Semiconductor device and semiconductor device package including the same

Abstract

An embodiment of the present application discloses a semiconductor device and a semiconductor device package including the same. The semiconductor device includes: a semiconductor structure, including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer arranged between the first conductive semiconductor layer and the second conductive semiconductor layer; wherein the active layer includes a plurality of barrier layers and well layers, the barrier layers, the well layers, the first conductive semiconductor layer, and the second conductive semiconductor layer include aluminum, and the second conductive semiconductor layer includes a semiconductor layer whose aluminum composition decreases with a slope as it moves away from the active layer.

Description

[0001] This application is a divisional application of an invention patent application with an application date of September 1, 2017, application number 201710780660.X, and invention name “Semiconductor device and semiconductor device package including the same”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to Korean Patent Application No. 10-2016-0112809 filed in Korea on September 1, 2016 and Korean Patent Application No. 10-2016-0163830 filed in Korea on December 2, 2016, which are hereby incorporated by reference in their entirety. Technical Field

[0004] Embodiments relate to a semiconductor device and a semiconductor device package including the same. Background Art

[0005] Semiconductor devices including compounds such as GaN, AlGaN, etc. have many advantages, for example, have a wide and easily adjustable band gap energy, and therefore can be variously used as light-emitting devices, light-receiving elements, various diodes, and the like.

[0006] In particular, light-emitting devices such as light-emitting diodes and laser diodes using Group 3-5 or Group 2-6 compound semiconductor materials can achieve various colors such as red, green, blue and ultraviolet due to the development of thin film growth technology and device materials. Effective white light can be achieved by using fluorescent materials or combined colors. Compared with existing light sources such as fluorescent lamps and incandescent lamps, they have the advantages of low power consumption, semi-permanent life, fast response speed, safety, and environmental protection.

[0007] In addition, when using 3-5 group or 2-6 group compound semiconductor materials to manufacture photodetectors or light-receiving elements such as solar cells, light of various wavelength ranges can be absorbed to generate photocurrent by developing device materials, so that light of various wavelength ranges from gamma rays to radio wavelength regions can be used. In addition, it has the advantages of fast response speed, safety, environmental protection, and easy control of device materials, so it can be conveniently used in power supply control or ultra-high frequency circuits or communication modules.

[0008] Therefore, the application scope of semiconductor devices has been expanded to transmission modules of optical communication devices, LED backlights that replace cold cathode fluorescent lamps (CCFL) that constitute the backlight source of liquid crystal displays (LCDs), white LED lighting devices that can replace fluorescent lamps or incandescent bulbs, car headlights, traffic lights, and sensors for detecting gas or fire, etc. In addition, the application scope of semiconductor devices can be expanded to high-frequency application circuits or other power control devices, communication modules.

[0009] In particular, a light-emitting element that emits light in the ultraviolet wavelength region has a curing effect or a sterilizing effect, and therefore can be used for curing, medical treatment, sterilization, and the like.

[0010] In recent years, research on ultraviolet light emitting elements has been active, but ultraviolet light emitting elements still have problems such as being difficult to realize as vertical elements and having a problem of crystallinity degradation during the process of separating the substrates. Summary of the invention

[0011] Technical issues

[0012] The embodiment provides a vertical ultraviolet light emitting element and also provides a light emitting element with improved light output.

[0013] The problems to be solved by the present invention are not limited to the above-mentioned contents, but can be regarded as including the purposes or effects clearly understood from the solutions and embodiments to solve the problems described below.

[0014] Solutions to the problem

[0015] A semiconductor device according to an embodiment of the present invention may include: a semiconductor structure including a first conductive semiconductor layer, a second conductive semiconductor layer and an active layer arranged between the first conductive semiconductor layer and the second conductive semiconductor layer, wherein the active layer includes a plurality of barrier layers and well layers, the second conductive semiconductor layer includes a 2-2 conductive semiconductor layer and a 2-1 conductive semiconductor layer arranged on the 2-2 conductive semiconductor layer, the barrier layer, the well layer, the 2-2 conductive semiconductor layer and the 2-1 conductive semiconductor layer include AlGaN, the aluminum composition of the 2-2 conductive semiconductor layer is higher than the aluminum composition of the well layer, and the aluminum composition of the 2-1 conductive semiconductor layer is lower than the aluminum composition of the well layer.

[0016] Effects of the Invention

[0017] According to the embodiment, a vertical type ultraviolet light emitting element can be manufactured.

[0018] Furthermore, light absorption is suppressed in the semiconductor device, so that light output can be improved.

[0019] Furthermore, the absence of the GaN thin film can also reduce the contact resistance between the second conductive semiconductor layer and the second electrode.

[0020] Various advantages and effects of the present invention are not limited to the above contents and can be more easily understood in the process of describing the specific embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a conceptual diagram of a semiconductor structure according to a first embodiment of the present invention.

[0022] Figure 2 FIG. 4 is a graph showing the aluminum composition of the semiconductor structure according to the first embodiment of the present invention.

[0023] Figure 3a is a conceptual diagram of a semiconductor structure according to a second embodiment of the present invention.

[0024] Figure 3b FIG. 4 is a graph showing the aluminum composition of a semiconductor structure according to a second embodiment of the present invention.

[0025] Figure 4 is a conceptual diagram of a semiconductor device according to a first embodiment of the present invention.

[0026] Figure 5 is a conceptual diagram of a semiconductor device according to a second embodiment of the present invention.

[0027] Figure 6a and Figure 6b is a plan view of a semiconductor device according to an embodiment of the present invention.

[0028] Figure 7 A conceptual diagram of a semiconductor structure grown on a substrate.

[0029] Figure 8 A diagram for explaining a process of separating a substrate.

[0030] Fig. 9 FIG. 1 is a diagram for explaining a process of etching a semiconductor structure.

[0031] Fig.10 2 is a diagram showing a manufactured semiconductor device.

[0032] Fig.11 is a conceptual diagram of a semiconductor structure according to a third embodiment of the present invention.

[0033] Fig.12 FIG. 4 is a graph showing the aluminum composition of a semiconductor structure according to a third embodiment of the present invention.

[0034] Fig.13FIG. 4 is a secondary ion mass spectrometry (SIM) chart showing the change in aluminum intensity of a semiconductor structure according to a third embodiment of the present invention.

[0035] Fig.14 for Fig.13 A partial enlarged view of .

[0036] Fig.15 is a photograph of a semiconductor structure according to a third embodiment of the present invention.

[0037] Fig.16 for Figure 1 Conceptual diagram of the second conductive semiconductor layer.

[0038] Fig.17 The figure shows AFM data obtained by measuring the surface of the second conductive semiconductor layer according to the third embodiment of the present invention.

[0039] Fig.18 The AFM data is obtained by measuring the surface of a GaN thin film.

[0040] Fig.19 These are AFM data obtained by measuring the surface of a rapidly growing P-AlGaN layer.

[0041] Fig. 20 is a conceptual diagram of a semiconductor device according to a third embodiment of the present invention.

[0042] Fig.21a for Fig. 20 Floor plan.

[0043] Figure 21b for Fig. 20 Magnified view of part A.

[0044] Fig. 22 A plan view illustrating an interface between the second conductive type semiconductor layer and the second electrode.

[0045] Fig.23 FIG. 4 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention.

[0046] Fig.24 FIG. 4 is a plan view of a semiconductor device package according to an embodiment of the present invention.

[0047] Fig.25 for Fig.24 A variation of . DETAILED DESCRIPTION

[0048] This embodiment may be changed in other forms, or various embodiments may be combined with each other, but the scope of the present invention is not limited to the various embodiments described below.

[0049] Even if the contents described in a specific embodiment are not described in other embodiments, unless there is another description in the other embodiments that is contrary to or inconsistent with the above contents, it can be understood as the contents related to the other embodiments.

[0050] For example, if features related to constitution A are described in a specific embodiment, and features related to constitution B are described in other embodiments, even if there is no explicit record of an embodiment in which constitution A and constitution B are combined, it should be understood that they fall within the scope of the invention of the present invention unless there is otherwise contrary or inconsistent description.

[0051] In the description of the embodiments, it is understood that when any component is referred to as being “on” or “under” another component, it may be “directly” or “indirectly” on the other component, or one or more intervening layers may also be present. or It includes not only the upper side but also the lower side based on a component.

[0052] Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail to an extent that can be easily implemented by a person skilled in the art to which the present invention belongs.

[0053] The semiconductor structure according to an embodiment of the present invention can output light in an ultraviolet wavelength band. Exemplarily, the semiconductor structure can output light in a near ultraviolet wavelength band (UV-A), light in a far ultraviolet wavelength band (UV-B), or light in a deep ultraviolet wavelength band (UV-C). The wavelength range can be determined according to the composition ratio of Al in the semiconductor structure.

[0054] Exemplarily, the light of the near ultraviolet wavelength band (UV-A) may have a wavelength in the range of 320 nm to 420 nm, the light of the far ultraviolet wavelength band (UV-B) may have a wavelength in the range of 280 nm to 320 nm, and the light of the deep ultraviolet wavelength band (UV-C) may have a wavelength in the range of 100 nm to 280 nm.

[0055] Figure 1 is a conceptual diagram of a semiconductor structure according to a first embodiment of the present invention, Figure 2 FIG. 4 is a graph showing the aluminum composition of the semiconductor structure according to the first embodiment of the present invention.

[0056] Reference Figure 1 , the semiconductor device according to the embodiment includes a semiconductor structure 120A, wherein the semiconductor structure 120A includes a first conductive type semiconductor layer 124 , a second conductive type semiconductor layer 127 , and an active layer 126 disposed between the first conductive type semiconductor layer 124 and the second conductive type semiconductor layer 127 .

[0057] The first conductive type semiconductor layer 124 may be formed of a compound semiconductor such as a group III-V or group II-VI, and may be doped with a first dopant. x1 Al y1 Ga 1-x1-y1 N(0≤x1≤1, 0≤y1≤1, 0≤x1+y1≤1), for example, it can be selected from GaN, AlGaN, InGaN, InAlGaN, etc. Moreover, the first dopant can be an n-type dopant such as Si, Ge, Sn, Se, Te, etc. If the first dopant is an n-type dopant, the first conductive semiconductor layer 124 doped with the first dopant can be an n-type semiconductor layer.

[0058] The active layer 126 is disposed between the first conductive type semiconductor layer 124 and the second conductive type semiconductor layer 127. The active layer 126 is a layer where electrons (or holes) injected through the first conductive type semiconductor layer 124 and holes (or electrons) injected through the second conductive type semiconductor layer 127 meet. When the electrons and holes are recombined, the active layer 126 is transformed from a high energy level to a low energy level, so that light having an ultraviolet wavelength can be generated.

[0059] The active layer 126 may have any of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, or a quantum wire structure, but the structure of the active layer 126 is not limited thereto. In addition, the active layer 126 may include a well layer 126b and a barrier layer 126a, and the energy band gap of the barrier layer 126a may be greater than the energy band gap of the well layer 126b.

[0060] The second conductive semiconductor layer 127 is formed on the active layer 126 and can be implemented by compound semiconductors of group III-V, group II-VI, etc. The second conductive semiconductor layer 127 can be doped with a second dopant. x5 Al y2 Ga 1-x5-y2 N(0≤x5≤1, 0≤y2≤1, 0≤x5+y2≤1) or a material selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP. If the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, Ba, etc., the second conductive semiconductor layer 127 doped with the second dopant can be a p-type semiconductor layer.

[0061] The second conductive type semiconductor layer 127 may include a 2-1 conductive type semiconductor layer 127 a having a relatively low aluminum composition and a 2-2 conductive type semiconductor layer 127 b having a relatively high aluminum composition.

[0062] The barrier layer 129 may be disposed between the active layer 126 and the second conductive semiconductor layer 127. The barrier layer 129 blocks the flow of the first carrier supplied from the first conductive semiconductor layer 124 to the active layer 126 from leaking to the second conductive semiconductor layer 127, so as to increase the probability of the first carrier and the second carrier being recombined in the active layer 126. The energy band gap of the barrier layer 129 may be greater than the energy band gap of the active layer 126 and / or the second conductive semiconductor layer 127.

[0063] The barrier layer 129 may be made of In x1 Al y1 Ga 1-x1-y1 The barrier layer 129 may be made of a semiconductor material having a composition formula of N(0≤x1≤1, 0≤y1≤1, 0≤x1+y1≤1), for example, it may be selected from AlGaN, InGaN, InAlGaN, etc., but is not limited thereto. The barrier layer 129 may be formed by alternately arranging a first layer 129b with a high aluminum composition and a second layer 129a with a low aluminum composition.

[0064] Reference Figure 2 The first conductive type semiconductor layer, the barrier layer 126 b , the well layer 126 a , the 2-2 conductive type semiconductor layer 127 b , and the 2-1 conductive type semiconductor layer 127 a may all include a GaN-based semiconductor of aluminum.

[0065] The first conductive type semiconductor layer 124 , the barrier layer 126 b , the well layer 126 a , the 2-2 conductive type semiconductor layer 127 b , and the 2-1 conductive type semiconductor layer 127 a may be AlGaN, but are not limited thereto.

[0066] The thickness of the 2-2 conductive type semiconductor layer 127b may be greater than 10nm and less than 200nm. If the thickness of the 2-2 conductive type semiconductor layer 127b is less than 10nm, it is difficult for the current in the 2-2 conductive type semiconductor layer 127b to be uniformly dispersed, and it is difficult for the current to be uniformly injected into the area above the semiconductor device. In addition, if the thickness of the 2-2 conductive type semiconductor layer 127b is greater than 200nm, the resistance increases, thereby reducing the injection efficiency of the current injected into the active layer 126.

[0067] The aluminum composition of the 2-2 conductive type semiconductor layer 127b may be greater than the aluminum composition of the well layer 126a. The aluminum composition of the well layer 126a may be about 30% to 50% in order to generate ultraviolet light. If the aluminum composition of the 2-2 conductive type semiconductor layer 127b is less than the aluminum composition of the well layer 126a, the 2-2 conductive type semiconductor layer 127b absorbs light, thereby reducing light extraction efficiency.

[0068] The aluminum composition of the 2-2 conductive type semiconductor layer 127b may be equal to or greater than 40% and equal to or less than 80%. If the aluminum composition of the 2-2 conductive type semiconductor layer 127b is equal to or greater than 40%, the light absorption problem may be improved. If the aluminum composition of the 2-2 conductive type semiconductor layer 127b is equal to or less than 80%, the problem of decreased current injection efficiency may be solved. Exemplarily, if the aluminum composition of the well layer 126a is 30%, the average aluminum composition of the 2-2 conductive type semiconductor layer 127b may be 40%.

[0069] The aluminum composition of the 2-1 conductive type semiconductor layer 127a may be less than that of the well layer 126a. If the aluminum composition of the 2-1 conductive type semiconductor layer 127a is greater than that of the well layer 126a, the resistance between the 2-1 conductive type semiconductor layer 127a and the p-ohmic electrode increases, resulting in failure to achieve sufficient ohmic contact and reducing current injection efficiency.

[0070] The aluminum composition of the 2-1 conductive type semiconductor layer 127a may be greater than 1% and less than 50%. If the aluminum composition is greater than 50%, sufficient ohmic contact with the p-ohmic electrode may not be achieved. If the aluminum composition is less than 1%, there is a problem of light absorption due to the composition being close to GaN.

[0071] The thickness of the 2-1st conductive type semiconductor layer 127a may be greater than 1 nm and less than 30 nm. As described above, the 2-1st conductive type semiconductor layer 127a has a low aluminum composition for ohmic contact, so it can absorb ultraviolet light. Therefore, it is advantageous from the perspective of light output to control the thickness of the 2-1st conductive type semiconductor layer 127a to be as low as possible.

[0072] However, if the thickness of the 2-1 conductive type semiconductor layer 127a is controlled to be equal to or less than 1 nm, there may be a region where the 2-1 conductive type semiconductor layer 127a is not arranged and the 2-2 conductive type semiconductor layer 127b is exposed to the outside of the semiconductor structure 120. Therefore, the injection efficiency of the current injected into the semiconductor device will be reduced, and the operating voltage of the semiconductor device will increase. In addition, if the thickness is greater than 30 nm, the amount of light absorbed becomes too large, so the light output efficiency will be reduced.

[0073] The 2-1st conductive type semiconductor layer 127a may include a surface layer 127a-2 and an adjustment layer 127a-1. The surface layer 127a-2 may be a region in contact with the p-ohmic electrode, and the adjustment layer 127a-1 may be a region for adjusting the aluminum composition.

[0074] The aluminum composition of the surface layer 127 a - 2 may be greater than 1% and less than 20%.

[0075] If the aluminum composition is equal to or greater than 1%, the problem of excessive light absorption rate in the surface layer 127a-2 can be solved. If the aluminum composition is equal to or less than 20%, the contact resistance with the second electrode (p-ohmic electrode) is too high, thereby improving the problem of reduced current injection efficiency.

[0076] However, the present invention is not limited thereto, and the aluminum composition of the surface layer 127a-2 may be adjusted in consideration of current injection characteristics and light absorption rate, or may be adjusted according to the light output required by the product.

[0077] For example, in a product in the field of semiconductor device application, if the current injection characteristic is more important than the light absorption rate, the aluminum composition ratio of the surface layer 127a-2 can be adjusted to 1% to 10%. Also, in a product in the field of semiconductor device application, if the light output characteristic is more important than the electrical characteristic, the aluminum composition ratio of the surface layer 127a-2 can be adjusted to 10% to 20%.

[0078] If the aluminum composition ratio of the surface layer 127a-2 is greater than 1% and less than 20%, the resistance between the surface layer 127a-2 and the second electrode is reduced, so the operating voltage is reduced. Therefore, the electrical characteristics are improved. The thickness of the surface layer 127a-2 can be greater than 1nm and less than 10nm. Therefore, the light absorption problem can be improved.

[0079] The thickness of the 2-1st conductive type semiconductor layer 127a may be less than the thickness of the 2-2nd conductive type semiconductor layer 127b. The thickness ratio of the 2-1st conductive type semiconductor layer 127a to the 2-2nd conductive type semiconductor layer 127b may be 1:1.5 to 1:20. If the thickness ratio is equal to or greater than 1:1.5 (e.g., 1:1.6), sufficient thickness of the 2-2nd conductive type semiconductor layer 127b is ensured, thereby improving current injection efficiency. Furthermore, if the thickness ratio is equal to or less than 1:20, the problem of reduced ohmic reliability due to the thin thickness of the 2-1st conductive type semiconductor layer 127a can be solved.

[0080] The aluminum composition of the 2-2 conductive type semiconductor layer 127b may decrease with a second slope L2 as it is further away from the active layer 126. Also, the aluminum composition of the 2-1 conductive type semiconductor layer 127a may decrease with a first slope L1 as it is further away from the active layer 126. Therefore, the aluminum composition of the surface layer 127a-2 may satisfy 1% to 20%.

[0081] However, the present invention is not limited thereto, and the aluminum composition of the 2-2 conductive type semiconductor layer 127 b and the 2-1 conductive type semiconductor layer 127 a does not decrease continuously, but may include a region where the aluminum composition does not decrease in a certain region.

[0082] The aluminum reduction range of the 2-1st conductivity type semiconductor layer 127a may be greater than that of the 2-2nd conductivity type semiconductor layer 127b. That is, the first slope L1 may be greater than the second slope L2. Here, the slope is determined by the thickness of the semiconductor layer and the aluminum reduction range.

[0083] The 2-2nd conductivity type semiconductor layer 127b is thicker than the 2-1st conductivity type semiconductor layer 127a, and in contrast, the change in aluminum composition thereof is relatively small, so the second slope L2 may be relatively slow.

[0084] However, the thickness of the 2-1st conductive type semiconductor layer 127a is thin and the variation range of the aluminum composition is large, and therefore, the first slope L1 may be relatively large.

[0085] Figure 3a is a conceptual diagram of a semiconductor structure according to another embodiment of the present invention. Figure 3b 2 is a graph showing the aluminum composition according to another embodiment of the present invention.

[0086] Reference Figure 3a and Figure 3b According to the embodiment, the semiconductor device includes a semiconductor structure 120B, which includes a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, an active layer 126 arranged between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127, and a third conductive semiconductor layer 124-1 arranged on the second conductive semiconductor layer 127.

[0087] The thickness of the second conductive semiconductor layer 127 may be greater than 20 nm and less than 200 nm. If the thickness of the second conductive semiconductor layer 127 is less than 20 nm, the resistance increases, resulting in reduced current injection efficiency. In addition, if the thickness of the second conductive semiconductor layer 127 is greater than 200 nm, the thickness of the second conductive semiconductor layer 127 is too large, so the crystallinity may deteriorate, and the probability of light emitted by the active layer 126 being absorbed increases.

[0088] The aluminum composition of the second conductive semiconductor layer 127 may be greater than 40% and less than 80%. If the aluminum composition of the second conductive semiconductor layer 127 is less than 40%, there is a problem of light absorption. If the aluminum composition of the second conductive semiconductor layer 127 is greater than 80%, there is a problem of poor crystallinity and insufficient current injection efficiency.

[0089] The aluminum composition of the third conductive semiconductor layer 124-1 may be greater than 1% and less than 60%. The third conductive semiconductor layer 124-1 may be doped with an n-type dopant and have the same polarity as the first conductive semiconductor layer 124. For example, the first conductive semiconductor layer 124 and the third conductive semiconductor layer 124-1 may be n-AlGaN. Among them, the second conductive semiconductor layer 127 may be p-AlGaN doped with a p-type dopant.

[0090] The electrical characteristics between the third conductive semiconductor layer 124-1 and the second electrode (ITO) are better than those between the second conductive semiconductor layer 127 and the second electrode (ITO), so its aluminum composition can be controlled to be higher than that of the well layer 126a. Therefore, the amount of light absorbed is reduced, thereby improving light output.

[0091] The thickness of the third conductive semiconductor layer 124-1 may be less than 10 nm. If the thickness of the third conductive semiconductor layer 124-1 is greater than 10 nm, there is a problem of weakened tunneling effect. Therefore, the injection efficiency of the second carrier injected into the active layer 126 through the second conductive semiconductor layer 127 is reduced. Therefore, the thickness of the third conductive semiconductor layer 124-1 may be less than that of the second conductive semiconductor layer 127.

[0092] Figure 4 is a conceptual diagram of a semiconductor device according to an embodiment of the present invention.

[0093] Reference Figure 4 The structure of the semiconductor structure 120 can be directly applied to Figure 1 and Figure 2 The groove 128 may be arranged from the bottom surface of the second conductive type semiconductor layer 127 through the active layer 126 to a portion of the first conductive type semiconductor layer 124 .

[0094] The first conductive layer 165 includes a connection electrode 167 disposed in the groove 128 and electrically connected to the first conductive type semiconductor layer 124. The first electrode 142 may be disposed between the connection electrode 167 and the first conductive type semiconductor layer 124. The first electrode 142 may be an ohmic electrode.

[0095] The distance from the top of the first groove 128 to the top of the semiconductor structure can be set to 1 μm to 4 μm. If the distance from the top of the semiconductor structure to the top of the first groove 128 is less than 1 μm, the reliability of the light emitting element will be reduced, and if the above distance is greater than 4 μm, the light extraction efficiency will be reduced due to crystal defects arranged in the semiconductor structure.

[0096] The second conductive layer 150 may be disposed under and electrically connected to the 2-1 conductive type semiconductor layer. The second conductive layer 150 may be disposed in a region between the plurality of connection electrodes 167. A region of the second conductive layer 150 may be exposed and electrically connected to the second electrode pad 166.

[0097] The second electrode 246 may be disposed between the second conductive layer 150 and the 2-1st conductive type semiconductor layer 127a and electrically connected. The aluminum composition of the surface layer of the 2-1st conductive type semiconductor layer 127a is relatively low, so ohmic connection can be easy. Also, the thickness of the 2-1st conductive type semiconductor layer 127a is greater than 1nm and less than 30nm, so the light absorption amount is small.

[0098] The first conductive layer 165 and the second conductive layer 150 may be formed of a transparent conductive oxide (TCO). The transparent conductive oxide may be selected from indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), aluminum gallium zinc oxide (AGZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium oxide (IGTO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZO nitride (IZON), ZnO, IrOx, RuOx, NiO, etc.

[0099] The first conductive layer 165 and the second conductive layer 150 may include an opaque metal, for example, Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, etc. Also, the first conductive layer 165 may be a single layer or multiple layers formed by mixing a transparent conductive oxide and an opaque metal, but is not limited thereto.

[0100] The insulating layer 130 may be made of a material selected from SiO2, Si x O y 、Si3N4、Si x N y 、SiO x The insulating layer 130 may be formed of at least one of the group consisting of Ny, Al 2 O 3 , TiO 2 , AlN, etc., but is not limited thereto. The insulating layer 130 may electrically insulate the connection electrode 167 from the active layer 126 and the second conductive type semiconductor layer 127 .

[0101] Figure 5 is a conceptual diagram of a semiconductor device according to another embodiment of the present invention.

[0102] Figure 5 The semiconductor structure 120 can be directly applied to Figure 1 Or the composition of the semiconductor structure 120 illustrated in FIG. 3 . Figure 5 Schematically showing the Figure 1 A semiconductor structure 120A having a structure of.

[0103] The first electrode 142 may be disposed on the groove 128 and electrically connected to the first conductive type semiconductor layer 124. The second electrode 246 may be formed at a lower portion of the second conductive type semiconductor layer 127.

[0104] The second electrode 246 may be in contact with and electrically connected to the 2-1st conductive type semiconductor layer.

[0105] The aluminum composition of the 2-1 conductive type semiconductor layer 127a in contact with the second electrode 246 is 1% to 20%, so that ohmic connection with the second electrode 246 is easy. In addition, the thickness of the 2-1 conductive type semiconductor layer 127a may be greater than 1nm and less than 30nm, so the light absorption amount is small.

[0106] The first electrode 142 and the second electrode 246 may be ohmic electrodes. The first electrode 142 and the second electrode 246 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZO nitride (IZON), aluminum gallium zinc oxide (AGZO), indium gallium zinc oxide (IGZO), indium gallium oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZO nitride (IZON), aluminum gallium zinc oxide (AGZO), indium gallium zinc oxide (IGZO), indium gallium zinc oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZO nitride (IZON), aluminum gallium zinc oxide (AGZO), indium gallium zinc oxide (IGZO), indium gallium zinc oxide (IGZO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), aluminum zinc oxide (GZO), indium gallium zinc oxide (AGZO), indium gallium zinc oxide (IGZO), aluminum zinc oxide (IGZO), aluminum zinc oxide (AG ... Oxide, IGZO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au or Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, Hf, but not limited to the above materials.

[0107] A second electrode pad 166 may be arranged at one side edge region of the semiconductor device. The second electrode pad 166 is arranged on the region where a portion of the first insulating layer 130 and the passivation layer 180 are removed, so that the center portion is sunken, so that there may be a concave portion and a convex portion on the upper portion. The upper concave portion may be bonded with a lead (not shown in the figure). Therefore, due to the widening of the bonding area, the second electrode pad 166 is more firmly bonded to the lead.

[0108] The second electrode pad 166 may play a role of reflecting light, and therefore, the closer the second electrode pad 166 is to the semiconductor structure 120 , the higher the light extraction efficiency is.

[0109] The convex portion of the second electrode pad 166 may be higher than the active layer 126. Therefore, the second electrode pad 166 reflects light emitted from the active layer 126 in a horizontal direction of the element upward, thereby being able to improve light extraction efficiency and control a directivity angle.

[0110] A portion of the first insulating layer 131 is opened below the second electrode pad 166 so that the second conductive layer 150 and the second electrode 246 can be electrically connected. A passivation layer 180 may be formed on the upper surface and side surfaces of the semiconductor structure 120. The passivation layer 180 may contact the first insulating layer 131 in a region adjacent to the second electrode 246 or below the second electrode 246.

[0111] For example, the width D22 of the portion where the second electrode pad 166 and the second conductive layer 150 are in contact due to the opening of the first insulating layer 131 may be 40 μm to 90 μm. If the width D22 is less than 40 μm, there is a problem of increased operating voltage. If the width D22 is greater than 90 μm, it is difficult to ensure a process margin for preventing the second conductive layer 150 from being exposed to the outside. If the second electrode 246 of the second conductive layer 150 is exposed to the external area, the reliability of the element will be reduced. Therefore, preferably, the width D22 may be 60% to 95% of the entire width of the second electrode pad 166.

[0112] The first insulating layer 131 may electrically insulate the first electrode 142 from the active layer 126 and the second conductive type semiconductor layer 127. Also, the first insulating layer 131 may electrically insulate the second electrode 246 from the second conductive layer 150 and the first conductive layer 165.

[0113] The first insulating layer 131 may be made of a material selected from SiO2, Si x O y 、Si3N4、Si x N y 、SiO x The first insulating layer 131 may be formed of at least one of the group consisting of Ny, Al2O3, TiO2, AlN, etc., but is not limited thereto. The first insulating layer 131 may be a single layer or a multilayer. Exemplarily, the first insulating layer 131 may be a distributed Bragg reflector (DBR) having a multilayer structure including Si oxide or Ti compound. However, the present invention is not limited thereto, and the first insulating layer 131 may include various reflective structures.

[0114] If the first insulating layer 131 has a reflective function, light emitted from the active layer 126 to the side is reflected upward, thereby improving light extraction efficiency. As described below, in an ultraviolet semiconductor device, the more grooves 128 there are, the more effective the light extraction efficiency is.

[0115] The second conductive layer 150 may be disposed at a lower portion of the second electrode 246. Therefore, the second electrode pad 166, the second conductive layer 150, and the second electrode 246 may form an electrical channel.

[0116] The second conductive layer 150 may completely surround the second electrode 246 and contact the side and top of the first insulating layer 131. The second conductive layer 150 is formed of a material having a high adhesive force with the first insulating layer 131, and may be formed of a material selected from the group consisting of Cr, Al, Ti, Ni, Au, etc., and alloys thereof, and may be a single layer or multiple layers.

[0117] If the second conductive layer 150 is in contact with the side surface and the top surface of the first insulating layer 131, the thermoelectric reliability of the second electrode 246 can be improved. In addition, the second conductive layer 150 can have a reflective function of reflecting light emitted between the first insulating layer 131 and the second electrode 246 upward.

[0118] The second conductive layer 150 may be arranged at a second isolation distance, which is a region where the second conductive type semiconductor layer is exposed between the first insulating layer 131 and the second electrode 246. The second conductive layer 150 may be in contact with the side and top surfaces of the second electrode 246 and the side and top surfaces of the first insulating layer 131 at the second isolation distance.

[0119] Furthermore, a region where the second conductive layer 150 and the second conductive semiconductor layer 127 are connected to form a Schottky junction may be arranged in the second isolation distance, and current spreading may be easily achieved by forming the Schottky junction.

[0120] The second insulating layer 132 electrically insulates the second electrode 246, the second conductive layer 150, and the first conductive layer 165. The first conductive layer 165 may pass through the second insulating layer 132 to be electrically connected to the first electrode 142.

[0121] The first conductive layer 165 and the adhesive layer 160 may be arranged along the bottom of the semiconductor structure 120 and the shape of the groove 128. The first conductive layer 165 may be formed of a material with good reflectivity. Exemplarily, the first conductive layer 165 may include aluminum. If the first conductive layer 165 includes aluminum, the first conductive layer 165 is used to reflect light emitted from the active layer 126 upward to improve light extraction efficiency.

[0122] The adhesive layer 160 may include a conductive material. For example, the adhesive layer 160 may include a material selected from the group consisting of gold, tin, indium, aluminum, silicon, silver, nickel, and copper, or an alloy thereof.

[0123] The substrate 170 may be formed of a conductive material. For example, the substrate 170 may include a metal or a semiconductor material. The substrate 170 may be a metal having excellent electrical conductivity and / or thermal conductivity. In this case, the heat generated when the semiconductor device is in operation may be quickly discharged to the outside.

[0124] The substrate 170 may include a material selected from the group consisting of silicon, molybdenum, silicon, tungsten, copper, and aluminum, or an alloy thereof.

[0125] Concavoconvex may be formed on the semiconductor structure 120. The concavoconvex may improve the extraction efficiency of light emitted from the semiconductor structure 120. The average height of the concavoconvex may be different according to the wavelength of ultraviolet rays. In the case of UV-C, the average height of the concavoconvex is about 300nm to 800nm. When the average height of the concavoconvex is about 500nm to 600nm, the light extraction efficiency may be improved.

[0126] Figure 6a and Figure 6b is a plan view of a semiconductor device according to an embodiment of the present invention.

[0127] If the Al composition of the semiconductor structure 120 increases, the current diffusion characteristics in the semiconductor structure 120 may be reduced. In addition, the amount of light emitted to the side by the active layer 126 may be increased compared to a GaN-based blue light emitting element (TM mode). The TM mode may occur in ultraviolet semiconductor devices.

[0128] According to the embodiment, a GaN semiconductor emitting light of a wavelength band of an ultraviolet region may form more grooves 128 to arrange the first electrode 142 for current diffusion than a GaN semiconductor emitting blue light.

[0129] Reference Figure 6a , if the composition of Al increases, the current dispersion characteristics will deteriorate. Therefore, the current is dispersed only in the vicinity of each first electrode 142, and the current density will drop sharply in the distant location. Therefore, the effective light-emitting area C2 will become narrower. The effective light-emitting area C2 can be defined as an area based on the current density at the vicinity of the first electrode 142 where the current density is the highest to the boundary location where the current density is equal to or less than 40%. For example, the effective light-emitting area C2 can be adjusted within a range of 5μm to 40μm from the center of the groove 128 according to the level of the injected current and the composition of Al.

[0130] In particular, the low current density region C3 between adjacent first electrodes 142 has low current density and thus has little effect on light emission. Therefore, the embodiment can improve light output by further arranging the first electrode 142 in the low current density region C3 where the current density is low.

[0131] Generally, in the case of a GaN semiconductor layer, the current spreading characteristic is relatively good, and therefore, it is preferable to minimize the area of ​​the groove 128 and the first electrode 142. This is because the larger the area of ​​the groove 128 and the first electrode 142, the smaller the area of ​​the active layer 126. However, in the case of the embodiment, since the composition of Al is high, the current spreading characteristic is worse than that of a semiconductor device emitting blue light, and therefore, it is preferable to increase the number of the first electrode 142 to reduce the low current density region C3 even at the expense of the area of ​​the active layer 126.

[0132] Reference Figure 6b , if the number of grooves 128 is 48, the grooves 128 cannot be arranged in a straight line in the horizontal and vertical directions, but can only be arranged in a zigzag shape. In this case, the area of ​​the low current density region C3 becomes narrower, so that most of the active layer can participate in light emission. If the number of grooves 128 is 70 to 110, the current is more effectively dispersed, the operating voltage can be reduced, and the light output can be improved. In a semiconductor device that emits UV-C light, if the number of grooves 128 is less than 70, the electrical and optical properties will be reduced. If the number of grooves 128 is greater than 110, although the electrical characteristics can be improved, the volume of the light-emitting layer is reduced, so that the optical characteristics will be reduced.

[0133] The first area where the first electrodes 142 are in contact with the first conductive semiconductor layer 122 may be greater than 7.4% and less than 20%, or greater than 10% and less than 20%, of the maximum horizontal cross-sectional area of ​​the semiconductor structure 120. The first area may be the sum of the areas where the first electrodes 142 are in contact with the first conductive semiconductor layer 122.

[0134] If the first area of ​​the plurality of first electrodes 142 is 7.4% or more, sufficient current diffusion characteristics can be achieved and light output can be improved. If the first area of ​​the plurality of first electrodes 142 is 20% or less, the area of ​​the active layer and the second electrode can be ensured to improve light output and operating voltage characteristics.

[0135] Furthermore, the total area of ​​the plurality of grooves 128 may be greater than 13% and less than 30% of the maximum horizontal cross-sectional area of ​​the semiconductor structure 120. If the total area of ​​the grooves 128 cannot meet the above conditions, it is difficult to control the total area of ​​the first electrode 142 to be greater than 7.4% and less than 20%. Furthermore, it may also lead to problems such as increased operating voltage and reduced light output.

[0136] The second area where the second electrode 246 contacts the second conductive semiconductor layer 126 may be greater than 35% and less than 70% of the maximum horizontal cross-sectional area of ​​the semiconductor structure 120. The second area may be the total area where the second electrode 246 contacts the second conductive semiconductor layer 126.

[0137] If the second area is greater than 35%, the area of ​​the second electrode can be ensured to improve the second carrier injection efficiency and operating voltage characteristics. Also, if the second area is less than 70%, the first area can be effectively increased to improve the first carrier injection efficiency.

[0138] The first area and the second area are inversely proportional. That is, if the number of grooves is increased in order to increase the number of first electrodes, the area of ​​the second electrode will decrease. In order to increase the light output, the first carrier and the second carrier should be balanced. Therefore, it is important to determine the appropriate ratio of the first area and the second area.

[0139] Therefore, in order to control the first carrier and the second carrier injected into the active layer 126 by an appropriate ratio of the first area to the second area, the ratio of the first area of ​​the multiple first electrodes in contact with the first conductive semiconductor layer and the second area of ​​the second electrodes in contact with the second conductive semiconductor layer (first area: second area) can be 1:3 to 1:10.

[0140] Figure 7 A conceptual diagram of a semiconductor structure grown on a substrate. Figure 8 2 is a diagram for explaining a process of separating a substrate. Fig. 9 1 is a diagram for illustrating a process of etching a semiconductor structure. Fig.10 2 is a diagram showing a manufactured semiconductor device.

[0141] Reference Figure 7 , a buffer layer 122 , a light absorbing layer 123 , a first conductive type semiconductor layer 124 , an active layer 126 , a second conductive type semiconductor layer 127 , a second electrode 246 and a second conductive layer 150 may be sequentially formed on a growth substrate 121 .

[0142] The light absorbing layer 123 includes a first light absorbing layer 123a having a low aluminum composition and a second light absorbing layer 123b having a high aluminum composition. A plurality of first light absorbing layers 123a and second light absorbing layers 123b may be alternately arranged.

[0143] The aluminum composition of the first light absorbing layer 123a may be lower than the aluminum composition of the first conductive type semiconductor layer 124. The first light absorbing layer 123a may be used to absorb laser light for separation during the LLO process. Thus, the growth substrate may be removed.

[0144] In order to absorb laser light having a predetermined wavelength (e.g., 246 nm), the thickness and aluminum composition of the first light absorbing layer 123a may be appropriately adjusted. The aluminum composition of the first light absorbing layer 123a may be 20% to 50%, and the thickness may be 1 nm to 10 nm. Exemplarily, the first light absorbing layer 123a may be AlGaN, but is not limited thereto.

[0145] The aluminum composition of the second light absorbing layer 123b may be higher than that of the first conductive type semiconductor layer 124. The second light absorbing layer 123b improves the crystallinity of the first conductive type semiconductor layer 124 grown on the light absorbing layer 123 by improving the aluminum composition reduced by the first light absorbing layer 123a.

[0146] For example, the aluminum composition of the second light absorbing layer 123b may be 60% to 100%, and the thickness may be 0.1 nm to 2.0 nm. The second light absorbing layer 123b may be AlGaN or AlN.

[0147] In order to absorb laser light of a wavelength of 246 nm, the thickness of the first light absorbing layer 123 a may be greater than that of the second light absorbing layer 123 b. The thickness of the first light absorbing layer 123 a may be 1 nm to 10 nm, and the thickness of the second light absorbing layer 123 b may be 0.5 nm to 2.0 nm.

[0148] The thickness ratio of the first light absorbing layer 123a to the second light absorbing layer 123b may be 2: 1 to 6: 1. If the thickness ratio is less than 2: 1, the first light absorbing layer 123a becomes thinner and thus it is difficult to fully absorb laser light, and if the thickness ratio is greater than 6: 1, the second light absorbing layer 123b becomes too thin and thus the entire aluminum composition of the light absorbing layer is reduced.

[0149] The entire thickness of the light absorbing layer 123 may be greater than 100 nm and less than 400 nm. If the thickness is less than 100 nm, the thickness of the first light absorbing layer 123a becomes thinner, so it is difficult to fully absorb the 246 nm laser. If the thickness is greater than 400 nm, the aluminum composition is reduced as a whole, resulting in a decrease in crystallinity.

[0150] According to the embodiment, the crystallinity can be improved by forming the light absorbing layer 123 having the super lattice structure. With the above configuration, the light absorbing layer 123 can be used as a buffer layer to alleviate the lattice mismatch between the growth substrate 121 and the semiconductor structure 120.

[0151] Reference Figure 8 The step of removing the growth substrate 121 can be achieved by irradiating the growth substrate 121 with laser light L1 to separate the growth substrate 121. The laser light L1 can have a wavelength band capable of absorbing the first light absorption layer 123a. As an example, the laser light can be a KrF laser with a wavelength band of 248nm.

[0152] The growth substrate 121 and the second light absorbing layer 123 b have a large energy band gap and thus do not absorb the laser light L1 . However, the first light absorbing layer 123 a having a low aluminum composition can absorb the laser light L1 to be decomposed. Therefore, it can be separated together with the growth substrate 121 .

[0153] Thereafter, the light absorbing layer 123 - 2 remaining on the first conductive type semiconductor layer 124 a may be removed by leveling.

[0154] Reference Fig. 9After forming the second conductive layer 150 on the second conductive semiconductor layer 127, a plurality of grooves 128 penetrating a portion of the first conductive semiconductor layer 124 of the semiconductor structure 120 may be formed. Thereafter, an insulating layer 130 may be formed on the side of the grooves 128 and on the second conductive semiconductor layer 127. Then, a first electrode 142 may be formed on the first conductive semiconductor layer 124 b exposed by the grooves 128.

[0155] Reference Fig.10 , the first conductive layer 165 may be formed at a lower portion of the insulating layer 130. The first conductive layer 165 may be electrically insulated from the second conductive layer 150 by the insulating layer 130.

[0156] Thereafter, a conductive substrate 170 may be formed at a lower portion of the first conductive layer 165 , and a second electrode pad 166 may be formed on the second conductive layer 150 exposed by mesa etching.

[0157] Fig.11 is a conceptual diagram of a semiconductor structure according to a third embodiment of the present invention, Fig.12 FIG. 4 is a graph showing the aluminum composition of a semiconductor structure according to a third embodiment of the present invention.

[0158] Reference Fig.11 , the semiconductor device according to the embodiment includes a semiconductor structure 120 including a first conductive type semiconductor layer 124 , a second conductive type semiconductor layer 127 , and an active layer 126 disposed between the first conductive type semiconductor layer 124 and the second conductive type semiconductor layer 127 .

[0159] The first conductive type semiconductor layer 124 may include a 1-1 conductive type semiconductor layer 124 a , a 1-2 conductive type semiconductor layer 124 c , and an intermediate layer 124 b disposed between the 1-1 conductive type semiconductor layer 124 a and the 1-2 conductive type semiconductor layer 124 c .

[0160] The 1-2 conductive type semiconductor layer 124c may be closer to the active layer 126 than the 1-1 conductive type semiconductor layer 124a. The aluminum composition of the 1-2 conductive type semiconductor layer 124c may be lower than that of the 1-1 conductive type semiconductor layer 124a. The aluminum composition of the 1-2 conductive type semiconductor layer 124c may be 40% to 70%, and the aluminum composition of the 1-1 conductive type semiconductor layer 124a may be 50% to 80%.

[0161] The thickness of the 1-2 conductive type semiconductor layer 124c may be less than the thickness of the 1-1 conductive type semiconductor layer 124a. The thickness of the 1-1 conductive type semiconductor layer 124a may be equal to or greater than 130% of the thickness of the 1-2 conductive type semiconductor layer 124c and equal to or less than 500% of the thickness of the 1-2 conductive type semiconductor layer 124c. If the thickness of the 1-1 conductive type semiconductor layer 124a is less than 130% of the thickness of the 1-2 conductive type semiconductor layer 124c, the crystallinity of the intermediate layer 124b, the 1-2 conductive type semiconductor layer 124c, etc. disposed on the 1-1 conductive type semiconductor layer 124a may be reduced. If the thickness of the 1-1 conductive type semiconductor layer 124a is greater than 500% of the thickness of the 1-2 conductive type semiconductor layer 124c, the thickness of the entire semiconductor structure becomes too thick. Therefore, too much stress is applied to the inside of the semiconductor structure, resulting in cracks in the semiconductor structure, or the wavelength of light emission may change. According to the above structure, the intermediate layer 124b is formed after the 1-1 conductive type semiconductor layer 124a with a high aluminum composition is fully grown. Therefore, the crystallinity of the entire semiconductor structure 120 is improved, and the wavelength of light emitted by the user can be adjusted.

[0162] The aluminum composition of the intermediate layer 124b may be lower than the aluminum composition of the first conductive semiconductor layer 124. The intermediate layer 124b may be used to absorb the laser irradiated to the semiconductor structure 120 during the LLO process to prevent damage to the active layer 126. Therefore, the semiconductor device according to the embodiment reduces damage to the active layer, thereby being able to improve light output and electrical characteristics.

[0163] The thickness and aluminum composition of the intermediate layer 124b can be appropriately adjusted during the LLO process in order to absorb the laser having the wavelength of the laser irradiated to the semiconductor structure 120. Exemplarily, the aluminum composition of the intermediate layer 124b can be 30% to 60%, and the thickness can be 1nm to 10nm. Exemplarily, the intermediate layer 124b can be AlGaN, but is not limited thereto.

[0164] The intermediate layer 124b may be disposed between the first conductive type semiconductor layer 124 and the active layer 126. Also, the intermediate layer 124b may include a first intermediate layer having an aluminum composition lower than that of the first conductive type semiconductor layer 124 and a second intermediate layer having an aluminum composition higher than that of the first conductive type semiconductor layer 124. A plurality of first intermediate layers and second intermediate layers may be alternately disposed.

[0165] The active layer 126 may be disposed between the first conductive type semiconductor layer 124 and the second conductive type semiconductor layer 127. The active layer 126 is a layer where electrons (or holes) injected through the first conductive type semiconductor layer 124 and holes (or electrons) injected through the second conductive type semiconductor layer 127 meet.

[0166] The second conductive semiconductor layer 127 is formed on the active layer 126 and can be made of compound semiconductors of group III-V, group II-VI, etc. The second conductive semiconductor layer 127 can be doped with a second dopant. x5 Al y2 Ga 1-x5-y2 N(0≤x5≤1, 0≤y2≤1, 0≤x5+y2≤1), or may be formed of a material selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP. If the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, Ba, etc., the second conductive semiconductor layer 127 doped with the second dopant may be a p-type semiconductor layer.

[0167] The second conductive type semiconductor layer 127 may include a 2-1 conductive type semiconductor layer 127a, a 2-2 conductive type semiconductor layer 127b, and a 2-3 conductive type semiconductor layer 127c. The aluminum composition of the 2-1 conductive type semiconductor layer 127a may be lower than that of the 2-2 conductive type semiconductor layer 127b.

[0168] The blocking layer 129 may be disposed between the active layer 126 and the second conductive type semiconductor layer 127. The blocking layer 129 may block the flow of first carriers (eg, electrons) supplied from the first conductive type semiconductor layer 124 from leaking to the second conductive type semiconductor layer 127.

[0169] Reference Fig.12 The first conductive type semiconductor layer 124, the active layer 126, the second conductive type semiconductor layer 127 and the barrier layer 129 may include aluminum. Therefore, the first conductive type semiconductor layer 124, the active layer 126, the second conductive type semiconductor layer 127 and the barrier layer 129 may have an AlGaN composition.

[0170] The aluminum composition of the barrier layer 129 may be 50% to 100%. If the aluminum composition of the barrier layer 129 is less than 50%, the height of the energy barrier for blocking electrons may be insufficient, and there may be a problem that light emitted from the active layer 126 is absorbed in the barrier layer 129.

[0171] The barrier layer 129 may include a 1-1 interval 129a and a 1-2 interval 129c. The barrier layer 129 may include a second dopant. The second dopant may include a p-type dopant such as Mg, Zn, Ca, Sr, Ba, etc. In the case of including a second dopant, the barrier layer 129 may include a dopant such as a second conductive semiconductor layer. However, the present invention is not limited thereto, and the barrier layer 129 may have the same polarity as the second conductive semiconductor layer 127, and may include a second dopant different from the second conductive semiconductor layer. With the help of the 1-1 interval 129a and the 1-2 interval 129c, the injection efficiency of the second carrier (for example, holes) is increased, and the resistance is reduced, so the operating voltage (Vf) can be improved. However, the present invention is not limited thereto, and the barrier layer 129 may not include a dopant. The aluminum composition of the 1-1 interval 129a may be higher as it is closer to the second conductive semiconductor layer 127. The aluminum composition of the region with the highest aluminum composition in the 1-1 interval 129a may be 80% to 100%. That is, the 1-1 section 129 a may be AlGaN, or may be AlN. Alternatively, the 1-1 section 129 a may be a superlattice layer in which AlGaN and AlN are alternately arranged.

[0172] The thickness of the 1-1 interval 129a may be about 0.1 nm to 4 nm. When the thickness of the 1-1 interval 129a is less than 0.1 nm, or / and when the aluminum composition of the region with the highest aluminum composition in the 1-1 interval 129a is less than 80%, there may be a problem that the movement of the first carrier (e.g., electron) cannot be effectively blocked. In addition, if the thickness of the 1-1 interval 129a is greater than 4 nm, the efficiency of injecting the second carrier (e.g., hole) into the active layer will be reduced.

[0173] The 1-2 interval 129c can play a role in effectively blocking the movement of the first carrier (e.g., electron) together with the 1-1 interval 129a. In order to improve the injection efficiency of the second carrier (e.g., hole), the 1-2 interval 129c can include a second dopant. The second dopant can include p-type dopants such as Mg, Zn, Ca, Sr, Ba, etc. The thickness of the 1-2 interval 129c can be 15nm to 30nm. If the thickness is less than 15nm, there may be a problem that the movement of the first carrier (e.g., electron) cannot be effectively blocked. In addition, if the thickness is greater than 30nm, the efficiency of injecting the second carrier (e.g., hole) into the active layer will be reduced.

[0174] An undoped interval 129b not doped with Mg may be arranged between the 1-1 interval 129a and the 1-2 interval 129c. The undoped interval 129b may be used to prevent the dopant included in the second conductive semiconductor layer 127 from diffusing from the second conductive semiconductor layer 127 to the active layer 126. The thickness of the undoped interval 129b may be 10nm to 15nm. If the thickness is less than 10nm, it will be difficult to prevent the dopant from diffusing into the active layer 126, and if the thickness is greater than 15nm, the injection efficiency of the second carrier (e.g., hole) will decrease.

[0175] The second conductive type semiconductor layer 127 may include a 2-1 conductive type semiconductor 127 a , a 2-2 conductive type semiconductor 127 b , and a 2-3 conductive type semiconductor layer 127 c .

[0176] The thickness of the 2-2 conductive type semiconductor layer 127b may be greater than 10nm and less than 50nm. Exemplarily, the thickness of the 2-2 conductive type semiconductor layer 127b may be 25nm. If the thickness of the 2-2 conductive type semiconductor layer 127b is less than 10nm, the resistance in the horizontal direction increases and the current injection efficiency decreases. Furthermore, if the thickness of the 2-2 conductive type semiconductor layer 127b is greater than 50nm, the resistance in the vertical direction increases and the current injection efficiency decreases.

[0177] The aluminum composition of the 2-2 conductive type semiconductor layer 127b may be higher than the aluminum composition of the well layer 126a. In order to generate ultraviolet light, the aluminum composition of the well layer 126a may be about 30% to 70%. If the aluminum composition of the 2-2 conductive type semiconductor layer 127b is lower than the aluminum composition of the well layer 126a, the 2-2 conductive type semiconductor layer 127b absorbs light, so the light extraction efficiency is reduced, but the present invention is not limited thereto. Exemplarily, the aluminum composition of a portion of the 2-2 conductive type semiconductor layer 127b may be lower than the aluminum composition of the well layer 126a.

[0178] The aluminum composition of the 2-2 conductive type semiconductor layer 127b may be greater than 40% and less than 80%. If the aluminum composition of the 2-2 conductive type semiconductor layer 127b is less than 40%, there is a problem of light absorption. If the aluminum composition of the 2-2 conductive type semiconductor layer 127b is greater than 80%, there is a problem of reduced current injection efficiency. Exemplarily, if the aluminum composition of the well layer 126a is 30%, the aluminum composition of the 2-2 conductive type semiconductor layer 127b may be 40%.

[0179] The aluminum composition of the 2-1 conductive type semiconductor layer 127a may be lower than that of the well layer 126a. If the aluminum composition of the 2-1 conductive type semiconductor layer 127a is higher than that of the well layer 126a, the resistance between the second electrode increases, and sufficient ohmic contact cannot be achieved, and the current injection efficiency decreases.

[0180] The aluminum composition of the 2-1 conductive type semiconductor layer 127a may be greater than 1% and less than 50%. If the aluminum composition of the 2-1 conductive type semiconductor layer 127a is greater than 50%, sufficient ohmic contact with the second electrode cannot be achieved, and if the aluminum composition of the 2-1 conductive type semiconductor layer 127a is less than 1%, it seems to be close to the GaN composition, and therefore, there is a problem of difficulty in absorbing light.

[0181] The thickness of the 2-1st conductive type semiconductor layer 127a may be 1 nm to 30 nm or 1 nm to 10 nm. As described above, the 2-1st conductive type semiconductor layer 127a has a low aluminum composition for ohmic, and thus can absorb ultraviolet light. Therefore, it is advantageous from the perspective of light output to control the thickness of the 2-1st conductive type semiconductor layer 127a to be as small as possible.

[0182] However, if the thickness of the 2-1 conductive type semiconductor layer 127a is controlled to be equal to or less than 1 nm, the aluminum composition changes sharply, so the crystallinity is reduced. In addition, since the thickness of the 2-1 conductive type semiconductor layer 127a is too small, the resistance of the 2-1 conductive type semiconductor layer 127a in the horizontal direction increases, and the electrical characteristics of the semiconductor device are reduced. In addition, if the thickness of the 2-1 conductive type semiconductor layer 127a is greater than 30 nm, the light absorbed by the 2-1 conductive type semiconductor layer 127a becomes too large, so the light output efficiency is reduced.

[0183] The thickness of the 2-1 conductive type semiconductor layer 127a may be smaller than the thickness of the 2-2 conductive type semiconductor layer 127b. The thickness ratio of the 2-2 conductive type semiconductor layer 127b to the 2-1 conductive type semiconductor layer 127a may be 1.5:1 to 20:1. If the thickness ratio is less than 1.5:1, the thickness of the 2-2 conductive type semiconductor layer 127b becomes too small, so the current injection efficiency is reduced. And, if the thickness ratio is greater than 20:1, the thickness of the 2-1 conductive type semiconductor layer 127a becomes too small, so that the crystallinity is reduced and the electrical characteristics of the semiconductor device are reduced.

[0184] The aluminum composition of the 2-2 conductive type semiconductor layer 127 b may decrease as it is further away from the active layer 126 . Also, the aluminum composition of the 2-1 conductive type semiconductor layer 127 a may decrease as it is further away from the active layer 126 .

[0185] The aluminum reduction range of the 2-1 conductive type semiconductor layer 127a may be greater than the aluminum reduction range of the 2-2 conductive type semiconductor layer 127b. That is, the change rate of the Al composition ratio of the 2-1 conductive type semiconductor layer 127a in the thickness direction may be greater than the change rate of the Al composition ratio of the 2-2 conductive type semiconductor layer 127b in the thickness direction.

[0186] The thickness of the 2-2 conductive type semiconductor layer 127b is greater than that of the 2-1 conductive type semiconductor layer 127a. On the contrary, its aluminum composition should be higher than that of the well layer 126a, so the reduction range will be relatively slow. However, the thickness of the 2-1 conductive type semiconductor layer 127a is small, and the variation range of the aluminum composition is large, so the reduction range of the aluminum composition is relatively large. The thickness of the 2-1 conductive type semiconductor layer 127a is small, and the variation range of the aluminum composition is large, so it can grow relatively slowly and change the aluminum composition.

[0187] The 2-3 conductive type semiconductor layer 127c may have a uniform aluminum composition. The thickness of the 2-3 conductive type semiconductor layer 127c may be 20nm to 60nm. The aluminum composition of the 2-3 conductive type semiconductor layer 127c may be 40% to 70%. When the aluminum composition of the 2-3 conductive type semiconductor layer 127c is equal to or greater than 40%, the crystallinity of the 2-1 conductive type semiconductor layer 127a and the 2-2 conductive type semiconductor layer 127b will not decrease. When the aluminum composition of the 2-3 conductive type semiconductor layer 127c is less than 70%, the aluminum composition of the 2-1 conductive type semiconductor layer 127a and the 2-2 conductive type semiconductor layer 127b changes sharply, which can prevent the problem of reduced crystallinity, thereby improving the electrical characteristics of the semiconductor device.

[0188] As described above, the thickness of the 2-1st conductive type semiconductor layer 127a may be 1nm to 10nm, the thickness of the 2-2nd conductive type semiconductor layer 127b may be 10nm to 50nm, and the thickness of the 2-3rd conductive type semiconductor layer 127c may be 20nm to 60nm. Therefore, the ratio of the thickness of the 2-1st conductive type semiconductor layer 127a to the entire thickness of the second conductive type semiconductor layer 127 may be 1:3 to 1:120. If the ratio is greater than 1:3, the 2-1st conductive type semiconductor layer 127a may ensure the electrical characteristics (e.g., operating voltage) of the semiconductor device, and if the ratio is less than 1:120, the optical characteristics (e.g., light output) of the semiconductor device may be ensured. However, the present invention is not limited thereto, and the ratio of the thickness of the 2-1st conductive type semiconductor layer 127a to the entire thickness of the second conductive type semiconductor layer 127 may be 1:3 to 1:50 or 1:3 to 1:70.

[0189] Fig.13 SIM (Secondary ion mass spectrometry) chart showing the change in aluminum intensity of the semiconductor structure according to the third embodiment of the present invention. Fig.14 for Fig.13 A partial enlarged view of .

[0190] Reference Fig.13 and Fig.14As the first conductive semiconductor layer 124 approaches the second conductive semiconductor layer 127 , the aluminum ion intensity of the semiconductor structure changes.

[0191] The secondary ion mass spectrometry (SIMS) data may be data analyzed by time-of-flight secondary ion mass spectrometry (TOF-SIMS).

[0192] Secondary ion mass spectrometry (SIMS) data can be analyzed by counting the number of secondary ions emitted by irradiating the target surface with primary ions. The primary ions can be selected from O2 + , Cs + 、Bi + etc., the acceleration voltage can be adjusted in the range of 20 to 30 keV, the irradiation current can be adjusted in the range of 0.1 pA to 5.0 pA, and the irradiation area can be 20 nm × 20 nm.

[0193] As for secondary ion mass spectrometry (SIMS) data, the secondary ion mass spectrum can be collected while gradually etching from the surface of the second conductive semiconductor layer toward the first conductive semiconductor layer. Here, the secondary ions can be aluminum ions. The spectrum of aluminum ion intensity is represented by a linear scale, but is not limited thereto, and can also be represented by a logarithmic scale.

[0194] The semiconductor structure may have a first location P1 with the lowest aluminum ion intensity in the first conductive semiconductor layer 124, a second location P2 with the highest aluminum ion intensity in the barrier layer, and a third location P3 with the lowest aluminum ion intensity in the second conductive semiconductor layer 127. However, the present invention is not limited thereto, and the location with the highest and lowest aluminum ion intensity may be at other locations in the semiconductor structure instead of the above-mentioned locations.

[0195] The first location P1 may be located in the intermediate layer 124b disposed in the first conductive type semiconductor layer, and may be located in a region in contact with the first electrode 142. The second location P2 may be located in the 1-1 section 129a of the barrier layer 129. Furthermore, the third location P3 may be located in a contact layer (2-1 conductive type semiconductor layer) in which the second conductive type semiconductor layer is in direct contact with the second electrode (P-ohmic electrode).

[0196] When measuring the first location P1, the second location P2, and the third location P3 by SIMS, noise may be included in the semiconductor layer having a certain thickness or more. For example, the first location P1 may be defined as a layer having the same intensity as the layer with the lowest aluminum ion intensity in the first conductive semiconductor layer. The difference between the high point and the low point of the noise at the first location P1 may be within 2%.

[0197] A ratio D1:D2 of a first aluminum strength difference D1 between the first location P1 and the second location P2 and a second aluminum strength difference D2 between the first location P1 and the third location P3 may be 1:0.2 to 1:2.

[0198] If the strength difference is 1:0.2 or more, the second aluminum strength difference D2 can be sufficiently ensured, and thus the contact resistance between the second conductive semiconductor layer and the second electrode can be improved.

[0199] If the intensity difference is 1:2 or less, the second aluminum intensity difference D2 is prevented from being relatively increased, so that the aluminum intensity change rate with respect to the thickness of the 2-1 conductive type semiconductor layer 127a can be adjusted so as not to become too large. Therefore, the crystallinity of the semiconductor structure can be improved, and the light transmittance of the 2-1 conductive type semiconductor layer 127a with respect to the light emitted from the active layer 126 can be improved, so that the optical characteristics of the semiconductor device can be improved.

[0200] In contrast, when a GaN layer (surface layer) is inserted for ohmic contact between the second conductive semiconductor layer and the electrode, the second aluminum strength difference D2 increases sharply because the GaN layer in contact with the electrode does not include aluminum. Therefore, the ratio D1:D2 of the first aluminum strength difference D1 and the second aluminum strength difference D2 cannot exceed the range of 1:0.2 to 1:2.

[0201] The ratio W1:W2 of the first thickness W1 and the second thickness W2 of the semiconductor structure may be 1:0.2 to 1:1. The first thickness W1 may be the thickness of the semiconductor structure between the fourth location P1 and the second location P2 in the second conductive semiconductor layer 127, and the second thickness W2 may be the thickness of the semiconductor structure between the fourth location P1 and the third location P3 in the second conductive semiconductor layer 127.

[0202] If the ratio W1:W2 of the first thickness W1 and the second thickness W2 is equal to or greater than 1:0.2, the crystallinity can be improved by ensuring the second thickness W2.

[0203] Also, if the thickness ratio is equal to or less than 1:1, the second thickness W2 may be relatively reduced. Therefore, light extraction efficiency may be improved by solving the problem that light emitted from the active layer 126 is absorbed in the second thickness W2.

[0204] Reference Fig.15 The semiconductor structure may be formed by sequentially stacking a first conductive semiconductor layer 124, an active layer 126, a barrier layer 129, and a second conductive semiconductor layer 127. The second electrode may directly contact a surface 127a of the second conductive semiconductor layer 127, thereby forming an ohmic contact.

[0205] Fig.16 for Figure 1 Conceptual diagram of the second conductive semiconductor layer, Fig.17 AFM data for measuring the surface of the second conductive type semiconductor layer according to the third embodiment of the present invention, Fig.18 This is the AFM data for measuring the surface of GaN thin film. Fig.19 The AFM data are obtained by measuring the surface of the second conductive type semiconductor layer that is growing at a high speed.

[0206] Reference Fig.16 According to the embodiment, the second conductive type semiconductor layer 127 may include a 2-1 conductive type semiconductor layer 127a, a 2-2 conductive type semiconductor layer 127b, and a 2-3 conductive type semiconductor layer 127c. The 2-1 conductive type semiconductor layer 127a may be a contact layer in contact with the second electrode. The characteristics of each layer may be directly applied to the above content.

[0207] The surface of the 2-1 conductive type semiconductor layer 127a may include a plurality of clusters C1, and the clusters C1 may be protrusions protruding from the surface. For example, the clusters C1 may be protrusions protruding about 10 nm or more than 20 nm based on the average surface height. The clusters C1 may be formed due to lattice mismatch between aluminum (Al) and gallium (Ga).

[0208] The 2-1 conductive type semiconductor layer 127a according to the embodiment includes aluminum, and the aluminum variation rate according to the thickness is large, and the thickness is thinner than other layers, so a cluster C1 can be formed on the surface without forming a single layer on the surface. The cluster C1 may include Al, Ga, N, Mg, etc. However, the present invention is not limited thereto.

[0209] Reference Fig.17 , a relatively bright dot cluster C1 can be determined on the surface of the second conductive type semiconductor layer 127. According to the embodiment, the aluminum composition of the 2-1 conductive type semiconductor layer 127a is 1% to 10%, and thus, it can have the form of the cluster C1, so that the bonding area can be increased. Therefore, the electrical characteristics can be improved.

[0210] On average every 100 μm 2 100 to 800 clusters C1 can be observed on the surface of the second conductive semiconductor layer 127. The average value may be the average value measured at about 10 different locations. Fig.17 The E1 site was measured, and as a result, 12 clusters C1 were observed per unit area of ​​2 m in length and width. Only clusters C1 protruding 25 nm or more from the surface were measured. By adjusting the contrast in the AFM image, it is possible to adjust so that only clusters protruding 25 nm or more from the surface are output.

[0211] The density of cluster C1 converted into units based on the measurement results can be 1×10 -8 / cm 2 Up to 8×10 -6 / cm 2 If the density of cluster C1 is equal to or greater than 1×10 -8 / cm 2 , the contact area is relatively increased, so that the contact resistance between the second electrode is reduced.

[0212] Furthermore, if the density of cluster C1 is equal to or less than 8×10 -6 / cm 2 , the problem that light emitted from the active layer 126 is absorbed due to Ga included in a part of the clusters can be solved. Therefore, light output can be improved.

[0213] According to the embodiment, since the density of cluster C1 satisfies 1×10 -8 / cm 2 Up to 8×10 -6 / cm 2 , therefore, it is possible to prevent the light output from decreasing and reduce the contact resistance with the second electrode.

[0214] Reference Fig.18 , it can be seen that clusters cannot be observed on the surface of the GaN film. This is because as the density of the clusters becomes higher, a layer is formed. Therefore, it can be seen that if a GaN film is formed between the second conductive semiconductor layer and the second electrode, clusters are not formed on the contact surface. Therefore, when a GaN-based semiconductor material including aluminum, for example, an AlGaN material is arranged on the surface of the semiconductor structure, clusters C1 can be formed on the surface of the semiconductor structure.

[0215] Reference Fig.19 , it can be seen that even if the second conductive type semiconductor layer grows rapidly, the clusters cannot grow well. Therefore, it can be seen that even if the aluminum composition on the surface of the second conductive type semiconductor layer is controlled to be 1% to 10%, the cluster C1 is not formed when the growth rate is fast. For example, Fig.19 This is a photograph of the surface measured after P-AlGaN was grown at a rate of 0.06 nm / s.

[0216] That is, it can be determined that in order to form a plurality of clusters C1 in the second conductive type semiconductor layer 127, the aluminum composition in the contact layer should be 1% to 10%, and the growth rate of the contact layer needs to be sufficiently slow.

[0217] In an embodiment, the growth rate of the 2-1 conductive type semiconductor layer may be lower than the growth rates of the 2-2 conductive type semiconductor layer and the 2-3 conductive type semiconductor layer. Exemplarily, the ratio of the growth rate of the 2-2 conductive type semiconductor layer to the growth rate of the 2-1 conductive type semiconductor layer may be 1:0.2 to 1:0.8. If the growth rate ratio is less than 1:0.2, the growth rate of the 2-1 conductive type semiconductor layer becomes too slow, and therefore, Ga is etched at the high temperature of AlGaN growth, so that AlGaN with a high Al composition grows, thereby deteriorating the ohmic characteristics. If the growth rate ratio is greater than 1:0.8, the growth rate of the 2-1 conductive type semiconductor layer becomes too fast, resulting in a decrease in crystallinity. Fig. 20 is a conceptual diagram of a semiconductor device according to a third embodiment of the present invention, Fig.21a for Fig. 20 Floor plan, Figure 21b for Fig. 20 A magnified view of part A. Fig. 22 A plan view illustrating an interface between the second conductive type semiconductor layer and the second electrode.

[0218] Reference Fig. 20 The above-mentioned structure of the semiconductor structure 120 can be directly applied to the semiconductor structure 120 . The plurality of grooves 128 penetrate the second conductive semiconductor layer 127 and the active layer 126 and are arranged in a part of the first conductive semiconductor layer 124 .

[0219] The semiconductor device may include a side reflective portion Z1 disposed at an edge. The side reflective portion Z1 may be formed by protruding the second conductive layer 150, the first conductive layer 165, and the substrate 170 in the thickness direction (Y-axis direction). Fig.21a The side reflective portion Z1 may be arranged along the edge of the semiconductor device and in a manner of surrounding the semiconductor structure.

[0220] The second conductive layer 150 of the side reflective portion Z1 may protrude further than the active layer 126 and upwardly reflect the light L2 emitted from the active layer 124. Therefore, light emitted in the horizontal direction (X-axis direction) due to the TM mode at the outermost periphery can be reflected upwardly without forming an additional reflective layer.

[0221] The side reflector Z1 may have an inclination angle greater than 90 degrees and less than 145 degrees, which may be an angle formed by the second conductive layer 150 and the horizontal plane (XZ plane). If the angle is less than 90 degrees or greater than 145 degrees, the efficiency of upwardly reflecting light moving sideways may be reduced.

[0222] Reference Figure 21b, the second electrode 246 can directly contact the 2-1st conductivity type semiconductor layer 127a. As described above, the clusters are arranged on the surface of the 2-1st conductivity type semiconductor layer 127a, so that the contact area with the second electrode 246 can be increased.

[0223] The second electrode 246 may be deposited on the 2-1st conductive type semiconductor layer 127a. If the second electrode 246 is a metal oxide such as ITO, the 2-1st conductive type semiconductor layer 127a may be in contact with oxygen. Therefore, aluminum disposed on the surface of the 2-1st conductive type semiconductor layer 127a reacts with oxygen to form aluminum oxide. In addition, nitrides such as NO or oxides of Ga2O3 may also be formed.

[0224] Reference Fig. 22 Aluminum C2 can be observed at the interface between the second electrode 246 and the second conductive semiconductor layer 127a. The interface can be observed using a transmission electron microscope (TEM) or the like.

[0225] Fig.23 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention, Fig.24 is a plan view of a semiconductor device package according to an embodiment of the present invention, Fig.25 for Fig.24 A variation of .

[0226] Reference Fig.23 The semiconductor device package may include a body 2 formed with a groove 3 (opening portion), a semiconductor device 1 disposed on the body 2, and a pair of frames 5a, 5b arranged on the body 2 and electrically connected to the semiconductor device 1. The semiconductor device 1 may include all of the above-mentioned components.

[0227] The body 2 may include a material or coating that reflects ultraviolet light. The body 2 may be formed by stacking a plurality of layers 2a, 2b, 2c, 2d, and 2e. The plurality of layers 2a, 2b, 2c, 2d, and 2e may be the same material, or may include different materials. For example, the plurality of layers 2a, 2b, 2c, 2d, and 2e may include an aluminum material.

[0228] The groove 3 is formed to be wider as it is farther away from the semiconductor device, and a step 3 a may be formed on the inclined surface.

[0229] The light-transmitting layer 4 may cover the groove 3. The light-transmitting layer 4 may be made of glass, but is not limited thereto. The light-transmitting layer 4 may be made of any material that can effectively transmit ultraviolet light, and is not particularly limited. The interior of the groove 3 may be an empty space.

[0230] Reference Fig.24The semiconductor device 10 may be arranged on the first lead frame 5a and connected to the second lead frame 5b through leads. The second lead frame 5b may be arranged to surround the side of the first lead frame.

[0231] Reference Fig.25 The semiconductor device package may be provided with a plurality of semiconductor devices 10a, 10b, 10c, 10d. The lead frame may include a first lead frame 5a, a second lead frame 5b, a third lead frame 5c, a fourth lead frame 5d and a fifth lead frame 5e.

[0232] The first semiconductor device 10a may be arranged on the first lead frame 5a and connected to the second lead frame 5b through a lead. The second semiconductor device 10b may be arranged on the second lead frame 5b and connected to the third lead frame 5c through a lead. The third semiconductor device 10c may be arranged on the third lead frame 5c and connected to the fourth lead frame 5d through a lead. The fourth semiconductor device 10d may be arranged on the fourth lead frame 5d and connected to the fifth lead frame 5e through a lead.

[0233] The semiconductor device can be applied to various types of light source devices. For example, the light source device can include a sterilization device, a curing device, a lighting device, a display device, and a vehicle lamp. That is, the semiconductor device can be applied to various electronic devices that provide light in a manner of being arranged in a housing.

[0234] The sterilization device may include a semiconductor device according to an embodiment to sterilize a required area. The sterilization device may be applied to household appliances such as water purifiers, air conditioners, refrigerators, etc., but is not limited thereto. That is, the sterilization device may be applied to various products that need to be sterilized (e.g., medical devices).

[0235] Exemplarily, the water purifier may be equipped with a sterilization device according to an embodiment to sterilize the circulating water. The sterilization device may be arranged at the nozzle or outlet of the circulating water and irradiate ultraviolet rays. The sterilization device may include a waterproof structure.

[0236] The curing device may include a semiconductor device according to an embodiment to cure various liquids. Liquid may be the broadest concept including various materials that cure when irradiated with ultraviolet light. Exemplarily, the curing device may cure various types of resins. Alternatively, the curing device may be used to cure cosmetics, such as manicure.

[0237] The lighting device may include a light source module having a substrate and the semiconductor device of the present embodiment, a heat dissipation unit for dissipating heat of the light source module, and a power supply unit for processing or converting an electrical signal provided from the outside to provide to the light source module. In addition, the lighting device may include a lamp, a headlamp, a street lamp, etc.

[0238] The display device may include a bottom cover, a reflective plate, a light emitting module, a light guide plate, an optical sheet, a display panel, an image signal output circuit, and a color filter. The bottom cover, the reflective plate, the light emitting module, the light guide plate, and the optical sheet may constitute a backlight unit.

[0239] The reflective plate may be arranged on the bottom cover, and the light emitting module may emit light. The light guide plate may be arranged in front of the reflective plate and guide the light emitted from the light emitting module forward, the optical sheet may include a prism sheet and the like and be arranged in front of the light guide plate. The display panel may be arranged in front of the optical sheet, the image signal output circuit provides an image signal to the display panel, and the color filter may be arranged in front of the display panel.

[0240] When the semiconductor device is used as a backlight unit of a display device, the semiconductor device may be used as an edge type backlight unit, or may be used as a direct type backlight unit.

[0241] In addition to the above-mentioned light emitting diodes, the semiconductor device may be a laser diode.

[0242] Similar to the light-emitting element, the laser diode may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer of the above structure. Moreover, the laser diode uses an electroluminescent phenomenon that emits light when a current is supplied after a p-type first conductive semiconductor and an n-type second conductive semiconductor are joined, but there are differences in the direction and phase of the light emission. That is, the laser diode can emit light having a specific wavelength (monochromatic light beam) in the same phase and in the same direction by using a phenomenon called stimulated emission and a constructive interference phenomenon, and can be used for optical communications, medical equipment, and semiconductor process equipment by virtue of these characteristics.

[0243] As the light receiving element, a photodetector as a transducer that detects light and converts the intensity of light into an electrical signal can be exemplified. Examples of photodetectors include photocells (silicon, selenium), photoelectric elements (cadmium sulfide, cadmium selenide), photodiodes (for example, PDs having a peak wavelength in a visible blind spectral region or a real blind spectral region), phototransistors, photomultiplier tubes, phototubes (vacuum, gas-filled), infrared (Infra-Red, IR) detectors, etc., but the embodiments are not limited thereto.

[0244] And, generally, semiconductor devices such as photodetectors can be manufactured using direct bandgap semiconductors with excellent light conversion efficiency. Alternatively, photodetectors have a variety of structures, the most common structures of which include a pinned photodetector using a pn junction, a Schottky photodetector using a Schottky junction, and a metal semiconductor metal (MSM) type detector, etc.

[0245] Similar to the light-emitting element, the photodiode may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer having the above structure, and may be composed of a pn junction or a pin structure. The photodiode operates by applying a reverse bias or a zero bias. When light is incident on the photodiode, electrons and holes are generated and current flows. At this time, the magnitude of the current may be proportional to the intensity of the light incident on the photodiode.

[0246] A photovoltaic cell or solar cell is a photodiode that can convert light into electric current. Similar to a light emitting element, a solar cell may include a first conductive type semiconductor layer, an active layer, and a second conductive type semiconductor layer having the above structure.

[0247] Furthermore, it can be used as a rectifier of an electronic circuit by using the rectification characteristics of a general diode of a pn junction, or can be applied to an oscillation circuit, etc. by being applied to an ultra-high wave circuit.

[0248] Furthermore, the semiconductor device is not limited to semiconductors, and may include metal materials depending on the situation. For example, a semiconductor device such as a light-receiving element is implemented by using any one selected from Ag, Al, Au, In, Ga, N, Zn, Se, P, or As, or by using a semiconductor material doped with a p-type or n-type dopant or an intrinsic semiconductor material.

[0249] Although embodiments have been described with reference to a number of illustrative embodiments of the present invention, it will be appreciated that within the spirit and scope of the principles of the present invention, a variety of other modifications and embodiments may be devised by those skilled in the art. More specifically, various changes and modifications may be made to the components and / or arrangements of the main combination arrangement within the scope of the present invention, the drawings, and the appended claims. In addition to changes and modifications to the components and / or arrangements, alternative uses will also be apparent to those skilled in the art.

Claims

1. A semiconductor device, characterized in that: include: A semiconductor structure comprises a first conductive type semiconductor layer, a second conductive type semiconductor layer and an active layer arranged between the first conductive type semiconductor layer and the second conductive type semiconductor layer, Wherein, the active layer includes a plurality of barrier layers and a plurality of well layers, The barrier layer, the well layer, the first conductive type semiconductor layer and the second conductive type semiconductor layer include aluminum, The second conductive type semiconductor layer includes a 2-2 conductive type semiconductor layer and a 2-1 conductive type semiconductor layer disposed on the 2-2 conductive type semiconductor layer. The aluminum composition of the 2-1 conductive type semiconductor layer decreases at a first slope as it moves away from the active layer. The aluminum composition of the 2-2 conductive type semiconductor layer decreases at a second slope as it moves away from the active layer. The first slope is greater than the second slope, The aluminum composition of the 2-1 conductive type semiconductor layer is less than the aluminum composition of the well layer, and The aluminum composition of the 2-2 conductive type semiconductor layer is greater than the aluminum composition of the well layer.

2. The semiconductor device according to claim 1, wherein: The aluminum composition of the 2-1 conductive type semiconductor layer is greater than 1% and less than 50%, and the thickness of the 2-1 conductive type semiconductor layer is greater than 1 nm and less than 30 nm.

3. The semiconductor device according to claim 1, wherein: The thickness of the 2-1 conductive type semiconductor layer is smaller than the thickness of the 2-2 conductive type semiconductor layer.

4. The semiconductor device according to claim 1, wherein: The aluminum composition of the 2-2 conductive type semiconductor layer is greater than 40% and less than 80%, and the thickness of the 2-2 conductive type semiconductor layer is greater than 10 nm and less than 200 nm.

5. The semiconductor device according to claim 1, wherein: Also includes: a plurality of grooves, the plurality of grooves passing through the second conductive type semiconductor layer and the active layer and arranged in a portion of the first conductive type semiconductor layer; A first electrode, arranged in the groove and electrically connected to the first conductive type semiconductor layer; and The second electrode is electrically connected to the second conductive type semiconductor layer.

6. The semiconductor device according to claim 5, characterized in that The 2-1 conductive type semiconductor layer includes a surface layer in contact with the second electrode, and an aluminum composition of the surface layer is 1% to 20%.

7. The semiconductor device according to claim 3, characterized in that A thickness ratio of the 2-1st conductivity type semiconductor layer to the 2-2nd conductivity type semiconductor layer is 1:1.5 to 1:

20.

8. The semiconductor device according to claim 5, characterized in that A surface of the second conductive type semiconductor layer in contact with the second electrode includes a plurality of protruding clusters.

9. The semiconductor device according to claim 5, characterized in that The distance between the top of the groove and the top of the semiconductor structure is 1㎛ to 4㎛.

10. The semiconductor device according to claim 8, characterized in that The surface of the second conductive semiconductor layer includes 2 There are 1 to 8 clusters arranged in a region, and the density of the clusters is 1×10 -8 / cm 2 Up to 8×10 -6 / cm 2 .

11. The semiconductor device according to claim 8, characterized in that Each of the clusters is formed due to the lattice mismatch between aluminum and gallium.

12. The semiconductor device according to claim 8, characterized in that The aluminum composition on the surface of the second conductive type semiconductor layer is 1% to 10%.

13. A semiconductor device package, comprising: ontology; as well as The semiconductor device according to any one of claims 1 to 12, wherein the semiconductor device is arranged in the body.

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