.5 ≤ x ≤ 0.6) composition. The second layer 121b may include 50% to 60% Al composition, and each of the first layer 121a and the second layer 121b may have a thickness of 1 to 5 nm. When the first layer 121a and the second layer 121b have fewer than 10 pairs in the first superlattice layer 120a, the defect improvement effect may deteriorate. When the first layer 121a and the second layer 121b have more than 20 pairs in the first superlattice layer 120a, the crystallinity may decrease due to the difference in lattice constant. The second layer 121b may be AlGaN of a first conductivity type. The second layer 121b may be GaN unintentionally doped. For example, the second layer 121b may be AlGaN that unintentionally has a first conductivity type during the growth process.

[0127] A first semiconductor layer 112a may be formed on a first superlattice layer 120a. The first semiconductor layer 112a may be implemented as, for example, a III-V or II-VI group compound semiconductor. For example, the first semiconductor layer 112a may be formed from any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. The first semiconductor layer 112a in the embodiment may include Al... y Ga 1-yA semiconductor material with an N (0.5 ≤ y ≤ 0.6) composition. The first semiconductor layer 112a of the embodiment may include 50% to 60% Al composition, and the thickness of the first semiconductor layer 112a may be 10 to 1000 nm. In one embodiment, a first semiconductor layer 112a with a thickness of 200 nm is described as an example. The first semiconductor layer 112a may be doped with a first conductivity type dopant. When the first conductivity type dopant is an n-type dopant, the first conductivity type dopant may include Si, Ge, Sn, Se, or Te as an n-type dopant, but is not limited thereto.

[0128] The second superlattice layer 120b may be formed on the first semiconductor layer 112a. The second superlattice layer 120b may be disposed on the first semiconductor layer 112a to include the function of improving lattice mismatch and defects between the material of the first semiconductor layer 112a and the material of the light-emitting structure 110 formed on the second superlattice layer 120b. The second superlattice layer 120b may include 10 to 20 pairs of alternately formed third layers 123a and fourth layers 123b.

[0129] The third layer 123a may include having Al a Ga 1-a The semiconductor material has an N (0.5 ≤ a ≤ 0.6) composition. The third layer 123a may include 50% to 60% Al composition. The thickness of each third layer 123a in the embodiment may be 1 to 5 nm. The Al composition of the third layer 123a can be set within the Al composition range of the first semiconductor layer 112a. Therefore, lattice mismatch and defects on the first semiconductor layer 112a can be improved.

[0130] The fourth layer 123b may include having Al b Ga 1-b A semiconductor material with an N (0.45 ≤ b ≤ 0.55) composition. The fourth layer 123b may include 45% to 55% Al composition. The thickness of each fourth layer 123b in the embodiment may be 1 to 5 nm. The fourth layer 123b may have a lower Al composition than the third layer 123a. At least one or both of the third and fourth layers 123a and 123b may include a first conductivity type dopant. Here, when the first conductivity type dopant is an n-type dopant, the first conductivity type dopant may include Si, Ge, Sn, Se, or Te as an n-type dopant, but is not limited thereto. In one embodiment, the Al composition gradually decreases from the AlN template layer 111 to the active layer 114, thereby improving crystallinity.

[0131] A first conductivity type semiconductor layer 112b may be formed on the second superlattice layer 120b. The first conductivity type semiconductor layer 112b may be implemented as, for example, a III-V or II-VI group compound semiconductor. For example, the first conductivity type semiconductor layer 112b may be formed from any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. The first conductivity type semiconductor layer 112b may have a lower Al composition than the first semiconductor layer 112a, the second layer 121b, and the third layer 123a. The Al composition of the first conductivity type semiconductor layer 112b may be within the same range as the Al composition of the fourth layer 123b.

[0132] The first conductivity type semiconductor layer 112b of the embodiment may include having Al z Ga 1-z Semiconductor materials with an N (0.45 ≤ z ≤ 0.55) composition. The first conductivity type semiconductor layer 112b of the embodiment may include 45% to 55% Al composition, and the thickness of the first conductivity type semiconductor layer 112b of the embodiment may be 500 to 1000 nm. In one embodiment, a first conductivity type semiconductor layer 112b having a thickness of 1000 nm is described as an example. The first conductivity type semiconductor layer 112b may be doped with a first conductivity type dopant. When the first conductivity type dopant is an n-type dopant, the first conductivity type dopant may include Si, Ge, Sn, Se, or Te as an n-type dopant, but is not limited thereto.

[0133] Reference Figure 10 The active layer 114 can be disposed on the first conductivity type semiconductor layer 112b, and the EBL 130 can be disposed on the active layer 114. The active layer 114 and the EBL 130 can be formed by methods such as MOCVD, CVD, PECVD, MBE, HVPE, etc., but are not limited thereto.

[0134] The formation conditions of active layer 114 and EBL 130 can improve optical power and increase optical efficiency.

[0135] The active layer 114 can be formed as at least one of a single quantum well structure, a multiple quantum well (MQW) structure, a quantum wire structure, and a quantum dot structure. The active layer 114 is a layer through which electrons (or holes) injected through the first conductivity type semiconductor layer 112b encounter holes (or electrons) injected through the second conductivity type semiconductor layer 116a, and emits light by means of the band gap difference of the energy bands of the materials forming the active layer 114.

[0136] The active layer 114 may be made of a compound semiconductor. The active layer 114 may be implemented as at least one of, for example, group III-V or group II-VI compound semiconductors. The active layer 114 may include a quantum well layer and a quantum wall layer. When the active layer 114 is implemented using an MQW structure, the quantum well layer and the quantum wall layer may be alternately arranged. The quantum well layer and the quantum wall layer may be formed as any one or more pairs of AlGaN / GaN, AlGaN / AlGaN, InGaN / GaN, InGaN / InGaN, InAlGaN / GaN, GaAs / AlGaAs, InGaAs / AlGaAs, GaP / AlGaP, and InGaP / AlGaP, but are not limited thereto.

[0137] In one embodiment of the active layer 114, the thickness of each quantum well layer can be 10% to 25% of the thickness of each quantum wall layer. (Refer to...) Figure 6 By using a quantum well layer structure with a thickness of 10% to 25% of the thickness of the quantum wall layer, the active layer 114 in this embodiment can improve optical power. For example, each quantum well layer can be 1.5 to 2.5 nm. Figure 6 This is a graph showing the optical power of the quantum well layer 114 with a quantum wall layer of 10.9 nm thickness, and the highest optical power in the quantum well layer with a thickness of 2.1 nm is shown.

[0138] EBL 130 can be formed on active layer 114. EBL 130 may include a second dopant. The EBL 130 of an embodiment may include multiple barrier layers 131, 133, 135, and 137, and multiple well layers 132, 134, and 136. EBL 130 may be formed of a III-V or II-VI compound semiconductor; for example, EBL 130 may be formed of three or more pairs of AlGaN / AlGaN, but is not limited thereto. EBL 130 may be doped with a second conductivity type dopant. For example, when EBL 130 is a p-type semiconductor layer, the second conductivity type dopant may include Mg, Zn, Ca, Sr, or Ba as a p-type dopant. The EBL 130 of an embodiment may include functionality for increasing the number of charge carriers supplied to active layer 114 to achieve a 295-315 nm UVB driven by a high current of 100 mA or higher. Additionally, the EBL 130 can include an electron blocking function to block electrons, thus improving luminous efficiency. For this purpose, an embodiment of the EBL 130 can be formed including a dopant of a second conductivity type, such that multiple barrier layers 131, 133, 135, and 137 and multiple well layers 132, 134, and 136 are alternately arranged in three pairs. The multiple barrier layers 131, 133, 135, and 137 and the multiple well layers 132, 134, and 136 of the embodiment can improve luminous efficiency through Al composition and thickness.

[0139] Based on the energy level reference (REF) of the last quantum wall layer of active layer 114, some layers of EBL 130 may include high Al composition. For example, the last quantum wall layer of active layer 114 may include 50% Al composition, and the multiple barrier layers 131, 133, 135, and 137 may include at least 45% or more Al composition. Here, the multiple barrier layers 131, 133, 135, and 137 may include a higher Al composition than the multiple well layers 132, 134, and 136, and may include an Al composition higher than that of the last quantum wall layer of active layer 114. The Al composition of EBL 130 can block electrons and confine holes to improve luminescence efficiency by increasing carrier injection into active layer 114.

[0140] The plurality of barrier layers 131, 133, 135, and 137 may include a first barrier layer 131 in contact with the active layer 114, a second barrier layer 137 in contact with the first conductive semiconductor layer 116a, and a first intermediate barrier layer 133 and a second intermediate barrier layer 135 disposed between the first barrier layer 131 and the second barrier layer 137. Here, any one of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 may be omitted, or there may be three or more. The plurality of well layers 132, 134, and 136 may include a first well layer 132 between the first barrier layer 131 and the first intermediate barrier layer 133, a second well layer 134 between the first intermediate barrier layer 133 and the second intermediate barrier layer 135, and a third well layer 136 between the second intermediate barrier layer 135 and the second barrier layer 137.

[0141] The first barrier layer 131 may have a higher Al composition than the final quantum wall layer of the active layer 114. For example, the first barrier layer 131 may include Al... p Ga 1-p Semiconductor materials with an N (0.50 ≤ p ≤ 0.74) composition. The first barrier layer 131 in this embodiment may include 50% to 74% Al content, and the thickness W1 of the first barrier layer 131 in this embodiment may be greater than the thickness W2 of the first well layer 132. The thickness W1 of the first barrier layer 131 in this embodiment may be 3 to 10 nm.

[0142] The second barrier layer 137 may have a higher Al content than the first conductive semiconductor layer 116a. For example, the second barrier layer 137 may include layers with Al content... q Ga 1-qA semiconductor material with an N (0.50 ≤ q ≤ 0.74) composition. The second barrier layer 137 of the embodiment may include 50% to 74% Al content, and the thickness W7 of the second barrier layer 137 of the embodiment may be greater than the thickness W6 of the third well layer 136. The thickness W7 of the second barrier layer 137 of the embodiment may be 3 to 10 nm.

[0143] The first intermediate barrier layer 133 and the second intermediate barrier layer 135 may have a higher Al content than the first barrier layer 131 and the second barrier layer 137. The EBL 130 of the embodiment can improve hole injection. For example, the EBL 130 can improve luminous efficiency by confining holes in the first intermediate barrier layer 133 and the second intermediate barrier layer 135, thereby increasing carrier injection into the active layer 114. The first intermediate barrier layer 133 and the second intermediate barrier layer 135 may include Al... r Ga 1-r Semiconductor materials with an N (0.55 ≤ r ≤ 0.74) composition. The first intermediate barrier layer 133 and the second intermediate barrier layer 135 of the embodiment may contain 55% to 74% Al composition. The thicknesses W3 and W5 of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 of the embodiment may be thicker than the thickness W4 of the second well layer 134. The thicknesses W3 and W5 of the first intermediate barrier layer 133 and the second intermediate barrier layer 135 of the embodiment may be 3 to 10 nm. Specifically, when the EBL 130 includes a first barrier layer 131 and a second barrier layer 137 with 54% Al composition and a first intermediate barrier layer 133 and a second intermediate barrier layer 135 with 64% Al composition, the output voltage can be increased by 30% or more compared to conventional ultraviolet light-emitting devices.

[0144] The plurality of well layers 132, 134 and 136 may include: a first well layer 132 between a first barrier layer 131 and a first intermediate barrier layer 133, a second well layer 134 between a first intermediate barrier layer 133 and a second intermediate barrier layer 135, and a third well layer 136 between a second intermediate barrier layer 135 and a second barrier layer 137.

[0145] The first well layer 132 may include the last quantum wall layer 114a of the active layer 114 (see [link]). Figure 4 The first well layer 132 may include an Al composition with low Al content. e Ga 1-e Semiconductor materials with an N (0.24 ≤ e ≤ 0.45) composition. In this embodiment, the thickness W2 of the first well layer 132 can be thinner than the thickness W1 of the first barrier layer 131 and the thickness W3 of the first intermediate barrier layer 133. The thickness W2 of the first well layer 132 in this embodiment can be 1 to 5 nm.

[0146] The second well layer 134 may include an Al composition lower than that of the final quantum wall layer of the active layer 114. The second well layer 134 may include Al... f Ga 1-f Semiconductor materials with an N (0.24 ≤ f ≤ 0.48) composition. The thickness W4 of the second well layer 134 in this embodiment can be thinner than the thicknesses W3 and W5 of the first intermediate barrier layer 133 and the second intermediate barrier layer 135. The thickness W4 of the second well layer 134 in this embodiment can be 1 to 5 nm.

[0147] The third well layer 136 may include an Al composition lower than that of the last quantum wall layer of the active layer 114. The third well layer 136 may include Al... g Ga 1-g Semiconductor materials with an N (0.24 ≤ g ≤ 0.48) composition. The thickness W6 of the third well layer 136 in this embodiment can be thinner than the thickness W5 of the second intermediate barrier layer 135 and the thickness W7 of the second barrier layer 137. The thickness W6 of the third well layer 136 in this embodiment can be 1 to 5 nm. The second and third well layers 134 and 136 can have the same Al composition and thickness, but are not limited thereto.

[0148] In one embodiment, EBL 130 can be disposed on the active layer 114 to improve carrier injection efficiency, thereby improving luminescence efficiency. The embodiment can achieve 295 to 315 nm UVB driven by a high current of 100 mA or higher.

[0149] Reference Figure 11 The first conductive semiconductor layer 116a and the second conductive semiconductor layer 116b can be formed on the EBL 130. The first conductive semiconductor layer 116a and the second conductive semiconductor layer 116b can be formed by methods such as MOCVD, CVD, PECVD, MBE, HVPE, etc., but are not limited thereto.

[0150] The first conductive semiconductor layer 116a and the second conductive semiconductor layer 116b can be grown under pressure between the first conductivity type semiconductor layer 112b and the EBL 130. For example, the first conductive semiconductor layer 116a and the second conductive semiconductor layer 116b can be grown under a pressure of 450 millipards (mbar), but are not limited thereto.

[0151] A first conductive semiconductor layer 116a can be formed on EBL 130. The first conductive semiconductor layer 116a can be implemented as, for example, a III-V or II-VI group compound semiconductor. For example, the first conductive semiconductor layer 116a can be formed from any or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. The first conductive semiconductor layer 116a in the embodiment may include Al... s Ga 1-s A semiconductor material with an N (0.20 ≤ s ≤ 0.45) composition. The first conductive semiconductor layer 116a may include 20% to 45% Al composition. The thickness of the first conductive semiconductor layer 116a may be 40 nm or greater. Figure 7 This is a graph illustrating the reliability of the thickness of the first conductive semiconductor layer according to an embodiment. (Refer to...) Figure 7 When the first conductive semiconductor layer 116a in the embodiment has a thickness of 40 nm or greater, the output voltage changes constantly over time, thus improving reliability. The thickness of the first conductive semiconductor layer 116a in the embodiment can be from 40 to 300 nm. The first conductive semiconductor layer 116a can be doped with a second conductivity type dopant. In the case that the first conductive semiconductor layer 116a is a p-type semiconductor layer, the second conductivity type dopant can include Mg, Zn, Ca, Sr, or Ba as a p-type dopant.

[0152] The second conductive semiconductor layer 116b can be formed on the first conductive semiconductor layer 116a. The second conductive semiconductor layer 116b can be disposed on the first conductive semiconductor layer 116a and the second electrode 153 (see Figure 2 Between the first conductive semiconductor layer 116a and the second electrode 153, an ohmic contact is provided (see [reference]). Figure 2 The second conductive semiconductor layer 116b may be GaN including a first conductivity type dopant, for an ohmic contact between the first conductive semiconductor layer 116a and the second electrode 153 (see [link]). Figure 2 However, this is not the only possibility. The surface of the second conductive semiconductor layer 116b that is in direct contact with the second electrode 153 can be flat (see...). Figure 2 Therefore, the second conductive semiconductor layer 116b can be formed by a 2D growth method. Figure 8 This is a view showing the surface of the second conductive semiconductor layer of an embodiment. The second conductive semiconductor layer 116b of the embodiment can be achieved as a flat surface through 2D growth to improve the reliability of contact with the second electrode 153 (see [link]). Figure 2 ).

[0153] Reference Figure 12 The first electrode 151 and the second electrode 153 can be formed on the light-emitting structure 110. In the light-emitting structure 110, a portion of the first conductivity type semiconductor layer 112b can be exposed by mesa etching from the active layer 114, EBL 130, the first conductive semiconductor layer 116a and the second conductive semiconductor layer 116b.

[0154] The first electrode 151 may be formed on the exposed first conductivity type semiconductor layer 112b. The first electrode 151 may be electrically connected to the first conductivity type semiconductor layer 112b. The first electrode 151 may be electrically insulated from the second electrode 153.

[0155] The second electrode 153 can be formed on the second conductive semiconductor layer 116b. The second electrode 153 can be electrically connected to the second conductive semiconductor layer 116b.

[0156] The first electrode 151 and the second electrode 153 can be conductive oxides, conductive nitrides, or metals. For example, the first electrode 151 and the second electrode 153 can include at least one of indium tin oxide (ITO), ITO nitride (ITON), indium zinc oxide (IZO), IZO nitride (IZON), zinc aluminum oxide (AZO), zinc aluminum gallium oxide (AGZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), antimony tin oxide (ATO), zinc gallium oxide (GZO), IZO nitride (IZON), ZnO, IrOx, RuOx, NiO, Au, Cu, Ni, Ti, Ti-W, Cr, W, Pt, V, Fe, and Mo, and can be formed as a single layer or multiple layers.

[0157] Reference Figure 13 The embodiment can be a flip-chip structure, wherein the first electrode 151 and the second electrode 153 are disposed at the lower part. A first insulating layer 161 may expose a portion of the lower surface of the first electrode 151 and the second electrode 153 and is formed on the light-emitting structure 110. The first insulating layer 161 may contact the lower part of the light-emitting structure 110, wherein the first electrode 151 and the second electrode 153 are disposed.

[0158] The first connecting electrode 171 and the second connecting electrode 173 can be formed on the lower surfaces of the first electrode 151 and the second electrode 153 exposed from the first insulating layer 161. The first connecting electrode 171 and the second connecting electrode 173 can be formed by an electroplating process, but are not limited thereto. The first insulating layer 161 can be an oxide or a nitride. For example, the first insulating layer 161 can be selected from materials including SiO2 and Si... x O y Si3N4, Si x Ny SiO x N y At least one of the group consisting of Al2O3, TiO2, AlN, etc.

[0159] The first connecting electrode 171 and the second connecting electrode 173 can be at least one metal or an alloy thereof selected from Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au, and Hf. The first connecting electrode 171 and the second connecting electrode 173 can be formed as a single layer or multiple layers, including metals or alloys and transparent conductive materials such as ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, or ATO.

[0160] The second insulating layer 163 may be formed below and in direct contact with the first insulating layer 161. The second insulating layer 163 may expose the lower portions of the first connecting electrode 171 and the second connecting electrode 173, and may be formed on the sides of the first connecting electrode 171 and the second connecting electrode 173. The second insulating layer 163 may be formed by adding a thermal diffusing agent to a resin such as silicone or epoxy resin. The thermal diffusing agent may include at least one material selected from oxides, nitrides, fluorides, and sulfides, for example, ceramic materials having materials such as Al, Cr, Si, Ti, Zn, and Zr. The thermal diffusing agent may be defined as powder particles, grains, fillers, or additives having a predetermined size. The second insulating layer 163 may be omitted.

[0161] First pad 181 and second pad 183 may be formed on first connection electrode 171 and second connection electrode 173 exposed from second insulating layer 163. First pad 181 and second pad 183 may be at least one metal selected from Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au, and Hf, or an alloy thereof. First pad 181 and second pad 183 may be formed as a single layer or multiple layers, including metals or alloys and transparent conductive materials such as ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, or ATO.

[0162] One embodiment includes a substrate 101 disposed on a first conductivity type semiconductor layer 112b, but is not limited thereto. For example, the substrate 101 can be removed by a laser lift-off (LLO) process. Here, the LLO process is a process in which a laser is irradiated onto the lower surface of the substrate 101 to separate the substrate 101 and the light-emitting structure 110 from each other. In the light-emitting device 100 according to the embodiment, the substrate 101 and the AlN template layer 111 can be removed, but are not limited thereto.

[0163] The ultraviolet light-emitting device 100 of the embodiment may have a full width at half maximum (FWHM) of 17 nm or less. Typically, ultraviolet light-emitting devices with an FWHM of 20 nm or greater, at 300 nm or less, particularly 298 nm or less, damage DNA, proteins, etc., and are therefore difficult to apply in medical devices such as those using Atopy treatment. In one embodiment, each quantum well layer of the active layer 114 may include a thickness of 10% to 25% of the thickness of each quantum wall layer to achieve an FWHM of 17 nm or less, thereby improving the reliability of the ultraviolet light-emitting device for use in medical devices.

[0164] The active layer 114 and EBL 130 in the embodiment can improve optical power and increase optical efficiency.

[0165] In one embodiment, the EBL 130 is disposed on the active layer 114 to improve carrier injection efficiency, thereby enabling high current drive of 100 mA or higher. Specifically, in one embodiment, the first intermediate barrier layer 133 and the second intermediate barrier layer 135 can achieve a high current drive of 295 to 315 nm UVB of 100 mA or higher by means of an EBL 130 structure having a higher Al composition than the first barrier layer 131 and the second barrier layer 137.

[0166] In one embodiment, the first semiconductor layer 112a, the first superlattice layer 120a, the first conductivity type semiconductor layer 112b, and the second superlattice layer 120b may be included between the substrate 101 and the active layer 114 to improve defects, thereby improving luminous efficiency.

[0167] In one embodiment, optical power can be improved by including a quantum well layer with a thickness of 10% to 25% of the thickness of the quantum wall layer in the active layer 114.

[0168] In one embodiment, reliability can be improved by using a first conductive semiconductor layer 116a with a thickness of 40 nm or greater.

[0169] Figure 14 This is a plan view showing the package of a light-emitting device according to an embodiment.

[0170] like Figure 14 As shown, the light-emitting device package 200 of the embodiment may include a light-emitting device 100, a package body 201, a heat sink 210, a protection device 260, a first lead frame 220 and a second lead frame 230.

[0171] Package 201 may include at least one of a light-transmitting material, a reflective material, and an insulating material. For light emitted from the light-emitting device 100, package 201 may include a material with a reflectivity higher than its transmittance. Package 201 includes an insulating material such as a ceramic material. The ceramic material includes simultaneously co-fired low-temperature co-fired ceramic (LTCC) or high-temperature co-fired ceramic (HTCC). The material of package 201 may be, for example, AlN, and may be formed from a metal nitride having a thermal conductivity of 140 W / mK or higher. Package 201 may be a resin-based insulating material. For example, package 201 may be formed from at least one of polyphthalamide (PPA), epoxy resin or silicone resin materials, silicon (Si), metallic materials, photosensitive glass (PSG), sapphire (Al2O3), and resin materials used in printed circuit boards (PCBs). When viewed from above, package 201 may have, for example, a square shape, but is not limited thereto. The top view of package 201 may be circular or polygonal.

[0172] Package 201 can be connected to a first lead frame 220 and a second lead frame 230. Package 201 may include a cavity 203 exposing a portion of the upper surface of the first lead frame 220 and the second lead frame 230. Cavity 203 may be formed as a recess, wherein the upper portion of package 201 is recessed or recessed. Cavity 203 may expose a portion of the upper surface of the first lead frame 220 and may expose a portion of the upper surface of the second lead frame 230. The first lead frame 220 and the second lead frame 230 may be disposed at the bottom of cavity 203. The first lead frame 220 and the second lead frame 230 may be disposed spaced apart from each other at the bottom of cavity 203, and at least a portion thereof may extend into or to the bottom of package 201 through a through-hole structure. The first lead frame 220 may include a curved shape adjacent to and extending along at least two side surfaces of cavity 203. The second lead frame 230 includes a first lead portion 231a in which a light-emitting device 100 is disposed, a second lead portion 231b disposed outside the first lead portion 231a, and a third lead portion 231c. The top surface area of ​​the first lead portion 231a can be larger than the top surface area of ​​the first lead frame 220, thereby improving heat dissipation efficiency. The first lead portion 231a can be disposed between the second lead portion 231b and the first lead frame 220. The first lead portion 231a can be disposed at the bottom center of the cavity 203. The first lead portion 231a can be electrically connected to the light-emitting device 100 via a wire 100W2. Relative to the light-emitting device 100, the second lead portion 231b can be disposed on the opposite side of the first lead frame 220 and can have a curved shape along the other two side surfaces. At least one of the second lead portion 231b and the first lead frame 220 can be connected to the light-emitting device 100 via a wire.

[0173] The light-emitting device 100 according to the embodiment can be disposed at the bottom of the cavity 203. A protective device 260 for protecting the light-emitting device 100 can be disposed in the cavity 203.

[0174] The first lead portion 231a can be exposed in the central region of the cavity 203, the second lead portion 231b can be diagonally symmetrical with the first lead frame 220 to correspond to the shape of the first lead frame 220, and the third lead portion 231c can be disposed in the edge region and diagonal edge region of the cavity 203, wherein a protective device 260 is installed. The first to third lead portions 231a, 231b and 231c can be exposed at the bottom surface of the cavity 203, and the shape including the area and width of the upper surface of the second lead frame 230 can be varied.

[0175] The first lead frame 220 and the second lead frame 230 may be spaced apart from each other at a predetermined distance and connected to the package 201. A light-emitting device 100 according to an embodiment may be disposed on the second lead frame 230. A first wire 100W1 connected to the light-emitting device 100 may be connected in the first lead frame 220. A protective device 260 may be disposed on a third lead portion 231c of the second lead frame 230 and may be connected to the first lead frame 220 via a wire 260W. One or more third lead portions 231c may be provided and may be spaced apart from both ends of the first lead frame 220 at a predetermined distance. The third lead portion 231c may be disposed at a depth lower than the bottom of the cavity 203 to reduce optical loss when the protective device 260 is provided. The first lead frame 220 may have a diagonally bent structure symmetrical to the second lead portion 231b, but is not limited thereto.

[0176] The first lead frame 220 and the second lead frame 230 may include conductive materials. For example, the first lead frame 220 and the second lead frame 230 may include at least one of titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum (Ta), tin (Sn), silver (Ag), phosphorus (P), iron (Fe), tin (Sn), zinc (Zn), and aluminum (Al), and may be formed of multiple layers. For example, the first lead frame 220 and the second lead frame 230 of the embodiment may be composed of a base layer including copper (Cu) and an anti-oxidation layer including silver (Ag) covering the base layer, but are not limited thereto.

[0177] The heat sink 210 may include a first lead electrode 211 and a second lead electrode 213. The first lead electrode 211 may include a first pad portion 211a connected to a first wire 100W1, and the second lead electrode 213 may include a second pad portion 213a connected to a second wire 100W2. In the heat sink 210, the first lead electrode 211 and the second lead electrode 213 are disposed on a ceramic body or an insulating material body, and a light-emitting device 100 according to an embodiment is disposed on the first lead electrode 211 and the second lead electrode 213. The light-emitting device 100 may be flip-chip bonded to the first lead electrode 211 and the second lead electrode 213, or may be connected by one or more wires. The area of ​​the first lead electrode 211 and the second lead electrode 213 may be larger than the area of ​​the light-emitting device 100 on the body of the heat sink 210 to improve heat dissipation efficiency and conduct heat via the package 201. The heat sink 210 may be adhered to the bottom of the cavity 203 with an adhesive, but is not limited thereto.

[0178] The light-emitting device 100 can be mounted on the heat sink 210. The light-emitting device 100 may include... Figures 1 to 13 Technical features.

[0179] The protection device 260 may be disposed on the third lead portion 231c. The protection device 260 may be disposed on the upper surface of the second lead frame 230 exposed from the package 201. The protection device 260 may be a Zener diode, a thyristor, a transient voltage suppressor (TVS), etc., but is not limited thereto. The protection device 260 of the embodiment will be described as a Zener diode protecting the light-emitting device 100 from electrostatic discharge (ESD). The protection device 260 may be connected to the first lead frame 220 via a wire.

[0180] Figure 15 It is shown that according to the embodiment, it has Figure 1 Light-emitting devices or Figure 14 A perspective view of the light-emitting module packaged with a light-emitting device. Figure 16 It is shown Figure 15 A plan view of the light-emitting unit of the light-emitting module, and Figure 17 This is a diagram illustrating the light uniformity of the light-emitting module in an embodiment.

[0181] like Figure 15 and Figure 16 As shown, the light-emitting module 10 of the embodiment may include a light-emitting unit 20, a first heat-dissipating component 30, and a second heat-dissipating component 40. One embodiment limits the configuration of the first heat-dissipating component 30 and the second heat-dissipating component 40, but is not limited thereto. One embodiment requires a highly reliable light-emitting module 10 for medical treatment with efficient UVB wavelengths. Additionally, as... Figure 17As shown, a light-emitting module 10 is needed that can achieve light uniformity of 70% or higher in the target region TA, while reducing the number of light-emitting device packages 200, thereby reducing the overall size and manufacturing cost. To this end, embodiments can have a high current drive of 200mA or higher and a full width at half maximum (FWHM) of 17nm or less, and the light emitted from the light-emitting unit 20 can have a uniformity of 70% or higher in the target region TA. Here, uniformity can be defined as minimum illuminance (Min) / maximum illuminance (Max) relative to the central region where illuminance is maximized and the edge region where illuminance is minimized in the target region.

[0182] like Figure 15 and Figure 16 As shown, the first heat dissipation component 30 can be disposed on the rear surface of the light-emitting unit 20. The first heat dissipation component 30 can be in direct contact with the light-emitting unit 20 and can dissipate heat generated from the light-emitting unit. The first heat dissipation component 30 can be, for example, a heat sink, but is not limited thereto. The first heat dissipation component 30 can include multiple heat dissipation fins. Here, multiple heat dissipation fins can increase the heat dissipation area to improve heat dissipation efficiency.

[0183] The second heat dissipation component 40 may be disposed on the rear surface of the first heat dissipation component 30. The second heat dissipation component 40 may be in direct contact with the first heat dissipation component 30. The second heat dissipation component 40 may include a function to dissipate the heat transferred at the first heat dissipation component 30 to the outside. For example, the second heat dissipation component 40 may include a cooling fan using air convection, but is not limited thereto.

[0184] The light-emitting unit 20 of the embodiment may include a circuit board 21 and multiple light-emitting device packages 200. The multiple light-emitting device packages 200 may be mounted on the front surface of the circuit board 21. Here, the circuit board 21 may contact the first heat dissipation component 30 at its rear surface. In the dimensions of the circuit board 21, the length C1 in the first direction may be the same as or different from the length C2 in the second direction. The lengths C1 and C2 of the circuit board 21 may be four or five times the length 200W of the light-emitting device packages 200. The circuit board 21 may include a resin-based printed circuit board (PCB), a metal-core PCB, a flexible PCB, a ceramic PCB, and an FR-4 substrate.

[0185] Multiple light-emitting device packages 200 can emit UVB wavelengths of 300 to 320 nm, driven by a high current of 100 mA or higher. Specifically, multiple light-emitting device packages 200 can achieve an effective wavelength with a full width at half maximum (FWHM) of 17 nm or less for optical therapy (300 to 320 nm). Typically, UV light-emitting devices with an FWHM of 20 nm or greater at 300 nm or less, particularly 298 nm or less, damage DNA, proteins, etc., and are therefore difficult to apply in medical devices such as those used for atopy treatment. The light-emitting device package 200 of the embodiment can achieve a full width at half maximum (FWHM) of 17 nm or less to improve the reliability of the light-emitting module 10 for optical therapy.

[0186] like Figure 16 and Figure 17 As shown, the light-emitting module 10 of the embodiment can achieve 70% or higher light uniformity in the target region TA, projecting ultraviolet wavelength light emitted from the light-emitting device package 200 into the target region TA. Light uniformity can be defined as minimum illuminance (Min) / maximum illuminance (Max) relative to the central region where illuminance is maximized and the edge region where illuminance is minimized in the target region TA. For example, the target region TA may be spaced 20 mm from the light-emitting unit 20 of the light-emitting module 10 and have a width Y1 and width X1 of 30 mm, but is not limited thereto. The target region TA may have a width Y1 and width X1 of 10 to 30 mm. Specifically, the target region TA for phototherapy can have 70% or higher uniformity, defined as minimum illuminance (Min) / maximum illuminance (Max) and 10 mW / cm². 2 Or a larger minimum illuminance. When light uniformity is less than 70%, the reliability of phototherapy may deteriorate due to the irradiation difference between the central and peripheral regions of the target area (TA).

[0187] Multiple light-emitting device packages 200 may have a first spacing P1 in a first direction X-X' and a second spacing P2 in a second direction Y-Y' orthogonal to the first direction X-X'. The first spacing P1 and the second spacing P2 may be 30% to 50% of the width Y1 and width X1 of the target region TA. The first spacing P1 and the second spacing P2 may be 10 mm or greater. The first spacing P1 and the second spacing P2 may be 10 to 15 mm. The first spacing P1 and the second spacing P2 may be the same, but are not limited thereto. For example, the first spacing P1 and the second spacing P2 may be different from each other. For example, an embodiment may include 25 light-emitting device packages 200 having a first spacing P1 and a second spacing P2 of 10 mm to achieve 70% or higher uniformity in a target region TA spaced 20 mm apart and having a width Y1 and a width X1 of 30 mm. Here, each light-emitting device package 200 may have a luminous intensity Po of 10 mW or greater. (See reference...) Figures 6 to 19 Detailed description of the light-emitting device package 200.

[0188] By achieving uniformity in providing 70% or more of the ultraviolet wavelength to the target area, the embodiment can improve the reliability of the light-emitting module 10 used for phototherapy.

[0189] By achieving an effective wavelength (300 to 320 nm) of ultraviolet light driven by a high current of 200 mA or higher for optical therapy, the embodiments can improve the reliability of the light-emitting module 10 for optical therapy.

[0190] Examples may provide light-emitting modules and medical devices capable of improving the reliability of therapeutic ultraviolet wavelengths with a full width at half maximum (FWHM) of 17 nm or less.

[0191] In one embodiment, in a plurality of light-emitting device packages 200 having light uniformity of 70% or higher and a spacing of 30% to 50% between the widths Y1 and X1 of the target region TA, the total number of light-emitting device packages 200 can be reduced, thereby reducing the size of the light-emitting module 10 and thus reducing manufacturing costs.

[0192] Figure 18 This is a cross-sectional view of a medical device with a light-emitting module, as another embodiment. Figure 19 This is a diagram illustrating the light uniformity of a light-emitting module according to another embodiment.

[0193] like Figure 16 , Figure 18 and Figure 19As shown, the medical device 70, including the light-emitting module 10, can have 70% or higher uniformity of light emitted from the light-emitting unit 20 in the circular target area TA. Here, in another embodiment, the minimum illuminance of the edge region of the light-emitting module is constant, so that the other embodiment can have a higher uniformity than... Figure 16 and Figure 17 The light-emitting module in this embodiment exhibits higher uniformity. Here, Figure 17 In one embodiment, the minimum illuminance of the light-emitting module locally appears in the edge region of the rectangular target area. Therefore, the light-emitting module of another embodiment can improve the uniformity and reliability of the target area TA. The configuration of the light-emitting unit 20 and the first heat dissipation component 30 and the second heat dissipation component 40 of another embodiment can be adopted... Figures 17 to 19 Technical features of the light-emitting module 20.

[0194] Medical device 70 is a UV lamp that requires a highly reliable light-emitting module with efficient UVB wavelengths for medical treatment. Additionally, in another embodiment, a target area with 70% or higher uniformity is required, and the number of light-emitting device packages included in the light-emitting module should be reduced to decrease the size of medical device 70 and lower manufacturing costs. To this end, embodiments may have a high current drive of 200 mA or higher and a full width at half maximum (FWHM) of 17 nm or less, and the light emitted from the light-emitting unit 20 can have 70% or higher uniformity in the circular target area TA. Here, uniformity can be defined as minimum illuminance (Min) / maximum illuminance (Max) relative to the central region where illuminance is maximized and the edge regions where illuminance is minimized in the target area.

[0195] The medical device 70 may include an optical compensator 60. The optical compensator 60 may be disposed on the light-emitting unit 20. The optical compensator 60 may be disposed in the light output area of ​​the medical device 70. The optical compensator 60 may include first to third compensators 61, 63, and 65. The first compensator 61 may be disposed on the second compensator 63. The first compensator 61 may include a function for diffusing light. The first compensator 61 may include, but is not limited to, Teflon. The first compensator 61 may be made of a material with high light transmittance and excellent moisture resistance.

[0196] The second compensator 63 can be disposed below the first compensator 61 and on the light-emitting unit 20. Light emitted from the light-emitting unit 20 can directly illuminate the second compensator 63. The second compensator 63 may include a material with excellent light transmittance. Additionally, the second compensator 63 may include a function for diffused light. For example, the second compensator 63 may include a glass material. The second compensator 63 may be formed of, for example, a transparent material, such as LiF, MgF2, CaF2, BaF2, Al2O3, SiO2, or optical glass (N-BK7). SiO2 may be tetragonal or ultraviolet fused silica. Furthermore, the second compensator 63 may be low-iron glass.

[0197] The third compensator 65 may include the function of surrounding and extending the outer edges of the first compensator 61 and the second compensator 63. The third compensator 65 may include the function of diffusing light in a ring shape. The first compensator 61 and the second compensator 63 may be disposed within the opening region 65a of the third compensator 65. That is, the third compensator 65 may be connected to the circumference of the first compensator 61 and the second compensator 63. The area or width in the first direction of the second compensator 63 may be wider than the area or width in the first direction of the first compensator 61.

[0198] In another embodiment, an optical compensator 60, including first to third compensators 61, 63 and 65, may be disposed on the light-emitting module to diffuse the light emitted from the light-emitting unit 20 to the target area TA, thereby improving uniformity.

[0199] The optical compensator 60 can be connected to the upper opening region 69a of the housing 69, and at least a portion thereof can protrude. The housing 69 may contain internal supports 67 and 68, and may include a lower support 68 for supporting the exterior of the light-emitting unit 20 and an upper support 67 for reflecting light from above. The upper support 67 can be disposed below and outside the third compensator 65 of the optical compensator 60, such that the third compensator 65 is in close contact with the housing 69. Here, the top view of the light-emitting unit 20 can have the following characteristics: Figure 16 The shape of the inner holes of the circular or polygonal inner supports 67 and 68 may vary depending on the shape.

[0200] The light-emitting unit 20 includes multiple light-emitting device packages 200. The multiple light-emitting device packages 200 can emit UVB wavelengths from 300 to 320 nm. The multiple light-emitting device packages 200 can have various wavelengths from 300 to 320 nm. The multiple light-emitting device packages 200 can selectively use various wavelengths for optical therapy and experiments. For this purpose, the multiple light-emitting device packages 200 can have at least two different wavelengths. For example, a portion of the light-emitting device package 200 can emit wavelengths from 300 to 315 nm, and another portion of the light-emitting device package can emit wavelengths from 315 to 320 nm. The multiple light-emitting device packages 200 can emit UVB wavelengths from 300 to 320 nm, driven by a high current of 100 mA or higher. Specifically, the multiple light-emitting device packages 200 can achieve an effective wavelength with a full width at half maximum (FWHM) of 17 nm or less for optical therapy (300 to 320 nm). Typically, 20nm or larger FWHM ultraviolet light-emitting devices, especially 298nm or smaller, damage DNA, proteins, etc., making them difficult to apply in medical devices such as those using Atopy processing. The light-emitting device package 200 of the embodiment can achieve a full width at half maximum (FWHM) of 17nm or smaller to improve the reliability of the light-emitting module 10 for optical therapy.

[0201] like Figure 19 As shown, in another embodiment, the light-emitting module can achieve 70% or higher uniformity in the circular target region TA, where ultraviolet wavelength emitted light is transmitted to the circular target region TA. Light uniformity can be defined as minimum illuminance (Min) / maximum illuminance (Max), relative to the central region where illuminance is maximized and the edge region where illuminance is minimized in the circular target region TA. For example, the circular target region TA can be spaced 20 mm from the light-emitting unit 20 of the light-emitting module 10 and has a diameter Y2 of 30 mm, but is not limited thereto. The circular target region TA can have a diameter Y2 of 10 to 40 mm. Specifically, the circular target region TA for phototherapy can have 70% or higher uniformity, defined as minimum illuminance (Min) / maximum illuminance (Max), and has a uniformity of 10 mW / cm². 2 Or a larger minimum illuminance.

[0202] When the uniformity is less than 70%, the reliability of optical therapy may deteriorate due to the difference in irradiation between the central and peripheral regions of the circular target area (TA).

[0203] Reference Figure 16Multiple light-emitting device packages 200 may have a first spacing P1 in a first direction X-X' and a second spacing P2 in a second direction Y-Y' orthogonal to the first direction X-X'. The first spacing P1 and the second spacing P2 may be 30% to 50% of the diameter Y2 of the circular target region TA. The first spacing P1 and the second spacing P2 may be 10 mm or greater. The first spacing P1 and the second spacing P2 may be 10 to 15 mm. The first spacing P1 and the second spacing P2 may be the same, but are not limited thereto. For example, the first spacing P1 and the second spacing P2 may be different from each other. For example, an embodiment may include 25 light-emitting device packages 200 having a first spacing P1 and a second spacing P2 of 10 mm to achieve 70% or higher uniformity in a circular target region TA with a diameter Y2 of 30 mm and spaced 20 mm from the medical device 70. Here, each light-emitting device package 200 may have a luminous intensity Po of 10 mW or greater.

[0204] Another embodiment can improve the reliability of the medical device 70 for optical therapy by achieving a uniformity of 70% or higher in the ultraviolet wavelength provided at the target region TA.

[0205] Another embodiment can improve the reliability of the medical device 70 for optical therapy by achieving a high current drive of 200mA or higher with an effective wavelength (300 to 320nm) for optical therapy.

[0206] Another embodiment may provide a medical device 70 that can improve the reliability of therapeutic ultraviolet wavelengths with a full width at half maximum (FWHM) of 17 nm or less.

[0207] In another embodiment, in a plurality of light-emitting device packages 200 having a light uniformity of 70% or higher and a spacing of 30% to 50% of the diameter Y2 of the circular target region TA, the total number of light-emitting device packages 200 can be reduced, allowing for a smaller size of the light-emitting module and thus reducing manufacturing costs. Therefore, another embodiment can reduce the size and manufacturing cost of the medical device 70.

[0208] According to the embodiment, the light-emitting device, the package and the light-emitting module having the light-emitting device can be applied to medical devices, lighting units, indicator devices, lamps, streetlights, vehicle lighting devices, vehicle display devices, smartwatches, etc., but are not limited thereto.

[0209] The features, structures, and effects described in the above embodiments are included in at least one embodiment, but are not limited to one embodiment. Furthermore, those skilled in the art can combine or modify the features, structures, and effects shown in each embodiment for other embodiments. Therefore, it should be understood that anything relating to such combinations and modifications is included within the scope of this invention.

[0210] The foregoing primarily describes embodiments. However, these are merely examples and do not limit the invention. Those skilled in the art will understand that several variations and applications not presented above can be made without departing from the essential features of the embodiments. For example, each component specifically represented in the embodiments can be changed. Furthermore, it should be understood that differences associated with such variations and applications are included within the scope of the invention as defined in the following claims.

[0211] Industrial applicability

[0212] The ultraviolet light-emitting device according to the present invention can be used in various medical and therapeutic fields.

[0213] The UVB light-emitting device according to the present invention can be used in medical devices.

[0214] The light-emitting device according to the present invention can be used in biomedical optical therapy devices.

Claims

1. A light-emitting device, comprising: First conductivity type semiconductor layer; An active layer is disposed on the first conductivity type semiconductor layer; An electron blocking layer is disposed on the active layer; as well as A second conductivity type semiconductor layer is disposed on the electron blocking layer. The electron blocking layer comprises multiple barrier layers and multiple well layers. Each barrier layer includes a first barrier layer adjacent to the active layer, a second barrier layer adjacent to the second conductivity type semiconductor layer, and at least one intermediate barrier layer between the first and second barrier layers. The aluminum composition of the intermediate barrier layer is higher than that of the first and second barrier layers. The active layer includes a quantum well layer and a quantum wall layer. Each of the plurality of barrier layers has an aluminum composition higher than that of the quantum wall layer of the active layer. The well layer has an aluminum composition lower than that of the last quantum wall layer of the active layer. The aluminum composition of the last quantum wall layer of the active layer is higher than that of the second conductivity type semiconductor layer. The last quantum wall layer of the active layer is the quantum wall layer closest to the electron blocking layer among all the quantum wall layers of the active layer.

2. The light-emitting device according to claim 1, wherein, The thickness of the well layer is thinner than the thickness of the barrier layer.

3. The light-emitting device according to claim 1, wherein, The first barrier layer has Al p Ga 1-p N, where 0.50≤p≤0.74 is the constituent formula. The second barrier layer has Al q Ga 1-q N, where 0.50≤q≤0.74 is the composition formula, and The intermediate barrier layer has Al r Ga 1-r N, where 0.55≤r≤0.74 is the composition formula.

4. The light-emitting device according to claim 1, wherein, The plurality of well layers include a first well layer disposed between the first barrier layer and the intermediate barrier layer, a second well layer disposed between the plurality of intermediate barrier layers, and a third well layer disposed between the intermediate barrier layer and the second barrier layer.

5. The light-emitting device according to claim 4, wherein, The first well layer has the composition AleGa1-eN, where 0.24≤e≤0.

45.

6. The light-emitting device according to claim 4, wherein, The band gap of the first well layer is smaller than the band gap of the second well layer and / or the band gap of the third well layer.

7. The light-emitting device according to claim 4, wherein, The thickness of at least one of the first well layer, the second well layer, and the third well layer is 5 nm or less.

8. The light-emitting device according to claim 4, wherein, The Al composition of the second well layer and the third well layer is higher than that of the first well layer.

9. The light-emitting device according to claim 4, wherein, The second well layer has Al f Ga 1-f N, where 0.24≤f≤0.48 is the constituent formula. The third well layer has Al g Ga 1-g N, where 0.24≤g≤0.48 is the composition formula.

10. The light-emitting device according to claim 1, wherein, Each of the first barrier layer, the second barrier layer, and the intermediate barrier layer is thicker than the well layer and has a thickness of 3 nm to 10 nm.

11. The light-emitting device according to any one of claims 1-10, wherein, The light-emitting device further includes: An AlN template layer located beneath the semiconductor layer of the first conductivity type; A first superlattice layer, a first semiconductor layer, and a second superlattice layer are arranged sequentially between the first conductivity type semiconductor layer and the AlN template layer along the direction from the AlN template layer to the first conductivity type semiconductor layer; In the first superlattice layer, the first semiconductor layer, the second superlattice layer, and the first conductivity type semiconductor layer, the aluminum composition decreases along the direction close to the active layer.

12. The light-emitting device according to claim 11, wherein, The first conductivity type semiconductor layer includes an N-type dopant; The first superlattice layer comprises a first layer having an AlN semiconductor and a second layer having an AlGaN-based semiconductor; The concentration of dopants in the first and second layers is lower than the concentration of dopants added to the first conductivity type semiconductor layer.

13. The light-emitting device according to claim 11, wherein, The second superlattice layer includes a third layer having an AlGaN-based semiconductor and a fourth layer having an AlGaN-based semiconductor. The third and fourth layers are doped with dopants of a first conductivity type; The aluminum content of the fourth layer is more than 5% lower than that of the third layer.

14. The light-emitting device according to claim 11, wherein, The second superlattice layer includes a third layer having an AlGaN-based semiconductor and a fourth layer having an AlGaN-based semiconductor. The second superlattice layer is in contact with the first conductive semiconductor layer, and the aluminum composition of the first conductive semiconductor layer is the same as or lower than that of the fourth layer.

15. The light-emitting device according to claim 8, wherein, The thickness of the quantum well layer is less than 25% of the thickness of the quantum wall layer.

16. The light-emitting device according to any one of claims 1-10, wherein, The active layer emits ultraviolet light with a wavelength of 295 nm to 315 nm.

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