Semiconductor device and semiconductor device package

Abstract

An embodiment discloses a semiconductor device, comprising: a substrate; a light-emitting structure, comprising a first conductive semiconductor layer, a second conductive semiconductor layer, an active layer, and a plurality of grooves passing through the second conductive semiconductor layer and the active layer, and a portion of the first conductive semiconductor layer in a thickness direction of the light-emitting structure; a first electrode, electrically connected to the first conductive semiconductor layer; a second electrode, electrically connected to the second conductive semiconductor layer; a first conductive layer, electrically connected to the first electrode; a second conductive layer, electrically connected to the second electrode, the second conductive semiconductor layer comprising a 1‑1 surface arranged between two grooves most adjacent in a first direction, the 1‑1 surface comprising a first portion on which a plurality of second electrodes spaced apart from each other in the first direction are arranged and a second portion arranged between the plurality of second electrodes, the second conductive layer being arranged between the first portion and the second portion, and a width ratio of the second portion to the first portion in the first direction is in the range of 1:0.7 to 1:5.

Description

[0001] This application is a divisional application of an invention patent application with an international application date of June 20, 2017, an international application number of PCT / KR2017 / 006473, an application number of 201780038448.4 entering the Chinese national phase, and an invention name of “Semiconductor Device”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of Korean Patent Application No. 10-2016-0076586 filed in Korea on June 20, 2016, Korean Patent Application No. 10-2016-0087728 filed in Korea on July 11, 2016, and Korean Patent Application No. 10-2016-0115894 filed in Korea on September 8, 2016, which are hereby incorporated by reference in their entirety. Technical Field

[0004] Embodiments relate to semiconductor devices. Background Art

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

[0006] In particular, due to the development of thin film growth technology and device materials, light-emitting devices using III-V or II-VI compound semiconductors or light-emitting devices such as laser diodes can achieve various colors such as red, green, blue and ultraviolet, and can implement effective white light by using fluorescent materials or combined colors. Compared with traditional light sources such as fluorescent lamps and incandescent lamps, these light-emitting devices also have the advantages of low power consumption, semi-permanent life, fast response time, safety, and environmental protection.

[0007] In addition, when light-receiving devices such as photodetectors or solar cells are manufactured using III-V or II-VI compound semiconductors, photocurrent can be generated by the absorption of light in various wavelength ranges through the development of device materials. Therefore, light can be used in various wavelength ranges from gamma rays to radio wavelength regions. Moreover, light-receiving devices have the advantages of fast response time, stability, environmental protection, and easy adjustment of device materials, and can be easily used in power control or microwave circuits or communication modules.

[0008] Therefore, semiconductor devices are widely used in transmission modules of optical communication devices, light-emitting diode backlights that replace cold cathode fluorescent lamps (CCFL) that form the backlight source of liquid crystal display devices (LCDs), white light-emitting diode lamps that replace fluorescent bulbs or incandescent bulbs, car headlights, traffic lights, and sensors for detecting gas or fire, etc. In addition, semiconductor devices can also be widely used in high-frequency application circuits or other power control devices, and even communication modules.

[0009] In particular, a light emitting device emitting light in the ultraviolet wavelength range may be used for curing, medical treatment, and sterilization purposes due to its curing or sterilizing effect.

[0010] However, light-emitting devices that emit ultraviolet wavelengths have a high aluminum component, so current cannot spread well in the semiconductor layer, which results in a decrease in light output power and an increase in operating voltage. Summary of the invention

[0011] Technical issues

[0012] Embodiments provide a semiconductor device with enhanced light output power.

[0013] Another embodiment provides a semiconductor device capable of having an adjustable orientation angle.

[0014] Another embodiment provides a semiconductor device having a low operating voltage.

[0015] Technical Solution

[0016] A semiconductor device according to an embodiment includes: a substrate; a light emitting structure including, in a thickness direction of the light emitting structure, a first conductive semiconductor layer, a second conductive semiconductor layer, an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer, and a plurality of grooves passing through the second conductive semiconductor layer and the active layer, and a portion of the first conductive semiconductor layer; a first electrode electrically connected to the first conductive semiconductor layer by contacting the first conductive semiconductor layer disposed on top surfaces of the plurality of grooves; a second electrode electrically connected to the second conductive semiconductor layer by contacting the second conductive semiconductor layer; a first conductive layer electrically connected to the first electrode; and a second conductive layer electrically connected to the second electrode, wherein the second conductive semiconductor layer includes a 1-1 surface disposed between two grooves that are most adjacent in a first direction, and the first direction is a direction perpendicular to the thickness direction of the light emitting structure, wherein the 1-1 surface includes a first portion provided with a plurality of second electrodes spaced apart from each other in the first direction and a second portion disposed between the plurality of second electrodes, wherein the second conductive layer is disposed between the first portion and the second portion, and wherein a width ratio of the second portion to the first portion in the first direction is in a range of 1:0.7 to 1:5.

[0017] Optionally, a width of the second portion in the first direction is in a range of 5 μm to 16 μm.

[0018] Optionally, the second portion includes a point corresponding to 1 / 2 of the width of the 1-1 surface in the first direction.

[0019] Optionally, the entire width of the first portion in the first direction is in the range of 12 μm to 24 μm.

[0020] Optionally, the second conductive layer includes a reflective groove arranged in the second portion.

[0021] Optionally, a light-transmitting layer is provided in the reflecting groove.

[0022] Optionally, it includes a sub-groove arranged in the second portion and a sub-reflection layer arranged in the sub-groove, wherein the sub-reflection layer contains aluminum, and wherein the sub-reflection layer is electrically connected to the second electrode.

[0023] Optionally, the second conductive semiconductor layer has a first surface comprising AlGaN.

[0024] Optionally, the second conductive layer includes: a first intermediate layer containing at least one of chromium (Cr), titanium (Ti) and nickel (Ni); and a reflective layer containing aluminum.

[0025] A semiconductor device package according to an embodiment includes a body, and the semiconductor device provided according to the embodiment; the semiconductor device is disposed in the body.

[0026] Beneficial effects of the present invention

[0027] According to the embodiments, the optical output power of a semiconductor device can be improved.

[0028] The orientation angle of the semiconductor device can also be adjusted.

[0029] It can also reduce the operating voltage of semiconductor devices.

[0030] It will be easily understood that although the embodiments of the present invention have been described in detail, the various advantageous advantages and effects of the present invention are not limited to the above description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a conceptual diagram of a semiconductor device according to a first embodiment of the present invention.

[0032] Figure 2 yes Figure 1 Magnified view of part A.

[0033] Figure 3 is a plan view of a semiconductor device according to a first embodiment of the present invention.

[0034] Figure 4 is a plan view of a semiconductor device according to a second embodiment of the present invention.

[0035] Figure 5 is a plan view of a semiconductor device according to a third embodiment of the present invention.

[0036] Figure 6 is a graph obtained by measuring the optical output power of the semiconductor devices according to the first to third embodiments.

[0037] Figure 7 is a graph obtained by measuring the operating voltage of the semiconductor device according to the first to third embodiments.

[0038] Figure 8 is a plan view of a semiconductor device according to a fourth embodiment of the present invention.

[0039] Fig. 9 is a plan view of a semiconductor device according to a fifth embodiment of the present invention.

[0040] Fig.10 is a plan view of a semiconductor device according to a sixth embodiment of the present invention.

[0041] Fig.11 is a plan view of a semiconductor device according to a seventh embodiment of the present invention.

[0042] Fig.12 is a graph obtained by measuring the optical output power of the semiconductor devices according to the fourth to seventh embodiments.

[0043] Fig.13 is a graph obtained by measuring the operating voltage of the semiconductor device according to the fourth to seventh embodiments.

[0044] Fig.14 is a plan view of a semiconductor device according to an eighth embodiment of the present invention.

[0045] Fig.15 is a plan view of a semiconductor device according to a ninth embodiment of the present invention.

[0046] Fig.16 is a plan view of a semiconductor device according to a tenth embodiment of the present invention.

[0047] Fig.17 is a plan view of a semiconductor device according to an eleventh embodiment of the present invention.

[0048] Fig.18 is a plan view of a semiconductor device according to a twelfth embodiment of the present invention.

[0049] Fig.19 is a graph obtained by measuring the optical output powers of the semiconductor devices according to the ninth to twelfth embodiments.

[0050] Fig. 20 is a graph obtained by measuring the operating voltages of the semiconductor devices according to the ninth to twelfth embodiments.

[0051] Fig.21 is a conceptual diagram of a light emitting structure according to an embodiment of the present invention.

[0052] Fig. 22 The graph is obtained by measuring the aluminum component of the light-emitting structure.

[0053] Fig.23a and 23b is a view showing a configuration in which light output power is enhanced according to a change in the number of grooves.

[0054] Fig.24 is a conceptual diagram of a semiconductor device according to a thirteenth embodiment of the present invention.

[0055] Fig.25 yes Fig.24 Floor plan.

[0056] Fig.26 is along Fig.25 AA cross-sectional view.

[0057] Fig. 27 is a diagram showing the configuration of the second conductive layer.

[0058] Fig.28 yes Fig. 27 The first modification example.

[0059] Fig.29 yes Fig. 27 The second modification example.

[0060] Fig.30 is a conceptual diagram of a semiconductor device according to a fourteenth embodiment of the present invention.

[0061] Fig.31 yes Fig.30 Floor plan.

[0062] Fig.32 yes Fig.31 An enlarged view of part B-1.

[0063] Fig.33 yes Fig.31 An enlarged view of part B-2.

[0064] Fig.34 is along Fig.32 A cross-sectional view of BB.

[0065] Fig.35 yes Fig.34 The first modification example.

[0066] Fig.36a and Fig.36b yes Fig.34 The second modification example.

[0067] Fig.37 yes Fig.33 The third modification example.

[0068] Fig.38 is a conceptual diagram of a semiconductor device according to a fifteenth embodiment of the present invention.

[0069] Fig.39 yes Fig.38 Floor plan.

[0070] Fig.40 is along Fig.39 Cross-sectional view taken from CC.

[0071] Fig.41 yes Fig.40 The first modification example.

[0072] Fig.42 yes Fig.40 The second modification example.

[0073] Fig.43 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention.

[0074] Fig.44 is a plan view of a semiconductor device according to a sixteenth embodiment.

[0075] Fig.45 is along Fig.44 A cross-sectional view of the semiconductor device taken along line H-H'.

[0076] Fig.46 It is shown Fig.45 Detailed view of a part of.

[0077] Figure 47 to Figure 49 are detailed diagrams showing a portion of the semiconductor device according to seventeenth to nineteenth embodiments.

[0078] Fig.50 is a plan view of a semiconductor device according to a twentieth embodiment.

[0079] Fig.51 is along Fig.50 A cross-sectional view of the semiconductor device taken along line K-K'.

[0080] Fig.52 is a diagram showing a package in which a semiconductor device is provided.

[0081] Fig.53 is a plan view of a semiconductor device package according to an embodiment of the present invention.

[0082] Fig.54 yes Fig.53 Modification example. DETAILED DESCRIPTION

[0083] The following embodiments may be modified or combined with each other, and the scope of the present invention is not limited to these embodiments.

[0084] Even if the contents described in a specific embodiment are not described in other embodiments, the contents described in the specific embodiment can be understood as contents related to the other embodiments unless otherwise stated or denied.

[0085] For example, if the features of element A are described in a specific embodiment and the features of element B are described in other embodiments, even if the embodiment in which element A and element B are combined is not explicitly described, the embodiment in which element A and element B are combined should be understood to be within the scope of the present invention unless otherwise stated or denied.

[0086] In the description of the embodiments, when an element is referred to as being "above" or "below" another element, the two elements may be directly in contact with each other, or one or more elements may be present between the two elements. In addition, the terms "above" or "below" used herein may indicate an upward direction as well as a downward direction relative to an element.

[0087] Hereinafter, various exemplary embodiments are described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them.

[0088] Figure 1 is a conceptual diagram of a semiconductor device according to a first embodiment of the present invention. Figure 2 yes Figure 1 Enlarged view of part A.

[0089] Reference Figure 1 According to the embodiment, the semiconductor device includes: a light emitting structure 120 including a first conductive semiconductor layer 122, a second conductive semiconductor layer 126 and an active layer 124; a first electrode 142 electrically connected to the first conductive semiconductor layer 122; and a second electrode 246 electrically connected to the second conductive semiconductor layer 126.

[0090] The first conductive semiconductor layer 122, the active layer 124, and the second conductive semiconductor layer 126 may be disposed along a first direction (Y direction). Here, the first direction (Y direction, i.e., the thickness direction of each layer) is defined as a vertical direction, and a second direction (X direction) perpendicular to the first direction (Y direction) is defined as a horizontal direction.

[0091] The light emitting structure 120 according to the embodiment may output light of an ultraviolet wavelength. For example, the light emitting structure 120 may output light of a near ultraviolet wavelength (UV-A), a far ultraviolet wavelength (UV-B), or a deep ultraviolet wavelength (UV-C). The wavelength range may be determined by the aluminum component of the light emitting structure 120.

[0092] For example, near ultraviolet wavelength light (UV-A) may have a wavelength of 320nm to 420nm, far ultraviolet wavelength light (UV-B) may have a wavelength of 280nm to 320nm, and deep ultraviolet wavelength light (UV-C) may have a wavelength of 100nm to 280nm.

[0093] The light emitting structure 120 may include a plurality of grooves 128 extending to a portion of the first conductive semiconductor layer 122 through the second conductive semiconductor layer 126 and the active layer 124 .

[0094] The first electrode 142 may be disposed on the top of each groove 128 and electrically connected to the first conductive semiconductor layer 122. The second electrode 246 may be formed under the second conductive semiconductor layer 126. The second electrode 246 may be separated by the grooves 128.

[0095] Each of the first electrode 142 and the second electrode 246 may be an ohmic electrode. Each of the first electrode 142 and the second electrode 246 may be made of at least one of 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 tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), aluminum nitride (IZON), Al-Ga ZnO (AGZO), In-Ga ZnO (IGZO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au, Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, and Hf, but is not limited thereto.

[0096] The second electrode pad 166 may be disposed in an edge region of the semiconductor device. The second electrode pad 166 may have a concave central portion and thus have a top surface including a concave portion and a convex portion. A wire (not shown) may be bonded to the concave portion of the top surface. Therefore, due to the increased bonding area, the second electrode pad 166 may be securely bonded to the wire.

[0097] The second electrode pad 166 may reflect light. Therefore, as the second electrode pad 166 is closer to the light emitting structure 120, the second electrode pad 166 may have higher light extraction efficiency.

[0098] The shortest distance between the second electrode pad 166 and the light emitting structure 120 may be in the range of 5 μm to 30 μm. When the shortest distance is less than 10 μm, it is difficult to ensure a process margin. When the shortest distance is greater than 30 μm, the arrangement area of ​​the second electrode pad 166 in the entire device increases, so the area of ​​the light emitting layer 24 may decrease, and the amount of light may decrease.

[0099] The convex portion of the second electrode pad 166 may be higher than the active layer 126. Therefore, the second electrode pad 166 may improve light extraction efficiency and control an orientation angle by reflecting light emitted from the active layer 126 in a horizontal direction upward to the device.

[0100] The first insulating layer 131 is partially opened under the second electrode pad 166 so that the second conductive layer 150 and the second electrode 246 can be electrically connected to each other. The passivation layer 180 may be formed on the top and side of the light emitting structure 120. The passivation layer 180 may contact the first insulating layer 131 in a region adjacent to the second electrode 246 or in a lower portion of the second electrode 246.

[0101] The opening of the first insulating layer 131 where the second electrode 246 contacts the second conductive layer 150 may have a width d22 ranging from, for example, 40 μm to 90 μm. When the width d22 is less than 40 μm, the operating voltage may increase. When the width d22 is greater than 90 μm, it may be difficult to ensure a process margin for preventing the second conductive layer 150 from being exposed. When the second conductive layer 150 is exposed from the second electrode 246, device reliability may be reduced. Therefore, the width d22 may preferably be in the range of 60% to 95% of the entire width of the second electrode 246.

[0102] Reference Figure 2 When the aluminum component of the light emitting structure 120 increases, the current spread characteristics in the light emitting structure 120 may be deteriorated. Also, the active layer 124 has a large amount of light emitted to the side (TM mode) compared to a GaN-based blue light emitting device. The TM mode may be performed by an ultraviolet semiconductor device.

[0103] According to the embodiment, the ultraviolet semiconductor device may form a greater number of grooves 128 compared to a typical GaN semiconductor, and then the first electrode 142 may be disposed on each groove 128 .

[0104] The first insulating layer 131 may electrically insulate the first electrode 142 from the active layer 126 and the second conductive semiconductor layer 127. Also, the first insulating layer 131 may electrically insulate the second electrode 246 and the second conductive layer 150 from the first conductive layer 165.

[0105] 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 N y , Al2O3, TiO2, and AlN. The first insulating layer 131 may be formed as a single layer or multiple layers. For example, 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.

[0106] When the first insulating layer 131 has an insulating function, the first insulating layer 131 may reflect light L1 horizontally emitted from the active layer 124 upward, thereby improving light extraction efficiency. As described below, as the number of grooves 128 increases, light extraction efficiency may increase.

[0107] The first electrode 142 may have a diameter W3 ranging from 24 μm to 50 μm. When this range is satisfied, current diffusion may be facilitated, and a large number of first electrodes 142 may be arranged.

[0108] When the diameter W3 of the first electrode 142 is less than 24 μm, the current injected into the first conductive semiconductor layer 122 may be insufficient. When the diameter W3 is greater than 50 μm, the number of first electrodes 142 disposed in the region of the first conductive semiconductor layer 122 may be insufficient, thus being disadvantageous in terms of current spreading characteristics.

[0109] Each of the grooves 128 may have a diameter W1 ranging from 38 μm to 60 μm. The diameter W1 of the groove 128 may be defined as a maximum diameter formed at the bottom of the second conductive semiconductor layer 126 .

[0110] When the diameter W1 of each groove 128 is less than 38 μm, it is difficult to ensure a process margin for forming the first electrode 142 disposed in the groove 128. When the diameter W1 is greater than 60 μm, the removal volume of the light emitting layer 124 adjacent to the first electrode 142 increases, thereby possibly reducing light emitting efficiency.

[0111] The groove 128 may have a top surface 143 having a diameter W2 in the range of 30 μm to 58 μm.

[0112] For example, the diameter W1 of each groove 128 may be 56 μm, and the diameter W2 of the top surface may be 54 μm. Each groove 128 may have an inclination angle θ5 ranging from 70 degrees to 90 degrees. When this range is satisfied, it may be advantageous to form the first electrode 142 on the top surface, and a large number of grooves 128 may be formed.

[0113] When the inclination angle θ5 is less than 70 degrees, the removal volume of the light emitting layer 124 increases, and thus the light emitting efficiency may be reduced. By utilizing the inclination angle θ5 of each groove 128, the area of ​​the first electrode 142 and the area of ​​the second electrode 246 may be adjusted.

[0114] The thickness d2 of the first electrode 142 may be smaller than the thickness d3 of the first insulating layer 131 , and the first electrode 142 and the first insulating layer 131 may have a separation distance d4 ranging from 0 μm to 4 μm.

[0115] When the thickness d2 of the first electrode 142 is less than the thickness d3 of the first insulating layer 131, problems such as separation or cracks caused by a reduction in step coverage characteristics caused when the first conductive layer 165 is provided can be solved. Also, since the first electrode 142 and the first insulating layer 131 have a spacing distance d4, a gap filling characteristic of the second insulating layer 132 can be improved.

[0116] The spacing distance d4 between the first electrode 142 and the first insulating layer 131 may be in the range of 0 μm to 4 μm.

[0117] When the spacing distance d4 between the first electrode 142 and the first insulating layer 131 is greater than 4 μm, the width of the first insulating layer 131 disposed on each groove 128 is reduced. Therefore, it is difficult to ensure a process margin, and thus reliability may be reduced. Moreover, the width W3 of the first electrode 142 is reduced so much that the operating voltage characteristics may be degraded. The top surface 143 of each groove 128 may include a first region d5, in which the first insulating layer 131 contacts the first conductive semiconductor layer 122, a second region d4, in which the second insulating layer 132 contacts the first conductive semiconductor layer 122, and a third region d6, in which the first electrode 142 contacts the first conductive semiconductor layer 122. The third region d6 may be equal to the width W of the first electrode 142.

[0118] When the first insulating layer 142 and the second insulating layer 132 are made of the same material, the first insulating layer 142 and the second insulating layer 132 may not be distinguished by physical and / or chemical composition. In this case, the sum of the width of the first region d5 and the width of the second region d4 may be defined as the width of the first region d5 or the width of the second region d4.

[0119] As the first region d5 becomes wider, the third region d6 may become narrower, and as the first region d5 becomes wider, the third region d6 may become wider.

[0120] The width of the first region d5 may be in the range of 11 μm to 28 μm. When the width is less than 11 μm, it is difficult to ensure process margin, so device reliability may be reduced. When the width is greater than 28 μm, the width W3 of the first electrode 142 is reduced so much that electrical characteristics may be degraded.

[0121] The width of the third region d6 can be determined by adjusting the widths of the first region d5 and the second region d4. In order to evenly diffuse current on the device and optimize current injection, the width of each groove 128 can be freely designed within the above range.

[0122] In addition, the area of ​​each groove 128 can be determined by adjusting the width of the first region s5, the second region d4, and the third region d6. When the area of ​​each groove 128 increases, the setting area of ​​the second electrode 246 decreases. Therefore, the ratio of the first electrode 142 to the second electrode 246 can be determined, and the width of each groove 128 can be freely designed within the above range to optimize the current density by matching the density of electrons and holes.

[0123] The second electrode 246 may be thinner than the first insulating layer 131 .

[0124] The second electrode 246 may be spaced apart from the first insulating layer 131 by a first spacing distance S2, and the first spacing distance S2 ranges from 1 μm to 4 μm. When the first spacing distance S4 is less than 1 μm, it is difficult to ensure a process margin, and thus reliability may be reduced. When the spacing distance S2 is greater than 4 μm, the arrangement area of ​​the second electrode 246 is too small so that the operating voltage may increase.

[0125] The second conductive layer 150 may cover the second electrode 246. Therefore, the second electrode pad 166, the second conductive layer 150, and the second electrode 246 may form one electrical path.

[0126] The second conductive layer 150 may completely surround the second electrode 246 and may be in contact with the side surface and the top surface of the first insulating layer 131. The second conductive layer 150 may be made of a material having a high adhesive strength with the first insulating layer 131, and may also be made of at least one material selected from the group consisting of Cr, Al, Ti, Ni, and Au, or an alloy thereof. The second conductive layer 150 may be formed as a single layer or a multilayer.

[0127] When the second conductive layer 150 contacts the side and top surfaces of the first insulating layer 131, thermal and electrical reliability of the second electrode 246 may be improved. Also, the second conductive layer 150 may have a reflective function for reflecting light emitted from a gap between the first insulating layer 131 and the second electrode 246 upward.

[0128] The second conductive layer 150 may be disposed at a second spacing distance between the first insulating layer 131 and the second electrode 246. The second conductive layer 150 may be disposed in contact with side and top surfaces of the second electrode 246 and the first insulating layer 131 at the second spacing distance.

[0129] Also, a region where the second conductive layer 150 contacts the second conductive semiconductor layer 126 to form a Schottky junction may be within the second spacing distance. By forming the Schottky junction, current diffusion may be facilitated.

[0130] The second insulating layer 132 may electrically insulate the second electrode 246 and the second conductive layer 150 from the first conductive layer 165. The first conductive layer 165 may extend into the groove formed on the second insulating layer 132 and may be electrically connected to the first electrode 142.

[0131] The first insulating layer 131 may have a smaller thickness than the second insulating layer 132. For example, the thickness of the first insulating layer 131 may be in the range of 3,000 angstroms to 7,000 angstroms. When the thickness is less than 3,000 angstroms, electrical reliability may be reduced. When the thickness is greater than 7,000 angstroms and the second conductive layer 150 is disposed on the top surface and the side surface of the first insulating layer 131, the second conductive layer 150 may have poor step coverage characteristics, thereby causing separation or cracks. When separation or cracks are caused, electrical reliability may be reduced or light extraction efficiency may be reduced.

[0132] The thickness of the second insulating layer 132 may be in the range of 4,000 angstroms to 10,000 angstroms. When the thickness is less than 4,000 angstroms, electrical reliability may deteriorate when the device is operating. When the thickness is greater than 10,000 angstroms, reliability may be reduced due to pressure or thermal stress applied to the device when the device is manufactured, and the cost of the device may also increase due to a long process time. The thickness of the first insulating layer 131 and the second insulating layer 132 is not limited thereto.

[0133] The first conductive semiconductor layer 122 may be made of a group III-V or group II-VI compound semiconductor. Also, the first conductive semiconductor layer 122 may be doped with a first dopant. The first conductive semiconductor layer 122 may be made of a semiconductor selected from the group having the empirical formula In x1 Al y1 Ga 1-x1-y1 The first conductive semiconductor layer 122 may be made of a material selected from semiconductor materials having a value of N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1), for example, GaN, AlGaN, InGaN, InAlGaN, etc. Moreover, the first dopant may be an n-type dopant such as Si, Ge, Sn, Se, and Te. When the first dopant is an n-type dopant, the first conductive semiconductor layer 122 doped with the first dopant may be an n-type semiconductor layer.

[0134] The first conductive semiconductor layer 122 may have a low resistance layer 122a having a relatively low aluminum composition and a high resistance layer 122b having a relatively high aluminum composition. The aluminum composition of the high resistance layer 122b may be in the range of 60% to 70%, and the aluminum composition of the low resistance layer 122a may be in the range of 40% to 50%. The low resistance layer 122a may be disposed adjacent to the active layer 124.

[0135] The first electrode 142 may be disposed in the low resistance layer 122a. That is, preferably, the groove 128 is formed in the low resistance layer 122a. This is because the high resistance layer 122b has a high aluminum component and a relatively low current diffusion characteristic. Therefore, the first electrode 142 may contact the low resistance layer 122a in each groove 128 and thus form an ohmic contact, and the light emitted to the high resistance layer 122b is not absorbed by the high resistance layer 122b, so that the light emitting efficiency may be improved.

[0136] The active layer 124 is a layer in which electrons (or holes) injected through the first conductive semiconductor layer 122 are combined with holes (or electrons) injected through the second conductive semiconductor layer 126. Due to the recombination between the electrons and the holes, the active layer 124 may be transformed into a lower energy level and generate light having a wavelength corresponding to the transformation.

[0137] The active layer 124 may have, but is not limited to, any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure. The active layer may contain Al.

[0138] The second conductive semiconductor layer 126 may be formed on the active layer 124 and may be made of a group III-V or group II-VI compound semiconductor. Also, the second conductive semiconductor layer 127 may be doped with a second dopant. The second conductive semiconductor layer 126 may be made of a semiconductor having an empirical formula of In x5 Al y2 Ga 1-x5-y2 The second conductive semiconductor layer 126 doped with the second dopant may be made of a semiconductor material of N (0≤x5≤1, 0≤y2≤1, and 0≤x5+y2≤1) or a material selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, and Ba, the second conductive semiconductor layer 126 doped with the second dopant may be a p-type semiconductor layer.

[0139] When the second conductive semiconductor layer 126 is made of AlGaN, hole injection may not be convenient due to low conductivity. Therefore, GaN having relatively high conductivity and having the same polarity as the second conductive semiconductor layer 126 may be provided on the bottom of the second conductive semiconductor layer 126. However, the present invention is not limited thereto. As described below, the surface layer of the second conductive semiconductor layer 126 in contact with the second electrode may be made of AlGaN.

[0140] Refer again Figure 1 , the second conductive layer 150 may electrically connect the second electrode 246 to the second electrode pad 166 .

[0141] The second conductive layer 150 may be made of at least one material selected from the group consisting of Cr, Al, Ti, Ni, and Au, or an alloy thereof. Also, the second conductive layer 150 may be formed as a single layer or a multilayer.

[0142] The first conductive layer 165 and the junction layer 160 may be provided according to the shape of the bottom surface of the light emitting structure 120 and the shape of the groove 128. The first conductive layer 165 may be made of a material having a high reflectivity. For example, the first conductive layer 165 may include aluminum. When the first conductive layer 165 includes aluminum, the first conductive layer 165 may be used to reflect light emitted from the active layer 124 upward toward the substrate 170, thereby improving light extraction efficiency.

[0143] The junction layer 160 may include a conductive material. For example, the junction 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.

[0144] The substrate 170 may be made of a conductive material. For example, the substrate 170 may include a metal or a semiconductor material. The substrate 170 may be made of a metal having high electrical conductivity and / or thermal conductivity. In this case, the heat generated during operation of the semiconductor device may be quickly released to the outside.

[0145] The substrate 170 may include a material selected from the group consisting of silicon, molybdenum, tungsten, copper, and aluminum, or an alloy thereof.

[0146] The second electrode pad 166 may be made of a conductive material. The second electrode pad 166 may have a single layer or multilayer structure and may contain titanium Ti, nickel Ni, silver Ag, and gold Au. For example, the second electrode pad 166 may have a structure of Ti / Ni / Ti / Ni / Ti / Au.

[0147] The passivation layer 180 may be disposed on the top surface and the side surface of the light emitting structure 120. The passivation layer 180 may have a thickness ranging from 2,000 angstroms to 5,000 angstroms. When the thickness is less than 2,000 angstroms, the thickness is insufficient to protect the device from external moisture or foreign substances, and thus the optical and electrical reliability of the device may be reduced. When the thickness is greater than 5,000 angstroms, the optical and electrical reliability may be reduced due to increased stress applied to the device, or the device cost may increase due to a long process time.

[0148] A square wave pattern may be formed on the top of the light emitting structure 120. The square wave pattern may improve the extraction efficiency of light emitted from the light emitting structure 120. The square wave pattern may have different average heights depending on the wavelength of ultraviolet light. For UV-C, the average height ranges from 300 nm to 800 nm. When the average height is in the range of 500 nm to 600 nm, the light extraction efficiency may be improved.

[0149] Figure 3 is a plan view of a semiconductor device according to a first embodiment of the present invention. Figure 4 is a plan view of a semiconductor device according to a second embodiment of the present invention. Figure 5 is a plan view of a semiconductor device according to a third embodiment of the present invention. Figure 6 is a graph obtained by measuring the optical output power of the semiconductor devices according to the first to third embodiments. Figure 7 is a graph obtained by measuring the operating voltage of the semiconductor device according to the first to third embodiments.

[0150] refer to Figure 3 , when the aluminum component increases, the current diffusion characteristics may deteriorate. Therefore, the current may diffuse only to the point adjacent to the first electrode 142, and the current density may decrease rapidly at the point away from the electrode 142. Therefore, the effective light emitting area P2 may be narrowed. The area from the point adjacent to the first electrode 142 with the highest current density to the boundary point with a current density of 40% or less may be defined as the effective light emitting area P2. For example, a point spaced 5μm to 40μm from the center of each groove 128 may be defined as a boundary point. However, the injected current level may vary depending on the aluminum component.

[0151] In particular, the low current density region P3 (i.e., the region between adjacent first electrodes 142) has a low current density and thus may hardly contribute to light emission. Therefore, according to an embodiment, a greater number of first electrodes 142 may be disposed in the low current density region C3 having a low current density, thereby increasing light output power.

[0152] For example, from Figure 4 It can be seen that Figure 4 Compared with the above, the area of ​​the low current density region P3 can be reduced. Figure 5 It can be seen that Figure 4 In comparison, the area of ​​the low current density region P3 can be further reduced.

[0153] Generally, since the GaN semiconductor layer has relatively good current diffusion characteristics, it is preferred to minimize the area of ​​the groove and the area of ​​the first electrode. This is because the area of ​​the active layer decreases as the area of ​​the groove and the area of ​​the first electrode increase. However, according to one embodiment, due to the high aluminum component, the current diffusion characteristics are relatively low. Therefore, it is preferred to increase the number of first electrodes while sacrificing the area of ​​the active layer.

[0154] The ratio of the diameter W1 of the groove to the size of the entire chip may be in the range of 1:0.038 to 1:0.060. When the ratio is less than 1:0.038, it is difficult to ensure a process margin for forming the first electrode 142 disposed in each groove 128. When the ratio is greater than 1:0.060, the removal volume of the light emitting layer 124 adjacent to the first electrode 142 increases, and thus the light emitting efficiency may be reduced. For example, the size of the chip may be 1,000 μm, but is not limited thereto.

[0155] Also, the ratio of the diameter W3 of the first electrode to the size of the entire chip may be in the range of 1:0.024 to 1:0.050. When the ratio is less than 1:0.024, the current injected into the first conductive semiconductor layer 122 may be insufficient. When the ratio is greater than 1:0.050, the number of first electrodes 142 disposed in the region of the first conductive semiconductor layer 122 may be insufficient, and thus may be disadvantageous in terms of current diffusion characteristics.

[0156] Reference Figure 6 , it can be seen from the second embodiment (where the number of grooves 128 is 31) that the light output power is increased to 114.7% of the light output power (100%) of the first embodiment, in which the number of grooves 128 is 14. Moreover, it can be seen that when the number of grooves is 44, the light output power is increased to 140.1%. That is, it can be seen that although the overall area of ​​the active layer is reduced, the area of ​​the active layer participating in light emission is increased.

[0157] Reference Figure 7 , it can be seen from the second embodiment (where the number of grooves 128 is 31) that the operating voltage is reduced to 87% of the operating voltage (100%) of the first embodiment, in which the number of grooves 128 is 14. Moreover, it can be seen that when the number of grooves is 44, the operating voltage is reduced to 78%. That is, it can be seen that the current diffusion characteristics are improved due to the increase in the total area of ​​the first electrode, thereby reducing the operating voltage.

[0158] Figure 8 is a plan view of a semiconductor device according to a fourth embodiment of the present invention. Fig. 9 is a plan view of a semiconductor device according to a fifth embodiment of the present invention. Fig.10 is a plan view of a semiconductor device according to a sixth embodiment of the present invention. Fig.11 is a plan view of a semiconductor device according to a seventh embodiment of the present invention. Fig.12 is a graph obtained by measuring the optical output power of the semiconductor devices according to the fourth to seventh embodiments. Fig.13 is a graph obtained by measuring the operating voltage of the semiconductor device according to the fourth to seventh embodiments.

[0159] like Figure 8 As shown, when the number of the grooves 128 is 48, the grooves 128 may be arranged in a zigzag shape instead of being arranged straightly in the horizontal or vertical direction. In this case, it can be seen that the area of ​​the low current density region P3 can be further reduced.

[0160] Reference Figures 9 to 11 It can be seen that when the number of the grooves 128 exceeds 62, the effective light emitting areas P2 overlap each other. Therefore, most of the active layer can participate in light emission.

[0161] The first area where the first electrodes 142 contact the first conductive semiconductor layer 122 may be 7.4% to 20% or 10% to 20% of the maximum horizontal cross-sectional area of ​​the light emitting structure 120. The first area may be the total area where the first electrodes 142 contact the first conductive semiconductor layer 122.

[0162] When the first area of ​​the plurality of first electrodes 142 is less than 7.4%, the current spreading characteristic is insufficient, so the optical output power is reduced. When the first area is greater than 20%, the areas of the active layer 126 and the second electrode 246 are excessively reduced, so the operating voltage is increased and the optical output power is reduced.

[0163] Moreover, the total area of ​​the plurality of grooves 128 may be within a range of 13% to 30% of the maximum horizontal cross-sectional area of ​​the light emitting structure 120. When the total area of ​​the grooves 128 is not within this range, it is difficult to maintain the total area of ​​the first electrode 142 within a range of 7.4% to 20%. Furthermore, the operating voltage increases and the light output power decreases.

[0164] The second region where the second electrode 246 contacts the second conductive semiconductor layer 126 may be in the range of 35% to 70% of the maximum horizontal sectional area of ​​the light emitting structure 120. The second region may be the total area where the second electrode 246 contacts the second conductive semiconductor layer 126.

[0165] When the second area is less than 35%, the area of ​​the second electrode is so small that the operating voltage may increase and the hole injection efficiency may decrease. When the second area exceeds 70%, the first area cannot be effectively widened, and thus the electron injection efficiency may decrease.

[0166] That is, the first area is inversely proportional to the second area. When the number of grooves increases to increase the number of the first electrode, the area of ​​the second electrode decreases. In order to improve the light output power, the diffusion characteristics of electrons and holes should be balanced. Therefore, it is important to determine the appropriate ratio between the first area and the second area.

[0167] Reference Fig.12It can be seen that when compared with the fourth embodiment in which the light output power is 100% and the number of grooves 128 is 48, when the number of grooves 128 increases, the light output power increases. Fig.13 , it can be seen that, when compared with the fourth embodiment in which the light output power is 100% and the number of the grooves 128 is 48, when the number of the grooves 128 increases, the operating voltage decreases.

[0168] As shown in Table 1 below, the area of ​​the light emitting structure, the area of ​​the p-ohmic electrode (second area), the area of ​​the groove, the area of ​​the n-ohmic electrode (first area), and the number of grooves of the first to seventh embodiments were measured.

[0169] The maximum horizontal area of ​​the light emitting structure may be an area obtained by summing the area of ​​the light emitting structure and the area of ​​the groove. That is, the maximum horizontal area of ​​the light emitting structure (the sum of the areas of the light emitting structure and the groove) may be 100%, and each area may be calculated based on the maximum horizontal area of ​​the light emitting structure.

[0170] The area of ​​the light emitting structure may be the maximum area of ​​the light emitting structure excluding the area of ​​the groove. That is, as the area of ​​the groove increases, the area of ​​the light emitting structure decreases.

[0171] The area of ​​a groove is the portion of the total area occupied by the groove.

[0172] The area of ​​the p-ohmic electrode may be a portion where the area of ​​the second electrode decreases as the number of grooves increases.

[0173] The area of ​​the n-ohmic electrode may be a portion where the area of ​​the first electrode decreases as the number of the grooves 128 increases.

[0174] Table 1

[0175]

[0176] Referring to the first to seventh embodiments, it can be seen that as the number of grooves 128 increases, the area of ​​the light emitting structure and the area of ​​the second electrode (p-ohmic electrode) decrease, and the total area of ​​the grooves 128 and the area of ​​the first electrode (n-ohmic electrode) gradually increase.

[0177] A ratio of a first area where the plurality of first electrodes 142 contact the first conductive semiconductor layer to a second area where the second electrode 246 contact the second conductive semiconductor layer (first area:second area) may be in the range of 1:3 to 1:7.

[0178] When the area ratio is greater than 1:10, the first area is relatively small so that the current diffusion characteristics may be deteriorated. For example, in the first embodiment, the first area is only about 1.8%, so the current injection efficiency may be reduced. Therefore, light is emitted only in the area adjacent to the first electrode.

[0179] In the first to seventh embodiments, the size of the chip, the size of the groove, and the size of the first electrode can be controlled in the same manner. For example, the groove 128 can have a diameter of 56 μm, and the first electrode can have a diameter of 42 μm. As the number of grooves and the number of first electrodes increase, the first area increases and the second area decreases.

[0180] Fig.14 is a plan view of a semiconductor device according to an eighth embodiment of the present invention. Fig.15 is a plan view of a semiconductor device according to a ninth embodiment of the present invention. Fig.16 is a plan view of a semiconductor device according to a tenth embodiment of the present invention. Fig.17 is a plan view of a semiconductor device according to an eleventh embodiment of the present invention. Fig.18 is a plan view of a semiconductor device according to a twelfth embodiment of the present invention. Fig.19 is a graph obtained by measuring the optical output powers of the semiconductor devices according to the ninth to twelfth embodiments. Fig. 20 is a graph obtained by measuring the operating voltages of the semiconductor devices according to the ninth to twelfth embodiments.

[0181] refer to Fig.16 , the diameter of the groove 128 is reduced to increase the number of the grooves 128 to 181. For example, the groove 128 may have a diameter W13 of 38 μm, and the first electrode may have a diameter W32 of 24 μm.

[0182] Moreover, reference Fig.18 , the diameter of the groove 128 is further reduced to increase the number of the grooves 128 to 236. For example, the groove 128 may have a diameter W13 of 32 μm, and the first electrode may have a diameter W33 of 20 μm.

[0183] Reference Fig.19 It can be seen that when the number of grooves 128 increases to 181 and 208, the optical output power is slightly higher than the optical output power (100%) of the ninth embodiment. However, it can be seen that when the number of grooves 128 increases to 236, the optical output power decreases.

[0184] Reference Fig. 20 It can be seen that when the number of grooves 128 increases to 181 and 236, the operating voltage is higher than that of the ninth embodiment.

[0185] As shown in Table 2 below, the area of ​​the light emitting structure, the area of ​​the p-ohmic electrode, the total area of ​​the grooves, the total area of ​​the n-ohmic electrode, and the number of the grooves of the eighth to twelfth embodiments were measured.

[0186] As defined in Table 1, the maximum horizontal area of ​​the light emitting structure may be an area obtained by adding the area of ​​the light emitting structure to the area of ​​the groove. That is, the maximum horizontal area of ​​the light emitting structure (the sum of the areas of the light emitting structure and the groove) may be 100%, and each area may be calculated based on the maximum horizontal area of ​​the light emitting structure.

[0187] Table 2

[0188]

[0189] Referring to Table 2, it can be seen from the tenth to twelfth embodiments that although the number of the grooves 128 increases, the total area of ​​the grooves 128 and the total area of ​​the first electrode decrease.

[0190] That is, it can be seen that even if a large number of grooves 128 and first electrodes 142 are provided by reducing their diameters, it is difficult to maintain the ratio of the first area to the second area below 1:3.

[0191] Summarizing Tables 1 and 2, when the ratio of the first area where the plurality of first electrodes contact the first conductive semiconductor layer to the second area where the second electrode contact the second conductive semiconductor layer (first area: second area) is in the range of 1:3 to 1:7 m, the number or area of ​​the grooves can be optimized, thereby facilitating production and also effectively improving light output power. The operating voltage can also be effectively reduced.

[0192] The ratio of the first area to the second area can be controlled in various ways. For example, when the number or area of ​​the grooves increases, the first area can increase and the second area can decrease.

[0193] However, the present invention is not limited thereto, and the ratio of the first area to the second area may be adjusted by controlling various factors.

[0194] For example, Figure 2 As shown, the area of ​​the first electrode can be controlled by controlling the width d5 ​​of the first insulating layer set at the top of the groove, and the area of ​​the second electrode can be controlled by controlling the spacing distance between the second electrode 246 and the first insulating layer 131 (extending to the lower part of the second conductive semiconductor layer 126).

[0195] In the ninth to eleventh embodiments, when the total area of ​​the grooves formed on the second conductive semiconductor layer is controlled within a range of 20% to 30% of the maximum horizontal cross-sectional area of ​​the light emitting structure, the light output power can be effectively increased and the operating voltage can be reduced.

[0196] A plurality of grooves may have an interval greater than 9.0 μm or 13.5 μm. As a result of measurement, the interval between the second electrodes (interval between the grooves) is 56 μm in the eighth embodiment, 19 μm in the ninth embodiment, 13.5 μm in the tenth embodiment, 9.0 μm in the eleventh embodiment, and 8.5 μm in the twelfth embodiment. For the tenth to twelfth embodiments, although the area of ​​the active layer is reduced, the interval between the second electrodes is narrowed. Therefore, the light output power is reduced, and the operating voltage is increased.

[0197] Fig.21 is a conceptual diagram of a light emitting structure according to an embodiment of the present invention. Fig. 22 By measuring Fig.21 Figure 3. The light-emitting structure obtained from the aluminum component.

[0198] The light emitting structure 120 according to the embodiment may output light of an ultraviolet wavelength. For example, the light emitting structure 120 may output light of a near ultraviolet wavelength (UV-A), a far ultraviolet wavelength (UV-B), or a deep ultraviolet wavelength (UV-C). The wavelength range may be determined by the aluminum component of the light emitting structure 120.

[0199] For example, near ultraviolet wavelength light (UV-A) may have a wavelength of 320nm to 420nm, far ultraviolet wavelength light (UV-B) may have a wavelength of 280nm to 320nm, and deep ultraviolet wavelength light (UV-C) may have a wavelength of 100nm to 280nm.

[0200] Reference Fig.21 The semiconductor device according to the embodiment includes a light emitting structure 120 including a first conductive semiconductor layer 124 , a second conductive semiconductor layer 127 , and an active layer 126 disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127 .

[0201] The first conductive semiconductor layer 124 may be made of a group III-V or group II-VI compound semiconductor and may be doped with a first dopant. The first conductive semiconductor layer 124 may be made of a semiconductor selected from a group having an empirical formula of In x1 Al y1 Ga 1-x1-y1 The first conductive semiconductor layer 124 may be made of a material selected from semiconductor materials having a value of N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1), for example, GaN, AlGaN, InGaN, InAlGaN, etc. Moreover, the first dopant may be an n-type dopant such as Si, Ge, Sn, Se, and Te. When the first dopant is an n-type dopant, the first conductive semiconductor layer 124 doped with the first dopant may be an n-type semiconductor layer.

[0202] The active layer 126 is disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127. The active layer 126 is a layer in which electrons (or holes) injected through the first conductive semiconductor layer 124 are combined with holes (or electrons) injected through the second conductive semiconductor layer 127. Due to the recombination between the electrons and the holes, the active layer 126 may be transformed into a lower energy level and generate light having an ultraviolet wavelength.

[0203] The active layer 126 may have, but is not limited to, any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure.

[0204] The second conductive semiconductor layer 127 may be formed on the active layer 126 and may be made of a group III-V or group II-VI compound semiconductor. Also, the second conductive semiconductor layer 127 may be doped with a second dopant. The second conductive semiconductor layer 127 may be made of a semiconductor having an empirical formula of In x5 Al y2 Ga 1-x5-y2 The second conductive semiconductor layer 127 may be made of a semiconductor material selected from the group consisting of AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, and Ba, the second conductive semiconductor layer 127 doped with the second dopant may be a p-type semiconductor layer.

[0205] The second conductive semiconductor layer 127 may include a 2-1 conductive semiconductor layer 127a having a high aluminum composition and a 2-2 conductive semiconductor layer 127b having a relatively low aluminum composition.

[0206] The second electrode 246 may make ohmic contact with the 2-2 conductive semiconductor layer 127b. The second electrode 246 may include a transparent electrode having relatively low ultraviolet light absorption. For example, the second electrode 246 may be formed of ITO, but is not limited thereto.

[0207] Current may be injected from the second conductive layer 150 into the second conductive semiconductor layer 127. Also, the second conductive layer 150 may reflect light emitted from the active layer 126.

[0208] According to one embodiment, the second electrode 246 may be in direct contact with a semiconductor layer (e.g., P-AlGaN) having a bandgap greater than the energy of the ultraviolet wavelength. Conventionally, the second electrode 246 is disposed on a GaN layer having a small bandgap for ohmic connection, so that most of the ultraviolet light is absorbed by the GaN layer. However, according to an embodiment, the second electrode 246 is in direct ohmic contact with the P-AlGaN, so that most of the light can pass through the second conductive semiconductor layer 127.

[0209] However, most of the second electrode absorbs ultraviolet light. Therefore, it is necessary to improve light extraction efficiency while maintaining ohmic contact of the second electrode.

[0210] Reference Fig. 22 , the electron blocking layer 129 may be disposed between the active layer 126 and the second conductive semiconductor layer 127. The electron blocking layer 129 may block the electrons provided from the first conductive semiconductor layer 124 from flowing out to the second conductive semiconductor layer 127, thereby increasing the possibility of electrons and holes in the active layer 126 being recombined with each other. The electron blocking layer 129 may have a higher energy band gap than the active layer 126 and / or the second conductive semiconductor layer 127.

[0211] The electron blocking layer 129 may be selected from a material having the empirical formula In x1 Al y1 Ga 1-x1-y1 The electron blocking layer 129 may be made of a material selected from semiconductor materials of N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1), such as AlGaN, InGaN, InAlGaN, etc., but not limited thereto. The electron blocking layer 129 may have a first layer 129b having a high aluminum component and a second layer 129a having a low aluminum component alternately disposed therein.

[0212] The first conductive semiconductor layer 124, the active layer 126 including the barrier layer 126b and the well layer 126a, the 2-1 conductive semiconductor layer 127a, and the 2-2 conductive semiconductor layer 127b may all contain aluminum. Therefore, the first conductive semiconductor layer 124, the barrier layer 126b, the well layer 126a, the 2-1 conductive semiconductor layer 127a, and the 2-2 conductive semiconductor layer 127b may be made of AlGaN. However, the present invention is not limited thereto.

[0213] The 2-1 conductive semiconductor layer 127a may have a thickness greater than 10 nm and less than 200 nm. When the thickness of the 2-1 conductive semiconductor layer 127a is less than 10 nm, its resistance increases in the horizontal direction, so the current injection efficiency may decrease. Also, when the thickness of the 2-1 conductive semiconductor layer 127a is greater than 200 nm, its resistance increases in the vertical direction, so the current injection efficiency may decrease.

[0214] The 2-1 conductive semiconductor layer 127a may have a higher aluminum composition than the well layer 126a. In order to generate ultraviolet light, the aluminum composition of the well layer 126a may be in the range of about 30% to about 50%. When the 2-1 conductive semiconductor layer 127a has a lower aluminum composition than the well layer 126a, the 2-1 conductive semiconductor layer 127a absorbs light, and thus light extraction efficiency may be reduced.

[0215] The aluminum composition of the 2-1 conductive semiconductor layer 127a may be greater than 40% and less than 80%. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is less than 40%, the 2-1 conductive semiconductor layer 127a absorbs light. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is greater than 80%, the current injection efficiency may be deteriorated. For example, when the aluminum composition of the well layer 126a is 30%, the aluminum composition of the 2-1 conductive semiconductor layer 127a may be 40%.

[0216] The 2-2 conductive semiconductor layer 127b may have a lower aluminum composition than a layer having the lowest aluminum composition among the plurality of well layers 126a. When the 2-2 conductive semiconductor layer 127b has a higher aluminum composition than the well layer 126a, resistance between the second electrode and the 2-2 conductive semiconductor layer 127b increases, and thus it may be difficult to sufficiently inject current.

[0217] The aluminum component of the 2-2 conductive semiconductor layer 127b may be greater than 1% and less than 50%. When the aluminum component is greater than 50%, the 2-2 conductive semiconductor layer 127b may not be able to make sufficient ohmic contact with the p-ohmic electrode. When the aluminum component is less than 1%, the aluminum component is almost a GaN composition, and thus the 2-2 conductive semiconductor layer 127b absorbs light.

[0218] The thickness of the 2-2 conductive semiconductor layer 127b may be greater than 1 nm and less than 30 nm. As described above, the 2-2 conductive semiconductor layer 127b has a sufficiently low aluminum component to form an ohmic contact, so that ultraviolet light can be absorbed. Therefore, in terms of light output power, it is advantageous to control the 2-2 conductive semiconductor layer 127b to be as thin as possible.

[0219] When the thickness of the 2-2 conductive semiconductor layer 127b is controlled to be 1 nm or less, the 2-2 conductive semiconductor layer 127b is so thin that the 2-2 conductive semiconductor layer 127b may not be provided in some portions, and further, the 2-1 conductive semiconductor layer 127a may be partially exposed from the light emitting structure 120. Therefore, it may be difficult for the 2-2 conductive semiconductor layer 127b to be formed as a single layer and also play its role. Moreover, when the thickness is greater than 30 nm, the amount of light absorbed is so large that the light output power efficiency may be reduced.

[0220] The 2-2 conductive semiconductor layer 127b may include a 2-3 conductive semiconductor layer 127c and a 2-4 conductive semiconductor layer 127d. The 2-3 conductive semiconductor layer 127c may be a surface layer in contact with the p-ohmic electrode, and the 2-4 conductive semiconductor layer 127d may be a layer for adjusting an aluminum composition.

[0221] The 2-4 conductive semiconductor layer 127d may be disposed between the 2-1 conductive semiconductor layer 127a having a relatively high aluminum content and the 2-3 conductive semiconductor layer 127c having a relatively low aluminum content. Therefore, degradation of crystallinity due to rapid changes in aluminum content may be prevented.

[0222] The aluminum component of the 2-3 conductive semiconductor layer 127c may be greater than 1% and less than 20%. Alternatively, the aluminum component may be greater than 1% and less than 10%.

[0223] When the aluminum composition is less than 1%, the 2-3 conductive semiconductor layer 127c may have too high light absorption rate. When the aluminum composition is greater than 20%, the contact resistance of the second electrode (p-ohmic electrode) increases, and thus the current injection efficiency may decrease.

[0224] However, the present invention is not limited thereto, and the aluminum composition of the 2-3 conductive semiconductor layer 127c may be adjusted in consideration of current injection characteristics and light absorption rate. Alternatively, the aluminum composition may be adjusted according to the light output power required by the product.

[0225] For example, when the current injection characteristic is more important than the light absorption rate, the aluminum composition can be adjusted to a range of 1% to 10%. When the light output power characteristic in the product is more important than the electrical characteristic, the aluminum composition of the 2-3 conductive semiconductor layer 127c can be adjusted to a range of 1% to 20%.

[0226] When the aluminum component of the 2-3 conductive semiconductor layer 127c is greater than 1% and less than 20%, the resistance between the 2-3 conductive semiconductor layer 127c and the second electrode is reduced, so the operating voltage is reduced. Therefore, the electrical characteristics can be improved. The thickness of the 2-3 conductive semiconductor layer 127c can be greater than 1nm and less than 10nm. Therefore, the light absorption problem can be alleviated.

[0227] The 2-2 conductive semiconductor layer 127b may have a smaller thickness than the 2-1 conductive semiconductor layer 127a. The thickness of the 2-1 conductive semiconductor layer 127a and the thickness of the 2-2 conductive semiconductor layer 127b may have a ratio ranging from 1.5:1 to 20:1. When the thickness ratio is less than 1.5:1, the 2-1 conductive semiconductor layer 127a is so thin that current injection efficiency may be reduced. Also, when the thickness ratio is greater than 20:1, the 2-2 conductive semiconductor layer 127b is so thin that ohmic reliability may be reduced.

[0228] The 2-1 conductive semiconductor layer 127a may have an aluminum composition that decreases away from the active layer 126. Also, the 2-2 conductive semiconductor layer 127b may have an aluminum composition that decreases away from the active layer 126. Thus, the aluminum composition of the 2-3 conductive semiconductor layer 127c may be in the range of 1% to 10%.

[0229] However, the present invention is not limited thereto, and the aluminum composition of the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b may include some portions that are not reduced, rather than being continuously reduced.

[0230] In this case, the 2-2 conductive semiconductor layer 127b may have a greater reduction in aluminum composition than the 2-1 conductive semiconductor layer 127a. That is, the 2-2 conductive semiconductor layer 127b may have a greater variation in aluminum composition in the thickness direction than the 2-1 conductive semiconductor layer 127a. Here, the thickness direction may refer to a direction from the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127 or a direction from the second conductive semiconductor layer 127 to the first conductive semiconductor layer 124.

[0231] The 2-1 conductive semiconductor layer 127a should have a greater thickness than the 2-2 conductive semiconductor layer 127b and have a higher aluminum composition than the well layer 126a. Therefore, the aluminum composition of the 2-1 conductive semiconductor layer 127a may be relatively gradually reduced.

[0232] However, the 2-2 conductive semiconductor layer 127b has a small thickness and a large variation in aluminum composition. Therefore, the 2-2 conductive semiconductor layer 127b may have a relatively high reduction in aluminum composition.

[0233] Fig.23a and 23b is a view showing a configuration in which light output power is enhanced according to a change in the number of grooves.

[0234] When the aluminum composition of the light emitting structure 120 increases, the current spreading characteristics in the light emitting structure 120 may be deteriorated. Also, the active layer 124 has a large amount of light (TM mode) emitted to the side compared to a GaN-based blue light emitting device. The TM mode may be performed by an ultraviolet semiconductor device.

[0235] The ultraviolet semiconductor device has a reduced current spreading characteristic compared to the blue GaN semiconductor device. Therefore, the ultraviolet semiconductor device needs to have a relatively large number of first electrodes 142 disposed therein compared to the blue GaN semiconductor device.

[0236] When the aluminum content increases, the current spreading characteristics may deteriorate. Fig.23a, the current spreads only to a point adjacent to the first electrode 142, and the current density may decrease rapidly at a point away from the electrode 142. Therefore, the effective light emitting area P2 may be narrowed.

[0237] The effective light emitting region P2 may be defined as a region from the center of the first electrode 142 having the highest current density to a boundary having a current density of 40% or less. For example, depending on the injected current and the level of the aluminum component, the effective light emitting region P2 may be adjusted to within 40 μm from the center of each groove 128.

[0238] The low current density region P3 may have low current density and thus may hardly contribute to light emission. Therefore, according to an embodiment, light output power may be increased by placing a larger number of first electrodes 142 in the low current density region P3 having low current density or by using a reflective structure.

[0239] Generally, since the GaN semiconductor layer has relatively good current diffusion characteristics, it is preferred to minimize the area of ​​the groove 128 and the area of ​​the first electrode 142. This is because the area of ​​the active layer 126 decreases as the area of ​​the groove 128 and the first electrode 142 increases. However, according to one embodiment, due to the high aluminum component, the current diffusion characteristics are relatively low. Therefore, it may be preferred to place the reflective structure in the low current density region P3 and reduce the low current density region P3 by increasing the number of first electrodes 142 while sacrificing the area of ​​the active layer 126.

[0240] refer to Figure 23b When the number of the grooves 128 is 48, the grooves 128 may be arranged in a zigzag shape rather than being arranged straightly in the horizontal or vertical direction. In this case, it can be seen that the area of ​​the low current density region P3 can be further reduced, so most of the active layer 126 can participate in light emission.

[0241] When the number of grooves 128 is in the range of 70 to 110, current can be effectively diffused, so the operating voltage can also be reduced and the light output power can be increased. For a semiconductor device that emits UV-C light, when the number of grooves 128 is less than 70, electrical characteristics and optical characteristics may be degraded. When the number of grooves 128 is greater than 110, electrical characteristics can be improved, but optical characteristics may be degraded due to the reduction in volume of the light-emitting layer. In this case, each groove 128 may have a diameter in the range of 20 μm to 70 μm.

[0242] The above configuration may be applied to the area of ​​the groove, the area of ​​the first electrode, the area of ​​the second electrode, and the ratio therebetween.

[0243] Fig.24 is a conceptual diagram of a semiconductor device according to a thirteenth embodiment of the present invention.

[0244] Already referenced Fig.21 or Fig. 22 The configuration of the light emitting structure 120 described can be applied to Fig.24 A light emitting structure 120 is provided.

[0245] A plurality of grooves 128 may extend from the first surface of the second conductive semiconductor layer 127 to a portion of the first conductive semiconductor layer 124 through the active layer 126. A first insulating layer 131 may be disposed inside each groove 128 to electrically insulate the first conductive layer 165 from the second conductive semiconductor layer 127 and the active layer 126.

[0246] The first electrode 142 may be disposed on the top of each groove 128 and electrically connected to the first conductive semiconductor layer 124. The second electrode 246 may be formed under the second conductive semiconductor layer 127.

[0247] As described above, the first surface 127G of the second conductive semiconductor layer 127 contacting the second electrode 246 may have an aluminum composition ranging from 1% to 10%, and thus injection of current may be facilitated.

[0248] Each of the first electrode 142 and the second electrode 246 may be an ohmic electrode. Each of the first electrode 142 and the second electrode 246 may be made of at least one of 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 tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), aluminum nitride (IZON), Al-Ga ZnO (AGZO), In-Ga ZnO (IGZO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au, Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, and Hf, but is not limited thereto.

[0249] The second electrode pad 166 may be disposed in an edge region of the semiconductor device. The second electrode pad 166 may have a concave central portion and thus have a top surface including a concave portion and a convex portion. A wire (not shown) may be bonded to the concave portion of the top surface. Therefore, due to the increase in the bonding area, the second electrode pad 166 and the wire may be firmly bonded to each other.

[0250] The second electrode pad 166 may reflect light. Therefore, when the second electrode pad 166 is closer to the light emitting structure 120, light extraction efficiency may be improved.

[0251] The convex portion of the second electrode pad 166 may be higher than the active layer 126. Therefore, the second electrode pad 166 may improve light extraction efficiency and control an orientation angle by reflecting light emitted from the active layer 126 in a horizontal direction upward to the device.

[0252] The first insulating layer 131 is partially opened under the second electrode pad 166 so that the second conductive layer 150 and the second electrode 246 may be electrically connected to each other.

[0253] The passivation layer 180 may be formed on the top and side of the light emitting structure 120. The passivation layer 180 may contact the first insulating layer 131 in a region adjacent to the second electrode 246 or in a lower portion of the second electrode 246.

[0254] The opening of the first insulating layer 131 where the second electrode pad 166 contacts the second conductive layer 150 may have a width d22 ranging from, for example, 40 μm to 90 μm. When the width d22 is less than 40 μm, the operating voltage may increase. When the width d22 is greater than 90 μm, it may be difficult to ensure a process margin for preventing the second conductive layer 150 from being exposed. When the second conductive layer 150 is exposed to the outside of the second electrode 246, the reliability of the device may be reduced. Therefore, the width d22 may preferably be in the range of 60% to 95% of the entire width of the second electrode pad 166.

[0255] The first insulating layer 131 may electrically insulate the first electrode 142 from the active layer 126 and the second conductive semiconductor layer 127. In addition, the first insulating layer 131 may electrically insulate the second conductive layer 150 from the first conductive layer 165.

[0256] 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 N y , Al2O3, TiO2, and AlN. The first insulating layer 131 may be formed as a single layer or multiple layers. For example, 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.

[0257] When the first insulating layer 131 performs a reflective function, the first insulating layer 131 can reflect light horizontally emitted from the active layer 126 upward, thereby improving light extraction efficiency. As the number of grooves 128 increases, the ultraviolet semiconductor device can have more effective light extraction efficiency than a semiconductor device emitting blue light.

[0258] The second conductive layer 150 may cover the second electrode 246. Therefore, the second electrode pad 166, the second conductive layer 150, and the second electrode 246 may form one electrical path.

[0259] The second conductive layer 150 may cover the second electrode 246 and may contact the side surface and the top surface of the first insulating layer 131. The second conductive layer 150 may be made of a material having a high adhesive strength with the first insulating layer 131, and may also be made of at least one material selected from the group consisting of Cr, Al, Ti, Ni, and Au, or an alloy thereof. The second conductive layer 150 may be formed as a single layer or a multilayer.

[0260] When the second conductive layer 150 contacts the side and top surfaces of the first insulating layer 131, thermal and electrical reliability of the second electrode 246 may be improved. Also, the second conductive layer 150 may have a reflective function for reflecting light emitted from a gap between the first insulating layer 131 and the second electrode 246 upward.

[0261] The second insulating layer 132 may electrically insulate the second conductive layer 150 from the first conductive layer 165. The first conductive layer 165 may be electrically connected to the first electrode 142 through the second insulating layer 132.

[0262] The first conductive layer 165 and the junction layer 160 may be provided according to the shape of the bottom surface of the light emitting structure 120 and the shape of the groove 128. The first conductive layer 165 may be made of a material having a high reflectivity. For example, the first conductive layer 165 may include aluminum. When the first conductive layer 165 includes aluminum, the first conductive layer 165 may be used to reflect light emitted from the active layer 126 upward, thereby improving light extraction efficiency.

[0263] The junction layer 160 may include a conductive material. For example, the junction 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.

[0264] The substrate 170 may be made of a conductive material. For example, the substrate 170 may include a metal or a semiconductor material. The substrate 170 may be made of a metal having high electrical conductivity and / or thermal conductivity. In this case, the heat generated during operation of the semiconductor device may be quickly released to the outside.

[0265] The substrate 170 may include a material selected from the group consisting of silicon, molybdenum, tungsten, copper, and aluminum, or an alloy thereof.

[0266] A square wave pattern may be formed on the top of the light emitting structure 120. The square wave pattern may improve the extraction efficiency of light emitted from the light emitting structure 120. The square wave pattern may have different average heights depending on the wavelength of ultraviolet light. For UV-C, the average height ranges from 300 nm to 800 nm. When the average height is in the range of 500 nm to 600 nm, the light extraction efficiency may be improved.

[0267] Fig.25 yes Fig.24 Floor plan, Fig.26 is along Fig.25 A cross-sectional view taken along line AA.

[0268] Reference Fig.25 and Fig.26 , when viewed from above, the first surface 127G of the second conductive semiconductor layer 127 may include a plurality of first regions 127G-1 surrounding the plurality of grooves 128 and second regions 127G-2 disposed between the plurality of first regions 127G-1. Here, each of the first regions 127G-1 may be an annular region between the second region 127G-2 and the outer peripheral surface of each groove 128.

[0269] Each groove 128 may have a diameter ranging from 20 μm to 70 μm. When the diameter is less than 20 μm, it is difficult to ensure a process margin for forming the first electrode 142 disposed therein. When the diameter is greater than 70 μm, the area of ​​the active layer 126 is so small that the light emitting efficiency may be deteriorated. Here, the diameter of the groove 128 may be the maximum diameter formed on the second conductive semiconductor layer 127.

[0270] The diameter of each first region 127G-1 is 1.0 to 1.5 times the diameter of the groove 128. When the diameter exceeds 1.5 times, the contact area of ​​the second electrode 246 is so small that the current diffusion efficiency may be reduced. The first region 127G-1 may indicate a distance S11 between the maximum outer diameter of each groove 128 and the second electrode 246.

[0271] The second region 127G-2 may be the entire region except for the plurality of first regions 127G-1. The second electrode 246 may be entirely disposed on the second region 127G-2.

[0272] The first area of ​​the plurality of first electrodes 142 contacting the first conductive semiconductor layer 124 may be in the range of 7.4% to 20% or 10% to 20% of the maximum horizontal cross-sectional area of ​​the light emitting structure. The first area may be the sum of the areas of the first electrodes 142 contacting the first conductive semiconductor layer 124.

[0273] When the first area of ​​the plurality of first electrodes 142 is less than 7.4%, the current spreading characteristic is insufficient, so the optical output power is reduced. When the first area is greater than 20%, the areas of the active layer 126 and the second electrode 246 are excessively reduced, so the operating voltage is increased and the optical output power is reduced.

[0274] Moreover, the total area of ​​the plurality of grooves 128 may be in the range of 10% to 30% or 13% to 30% of the maximum horizontal cross-sectional area of ​​the light emitting structure 120. When the total area of ​​the grooves 128 is not in this range, it is difficult to maintain the total area of ​​the first electrode 142 in the range of 7.4% to 20%. Moreover, the operating voltage increases and the light output power decreases.

[0275] The area of ​​the second conductive semiconductor layer 127 may be equal to the maximum horizontal area of ​​the light emitting structure 120 minus the total area of ​​the groove 128. For example, the area of ​​the second conductive semiconductor layer 127 may be in the range of 70% to 90% of the maximum horizontal area of ​​the light emitting structure 120.

[0276] The second area ( Fig.25 The second area may be a total area where the second electrode 246 contacts the second conductive semiconductor layer 127, and the second area may be a range of 50% to 70% of the maximum horizontal cross-sectional area of ​​the light emitting structure 120.

[0277] When the second area is less than 50%, the area of ​​the second electrode 246 is so small that the operating voltage may increase and the hole injection efficiency may decrease. When the second area exceeds 70%, the first area cannot be effectively widened, and thus the electron injection efficiency may decrease. The area ( Fig.25 The first region in the figure) can be in the range of 1% to 20%.

[0278] The first area is inversely proportional to the second area. That is, when the number of grooves 128 is increased to increase the number of first electrodes 142, the area of ​​the second electrode 246 is reduced. Therefore, in order to improve electrical and optical properties, the diffusion characteristics of electrons and holes should be balanced. Therefore, it is important to determine an appropriate ratio between the first area and the second area.

[0279] A ratio of a first area where the plurality of first electrodes 142 contact the first conductive semiconductor layer 124 to a second area where the second electrode 246 contact the second conductive semiconductor layer 127 (first area: second area) ranges from 1:3 to 1:7.

[0280] When the area ratio is greater than 1:7, the first area is relatively small so that the current spreading characteristic may be degraded. Also, when the area ratio is less than 1:3, the second area is relatively small so that the current spreading characteristic may be degraded.

[0281] The ratio of the entire area of ​​the plurality of first regions 127G-1 to the area of ​​the second region 127G-2 may be in the range of 1:2.5 to 1:70 or 1:30 to 1:70. When the area ratio is less than 1:2.5, the area of ​​the first region 127G-1 is too large to ensure a sufficient ohmic area of ​​the second electrode 246. When the area ratio is greater than 1:70, the area of ​​the first region 127G-1 is so small that it is difficult to ensure a process margin.

[0282] The second electrode 246 may include a metal or metal oxide having low resistance. However, the second electrode 246 reflects or transmits visible light, but absorbs ultraviolet light. Therefore, it is necessary to reflect the light emitted from the active layer 126 to the second conductive semiconductor layer 127 by reducing the area of ​​the second electrode 246. For example, by reducing the second region 127G-2 where the second electrode 246 is provided and widening the first region 127G-1, the reflection region can be ensured, or the reflection structure can be selectively placed by dividing the second region 127G-2 into a plurality of regions.

[0283] The second conductive layer 150 is disposed on the first region 127G-1 and the second region 127G-2, so light incident on the first region 127G-1 may be reflected by the second conductive layer 150. In this case, it is important to ensure a maximum reflection area while ensuring a contact area of ​​the second electrode 246 required for diffusing current.

[0284] The area of ​​the second region 127G-2 may be in the range of 35% to 60% of the maximum area of ​​the light emitting structure 120. When the area of ​​the second region 127G-2 is less than 35%, the contact area of ​​the second electrode 246 is so small that the current diffusion efficiency may be reduced. Also, when the area of ​​the second region 127G-2 exceeds 60%, the area of ​​the first region 127G-1 is so small that the light extraction efficiency may be reduced.

[0285] The area of ​​the first region 127G-1 excluding the area of ​​the groove 128 may be in the range of 10% to 55% of the maximum area of ​​the light emitting structure 120. When the area of ​​the first region 127G-1 is less than 10%, it is difficult to have sufficient reflection efficiency. When the area of ​​the first region 127G-1 is greater than 55%, the area of ​​the second region 127G-2 is so small that the current spreading efficiency may be reduced.

[0286] Therefore, the ratio of the area of ​​the first region 127G-1 to the area of ​​the second region 127G-2 may be in the range of 1:0.7 to 1:6. When this relationship is satisfied, sufficient current diffusion efficiency is ensured, so that the light output power can be improved. Moreover, sufficient reflection area is ensured, so that the light extraction effect can be improved.

[0287] Reference Fig.26 , the first surface 127G of the second conductive semiconductor layer 127 may include a 1-1 surface S10 disposed between two adjacent grooves 128. The 1-1 surface S10 may include a second portion S2 where the second electrode 246 is not disposed and a first portion S1 where the electrode is disposed. The 1-1 surface S10 may have a width in the range of 17 μm to 45 μm.

[0288] When the width of the 1-1 surface S10 is less than 17 μm, the spacing distance between the grooves 128 is too small so that the arrangement area of ​​the second electrode 246 may be reduced, and thus the electrical characteristics may be degraded. When the width is greater than 45 μm, the spacing distance between the grooves 128 is too large so that the arrangement area of ​​the first electrode 142 may be reduced, and thus the electrical characteristics may be degraded.

[0289] The second portion S2 may be a unit portion forming the first region 127G-1. Moreover, the first portion S1 may be a unit portion forming the second region 127G-2. The first portion S1 may have a greater width than the second portion S2 in the first direction. The width of the second portion S2 in the first direction (the distance from the groove to the second electrode) may be in the range of 1 μm to 15 μm.

[0290] When the width of the second portion S2 is less than 1 μm, the first insulating layer 131a may be difficult to be disposed on the second conductive semiconductor layer 127 due to a process margin for current diffusion. Therefore, electrical characteristics may be degraded. When the width is greater than 15 μm, the distance between the second electrode 246 and the first electrode 142 is so large that electrical characteristics may be degraded. Therefore, considering the process margin and electrical characteristics, the width of the second portion S2 in the first direction may be within the above range.

[0291] The first insulating layer 131 may include an extension portion 131a extending to the first surface 127G, and the second electrode 246 may have a spacing area S13 of 0 μm to 4 μm from the extension portion 131a of the first insulating layer 131. When the spacing area S13 is greater than 4 μm, the second electrode 246 has a too small area so that the operating voltage may increase.

[0292] The second conductive layer 150 may completely surround the second electrode 246 and may be in contact with the side surface and the bottom surface of the first insulating layer 131. When the second conductive layer 150 is in contact with the side surface and on the top surface of the first insulating layer 131, the thermal and electrical reliability of the second electrode 246 may be improved. Also, it may have a function of reflecting incident ultraviolet light upward.

[0293] The second conductive layer 150 may have a region forming a Schottky junction with the second conductive semiconductor layer 127 in the spacer region S13. Therefore, diffusion of current may be facilitated.

[0294] The first surface 127G may have an average roughness maintained at or below 7nm. When the average roughness is greater than 7nm, the boundary surface between the second electrode 246 and the second conductive layer 150 is so rough that the reflectivity may be reduced. The average roughness may be a value obtained by calculating the height difference of the square wave pattern formed on the first surface 127G. The average roughness may be a root mean square (RMS) value measured by using an atomic force microscope (AFM).

[0295] Fig. 27 is a diagram showing the configuration of the second conductive layer. Fig.28 yes Fig. 27 The first modification example. Fig.29 yes Fig. 27 The second modification example.

[0296] Reference Fig. 27 , the second electrode 246 may have a thickness d5 ranging from 1 nm to 15 nm or 1 nm to 5 nm. When the thickness d5 of the second electrode 246 is less than 15 nm, the amount of absorbed light may decrease.

[0297] The second conductive layer 150 may include a reflective layer 151 including aluminum and a first intermediate layer 152 disposed between the second electrode 246 and the reflective layer 151. When the second electrode 246 is formed of ITO, oxygen may penetrate into the reflective layer 151 to form Al2O3. In this case, the reflection efficiency of the reflective layer 151 is reduced. In one embodiment, the first intermediate layer 152 may be disposed between the reflective layer 151 and the second electrode 246 to improve the adhesive strength therebetween and also prevent the penetration of oxygen.

[0298] The first intermediate layer 152 may include at least one of chromium (Cr), titanium (Ti) and nickel (Ni). The first intermediate layer 152 may have a thickness d6 ranging from 0.7 nm to 7 nm. The first intermediate layer 152 may also include aluminum. In this case, the bonding strength between the first intermediate layer 152 and aluminum can be improved. Moreover, the first intermediate layer 152 contacts the first surface 127G in the interval region, so that the current diffusion characteristics can be improved by the Schottky junction.

[0299] The thickness ratio (d5:d7) of the second electrode 246 and the reflective layer 151 may be in the range of 1:2 to 1:120. The reflective layer 151 may have a thickness d7 ranging from 30 nm to 120 nm. When the thickness of the reflective layer 151 is less than 30 nm, the reflectivity in the ultraviolet band is reduced. Even when the thickness is greater than 120 nm, the reflection efficiency is hardly increased.

[0300] Reference Fig.28 , the second intermediate layer 153 may be disposed under the reflective layer 151. The second intermediate layer 153 may prevent aluminum from migrating to an adjacent layer. The second intermediate layer 153 may include at least one of Ni, Ti, No, Pt, and W, and may have a thickness ranging from 50 nm to 200 nm.

[0301] Reference Fig.29 , the third intermediate layer 154 may be disposed under the second intermediate layer 153. The third intermediate layer 154 is a layer for bonding to another layer, and may contain Au, Ni, or the like.

[0302] Fig.30 is a conceptual diagram of a semiconductor device according to a fourteenth embodiment of the present invention. Fig.31 yes Fig.30 Floor plan. Fig.32 yes Fig.31 Enlarged view of part B-1. Fig.33 yes Fig.31 An enlarged view of part B-2.

[0303] Reference Fig.30 , refer to Figures 1 to 3 The light emitting structure 120 described and the reference Figure 4 The configuration of each layer described may be applied as it is to the semiconductor device according to the embodiment.According to the embodiment, a plurality of second electrodes 246 may be disposed on the first surface 127G of the second conductive semiconductor layer 127 disposed between the two grooves 128 .

[0304] Reference Figure 31 to Figure 33 The first surface 127G may include a first region 127G-1 surrounding the groove 128, a second region 127G-2 surrounding the first region 127G-1, and a third region 127G-3 disposed between the second regions 127G-2.

[0305] Here, the first region 127G-1 may be a region between the second electrode 246 and the groove 128. For example, the first region 127G-1 may have a ring-shaped region. The area of ​​the first region 127G-1 may be in the range of 1% to 20% of the maximum horizontal area of ​​the light emitting structure 120.

[0306] The second region 127G-2 may have the entire region except the groove 128 and the first region 127G-1. For example, the second regions 127G-2 may each have an inner circular shape and an outer polygonal shape. For example, the second regions 127G-2 may each have an outer octagonal shape, but are not limited thereto. The second region 127G-2 may be separated by a third region 127G-3. The third region 127G-3 may be disposed between a plurality of second regions 127G-2. The third region 127G-3 may be a region having a current density of 40% or less relative to the first electrode 142 having a current density of 100%. Therefore, the third regions 127G-3 may each have a low probability of participating in light emission. According to an embodiment, the third region 127G-3 having a low contribution to light emission may be configured as a reflective region to improve light extraction efficiency.

[0307] The first surface 127G may further include a fourth region 127G-4 disposed between a boundary region of the first surface 127G and the third region 127G-3.

[0308] The second electrode 246 may include a 2-1 electrode 246 a disposed in the second region 127G- 2 and a 2-2 electrode 246 b disposed in the fourth region 127G- 4 .

[0309] The second electrode 246 may include a metal or a metal oxide having low resistance. However, the second electrode 246 reflects or transmits visible light but absorbs ultraviolet light.

[0310] Therefore, it is necessary to reflect the light emitted from the active layer 126 to the second conductive semiconductor layer 127 by reducing the area of ​​the second electrode 246, as long as the electrical characteristics are not significantly deteriorated. In this case, the reflection area can be ensured by narrowing the second area 127G-2 where the second electrode 246 is provided and widening the third area 127G-3. Since the second conductive layer 150 is completely provided on the first surface 127G, the light incident on the third area 127G-3 can be reflected by the second conductive layer 150.

[0311] That is, according to this embodiment, the third region 127G- 3 having a low contribution to light emission can be utilized as a reflective region.

[0312] The first contact area ( Fig.31 The sum of the second and fourth regions (the sum of the second and fourth regions) may be in the range of 35% to 60% of the maximum area of ​​the light emitting structure 120. When the first contact area is less than 35%, the current spreading efficiency may be reduced. Also, when the first contact area exceeds 60%, the area of ​​the third region 127G-3 is so small that the light extraction efficiency may be reduced.

[0313] The second contact area ( Fig.31 The sum of the first and third regions (the sum of the first and third regions) may be in the range of 10% to 55% of the maximum area of ​​the light emitting structure 120. When the second contact area is less than 10%, it is difficult to have sufficient reflection efficiency. When the second contact area is greater than 55%, the area of ​​the second region 127G-2 is so small that the current spreading efficiency may be reduced.

[0314] The ratio of the second contact area to the first contact area may be in the range of 1:0.7 to 1:6. When this relationship is satisfied, sufficient current spreading efficiency is ensured, so that light output power can be improved. Also, sufficient reflection area is ensured, so that light extraction effect can be improved.

[0315] Reference Fig.33 , the boundary of the third region 127G-3 and the first surface 127G may be separated by a spacing distance ranging from 1.0 μm to 10 μm. When the spacing distance d1 is less than 1.0 μm, the margin is so small that the second conductive layer 150 may not be properly formed, and thus the reliability may be reduced. Moreover, when the spacing distance d1 is greater than 10 μm, the area of ​​the second electrode 246 is so small that the electrical characteristics of the semiconductor device may be degraded.

[0316] Fig.34 is along Fig.32 A cross-sectional view of BB.

[0317] Reference Fig.34 The first surface 127G of the second conductive semiconductor layer 151 may include a 1-1 surface S10 disposed between two grooves 128 most adjacent to each other in the first direction (X direction). Here, the first direction may be a direction perpendicular to the thickness direction of the light emitting structure 120.

[0318] The 1-1 surface S10 may include a first portion S11 in which two second electrodes 246 are spaced apart from each other in the first direction and a second portion S12 disposed between the second electrodes 246. The second conductive layer 150 may be disposed in the first portion S11 and the second portion S12. The entire width of the 1-1 surface S10 may be in the range of 17 μm to 45 μm.

[0319] The entire width of the first portion S11 in the first direction may be in the range of 12 μm to 24 μm. The first portion S11 may include two separation regions on both sides of the second portion S12. The separation regions may have a width ranging from 6 μm to 12 μm.

[0320] When the entire width of the first portion S11 is less than 12 μm, the area of ​​the second electrode 246 is so small that current spreading efficiency may be reduced. When the entire width is greater than 24 μm, the second portion S12 is so small that reflection efficiency may be reduced.

[0321] The width of the second portion S12 in the first direction may be in the range of 5 μm to 16 μm. When the width of the second portion S12 in the first direction is less than 5 μm, it is difficult to ensure a sufficient reflection area. When the width is greater than 16 μm, the second electrode 246 becomes narrow.

[0322] The second portion S12 may be disposed in a region having a current density of 40% or less relative to the first electrode 142 having a current density of 300%. The first distance W2+S13+S11 between the second portion S12 and the center of the groove 128 may be at least 17 μm. The radius of the bottom surface of the groove 128 may be in the range of 10 μm to 35 μm, the width of the third portion S13 may be in the range of 1 μm to 5 μm, and the width of the first portion S11 may be in the range of 6 μm to 12 μm. Therefore, the maximum spacing distance may be greater than or equal to 52 μm.

[0323] The second portion S12 may be disposed in a region having a current density of 40% or less in a region at least 17 μm away from the center of the groove 128. For example, the second portion S12 may be disposed in a region 40 μm or more away from the center of the groove 128.

[0324] When there are a plurality of grooves 128 in the semiconductor device, the second portions S12 disposed 40 μm or more away from the grooves 128 may overlap with each other. Therefore, the overlapping area of ​​the second portions S12 may be adjusted according to the distance between the grooves 128 .

[0325] In this case, the second portion S12 may include a point corresponding to 1 / 2 of the width of the 1-1 surface S10 in the first direction. The point corresponding to 1 / 2 of the width of the 1-1 surface S10 in the first direction is a region between two adjacent grooves 128 and may have a low current density. However, the present invention is not limited thereto. When the plurality of grooves have different diameters, the second portion S12 may not necessarily include a point corresponding to 1 / 2 of the width in the first direction.

[0326] The third portion S13 may be a region between the second electrode 246 and the groove 128. A width of the third portion S13 in the first direction may be in the range of 1 μm to 5 μm.

[0327] The ratio of the width of the second portion S12 to the entire width of the first portion S11 may be in the range of 1:0.7 to 1:5. When the width ratio range is satisfied, the ratio of the second contact area to the first contact area may be maintained in the range of 1:0.7 to 1:6. Therefore, the current spreading efficiency and the light extraction effect may be improved.

[0328] Fig.35 yes Fig.34 The first modification example.

[0329] Reference Fig.35 , the second conductive layer 150 may include a reflective groove 150-1 in the second portion S12. Light incident on the second portion S12 may be reflected along a propagation path changed by the reflective groove 150-1. According to this configuration, light may be reflected in various directions, thereby improving uniformity.

[0330] The inclined surface may have an angle θ5 greater than 90 degrees and less than 150 degrees. When the angle of the inclined surface is less than 90 degrees or greater than 150 degrees, it may be difficult to variously change the reflection angle of incident light. The angle of the inclined surface may be defined as an angle formed between the bottom surface and the inclined surface.

[0331] The depth of the reflective groove 150 - 1 may be the same as the thickness of the first insulating layer 131 . The thickness of the first insulating layer 131 may be equal to 110% to 130% of the thickness of the second electrode 246 .

[0332] The light-transmitting layer 133 may be disposed in the reflective groove 150-1. The shape of the light-transmitting layer 133 may correspond to the shape of the reflective groove 150-1. Therefore, the light-transmitting layer 133 may have the same thickness as the reflective groove 150-1. For example, the reflective groove 150-1 may be formed by forming the second conductive layer 150 on the light-transmitting layer 133.

[0333] The material of the light-transmitting layer 133 may include various materials that can transmit light of ultraviolet wavelengths. For example, the light-transmitting layer 133 may include an insulating layer material. The light-transmitting layer 133 may include SiO2, Si x O y 、Si3N4、Si x N y 、SiO x N y , Al2O3, TiO2 and AlN, but not limited thereto.

[0334] Fig.36a yes Fig.34 The second modification example, Fig.36b It is a plan view of the second modification example.

[0335] Reference Fig.36a, the sub groove 127 and the sub reflective layer 135 disposed in the sub groove 127 may be disposed in the second portion S12.

[0336] The sub-reflective layer 135 may be disposed in the sub-groove 127. Specifically, the sub-reflective layer 135 may be disposed on the first insulating layer 131 in the sub-groove 127.

[0337] As the sub-reflection layer 135, a material having a high reflectivity in the ultraviolet band may be selected. The sub-reflection layer 135 may include a conductive material. For example, the sub-reflection layer 135 may include aluminum. When the sub-reflection layer 135 has a thickness ranging from about 30 nm to about 120 nm, the sub-reflection layer 135 may reflect 80% or more of the light of the ultraviolet wavelength. Therefore, it is possible to prevent the light emitted from the active layer 126 from being absorbed by the semiconductor layer.

[0338] The light L1 obliquely emitted by the sub-reflection layer 135 may be reflected upward. Therefore, light absorption in the light emitting structure 120 may be reduced and light extraction efficiency may be improved. Furthermore, the orientation angle of the semiconductor device may also be adjusted.

[0339] The sub-reflective layer 135 may cover a portion of the second electrode 246. According to such a configuration, light flowing into the space between the first insulating layer 131 and the second electrode 246 may be reflected upward. However, the sub-reflective layer 135 made of aluminum has relatively poor step coverage, so full coverage of the second electrode 246 may not be preferred.

[0340] The thickness of the second electrode 246 may be less than or equal to 80% of the thickness of the first insulating layer 131. Therefore, problems such as cracks or separation of the sub-reflective layer 135 or the second conductive layer 150 due to a reduction in step coverage that may occur when the sub-reflective layer 135 and the second conductive layer 150 are provided may be solved.

[0341] The sub-reflective layer 135 may have the same width as the sub-groove 127. The width of the first groove 128 and the width of the sub-groove 127 may indicate a maximum width formed on the first surface 127G of the semiconductor structure 120.

[0342] The sub-reflective layer 135 may include an extension portion 135a extending toward the second electrode 246 in the sub-groove 127. The extension portion 135a may electrically connect the second electrode 246 spaced apart by the sub-groove 127.

[0343] The sub-reflective layer 135 may be disposed at a spacing distance between the second electrode 246 and the first insulating layer 131, and a region where a Schottky junction is formed between the sub-reflective layer 135 and the second conductive semiconductor layer 127 may be within the spacing distance. By forming a Schottky junction, diffusion of current may be facilitated.

[0344] An angle θ4 formed between the inclined portion of the sub-reflective layer 135 and the first surface of the second conductive semiconductor layer 127 may be in the range of 90 to 145 degrees. When the inclined angle θ4 is less than 90 degrees, it is difficult to etch the second conductive semiconductor layer 127. When the inclined angle θ4 is greater than 145 degrees, the etching area of ​​the active layer is so large that the light emitting efficiency may be reduced.

[0345] The second conductive layer 150 may cover the sub-reflective layer 135 and the second electrode 246. Therefore, the second electrode pad 166, the second conductive layer 150, the sub-reflective layer 135 and the second electrode 246 may form an electrical path. As the configuration of the second conductive layer 150, all of the above configurations may be applied.

[0346] Reference Fig.36b , the sub-reflective layer 135 may be disposed between the plurality of grooves 128 to define a plurality of light emitting regions. The area of ​​the light emitting region may be adjusted according to the injected current and the level of the aluminum component.

[0347] Fig.37 yes Fig.34 The third modification example.

[0348] The second conductive layer 150 may include a reflective layer 151 including aluminum and a first intermediate layer 152 disposed between the second electrode 246 and the reflective layer 151. When the second electrode 246 is formed of ITO, oxygen may penetrate into the reflective layer 151 to form Al2O3. In this case, the reflection efficiency of the reflective layer 151 is reduced. In one embodiment, the first intermediate layer 152 may be disposed between the reflective layer 151 and the second electrode 246, thereby improving the adhesive strength therebetween and also preventing the penetration of oxygen.

[0349] The first intermediate layer 152 may include at least one of chromium (Cr), titanium (Ti), and nickel (Ni). The first intermediate layer 152 may have a thickness ranging from 0.7 nm to 7 nm. The first intermediate layer 152 may also include aluminum. In this case, the bonding strength between the first intermediate layer 152 and aluminum may be improved.

[0350] The first intermediate layer 152 may contact the first surface 127G of the second conductive semiconductor layer 127 in the second portion S12 and the third portion S13. Therefore, current spreading efficiency may be improved by means of the Schottky junction.

[0351] The thickness ratio of the second electrode 246 to the reflective layer 151 may be in the range of 1:2 to 1:120. The reflective layer 151 may have a thickness ranging from 30 nm to 120 nm. When the thickness of the reflective layer 151 is less than 30 nm, the reflectivity in the ultraviolet band decreases. Even when the thickness is greater than 120 nm, the reflection efficiency is hardly increased.

[0352] Fig.38 is a conceptual diagram of a semiconductor device according to a fifteenth embodiment of the present invention. Fig.39 yes Fig.38 Floor plan.

[0353] Reference Fig.38 , refer to Figures 1 to 3 The light emitting structure 120 described and the reference Figure 4 The described configuration of each layer can be applied to the semiconductor device according to the embodiment as it is.

[0354] Reference Fig.39 , the first surface 127G may include first regions 127G-1 having grooves 128 (disposed in the first regions 127G-1) and second regions 127G-2 disposed between the first regions 127G-1.

[0355] The diameter of the first region 127G-1 may be 1.0 to 1.5 times the diameter of the groove 128. When the diameter of the first region 127G-1 exceeds 1.5 times the diameter of the groove 128, the area of ​​the second electrode 246 is so small that current diffusion efficiency may be reduced. The first region 127G-1 may be a region between the second electrode 246 and the groove 128.

[0356] The second region 127G-2 may be a remaining region except for the first region 127G-1. The second electrode 246 may be entirely disposed on the second region 127G-2.

[0357] The second electrode 246 may include a metal or a metal oxide having a low resistance. Therefore, the second electrode 246 absorbs ultraviolet light. Therefore, it is necessary to reduce the amount of light absorbed by the second electrode 246 by reducing the area of ​​the second electrode 246.

[0358] The second conductive layer 150 is disposed on the first region 127G-1 and the second region 127G-2, so light incident on the first region 127G-1 can be reflected by the second conductive layer 150. Therefore, light extraction efficiency can be improved by reducing the area of ​​the second region 127G-2 where the second electrode 246 is disposed and increasing the area of ​​the first region 127G-1. In this case, it is important to maximize the reflection area while ensuring the area of ​​the second electrode 246 required for diffusion current.

[0359] The area of ​​the second region 127G-2 may be in the range of 35% to 60% of the maximum area of ​​the light emitting structure 120. When the area of ​​the second region 127G-2 is less than 35%, the contact area of ​​the second electrode 246 is so small that the current diffusion efficiency may be reduced. Also, when the area of ​​the second region 127G-2 exceeds 60%, the area of ​​the first region 127G-1 is so small that the light extraction efficiency may be reduced.

[0360] The area of ​​the first region 127G-1 may be in the range of 10% to 55% of the maximum area of ​​the light emitting structure 120. When the area of ​​the first region 127G-1 is less than 10%, it is difficult to have sufficient reflection efficiency. When the area of ​​the first region 127G-1 is greater than 55%, the area of ​​the second region 127G-2 is so small that the current injection efficiency may be reduced.

[0361] Therefore, the ratio of the area of ​​the first region 127G-1 to the area of ​​the second region 127G-2 can be in the range of 1:0.7 to 1:6. When this relationship is satisfied, the current spreading efficiency is sufficient, so the light output power can be improved. Moreover, a sufficient reflection area is ensured, so the light extraction effect can be improved.

[0362] Fig.40 is along Fig.39 Cross-sectional view taken from CC.

[0363] The first surface 127G of the second conductive semiconductor layer may include a 1-1 surface S10 disposed between centers of two first and second grooves 128a and 128b that are most adjacent to each other in the first direction (X direction). In this case, the first direction may be a direction perpendicular to the thickness direction of the light emitting structure 120.

[0364] The 1-1 surface S10 may include a first portion S21 and second portions S22a and S22b disposed between the first portion S21 and the first and second grooves 128a and 128b.

[0365] The second portions S22a and S22b may include a 2-1 portion S22a disposed between the first portion S21 and the first groove 128a and a 2-2 portion S22b disposed between the first portion S21 and the second groove 128b.

[0366] The second electrode 246 may be disposed in the first portion S21. When the second electrode 246 is disposed only in the second portions S22a and S22b, the current density of the second portions S22a and S22b may increase, but the current density of the first portion S21 may be relatively reduced. Moreover, when the second electrode 246 is disposed in all portions of the first portion S21 and the second portions S22a and S22b, light absorption may occur in all portions of the first portion S21 and the second portions S22a and S22b. This may be detrimental to light extraction efficiency.

[0367] The second conductive layer may be disposed in the first portion S21 and the second portions S22a and S22b. Therefore, the second portions S22a and S22b where the second electrode 246 is not disposed may perform a reflective function.

[0368] According to one embodiment, it is important to appropriately determine the distance between the first electrode 142 and the second electrode 246 to ensure light extraction efficiency while ensuring a current density required for light emission.

[0369] For example, when the area of ​​the first electrode 142 is large, the current diffusion region becomes wider, so the area of ​​the second parts S22a and S22b can be increased. Therefore, the reflection area can be widened. However, when the area of ​​the first electrode 142 is small, the current diffusion region becomes narrower, so the second parts S22a and S22b can be narrowed.

[0370] The ratio of the width of the 2-1 portion S22b in the first direction to the diameter W1 of the first groove 128a may be in the range of 1:1.25 to 1:14. When the ratio is less than 1:1.25, the diameter of the groove 128 is reduced, and thus the area of ​​the first electrode 142 is reduced. Therefore, the intensity of the current injected through the first electrode 142 is weakened, and thus the current density of the second portions S22a and S22b may be reduced.

[0371] When the ratio is greater than 1:14, the diameter of the groove 128 excessively increases, and thus the area of ​​the first surface 127G of the second conductive semiconductor layer decreases. That is, the width of the 1-1 surface S10 decreases. Thus, the area of ​​the active layer 126 decreases, and thus the light emitting region decreases.

[0372] The diameter W1 of the groove 128 may be in the range of 20 μm to 70 μm. When the diameter of the groove 128 is less than 20 μm, it is difficult to ensure a process margin for forming the first electrode 142 disposed in the groove. When the diameter of the groove 128 is greater than 70 μm, the area of ​​the active layer 126 is so small that the light emitting efficiency may be deteriorated. Here, the diameter of the groove 128 may be the maximum diameter formed on the first surface 127G of the second conductive semiconductor layer.

[0373] The width of the first portion S21 in the first direction may be in the range of 6 μm to 12 μm. When the width is less than 6 μm, the area of ​​the second electrode 246 is so small that the current diffusion efficiency may be reduced. When the width is greater than 12 μm, the second portions S22a and S22b are so small that the reflection efficiency may be reduced.

[0374] The width of the 2-1 portion S22a and the 2-2 portion S22b in the first direction may be in the range of 5 μm to 16 μm. That is, the entire width of the second portions S22a and S22b may be in the range of 10 μm to 32 μm. When the width of the 2-1 portion S22a and the 2-2 portion S22b in the first direction is less than 5 μm, it is difficult to ensure a sufficient reflection area. When the width is greater than 16 μm, the second electrode 246 becomes narrower.

[0375] The ratio of the width of the first portion S21 to the entire width of the second portions S22a and S22b may be in the range of 1:0.8 to 1:5. When the width ratio range is satisfied, the ratio of the area of ​​the first region 127G-1 to the area of ​​the second region 127G-2 may be adjusted to be in the range of 1:0.8 to 1:6. Therefore, the current spreading efficiency and the light extraction effect may be improved.

[0376] The first portion S21 may include a point corresponding to 1 / 2 of the 1-1 surface S10. Since the second electrode 246 is disposed at the center of the 1-1 surface S10, the current density of the first portion S21 may be increased. Moreover, since the current density of the first portion S21 increases, the current is diffused in the second portions S22a and S22b disposed therebetween, and the current density required for light emission may be ensured. However, the present invention is not limited thereto. When the diameter of the first groove 128a is different from the diameter of the second groove 128b, the first portion S21 may deviate from the point corresponding to 1 / 2 of the 1-1 surface S10.

[0377] Fig.41 yes Fig.40 The first modification example. Fig.42 yes Fig.40 The second modification example.

[0378] The second conductive layer 150 may include a reflective groove 150-2 in the second portions S22a and S22b. Light incident on the second portions S22a and S22b may be reflected along a propagation path changed by the inclined surface of the reflective groove 150-2. According to this configuration, light uniformity may be improved.

[0379] The depth of the reflective groove 150-2 may be the same as the thickness of the first insulating layer 131. The thickness of the first insulating layer 131 may be equal to 110% to 130% of the thickness of the second electrode 246. As described above, the thickness of the second electrode 246 may be in the range of 1nm to 15nm.

[0380] The light-transmitting layer 131b may be disposed in the reflective groove 150-2. The shape of the light-transmitting layer 131b may correspond to the shape of the reflective groove 150-2. Therefore, the light-transmitting layer 133b may have the same thickness as the reflective groove 150-2. For example, the reflective groove 150-2 may be formed by forming the second conductive layer 150 on the light-transmitting layer 131b.

[0381] The material of the light-transmitting layer 131b may include various materials that can transmit light of ultraviolet wavelengths. For example, the light-transmitting layer 131b may include an insulating layer material. The light-transmitting layer 131b may include SiO2, Si x O y 、Si3N4、Si x Ny 、SiO x N y , Al2O3, TiO2 and AlN, but not limited thereto.

[0382] The light-transmitting layer 131b may be formed of the first insulating layer 131 disposed in the first groove 128a (extending to the second conductive semiconductor layer). However, the present invention is not limited thereto, and a separate dielectric layer may be disposed.

[0383] Reference Fig.42 , the second electrode 246 may have a density that decreases away from the center point of the 1-1 surface S10. That is, the separated second electrodes 246, 246d, and 246e may be arranged to have a size that decreases away from the center. The separated second electrodes 246c, 246d, and 246e may be manufactured by selective etching with the aid of a mask.

[0384] According to such a configuration, the current density of the second portions S22a and S22b can be increased while maintaining the current density of the first portion S21. Moreover, by maintaining the area ratio of the first portion S21 to the second portions S22a and S22b in the range of 1:0.8 to 1:6, current diffusion efficiency and reflection efficiency can be obtained.

[0385] Fig.43 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention.

[0386] The semiconductor device may be configured as a package and may be used for curing of a resin, a resist, SOD, or SOG. Alternatively, the semiconductor device may be used for medical treatment or may be used for disinfection of an air purifier or a water purifier.

[0387] refer to Fig.43 , a semiconductor device package may include a body 2 having a groove 3 , a semiconductor device 1 disposed in the body 2 , and a pair of lead frames 5 a and 5 b disposed in the body 2 and electrically connected to the semiconductor device 1 .

[0388] 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, and 2d. The plurality of layers 2a, 2b, 2c, and 2d may be made of the same material or include different materials.

[0389] The groove 3 may have a width that increases as it becomes farther away from the semiconductor device, and may have an inclined surface having a step portion formed therein.

[0390] 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 material of the light-transmitting layer 4 is not particularly limited as long as the material can effectively transmit ultraviolet light. The groove 3 may have an empty space formed therein.

[0391] The semiconductor device can be used as a light source of a lighting system, a light source of an image display device, or a light source of a lighting device. That is, the semiconductor device can be applied to various electronic devices that are configured to be provided in their housings to provide light. For example, when a semiconductor device and an RGB phosphor are mixed and used, white light with a high color rendering index (CRI) can be achieved.

[0392] The semiconductor device described above may be configured as a light emitting device package and used as a light source of a lighting system. For example, the semiconductor device may be used as a light source of an image display device or a light source of a lighting device.

[0393] When the semiconductor device is used as a backlight unit of an image display device, the semiconductor device can be used as an edge-type backlight unit or a direct-type backlight unit. When the semiconductor device is used as a light source of an illumination device, the semiconductor device can be used as a lamp or a light bulb. Alternatively, the semiconductor device can be used as a light source of a mobile terminal.

[0394] Fig.44 is a plan view of a semiconductor device according to a sixteenth embodiment. Fig.45 is along Fig.44 A cross-sectional view of a semiconductor device taken along line H-H', Fig.46 It is shown Fig.45 Detailed view of a part of.

[0395] for Fig.44 In the semiconductor device, the first electrode 242 and the second conductive layer 250 can be respectively disposed inside and outside the plurality of grooves, the reflective layer can be disposed outside the edge region of the semiconductor device, and the reflective layer can be formed by extending the second conductive layer 250.

[0396] In the semiconductor device, a structure consisting of a plurality of first electrodes, grooves and a second conductive layer (first reflective layer) can actually be set, and the number of grooves can be freely adjusted in consideration of the size, current density and optical power of the semiconductor device.

[0397] The semiconductor device 200A according to this embodiment may include: a semiconductor structure 220 including a first conductive semiconductor layer 222 , an active layer 224 , and a second conductive semiconductor layer 226 ; a first electrode 242 contacting the first conductive semiconductor layer 222 ; and a second electrode 246 contacting the second conductive semiconductor layer 226 .

[0398] There may be a plurality of regions in which grooves are provided in the second conductive semiconductor layer 226, the active layer 224, or even a portion of the first conductive semiconductor layer 226 to expose the first conductive semiconductor layer 222. These regions may be referred to as groove regions. The groove regions have cross-sections having shapes such as circular, polygonal, and elliptical, but are not limited thereto.

[0399] The first electrode 242 may be disposed under the first conductive semiconductor layer 222 exposed in the groove region, and the second electrode 246 may be disposed on a lower surface of the second conductive semiconductor layer 226 between the groove regions.

[0400] The first conductive semiconductor layer 222 may be made of a group III-V or group II-VI compound semiconductor and may be doped with a first conductive dopant. x In y Ga 1-x-y The invention can be grown in any one of the semiconductor materials of N (0≤x≤1, 0≤y≤1, 0≤x+y≤1), such as AlGaN, GaN, InAlGaN, AlGaAs, GaP, GaAs, GaAsP and AlGaInP.

[0401] When the first conductive semiconductor layer 222 is an n-type semiconductor layer, the first conductive dopant may include n-type dopants such as Si, Ge, Sn, Se, and Te. The first conductive semiconductor layer 222 may be grown as a single layer or multiple layers, but is not limited thereto.

[0402] The active layer 224 may include any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure.

[0403] The active layer 224 may be formed as a pair structure of a well layer and a barrier layer, for example, by using a group X compound semiconductor material AlGaN / AlGaN, InGaN / GaN, InGaN / InGaN, AlGaN / GaN, InAlGaN / GaN, GaAs (InGaAs) / AlGaAs, or GaP (InGaP) / AlGaP, but is not limited thereto. The well layer may be formed of a material having a smaller energy band gap than that of the barrier layer.

[0404] The second conductive semiconductor layer 226 may be made of a group III-V or group II-VI compound semiconductor and may be doped with a second conductive dopant. x In y Ga 1-x-y N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) semiconductor materials, such as AlGaN, GaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP.

[0405] When the second conductive semiconductor layer 226 is made of AlGaN, hole injection may not be convenient due to the low conductivity of AlGaN. This problem can be solved by providing GaN having a relatively high conductivity on the bottom surface of the second conductive semiconductor layer 226.

[0406] When the second conductive semiconductor layer 226 is a p type semiconductor layer, the second conductive dopant may include a p type dopant such as Mg, Zn, Ca, Sr, and Ba. The second conductive semiconductor layer 226 may be formed as a single layer or a multilayer, but is not limited thereto.

[0407] A square wave pattern may be formed on an upper surface of the first conductive semiconductor layer 222. The square wave pattern may improve extraction efficiency of light emitted from the semiconductor device 200A.

[0408] The width may increase from the first conductive semiconductor layer 222 to the active layer 224 to the electron blocking layer to the second conductive semiconductor layer 226. This is because the lower structure of the light emitting structure 220 may be etched to have a larger width during the etching process.

[0409] The light emitting structure 220 may have a height range of, for example, 2 to 3 μm. When the light emitting structure 220 emits ultraviolet light, the square wave pattern of the upper surface may have a depth range of 3,000 to 8,000 angstroms and an average depth of about 5,000 angstroms to improve the extraction efficiency of short wavelength light shorter than blue wavelength.

[0410] The first insulating layer 231 may be disposed at a distance from the first electrode 242. The first insulating layer 231 may extend from the exposed surface of the first conductive semiconductor layer 22 to the side surface of the groove region, and thus may even be disposed within the surface of the second conductive semiconductor layer 226. The first insulating layer 231 may be disposed on the exposed lower surface of the second conductive semiconductor layer 246, at a distance from both ends of the second electrode 246.

[0411] The first insulating layer 231, the second insulating layer 232 and the passivation layer 280 may be made of an insulating material. As the insulating material, aluminum oxide or aluminum nitride may be used. For example, the first insulating layer 231, the second insulating layer 232 and the passivation layer 280 may contain SiO2 or SiN, but are not limited thereto.

[0412] The second conductive layer 250 may be disposed on the lower surface of the second conductive semiconductor layer 226. The second conductive layer 250 may be made of a conductive material such as a metal. In detail, the second conductive layer 250 may be made of at least one material selected from chromium (Cr), aluminum (Al), titanium (Ti), gold (Au), and nickel (Ni), or an alloy thereof.

[0413] For example, assume that the second conductive layer 250 is made of aluminum and ultraviolet wavelength light is emitted from the active layer 224. In this case, when the second conductive layer 250 has a thickness greater than or equal to 50 nm, the thickness is sufficient to reflect 80% or more of the ultraviolet wavelength light.

[0414] The second conductive layer 250 may be used as a cover layer, and is configured to electrically connect the second electrode 246 to the second electrode pad 266 and surround and support the second electrode 246 to ensure the stability of the second electrode 246. In addition, the second conductive layer 250 may be provided to surround at least a portion of the bottom surface and the side surface of the insulating layer. The second conductive layer 250 may have a high adhesive strength with the insulating layer, thereby ensuring device reliability.

[0415] Specifically, the semiconductor device 200A emitting UV-B or UV-C wavelength light has a light emitting structure grown based on AlGaN, and thus the amount of light emitted can be increased in the TM mode in which light is emitted in a direction perpendicular to the growth direction of the light emitting structure 220 (i.e., Figure 5 In this case, the light traveling laterally in the active layer 224 can be reflected by the second conductive layer 250 to reduce light absorption in the light emitting structure 220, thereby changing the direction of the light and shortening the path of the light.

[0416] To this end, the second conductive layer 250 may extend from an edge region of the light emitting structure 220 to a region higher than the active layer 224 .

[0417] Reference Fig.46 , the edge region of the light emitting structure 220 may be exposed by removing a portion of the second conductive semiconductor layer 226, the active layer 224, and the first conductive semiconductor layer 222. The second conductive layer 250 may be disposed in the region where the light emitting structure 220 has been removed.

[0418] exist Fig.46, the region indicated by line II' is the end of the light emitting structure 220 and may refer to the interval region of the light emitting structure 220. The region indicated by line JJ' may be a region of the surface of the light emitting structure 220, that is, the second conductive semiconductor layer 226 has not been removed and the upper surface remains. The edge region of the light emitting structure may indicate the outside of the region indicated by line JJ'.

[0419] Here, the distance d1 between the line II' and the line JJ' may be in the range of 3 μm to 7 μm, for example, the distance may be 5 μm. When the distance between the line II' and the line JJ' is less than 3 μm, the mesa etching region becomes narrow, and thus it may be difficult to form the second conductive layer 250 to have a stepped structure. When the distance is greater than 7 μm, process stability is improved, but the volume of the active layer 224 may be reduced.

[0420] The second electrode pad 266 may be made of a conductive material or a metal and have a single layer structure or a multi-layer structure. In detail, the second electrode pad 266 may have a structure of titanium (Ti) / nickel (Ni) / Ti / Ni / Ti / gold (Au).

[0421] The second electrode pad 266 can be used to reflect light. Therefore, as the second electrode pad 266 is closer to the semiconductor structure 220, the light extraction efficiency can be better improved. The distance d2 between the area represented by the second electrode pad 266 and the line II' and the end of the light emitting structure 220 can be in the range of 20μm to 30μm. When the distance d2 is less than 20μm, it may be difficult to form the second insulating layer 280 and ensure the process margin. When the distance d2 is greater than or equal to 30μm, the second electrode pad 266 is too far away from the light emitting structure 220 so that the light extraction efficiency may be reduced.

[0422] In order to electrically connect the second electrode pad 266 to the second conductive layer 250, the second electrode pad 266 is disposed after forming a groove on at least one of the first insulating layer 231 and the passivation layer 280. In this case, the second electrode pad 266 may be formed along a step portion of at least one of the first insulating layer 231 and the passivation layer 280. When the second electrode pad 266 is formed along a low step portion, the upper surface of the second electrode pad 266 may be concave or convex relative to the substrate. When the second electrode pad 266 is bonded to the wire, the concave or convex surface may increase the bonding area, thereby improving the adhesive strength therebetween.

[0423] The depth h1 of the groove region may be the same as the depth h3 where the light emitting structure 220 has been removed, so as to dispose the second conductive layer 250 in the edge region of the light emitting structure 220 .

[0424] In addition, the side surface of the light emitting structure 220, especially the side surface of the second conductive semiconductor layer 226 may form an angle θ1 with the lower surface, and the side surface of the second conductive layer 250 may form an angle θ2 with the lower surface. Here, the angles θ1 and θ2 have the same value.

[0425] The inclined structure of the second conductive layer 250 may be formed by obliquely removing the edge of the light emitting structure 220 by mesa etching or the like, and may be configured to allow light emitted from the active layer 224 to travel toward an upper portion of the light emitting device 200A. Fig.46 , the angles θ1 and θ2 may be greater than 90 degrees and less than 150 degrees.

[0426] The distance d3 of the area where the lower surface of the second conductive semiconductor layer 226 and the first insulating layer 231 contact each other may be, for example, in the range of 5 μm to 15 μm. When the distance d3 is less than 5 μm, it may be difficult to ensure the process margin. When the distance d3 is greater than 15 μm, the setting area of ​​the second electrode 246 is so small that the operating voltage of the device may increase. Moreover, the distance d4 of the area where the second insulating layer 231 and the second conductive layer 250 overlap each other on the lower surface of the second conductive semiconductor layer 226 may be, for example, in the range of 4 μm to 8 μm. When the distance d4 is less than 4 μm, it is difficult to ensure the process margin of the overlap between the second conductive layer 250 and the first insulating layer 231. When the distance d4 is greater than 8 μm, it is difficult to ensure the process margin of electrical separation from the first electrode 242.

[0427] The second insulating layer 232 may be disposed under the second conductive layer 250 and the first insulating layer 231. The second insulating layer 232 contacts the first conductive semiconductor layer 222 in the groove region and covers the first electrode 242.

[0428] The second insulating layer 231 may be used to electrically isolate the first electrode from the second electrode 246. The thickness of the second insulating layer 232 may be in the range of 5,000 angstroms to 13,000 angstroms. When the thickness of the second insulating layer 232 is less than 5,000 angstroms, the thickness is insufficient to electrically separate the first electrode 242 from the second electrode 246, and thus reliability may be reduced. When the thickness is greater than 13,000 angstroms, stress occurring during bonding of the support substrate 270 is so great that reliability may be reduced.

[0429] According to the shape of the light emitting structure and the groove area, the first conductive layer 265 and the junction layer 260 may be disposed on the lower surface of the second insulating layer. The first conductive layer 265 in the first groove area may contact the first electrode 242 through the opening of the second insulating layer 232 .

[0430] The first conductive layer 265 may be made of a material having high reflectivity such as aluminum (Al). In the ultraviolet wavelength region, when the thickness is greater than or equal to 500 angstroms, a light reflectivity of 80% or more may be ensured.

[0431] The junction layer 260 may be a region including a region where the first conductive layer 265 is diffusion-bonded or eutectic-bonded to the support substrate 270 therebelow. In this region, Ni, Sn, Au, and the like are mixedly present.

[0432] The junction layer 260 may have a protrusion formed along a step portion on the bottom surface in the thickness direction of the semiconductor device, which protrusion appears within a spacing distance d0 between the first insulating layer 231 and the second electrode 246 disposed on the bottom surface of the second conductive semiconductor layer 226. When the thickness is sufficient, the junction layer 260 may have a flat bottom surface.

[0433] In addition, a spacing distance d0 between the second electrode 246 and the first insulating layer 231 may be in the range of, for example, 1 μm to 2 μm. The second conductive semiconductor layer 226 may contact the second conductive layer 250 within the spacing distance d0. The spacing distance d0 may be secured by self-alignment.

[0434] The junction layer 260 may include a conductive material. For example, the junction layer 260 may be formed of a material selected from the group consisting of gold (Au), tin (Sn), indium (In), aluminum (Al), silicon (Si), silver (Ag), (Ni) and copper (Cu) or an alloy thereof. The diffusion barrier layer prevents the material forming the junction layer 260 from diffusing to the vicinity of the first electrode 242, thereby reducing reliability during the bonding process.

[0435] A diffusion barrier layer (not shown) may be disposed between the first conductive layer 265 and the junction layer 260 and may have a multi-layer structure such as titanium / nickel / titanium / nickel.

[0436] The support substrate 270 may be made of a conductive material. For example, the support substrate 270 may be formed of a metal or a semiconductor material. The material of the support substrate 270 may be a metal having high electrical conductivity and thermal conductivity. Because the heat generated during the operation of the light emitting device should be fully radiated, the support substrate 270 may be formed of a material having high thermal conductivity. For example, the support substrate 270 may be made of a material selected from the group consisting of silicon (Si), molybdenum (Mo), tungsten (W), copper (Cu) and aluminum (Al), or an alloy thereof. Moreover, the support substrate 270 may selectively include gold (Au), copper alloy (Cu alloy), nickel (Ni), copper-tungsten (Cu-W), a carrier wafer (e.g., GaN, Si, Ge, GaAs, ZnO, SiGe, SiC and Ga2O3), etc.

[0437] When a semiconductor device is formed based on AlGaN and contains a large amount of aluminum (Al), the current diffusion characteristics in the light emitting structure are degraded. In particular, a light emitting device emitting UV-B or UV-C wavelength light has a light emitting structure grown based on AlGaN containing a large amount of aluminum (Al), and thus the amount of polarized light can be increased in the TM mode, where light emission is dominated in a direction perpendicular to the growth direction of the light emitting structure, compared to a light emitting device configured to emit blue wavelength light. In this case, light traveling laterally in the active layer can be reflected by the second conductive layer 250.

[0438] Figure 47 to Figure 49 are detailed diagrams showing a portion of the semiconductor device according to seventeenth to nineteenth embodiments.

[0439] Fig.47 is a cross-sectional view of a portion of a semiconductor device according to a seventeenth embodiment. Here, the semiconductor device according to the seventeenth embodiment will be described, focusing on the differences from the semiconductor device according to the sixteenth embodiment.

[0440] The semiconductor device 200B according to this embodiment is different from the semiconductor device of the sixteenth embodiment in that a third reflective layer 238 is provided in the groove region.

[0441] The third reflective layer 238 may be made of at least one material selected from the group consisting of chromium (Cr), aluminum (Al), titanium (Ti), gold (Au), and nickel (Ni), or an alloy thereof. Assume that the third reflective layer 238 is made of aluminum and ultraviolet wavelength light is emitted from the active layer 224. In this case, when the third reflective layer 238 has a thickness greater than or equal to 50 nm, the thickness is sufficient to reflect ultraviolet wavelength light.

[0442] The third reflective layer 238 may have an upper surface electrically connected to the first electrode 242 and a lower surface electrically connected to the first conductive layer 265. Also, the third reflective layer 238 may be electrically isolated from the second conductive layer 250 by the second insulating layer 232.

[0443] In this case, the third reflective layer 238 may have a portion vertically overlapping the second conductive layer 250 under the second conductive semiconductor layer 226, thereby ensuring process stability. In addition, the third reflective layer 238 may sufficiently reflect light emitted from the active layer 224 toward the supporting substrate 270, thereby improving the light output power of the light emitting device.

[0444] Fig.48 is a cross-sectional view of a portion of a semiconductor device according to an eighteenth embodiment. Here, the semiconductor device according to the eighteenth embodiment will be described, focusing on the differences from the semiconductor device according to the seventeenth embodiment.

[0445] exist Fig.48 , a height h52 from the bottom surface of the light emitting structure 220 to the top surface of the third reflective layer 238 may be greater than a height h51 from the bottom surface of the light emitting structure 220 to the active layer 224. In other words, a portion of the third reflective layer 238, that is, an upper region of the third reflective layer 238 may be disposed at a height corresponding to the first conductive semiconductor layer 222, and a lower region of the third reflective layer 238 may be disposed to face the bottom surface of the second conductive semiconductor layer 226 from the bottom of the groove region. Also, a middle region of the third reflective layer 238 may be disposed at a height corresponding to the active layer 224 and inclined with respect to the bottom surface of the second conductive semiconductor layer 226. In this case, light emitted from the active layer 224 may be particularly reflected by the middle region of the third reflective layer 238.

[0446] In the semiconductor device 200C according to this embodiment, the upper region of the third reflective layer 238 may have a top surface in contact with the first electrode 142 to be electrically connected to the first conductive semiconductor layer 222 and a bottom surface in contact with the first conductive layer 265. However, the middle region and the lower region of the third reflective layer 238 may be disposed to surround the second insulating layer 232.

[0447] Fig.49 is a cross-sectional view of a portion of a semiconductor device according to a nineteenth embodiment. Here, a semiconductor device according to the nineteenth embodiment will be described, focusing on differences from the semiconductor devices according to the above-described embodiments.

[0448] In the semiconductor device 200D according to this embodiment, the conductive layer 228 may be provided under the second conductive semiconductor layer 226. When the second conductive semiconductor layer 226 is made of AlGaN, hole injection may not be convenient due to the low conductivity of AlGaN. This problem can be solved by providing a conductive layer 228 containing GaN having relatively high conductivity.

[0449] The junction layer 260 contacts the first conductive semiconductor layer 222 through the first groove. Although not shown, a first electrode layer may be disposed between the junction layer 260 and the first conductive semiconductor layer 222.

[0450] The second reflective layer 235 is disposed in the second groove, and the insulating layer 230 is disposed to extend to the upper surface and even the side surface of the second reflective layer 235. In the junction layer 260, the second groove (having the second reflective layer 235 disposed therein) may have the same height as the first groove, which contacts the first conductive semiconductor layer 222, and have a smaller width than the first groove.

[0451] The insulating layer 230 may be disposed on the top of the second reflective layer 235 , and the junction layer 260 may be disposed on the bottom of the second reflective layer 235 and electrically connected to the second reflective layer 235 .

[0452] Fig.50 is a plan view of a semiconductor device according to a twentieth embodiment. Fig.51 is along Fig.50 Here, the semiconductor device according to the twentieth embodiment will be described, focusing on the differences from the semiconductor device according to the sixteenth embodiment.

[0453] In the semiconductor device 200E, the reflective layer 235 may be disposed in a low current density region between the first electrodes 242 and between the grooves. The low current density region may be separated from the first electrode 242 by a distance r0. In the semiconductor device 200E, in practice, a greater number of structures may be disposed, each of which is formed by the first electrode 242 and the grooves, and the number of structures may be designed in consideration of the current density, so this document has no limitation thereto. By disposing the structure in consideration of the current of the first electrode, a low current density region may be designed and a second reflective layer may be disposed in the low current density region. The second reflective layer 235 may be formed by the first electrode 242 and the grooves. Figure 46 to Figure 49 The third reflective layer 238 is formed of the same material.

[0454] exist Fig.50 In FIG. 1 , the plurality of first electrodes 242 are shown as circles, and a region spaced apart from the first electrodes by a distance r0 may be referred to as a “boundary region.” The boundary region may have a current density Ii.

[0455] The shape of the boundary region may be circular, but may vary depending on the shape of the first electrode 242. Therefore, the present invention is not limited thereto. The current density Ii of the boundary region may be in the range of 30% to 40% of the current density I0 (eg, Ii=I0×exp(-1)).

[0456] In addition, the low current density region may refer to a region between a plurality of boundary regions and may have a current density less than the current density Ii.

[0457] In this embodiment, the second reflective layer is arranged to contact the outside of the "border area" surrounding one first electrode 242, and a plurality of "border areas" may directly contact each other or be spaced apart from each other. Therefore, when the boundary areas are in contact with each other, the low current density areas may be spaced apart from each other, and when the boundary areas are spaced apart from each other, the low current density areas may expand.

[0458] exist Fig.51In the embodiment, a groove is provided from the second conductive semiconductor layer 226 to a portion of the active layer 224 and the first conductive semiconductor layer 226, and there are a plurality of regions exposing the first conductive semiconductor layer 222, which are classified into a first groove region and a second groove region. The cross-sections of the first groove region and the second groove region are, for example, circular, polygonal, elliptical, etc., but are not limited thereto. The second groove region may be provided around the first groove region.

[0459] The first electrode 242 may be disposed on the first conductive semiconductor layer 222 exposed in the first groove region, and the second electrode 246 may be disposed on the second conductive semiconductor layer 226 between the first groove region and the second groove region. Moreover, the second reflective layer 235 may be inserted into the second groove region, and a portion of the second reflective layer 235 may extend to an area outside the second groove region. A portion of the second reflective layer 235 may be disposed at a height corresponding to the active layer 224, and the height corresponds to a portion of the first conductive semiconductor layer 222. That is, the top surface of the second reflective layer 235 may be disposed at the same height as that of the active layer 224.

[0460] The light emitting structure 220 is based on AlGaN and contains a large amount of aluminum (Al), and the current diffusion characteristics are deteriorated in the light emitting structure 220. In this case, the light emitting structure 220 is removed from the low current density area, and the second reflective layer 235 is formed. Moreover, the second reflective layer 235 can change the path of the light emitted from the active layer upward in the TM mode to reduce the light absorption in the light emitting structure. Therefore, the orientation angle of the semiconductor device can be adjusted and the light extraction efficiency can be improved.

[0461] In addition, the second conductive layer 250 may be used as a cover layer, and is configured to electrically connect the second electrode 246 to the second electrode pad 266 and surround and support the second electrode 246 and the second reflective layer 235 to ensure stability thereof. In particular, similar to the sixteenth embodiment, the edge region of the light emitting structure 220 may be exposed by removing a portion of the second conductive semiconductor layer 226, the active layer 224, and the first conductive semiconductor layer 222, the second conductive layer 250 may be disposed in a region from which the light emitting structure 220 has been removed, and the second conductive layer 250 may extend to a region higher than the active layer.

[0462] That is, the edge region of the light emitting structure 220 is exposed by removing a portion of the second conductive semiconductor layer 226, the active layer 224, and the first conductive semiconductor layer 222, and the second conductive layer 250 may be disposed in the region where the light emitting structure 220 has been removed.

[0463] exist Fig.51, the area indicated by line II' is the end of the light emitting structure 220 and may refer to the interval area of ​​the light emitting structure 220. The area indicated by line JJ' may be an area of ​​the surface of the light emitting structure 220, that is, the second conductive semiconductor layer 226 has not been removed and the upper surface remains.

[0464] Here, the distance d1 between the line II' and the line JJ' may be in the range of 3 μm to 7 μm, for example, the distance may be 5 μm. When the distance between the line II' and the line JJ' is less than 3 μm, the mesa etching region becomes narrow, and thus it may be difficult to form the second conductive layer 250 to have a stepped structure. When the distance is greater than 7 μm, process stability is improved, but the volume of the active layer 224 may be reduced.

[0465] According to the semiconductor device 200E of the present embodiment, the second reflective layer 235 in the low current density region is disposed in the second groove region and is configured to reflect upward the light emitted from the active layer 224 and traveling laterally, and the second conductive layer 250 in the edge region of the light emitting structure 220 can extend to a height greater than the height of the active layer 224 and reflect upward the light emitted from the active layer and traveling to the edge region.

[0466] Semiconductor devices can be configured as packages and can be used for curing of resins, resists, SODs or SOGs. Alternatively, semiconductor devices can be used for medical treatment or can be used for disinfection of air purifiers or water purifiers. Moreover, semiconductor devices can be used as light sources for lighting systems. For example, semiconductor devices can be used as light sources for image display devices or light sources for lighting devices.

[0467] When the semiconductor device is used as a backlight unit of an image display device, the semiconductor device can be used as an edge-type backlight unit or a direct-type backlight unit. When the semiconductor device is used as a light source of an illumination device, the semiconductor device can be used as a lamp or a light bulb. Alternatively, the semiconductor device can be used as a light source of a mobile terminal.

[0468] Fig.52 is a diagram showing a package in which a semiconductor device is provided.

[0469] The light emitting device package 300 according to the embodiment includes a package body 310 , a first electrode unit 321 , a second electrode unit 322 , and a light emitting device 200A.

[0470] The package body 310 may be made of an insulating material having a cavity, and may include, for example, polyphthalamide (PPA) resin, a silicon-based material, or the like.

[0471] The first electrode unit 321 and the second electrode unit 322 may be disposed on the package body 310 , and a portion of the electrode may be disposed on the bottom of the cavity.

[0472] The light emitting device 200A may be the above-mentioned light emitting device, and may be disposed on the first electrode unit 321 and electrically connected to the second electrode unit 322 through the wire 330 .

[0473] The periphery of the light emitting device 200A and the wire 330 may be filled with air. For a light emitting device emitting ultraviolet light, when a molding part made of a silicon-based material is disposed at the periphery of the light emitting device, defects such as cracks may occur in the molding part due to energy corresponding to the wavelength of ultraviolet light, and thus reliability may be reduced.

[0474] A phosphor (not shown) may be included around the light emitting device 200A. The phosphor may be a YAG-based phosphor, a nitride-based phosphor, a silicate-based phosphor, or a mixture thereof, but is not limited thereto. A groove is formed on the package body 310, and a cover 370 is disposed on the groove. The cover 370 may be made of a light-transmitting material such as glass. An adhesive 375 may be used to combine the package body 310 and the cover 370. For example, a silicon-based adhesive may be used as the adhesive 375.

[0475] Apart from Fig.52 In addition to the package of the present invention, the semiconductor device is flip-chip bonded and used as a package.

[0476] Fig.53 is a plan view of a semiconductor device package according to an embodiment of the present invention, Fig.54 yes Fig.53 Modification example.

[0477] Reference Fig.53 , the semiconductor device 10 may be disposed on the first lead frame 5a and connected to the second lead frame 5b through a wire. In this case, the second lead frame 5b may be disposed to surround the side surface of the first lead frame.

[0478] Reference Fig.54 , the semiconductor device package may have a plurality of semiconductor devices 10a, 10b, 10c, and 10d disposed therein. In this case, 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.

[0479] The first semiconductor device 10a may be disposed on the first lead frame 5a and connected to the second lead frame 5b by means of a wire. The second semiconductor device 10b may be disposed on the second lead frame 5b and connected to the third lead frame 5c by means of a wire. The third semiconductor device 10c may be disposed on the third lead frame 5c and connected to the fourth lead frame 5d by means of a wire. The fourth semiconductor device 10d may be disposed on the fourth lead frame 5d and connected to the fifth lead frame 5e by means of a wire.

[0480] The semiconductor device can be applied to various light source devices. For example, conceptually, the light source device may include a lighting device and a display device. That is, the semiconductor device can be applied to various electronic devices that are configured to be provided in their housing to provide light.

[0481] The lighting device may include: a light source module including a substrate and a semiconductor device of an embodiment; a heat dissipation unit configured to dissipate heat of the light source module; and a power supply unit configured to process or convert an electrical signal from the outside and provide the electrical signal to the power supply module. Furthermore, the lighting device may include a lamp, a headlamp, or a street lamp.

[0482] 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.

[0483] The reflective plate may be placed on the bottom cover, and the light emitting module may emit light. The light guide plate may be placed in front of the reflective plate so as to guide the light emitted by the light emitting module forward. The optical sheet may include a prism sheet (brightness enhancement film) and the like, and may be placed in front of the light guide plate. The display panel may be placed in front of the optical sheet. The image signal output circuit may supply the image signal to the display panel. The color filter may be placed in front of the display panel.

[0484] 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 a direct-type backlight unit.

[0485] The semiconductor device may be a laser diode instead of the above-mentioned light emitting diode.

[0486] As a light-emitting device, a laser diode may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer having the above structure. The laser diode may also use a field luminescence phenomenon in which light is emitted when current flows after a p-type first conductive semiconductor and an n-type second conductive semiconductor contact each other, but the emitted light is different in directionality and phase. That is, the laser diode uses stimulated emission and constructive interference so that light with a specific single wavelength can be emitted in the same phase and direction. Due to these characteristics, laser diodes can be used in optical communication devices, medical devices, semiconductor processing devices, etc.

[0487] The light receiving device may include, for example, a photodetector, which is a transducer configured to detect light and convert the intensity of the light into an electrical signal. The photodetector may include a photocell (silicon and selenium), a light output element (cadmium sulfide and cadmium selenide), a photodiode (e.g., a PD having a peak wavelength in a visible blind spectral region or a true blind spectral region), a phototransistor, a photomultiplier tube, a phototube (vacuum and gas-filled), an infrared (IR) detector, etc., but is not limited thereto.

[0488] Generally, semiconductor devices such as photodetectors can be made of direct bandgap semiconductors with excellent photoelectric conversion efficiency. Optionally, the photodetector can have various structures. As the most commonly used structure, the photodetector can include a needle-type photodetector using a pn junction, a Schottky photodetector using a Schottky junction, a metal-semiconductor-metal (MSM) photodetector, etc.

[0489] Like a light emitting device, a photodiode may include a first conductive semiconductor layer and a second conductive semiconductor layer having the above structure, and may be formed into a pn junction or a needle-shaped structure. When a reverse bias or zero bias is applied, the photodiode operates. When light is incident on the photodiode, electrons and holes are generated, so that current flows. In this case, the current amplitude may be approximately proportional to the light intensity incident on the photodiode.

[0490] A photovoltaic cell or solar cell as a photodiode can convert light into electric current. Like a light emitting device, 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.

[0491] Furthermore, the solar cell can be used as a rectifier of an electronic circuit by using the rectification characteristics of a general diode of a pn junction and can be applied to an oscillation circuit of a microwave circuit or the like.

[0492] Moreover, the semiconductor device described above need not be implemented only with semiconductors. Depending on the circumstances, the semiconductor device may additionally include a metal material. For example, a semiconductor device such as a light receiving device may be implemented using at least one of Ag, Al, Au, In, Ga, N, Zn, Se, P, and As, and may be implemented using an intrinsic semiconductor material or a semiconductor material doped with a p-type dopant or an n-type dopant.

[0493] Although the present invention has been described with reference to exemplary embodiments, these are merely examples and are not intended to limit the present invention. It will be appreciated by those skilled in the art that various modifications and applications may be made therein without departing from the essential features of the embodiments. For example, the elements described in the above-described embodiments may be modified and implemented. In addition, the differences associated with these modifications and applications should be interpreted as being included in the scope of the present invention as defined by the appended claims.

Claims

1. A semiconductor device, comprising: substrate; A light emitting structure, comprising, in a thickness direction of the light emitting structure, a first conductive semiconductor layer, a second conductive semiconductor layer, an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer, and a plurality of grooves passing through the second conductive semiconductor layer and the active layer, and a portion of the first conductive semiconductor layer; a first electrode electrically connected to the first conductive semiconductor layer by contacting the first conductive semiconductor layer disposed on top surfaces of the plurality of grooves; a second electrode electrically connected to the second conductive semiconductor layer by contacting the second conductive semiconductor layer; a first conductive layer, electrically connected to the first electrode; as well as a second conductive layer, electrically connected to the second electrode, The second conductive semiconductor layer includes a 1-1 surface disposed between two grooves that are most adjacent to each other in a first direction, and the first direction is a direction perpendicular to a thickness direction of the light emitting structure, The 1-1 surface includes a first portion provided with a plurality of second electrodes spaced apart from each other in the first direction and a second portion provided between the plurality of second electrodes. Wherein, the second conductive layer covers the second electrodes and is located between adjacent second electrodes, wherein the width ratio of the second portion to the first portion in the first direction is in the range of 1:0.7 to 1:5, The width of the first portion in the first direction is in the range of 12 μm to 24 μm, and the width of the second portion in the first direction is in the range of 5 μm to 16 μm. The second conductive semiconductor layer has a first surface opposite to the second electrode, and the first surface includes the 1-1 surface. wherein the first surface includes a first contact area that is in contact with the second electrode and a second contact area that is not in contact with the second electrode, and Wherein, a ratio of the second contact area to the first contact area is in a range of 1:0.7 to 1:

6.

2. The semiconductor device according to claim 1, wherein The second portion includes a point corresponding to 1 / 2 of the width of the 1-1 surface in the first direction.

3. The semiconductor device according to claim 1, wherein The second conductive layer includes a reflective groove disposed in the second portion. The semiconductor device according to claim 3 , comprising a light-transmitting layer provided in the reflective groove.

5. The semiconductor device according to claim 1, comprising a sub-groove disposed in the second portion and a sub-reflective layer disposed in the sub-groove, in, The sub-reflection layer contains aluminum, and Wherein, the sub-reflective layer is electrically connected to the second electrode.

6. The semiconductor device according to claim 1, wherein The first surface includes AlGaN.

7. The semiconductor device according to claim 6, wherein: The second conductive layer comprises: a first intermediate layer containing at least one of chromium (Cr), titanium (Ti) and nickel (Ni); and The reflective layer contains aluminum.

8. A semiconductor device package, comprising a body, and a semiconductor device as claimed in any one of claims 1 to 7; The semiconductor device is disposed in the body.

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