Ultaviolet light emitting semiconductor device and method of manufacturing the same

Abstract

The present disclosure relates to an ultraviolet light-emitting semiconductor device and a method for manufacturing the same, comprising: a plurality of semiconductor regions having a first semiconductor region, a second semiconductor region, and an active region that emits ultraviolet light through the recombination of electrons and holes; a first ohmic contact portion that supplies one of electrons and holes to the first semiconductor region; and a second ohmic contact portion that supplies the other of electrons and holes to the second semiconductor region; wherein the first semiconductor region in contact with the first ohmic contact portion is made of AlGaN, and the first ohmic contact portion comprises a first lower ohmic electrode that is in ohmic contact with the first semiconductor region; and a first upper electrode formed on the first lower ohmic electrode while in contact with the first lower ohmic electrode and the first semiconductor region; and wherein the device comprises an insulating layer that electrically insulates the first upper electrode, the active region, and the second semiconductor region.

Description

Technology Field

[0001] The present disclosure relates, in general, to an ultraviolet light-emitting semiconductor device and a method for manufacturing the same, and in particular to an ultraviolet light-emitting semiconductor device with improved current diffusion and a method for manufacturing the same. Here, a semiconductor light-emitting device refers to a semiconductor photodetector that generates light through the recombination of electrons and holes, and a group III nitride semiconductor light-emitting device may be cited as an example. A group III nitride semiconductor is composed of a compound of Al(x)Ga(y)In(1-xy)N (0≤x≤1, 0≤y≤1, 0≤x+y≤1). A semiconductor light-emitting device according to the present disclosure may be a semiconductor chip, a semiconductor package, a semiconductor chip attached to a display cell, etc. Furthermore, the term "ultraviolet" here refers to light whose emission peak wavelength corresponds to the ultraviolet region. Background Technology

[0002] This section provides background information related to the present disclosure, which is not necessarily prior art.

[0003] FIG. 1 is a drawing showing an example of an ultraviolet light-emitting semiconductor device disclosed in US Patent Publication No. US11,600,755, wherein the ultraviolet light-emitting semiconductor device (100) includes a substrate (110), a buffer region (120), a first semiconductor region (130), an active region (140), a second semiconductor region (150), an insulating layer (160), a first ohmic electrode (170), a second ohmic electrode (180), a first pad electrode (210), and a second pad electrode (220).

[0004] FIGS. 2 and FIGS. 3 are drawings illustrating an example of a semiconductor light-emitting device as disclosed in US Patent Publication No. US10,158,047. The semiconductor light-emitting device comprises a substrate (10), a first semiconductor region (30), an active region (40), a second semiconductor region (50), a light-transmitting electrode (60), a first ohmic electrode (85), a second ohmic electrode (74), an insulating layer (65), a first pad electrode (80), a second pad electrode (70), a first electrical connection (81), and a second electrical connection (71). Unlike the example disclosed in FIG. 1, the second ohmic electrode (74) is formed over the entire second semiconductor region (50), and the first ohmic electrode (85) is formed in the form of a branch electrode (=finger electrode) over the perimeter of the first semiconductor region (30). This is to ensure that current is supplied smoothly over the entire device as the chip becomes larger.

[0005] FIG. 4 is a drawing showing another example of a semiconductor light-emitting device as disclosed in US Patent Publication No. US10,158,047, in which, unlike the example disclosed in FIG. 2 and FIG. 3, the first ohmic electrode (85) is formed in the form of a branch electrode inside the device.

[0006] FIGS. 5 to 7 are drawings illustrating an example of a semiconductor light-emitting device as disclosed in US Patent Publication No. US8,247,823, wherein the semiconductor light-emitting device (1) comprises a substrate (10), a buffer region (20), a first semiconductor region (31, 32), an active region (40), a second semiconductor region (51, 52), a light-transmitting electrode (60), a first ohmic electrode (85), a second ohmic electrode (74), a first insulating layer (65), a second insulating layer (66), a first pad electrode (80), a second pad electrode (70), a first electrical connection (81), and a second electrical connection (71). Unlike FIGS. 2 to 4, the first pad electrode (80) and the second pad electrode (70) are formed on the second insulating layer (66) rather than the first insulating layer (65), and the first electrical connection (81) and the second electrical connection (71) are formed on the first insulating layer (65) in the form of wiring (hereinafter referred to as 'first wiring electrode (81)' and 'second wiring electrode (71)'). The first wiring electrode (81) is electrically connected to the first ohmic electrode (85) through a via hole (65b) formed in the first insulating layer (65), and the first pad electrode (80) is electrically connected to the first wiring electrode (81) through a via hole (66b) formed in the second insulating layer (66). The second wiring electrode (71) is electrically connected to the second ohmic electrode (74) through a via hole (65a) formed in the first insulating layer (65), and the second pad electrode (70) is electrically connected to the second wiring electrode (71) through a via hole (66a) formed in the second insulating layer (66). This configuration differs in that current is supplied using a plurality of via holes (65b) and the first wiring electrode (81) instead of the finger-shaped first ohmic electrode (85) shown in FIGS. 2 to 4. Unexplained reference numeral 67 is a reflective film, and it is obvious that the insulating layer (91) can be formed as an ODR or DBR and the reflective film (60) can be omitted.

[0007] As pointed out in U.S. Patent Publication No. US10,158,047, unlike blue light-emitting group 3 nitride semiconductor devices that mainly use InGaN and GaN, ultraviolet light-emitting semiconductor devices mainly use AlGaN, and as the wavelength of ultraviolet light becomes shorter, AlGaN with a higher Al content is used, which requires a higher heat treatment temperature (e.g., 700°C or higher) for low contact resistance between the AlGaN constituting the first semiconductor region (30) and the first ohmic electrode (85).

[0008] However, during this high-temperature heat treatment process, rough irregularities are generated on the first ohmic electrode (85), which is composed of a combination of Cr, Ti, V, Ni, Al, Au, etc., as shown in FIG. 8, and this is a first insulating layer (65; e.g., SiO2, SiN) placed on the first ohmic electrode (85). x While causing problems with adhesion to Al2O3, cracks (CR) and / or voids may occur in the first insulating layer (65). Additionally, if particles are formed during the deposition of the first insulating layer (65) or if contaminants such as particles remain before the process of the first insulating layer (65), an area (P) in which the first insulating layer (65) is not properly formed may occur (see FIG. 11). Meanwhile, FIG. 9 shows cracks (CR) occurring in the first semiconductor region (30) when there is a sudden step difference due to etching or the like in the first semiconductor region (30). If metal diffusion or moisture or chemicals penetrate through these defects (CR, P) occurring in the first insulating layer (65), it causes problems with the reliability of the device.

[0009] FIGS. 10 and 11 are drawings illustrating another example of a conventional ultraviolet light-emitting semiconductor device, wherein the ultraviolet light-emitting semiconductor device comprises a substrate (10), a buffer region (20), a first semiconductor region (30), an active region (40), a second semiconductor region (50), a light-transmitting electrode (60), a first ohmic electrode (85a, 85b), a second ohmic electrode (74), an insulating layer (65), a first pad electrode (80), a second pad electrode (70), a first electrical connection (81a, 81b), and a second electrical connection (71a). The first ohmic electrode (85a) is formed along the perimeter of the etched and exposed first semiconductor region (30), and the first ohmic electrode (85b) is formed extending in the form of a branch electrode along the longitudinal direction from the center of the etched and exposed first semiconductor region (30), and the second ohmic electrode (74) is formed over the entire second semiconductor region (50), and the first electrical connection (81a) is electrically connected to the first ohmic electrode (85a), and the first electrical connection (81b) is electrically connected to the first ohmic electrode (85b). As previously noted, a crack (CR) has occurred in the first insulating layer (65) on the high-temperature heat-treated first ohmic electrodes (85a, 85b), and an area (P) where the first insulating layer (65) is not properly formed is also indicated. Inside the dotted circle, the crack (CR) is shown in a somewhat exaggeratedly enlarged manner for subsequent explanation. The problem to be solved

[0010] This is described at the end of 'Specific details for implementing the invention'. means of solving the problem

[0011] This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all of its features.

[0012] According to one aspect of the present disclosure, a method for manufacturing an ultraviolet light-emitting semiconductor device comprises: forming a plurality of semiconductor regions including a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region that emits ultraviolet light through the recombination of electrons and holes; and forming a plurality of first ohmic electrodes on the first semiconductor region and a second ohmic electrode on the second semiconductor region, wherein the method comprises heat treatment at 700°C or higher A step of forming a plurality of first ohmic electrodes and a plurality of second ohmic electrodes, forming a plurality of first ohmic electrodes in a first semiconductor region; a step of forming a first insulating layer on the plurality of first ohmic electrodes and a second ohmic electrode; a step of forming a first wiring electrode on the first insulating layer to be electrically connected to the plurality of first ohmic electrodes and a second wiring electrode to be electrically connected to the second ohmic electrode; a step of forming a second insulating layer on the first wiring electrode and the second wiring electrode; A method for manufacturing an ultraviolet light-emitting semiconductor device is provided, comprising the step of forming a first pad electrode to be electrically connected to a first wiring electrode and a second pad electrode to be electrically connected to a second wiring electrode on a second insulating layer; wherein one of a plurality of first ohmic electrodes is located below the first pad electrode and another of the plurality of first ohmic electrodes is located below the second pad electrode, and the plurality of first ohmic electrodes are not exposed through the space between the first pad electrode and the second pad electrode when viewed from above, and one of the plurality of first ohmic electrodes and another of the plurality of first ohmic electrodes are electrically connected through a first wiring portion of a first wiring electrode located above the first insulating layer and below the second insulating layer.

[0013] According to another aspect of the present disclosure, a method for manufacturing a semiconductor light-emitting device comprises: forming a plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region that emits light through the recombination of electrons and holes; forming a first pad electrode electrically connected to the first semiconductor region and a second pad electrode electrically connected to the second semiconductor region; and forming at least one insulating layer provided between the plurality of semiconductor regions and the first and second pad electrodes; and further comprising, prior to forming the first and second pad electrodes, forming a recovery insulating layer at least once by applying one of the ALD method and the iCVD method to the at least one insulating layer.

[0014] According to another aspect of the present disclosure, a method for manufacturing a semiconductor light-emitting device comprises: a plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region that emits light through the recombination of electrons and holes; a first pad electrode electrically connected to the first semiconductor region; a second pad electrode electrically connected to the second semiconductor region; and a semiconductor chip comprising at least one insulating layer provided between the plurality of semiconductor regions and the first and second pad electrodes; and a step of preparing an external substrate having a first electrode pad and a second electrode pad. A method for manufacturing a semiconductor light-emitting device is provided, comprising the step of attaching a semiconductor chip to an external substrate such that a first pad electrode is bonded to a first electrode pad and a second pad electrode is bonded to a second electrode pad; and further comprising the step of forming a recovery insulating layer at least once by applying one of the ALD method and the iCVD method to at least one insulating layer in the step of preparing the semiconductor chip, wherein a recovery insulating layer is formed at least once by applying one of the ALD method and the iCVD method to an external substrate to which the semiconductor chip is attached.

[0015] According to another aspect of the present disclosure, an ultraviolet light-emitting semiconductor device is provided, comprising: a plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region to emit ultraviolet light through the recombination of electrons and holes; a first ohmic contact portion supplying one of electrons and holes to the first semiconductor region; and a second ohmic contact portion supplying the other of electrons and holes to the second semiconductor region; wherein the first semiconductor region in contact with the first ohmic contact portion is made of AlGaN, and the first ohmic contact portion comprises a first lower ohmic electrode in ohmic contact with the first semiconductor region; and a first upper electrode formed on the first lower ohmic electrode while in contact with the first lower ohmic electrode and the first semiconductor region; and wherein the device comprises an insulating layer that electrically insulates the first upper electrode, the active region, and the second semiconductor region.

[0016] According to another aspect of the present disclosure, a method for manufacturing an ultraviolet emitting semiconductor device comprises: a plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region to emit ultraviolet light through the recombination of electrons and holes; a first ohmic contact portion having a first lower ohmic electrode and a first upper electrode to supply one of electrons and holes to the first semiconductor region; and a second ohmic contact portion supplying the other of electrons and holes to the second semiconductor region; the method comprising the steps of: forming a plurality of semiconductor regions such that the first semiconductor region in contact with the first ohmic contact portion is made of AlGaN; and forming a first lower ohmic electrode in the first semiconductor region. A method for manufacturing an ultraviolet light-emitting semiconductor device is provided, comprising the step of forming a first upper electrode on a first lower ohmic electrode; wherein the first semiconductor region and the first lower ohmic electrode are heat-treated at a temperature of 700°C or higher so as to make ohmic contact with each other. Effects of the invention

[0017] This is described at the end of 'Specific details for implementing the invention'. Brief explanation of the drawing

[0018] FIG. 1 is a drawing showing an example of an ultraviolet light-emitting semiconductor device disclosed in U.S. Patent Publication No. US11,600,755. FIGS. 2 and FIGS. 3 are drawings showing an example of a semiconductor light-emitting device as disclosed in U.S. Patent Publication No. US10,158,047. FIG. 4 is a drawing showing another example of a semiconductor light-emitting device as disclosed in U.S. Patent Publication No. US10,158,047. FIGS. 5 to 7 are drawings showing an example of a semiconductor light-emitting device as disclosed in U.S. Patent Publication No. US8,247,823. FIGS. 8 and 9 are drawings showing test results according to the present disclosure, FIGS. 10 and FIGS. 11 are drawings showing another example of a conventional ultraviolet light-emitting semiconductor device. FIGS. 12 to 14 are drawings illustrating an example of an ultraviolet light-emitting semiconductor device according to the present disclosure. FIG. 15 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. FIG. 16 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. FIG. 17 is a drawing explaining the problems when forming a second insulating layer on a first insulating layer by a conventional method. FIG. 18 is a drawing showing an example of another method for manufacturing a semiconductor light-emitting device according to the present disclosure. FIG. 19 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure. FIG. 20 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure. FIG. 21 is a diagram illustrating the problems that occur when an actual semiconductor chip is bonded to an external substrate. FIG. 22 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure. FIG. 23 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure. FIG. 24 is a longitudinal section along the CC line of FIG. 10, FIG. 25 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. FIG. 26 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. FIG. 27 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. FIG. 28 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. Specific details for implementing the invention

[0019] The present disclosure will now be described in detail with reference to the accompanying drawings.

[0020] FIGS. 12 to 14 are drawings illustrating an example of an ultraviolet light-emitting semiconductor device according to the present disclosure, wherein the ultraviolet light-emitting semiconductor device comprises a substrate (10), a buffer region (20), a first semiconductor region (30), an active region (40), a second semiconductor region (50), a light-transmitting electrode (60), a first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2), a second ohmic electrode (74), an insulating layer (65), a first wiring electrode (81), a second wiring electrode (71-1, 71-2), a second insulating layer (66), a first pad electrode (80), and a second pad electrode (70).

[0021] As shown in FIG. 13 (a cross-sectional view along the AA line of FIG. 12), the first wiring electrode (81) is composed of a first wiring portion (81c) formed on the upper part of the first insulating layer (65), and a first electrical connection portion (81a-1, 81a-2, 81b-1, 81b-2) that is electrically connected to each of the first ohmic electrodes (85a-1, 85a-2, 85b-1, 85b-2) by penetrating the first insulating layer (65). In the presented example, the first ohmic electrodes (85a-1, 85a-2) are formed facing each other on the outer edge of the first semiconductor region (30) that is etched and exposed, and the first ohmic electrodes (81b-1, 81b-2) are formed facing each other within the first semiconductor region (30) that is etched and exposed, surrounded by the semiconductor region (40, 50), and the first ohmic electrodes (85a-1, 85a-2, 85b-1, 85b-2) have the form of branch electrodes. The first wiring electrode (81) and the first pad electrode (80) are electrically connected through a third electrical connection (80a) formed through the second insulating layer (66) as part of the first pad electrode (80).

[0022] As shown in FIG. 14 (a cross-sectional view along the BB line of FIG. 12), the second wiring electrode (71-1) is composed of a second wiring portion (71-1c) formed on the upper part of the first insulating layer (65) and a second electrical connection portion (71-1a) that is electrically connected through the second ohmic electrode (74) and the first insulating layer (65). In the example presented, the second ohmic electrode (74) is preferably formed over the entire front or nearly the entire front of the second semiconductor region (50) to the transparent electrode (60), and the second wiring electrode (71-1) and the second pad electrode (70) are electrically connected through a fourth electrical connection (70a) formed through the second insulating layer (66) as part of the second pad electrode (70). Although the second wiring section (71-1c) is depicted as a circular island shape, there are no particular restrictions on its number or shape as long as it is not electrically connected to the first wiring section (81c) and is stably electrically connected to the fourth electrical connection (70a). The second wiring electrode (71-2) is also formed in the same way as the second wiring electrode (71-1).

[0023] According to the presented example, ① a first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2) on the first semiconductor region (30) has a shape or size (e.g., branch electrode shape) greater than the size required for electrical connection with the first electrical connection part (81a-1, 81a-2, 81b-1, 81b-2) (e.g., circular island shape (refer to the second wiring electrode (71-1) in FIG. 12)) for sufficient current supply, ② irregularities occur on the first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2) during a heat treatment process at a high temperature (700°C or higher, or 900°C or higher in cases where the Al content is high) for ohmic contact between the first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2) and the first semiconductor region (30), and ③ a plurality of first ohmic Even in the case where a number of abrupt step surfaces occur during the process of exposing the first semiconductor region (30) to form electrodes (85a-1, 85a-2, 85b-1, 85b-2), and a number of defects such as cracks occur in the first insulating layer (65) formed thereon, unlike the example shown in FIG. 4, when viewing the first pad electrode (70) and the second pad electrode (80) from above, the first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2) is not placed between the first pad electrode (70) and the second pad electrode (80) (preferably so that the first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2) is covered by the first pad electrode (70) and the second pad electrode (80), so that the first pad electrode (70) and the second pad electrode (80) can be formed between the first pad electrode (70) and the second pad electrode (80). It is possible to prevent metal, moisture, etc. from penetrating through defects such as cracks during the bonding process with external components and thereafter.Meanwhile, a first wiring electrode (81) is formed on a first insulating layer (65) for electrical connection between the first ohmic electrode (85a-2, 85b-2) placed below the second pad electrode (70) and the first pad electrode (80), and the first wiring portion (81c) supplies current to the first ohmic electrode (85a-2, 85b-2) by passing from below the first pad electrode (80) to below the second pad electrode (70), and generally, high-temperature heat treatment of 700°C or higher is not required for the first wiring electrode (81). A second insulating layer (66) is formed on the first wiring electrode (81), and the first wiring electrode (81) is electrically insulated from the first pad electrode (80) and the second pad electrode (70).

[0024] FIG. 15 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure, wherein a first ohmic electrode (85a-1, 85a-2) is formed across three sides.

[0025] FIG. 16 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure, in which the first ohmic electrode (85b-2) is formed in a cross shape. In addition, various shapes of each of the first ohmic electrodes (85a-1, 85a-2, 85b-1, 85b-2) and combinations thereof are possible, and it is obvious that some parts may be omitted or added.

[0026] The substrate (10) is generally a growth substrate (e.g., a sapphire substrate), and the growth substrate (e.g., a Si substrate) may be removed and a newly attached transparent substrate may be used, and the substrate (10) may be removed or omitted.

[0027] The buffer region (20) may be composed of a single layer or multiple layers including (Al)GaN.

[0028] The first semiconductor region (30) includes n-type AlGaN and can be composed of multiple layers.

[0029] The active region (40) can be made of (Al)(IN)GaN / AlGaN multi-well structures (MQWs).

[0030] The second semiconductor region includes p-type AlGaN and can be composed of multiple layers.

[0031] The first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2) may be composed of a combination of multiple metals, such as Ti / Al / Ti / Au or Cr / Al / Ni / Au. One or more first ohmic electrodes (85a-1, 85a-2, 85b-1, 85b-2) may be formed under each of the first pad electrode (80) and the second wiring electrode (70).

[0032] The second ohmic electrode (74) may be configured in the same way as the first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2), but when functioning as a reflective film, it may be made of a combination of multiple metals such as Al / Ni / Au.

[0033] The transparent electrode (60) may be made of a TCO such as ITO, and may be omitted when the second ohmic electrode (74) functions as a reflective film.

[0034] The insulating layer (65) and the second insulating layer (66) are SiO2, Si x N y It can be composed of a single layer or multiple layers of dielectric materials such as TiO2, Al2O3, and, of course, may include reflective films such as ODR or DBR.

[0035] The first wiring electrode (81) and the second wiring electrode (71-1, 71-2) may be made of a combination of multiple metals such as Cr / Al / Ni / Au. The second wiring electrode (71-1, 71-2) may be formed as one or more.

[0036] The first pad electrode (80) and the second pad electrode (70) may be made of a combination of multiple metals such as Cr / Ni / Al / Au. Additionally, solder metals such as AuSn, SnAgCu, CuSn, NiSn, etc. may be added.

[0037] Returning to Fig. 11, when forming the second insulating layer (65) shown in Figs. 12 to 14 while a crack (CR) is formed in the first insulating layer (65), if the PECVD method, LPCVD method, or PVD method, which are generally used when forming the first insulating layer (65) and the second insulating layer (66), are used, even if the second insulating layer (66) is formed on the first insulating layer (65) which has defects such as a crack (CR), as shown in Fig. 17, it is not formed uniformly on the defects such as the crack (CR) or the gap is not filled, and a void (V) is formed.

[0038] FIG. 18 is a drawing illustrating another example of a method for manufacturing a semiconductor light-emitting device according to the present disclosure, illustrating a process of covering defects such as cracks (CR) through a recovery insulating layer (67) formed by an insulating layer forming method according to the present disclosure (ALD (Atomic Layer Deposition) method, iCVD (initiated CVD) method). As shown, compared to the PECVD method, LPCVD method, and PVD method, the Step Coverager is superior, and even when filling gaps, no voids are formed or very fine voids (MV) are formed.

[0039] ALD is a deposition method that builds up thin films layer by layer at the atomic layer level through chemical adsorption between a reaction gas and the wafer substrate surface. Typically, two precursors are sequentially injected without overlapping to induce a chemical reaction. The thin films grown in this way include Al2O3, HfO2, ZrO2, Ta2O5, La2O3, SiO2, and SiN xCompared to general CVD processes, it generates fewer particles during the process, offers excellent step coverage and gap filling, provides excellent uniformity over large areas, and enables processing even at low temperatures (<400℃); however, productivity is very low due to the low deposition rate. Therefore, since it is not suitable for growing thick films, a thickness of 200 nm or less is suitable, and preferably, it is used at a thickness of 100 nm or more.

[0040] iCVD is a process that deposits a polymer thin film on the surface of a substrate by vaporizing an initiator and a monomer to facilitate a polymer reaction in the gas phase. When the initiator decomposes due to a high-temperature filament or plasma to form radicals, these radicals activate the monomers to initiate a chain polymerization reaction. Peroxides, such as tert-butyl peroxide (TBPO), are primarily used as initiators. Monomers that can be used include hydroxyethylmethacrylate (HEMA), perfluoromoeotohydroxyacryyllase (PPFFMMAA), various diacrylate series, and fluoropolymer series such as PTFE, but there are no restrictions on the materials used. Polymer materials formed by this method possess excellent insulation properties and exhibit superior step coverage and gap filling characteristics, similar to those of ALD.

[0041] FIG. 19 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure, wherein a recovery insulating layer (67a) is added on a first insulating layer (65) formed by the ALD method and / or iCVD method described in FIG. 18 in the semiconductor light-emitting device presented in FIG. 11. Additionally, a recovery insulating layer (67b) may be formed on a second insulating layer (66), and it is also possible to form a recovery insulating layer (67c) after forming a first pad electrode (80) and a second pad electrode (70). After forming the recovery insulating layer (67a) on the first insulating layer (65), a via hole process for electrical connection is performed, and after forming the recovery insulating layer (67b) on the second insulating layer (66), a via hole process for electrical connection is performed, and after forming the recovery insulating layer (67c), a process of exposing the first pad electrode (80) and the second pad electrode (70) is performed. The process of introducing a recovery insulating layer (67a, 67b, 67c) can be applied to various semiconductor light-emitting devices, not only when the semiconductor light-emitting device is an ultraviolet light-emitting device, but also when it emits light such as blue or green.

[0042] FIG. 20 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure, in which a semiconductor light-emitting device in the form of a package is presented. For convenience of explanation, the semiconductor light-emitting device in the form of a semiconductor chip (hereinafter referred to as "semiconductor chip") presented in FIG. 19 has been simplified, and the semiconductor chip (A) is attached to an external substrate (B; e.g., a package substrate) having electrode pads (B1, B2). As shown in FIG. 21, even if an insulating layer (65, 66) is formed on the semiconductor chip (A), problems may occur in subsequent processes such as the insulating layer (65, 66) being destroyed (IF) or solder penetrating (SM). These problems are caused by Eject Pin Damage due to Die Pick & Place, destruction (IF) of the insulating layer (65, 66) at the boundary due to stress in contact with the pad electrode (70, 80) due to Reflow, and solder migration (SM) caused by the destruction (IF) of the insulating layer (65, 66). In addition, it is necessary to protect the device from external chemical components, moisture, and humidity. To overcome this problem, as illustrated, the semiconductor chip (A) is presented in a form having a recovery insulating layer (67c), and preferably, a recovery insulating layer (67d) is formed on the upper surface of the external substrate (B) while exposing the electrode pads (B1, B2). Even after the semiconductor chip (A) is bonded to the external substrate (B), a recovery insulating layer (67e) may be formed on at least the semiconductor chip (A) as needed, over the entire recovery insulating layer (67d), and the recovery insulating layers (67c, 67d) may be omitted. In addition, when an encapsulant (90; e.g., epoxy, silicon, fluoride resin) is provided, a recovery insulating layer (67f) may be formed to cover the upper surface of the encapsulant (90) and the point where the encapsulant (90) meets the recovery insulating layer (67d) or the upper surface of the external substrate (B).By providing at least one, preferably both, recovery insulating layer (67c) and recovery insulating layer (67e), it is possible to prevent the solder (S) used for bonding the pad electrodes (70, 80) and electrode pads (B1, B2) from penetrating into the semiconductor chip (A). Additionally, by forming the recovery insulating layer (67d) before bonding, instead of covering the upper surface of the external substrate (B) after the semiconductor chip (A) and the external substrate (B) are bonded with the recovery insulating layer (67f), insulation, moisture protection, and prevention of foreign substance penetration between the electrode pad (B1) and the electrode pad (B2) can be more reliably achieved. Although the process of manufacturing the semiconductor chip can be carried out at a temperature of 250°C or higher, high-temperature processes in subsequent processes are not suitable as they may affect the solder (S), encapsulating agent (90), etc. In the case of the general CVD method, the process temperature must be 250°C or higher to form a stable structure, and in the case of the PVD method, the deposition temperature is relatively low, resulting in poor adhesion or the quality of the insulating layer, making it unsuitable for use as an insulating or protective layer. According to the present disclosure, when using the ALD method or the iCVD method, high-quality thin films can be obtained at temperatures lower than 250°C, and in the case of iCVD, high-quality thin films can even be obtained at room temperature. For example, the following can be used as encapsulants.

[0043] FIG. 22 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure, wherein a frame (91) and a cover glass (92) are provided instead of an encapsulating agent (90), and is mainly used in a package of an ultraviolet light-emitting semiconductor chip (A). Similar to FIG. 20, a recovery insulating layer (67f) is formed to cover the frame (91) and the cover glass (92), thereby blocking the ingress of moisture into the package. The external substrate (B) is not limited to a package substrate and can be an interposer, a cell of a display, etc.

[0044] FIG. 23 is a drawing showing another example of a semiconductor light-emitting device according to the present disclosure, illustrating an example in which a recovery insulating layer (67g) is formed in the internal space of a package defined by a frame (91) prior to forming a cover glass (92). The semiconductor chip (A) and the internal space are covered by the recovery insulating layer (67g), and the recovery insulating layer (67d) and the recovery insulating layer (67e) are not formed, thereby having the effect of forming them at once.

[0045] FIG. 24 is a cross-sectional view along the CC line of FIG. 10, and the size has been arbitrarily adjusted for convenience of explanation. As described above, in an ultraviolet semiconductor light-emitting device, the first semiconductor region (30) in contact with the first ohmic electrode (85a, 85b) is made of AlGaN, and the first ohmic electrode (85a, 85b), which is made of a combination of Cr, Ti, V, Ni, Al, Au, etc., undergoes high-temperature heat treatment to improve ohmic contact after being deposited on the first semiconductor region (30). During this heat treatment process, an alloy that improves ohmic characteristics, such as TiN, AlN, and Al3Ti, is formed between the material constituting the first semiconductor region (30) (AlGaN) and the material constituting the first ohmic electrode (85a, 85b) (e.g., a combination of Cr, Ti, V, Ni, Al, Au, etc.), thereby forming ohmic contact, but a component that degrades ohmic characteristics, such as Au-Al, is also formed. As the thickness of the first ohmic electrode (85a, 85b) increases, the adverse effect of the component that degrades ohmic characteristics also increases. Considering this, it is common practice to design the thickness of the first ohmic electrode (85a, 85b) to be 1 μm or less. However, this constraint acts as a cause for increasing the current diffusion resistance during high-current operation. The description of unexplained identical reference numerals (10, 20, 65, 80) is omitted.

[0046] FIG. 25 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure, in which an example of the present disclosure is applied to the device presented in FIG. 24. As shown, a first upper electrode (85-1a, 85-1b) is formed on each of the first ohmic electrodes (85a, 85b; hereinafter referred to as the 'first lower ohmic electrode') in electrical and physical contact with the first semiconductor region (30) and the first lower ohmic electrode (85a, 85b). In addition, an insulating layer (68; e.g., SiO2)) is provided to insulate the first upper electrode (85-1a, 85-1b) and the semiconductor region (40, 50) from each other while exposing the first semiconductor region (30) and the first lower ohmic electrode (85a, 85b). Through this configuration, the thickness of the first lower ohmic electrode (85a, 85b) is constrained to suppress components that inhibit ohmic characteristics within the first lower ohmic electrode (85a, 85b) after heat treatment, while preventing problems in the current diffusion process across the entire device even when a high current is applied through the first upper electrode (85-1a, 85-1b). It is also preferable for the first upper electrode (85-1a, 85-1b) to be in contact with the first semiconductor region (30). In the case where the device is a flip chip, preferably, as illustrated, the first upper electrode (85-1a, 85-1b) is formed to span over the semiconductor region (30, 40, 50), thereby improving the light reflection function to the growth substrate (10). The width or thickness may vary depending on the high current application specifications required for the device. In this example, the first lower ohmic electrodes (85a, 85b) are formed in the form of branch electrodes on the inside and outside of the device, but from the perspective of the technical concept of the present disclosure presented in FIG. 25, the first lower ohmic electrodes (85a, 85b) can be formed in island shapes such as circles or squares, and there are no restrictions on the number thereof. The description of unexplained identical reference numerals (20, 60, 65, 70, 74, 80, 81b) is omitted.

[0047] FIG. 26 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. An example of the present disclosure is applied to a cross-sectional view along the DD line of FIG. 10, and the size is arbitrarily adjusted for convenience of explaining the drawing. The second ohmic electrode (74) is configured to be divided into a second lower ohmic electrode (74) and a second upper electrode (74-1), similar to FIG. 25, and is electrically connected to the second pad electrode (70) through a second electrical connection (71a). The description of unexplained identical reference numerals (40, 50, 60, 65, 68, 85a, 85-1a) is omitted.

[0048] The first lower ohmic electrode (85a, 85b) and the first upper electrode (85-1a, 85-1b) and the second lower ohmic electrode (74) and the second upper electrode (74-1) applied in FIGS. 25 and 26 can be applied to the device shown in FIGS. 12 to 19, and can be applied to any structure of an ultraviolet light-emitting semiconductor device having the pointed-out problem.

[0049] Hereinafter, an example of a method for manufacturing the device shown in FIG. 25 is described. First, a first lower ohmic electrode (85a, 85b; thickness of 1 μm or less) is formed, and then a heat treatment (e.g., 700°C or higher) is performed to form an ohmic contact. Next, an insulating layer (68) is formed in the shape shown. Next, a first upper electrode (85-1a, 85-1b) is formed (thickness of 1 μm to 2 μm). It is also possible to form the insulating layer (68) before the first lower ohmic electrode (85a, 85b). In the case of the example shown in FIG. 26, it can be formed in the same way, and when both the first upper electrode (85-1a, 85-1b) and the second upper electrode (74-1) are provided, the insulating layer (68) can be used in common, and the first upper electrode (85-1a, 85-1b) and the second upper electrode (74-1) can be formed together in a single process. The first lower ohmic electrode (85a, 85b) can be made of a combination of Al, Ti, Ni, V, Cr, Au, etc., and the heat treatment temperature is suitable to be 700°C or higher, and the second lower ohmic electrode (74) can be made of a combination of Al, Ni, Au, Rh, Ti, Au, Pt, etc., and the first upper electrode (85-1a, 85-1b) and the second upper electrode (74-1) can be formed without heat treatment with a thickness of about 1 to 2 μm using a combination of Cr, Al, Ni, Au, Pt, Ti, etc.

[0050] FIG. 27 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure. Unlike the example shown in FIG. 25, the growth substrate (10) is exposed (the chip is isolated), and the first upper electrode (85-1a) extends over the exposed growth substrate (10) to increase the contact area with the first semiconductor region (30) while ensuring more light reflection toward the growth substrate (10). The first upper electrode (85-1a) is covered and protected by an insulating layer (65).

[0051] FIG. 28 is a drawing showing another example of an ultraviolet light-emitting semiconductor device according to the present disclosure, in addition to the example presented in FIG. 27, an insulating layer (68) is also formed between the growth substrate (10) to be exposed and the first upper electrode (85-1a) extended thereover.

[0052] Various embodiments of the present disclosure will be described below.

[0053] (1) A method for manufacturing an ultraviolet light-emitting semiconductor device, comprising: forming a plurality of semiconductor regions including a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region that emits ultraviolet light through the recombination of electrons and holes; forming a plurality of first ohmic electrodes on the first semiconductor region and a second ohmic electrode on the second semiconductor region; wherein the method comprises heat treatment of 700°C or higher A step of forming a plurality of first ohmic electrodes and a plurality of second ohmic electrodes, forming a plurality of first ohmic electrodes in a first semiconductor region; a step of forming a first insulating layer on the plurality of first ohmic electrodes and a second ohmic electrode; a step of forming a first wiring electrode on the first insulating layer to be electrically connected to the plurality of first ohmic electrodes and a second wiring electrode to be electrically connected to the second ohmic electrode; a step of forming a second insulating layer on the first wiring electrode and the second wiring electrode; A method for manufacturing an ultraviolet light-emitting semiconductor device, comprising the step of forming a first pad electrode to be electrically connected to a first wiring electrode and a second pad electrode to be electrically connected to a second wiring electrode on a second insulating layer; wherein one of a plurality of first ohmic electrodes is located below the first pad electrode and another of the plurality of first ohmic electrodes is located below the second pad electrode, and the plurality of first ohmic electrodes are not exposed through the space between the first pad electrode and the second pad electrode when viewed from above, and one of the plurality of first ohmic electrodes and another of the plurality of first ohmic electrodes are electrically connected through a first wiring portion of a first wiring electrode located above the first insulating layer and below the second insulating layer.

[0054] (2) A method for manufacturing an ultraviolet light-emitting semiconductor device in which one of the plurality of first ohmic electrodes and the other of the plurality of first ohmic electrodes are each located on opposite sides of the ultraviolet light-emitting semiconductor device.

[0055] (3) A method for manufacturing an ultraviolet light-emitting semiconductor device in which one of the plurality of first ohmic electrodes and the other of the plurality of first ohmic electrodes are each surrounded by an active region and a second semiconductor region.

[0056] (4) A method for manufacturing an ultraviolet light-emitting semiconductor device in which at least one of the plurality of first ohmic electrodes is a branch electrode.

[0057] (5) A method for manufacturing a semiconductor light-emitting device, comprising: forming a plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region that emits light through the recombination of electrons and holes; forming a first pad electrode electrically connected to the first semiconductor region and a second pad electrode electrically connected to the second semiconductor region; and forming at least one insulating layer between the plurality of semiconductor regions and the first and second pad electrodes; and further comprising, prior to forming the first and second pad electrodes, forming a recovery insulating layer at least once by applying one of the ALD method and the iCVD method to the at least one insulating layer.

[0058] (6) A method for manufacturing a semiconductor light-emitting device, wherein at least one insulating layer comprises a first insulating layer in contact with a plurality of semiconductor regions, and a first recovery insulating layer is formed on the first insulating layer.

[0059] (7) A method for manufacturing a semiconductor light-emitting device, wherein at least one insulating layer comprises a first insulating layer in contact with a plurality of semiconductor regions and a second insulating layer in contact with the first insulating layer, and a second recovery insulating layer is formed on the second insulating layer.

[0060] (8) A method for manufacturing a semiconductor light-emitting device in which a third recovery insulating layer is formed while exposing a first pad electrode and a second pad electrode on at least one insulating layer.

[0061] (9) A method for manufacturing a semiconductor light-emitting device, further comprising the step of forming a plurality of first ohmic electrodes and a second ohmic electrode on a second semiconductor region by heat treatment of 700°C or higher on a first semiconductor region; wherein the active region emits ultraviolet light, and the plurality of first ohmic electrodes are electrically connected to a first pad electrode and the second ohmic electrode is electrically connected to a second pad electrode, and at least one insulating layer includes a first insulating layer in contact with the plurality of semiconductor regions and a second insulating layer in contact with the first insulating layer, and one of the plurality of first ohmic electrodes is located below the first pad electrode and another of the plurality of first ohmic electrodes is located below the second pad electrode, and the plurality of first ohmic electrodes are arranged so as not to be exposed through the space between the first pad electrode and the second pad electrode when viewed from above.

[0062] (10) A method for manufacturing a semiconductor light-emitting device, comprising: a plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region to emit light through the recombination of electrons and holes; a first pad electrode electrically connected to the first semiconductor region; a second pad electrode electrically connected to the second semiconductor region; and a semiconductor chip comprising at least one insulating layer provided between the plurality of semiconductor regions and the first and second pad electrodes; and a step of preparing an external substrate having a first electrode pad and a second electrode pad. A method for manufacturing a semiconductor light-emitting device, comprising: a step of attaching a semiconductor chip to an external substrate such that a first pad electrode is bonded to a first electrode pad and a second pad electrode is bonded to a second electrode pad; and further comprising, in the step of preparing the semiconductor chip, a step of forming a recovery insulating layer at least once by applying one of the ALD method and the iCVD method to at least one insulating layer, wherein a recovery insulating layer is formed at least once by applying one of the ALD method and the iCVD method to an external substrate to which the semiconductor chip is attached.

[0063] (11) A method for manufacturing a semiconductor light-emitting device, wherein, in the step of forming a recovery insulating layer, the first recovery insulating layer is formed on the first pad electrode and the second pad electrode while exposing the first pad electrode and the second pad electrode.

[0064] (12) A method for manufacturing a semiconductor light-emitting device in which, prior to the attachment step, a second recovery insulating layer is formed while exposing the first electrode pad and the second electrode pad to an external substrate.

[0065] (13) A method for manufacturing a semiconductor light-emitting device, wherein, prior to the attachment step, a second recovery insulating layer is formed while exposing a first electrode pad and a second electrode pad to an external substrate, and the second recovery insulating layer faces the first recovery insulating layer between the first electrode pad and the second electrode pad.

[0066] (14) A method for manufacturing a semiconductor light-emitting device in which, after the attachment step, a third recovery insulating layer is formed to cover the semiconductor chip and the external substrate.

[0067] (15) A method for manufacturing a semiconductor light-emitting device in which, after the attachment step, a third recovery insulating layer is formed to cover the semiconductor chip and the external substrate, and the third recovery insulating layer covers the second recovery insulating layer.

[0068] (16) A method for manufacturing a semiconductor light-emitting device, further comprising the step of forming an encapsulant to cover the semiconductor chip and the external substrate after the attachment step, wherein a fourth recovery insulating layer is formed on the encapsulant.

[0069] (17) A method for manufacturing a semiconductor light-emitting device, further comprising the step of forming a frame and a cover glass on an external substrate after the attachment step, wherein a fourth recovery insulating layer is formed to cover the frame and the cover glass.

[0070] (18) A step of forming a frame and a cover glass on an external substrate after the attachment step; further comprising, and a fifth recovery insulating layer formed before forming the cover glass, a method for manufacturing a semiconductor light-emitting device.

[0071] (19) A semiconductor device for ultraviolet light emitting light, comprising: a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region to emit ultraviolet light through the recombination of electrons and holes; a first ohmic contact portion that supplies one of electrons and holes to the first semiconductor region; and a second ohmic contact portion that supplies the other of electrons and holes to the second semiconductor region; wherein the first semiconductor region in contact with the first ohmic contact portion is made of AlGaN, and the first ohmic contact portion comprises a first lower ohmic electrode that is in ohmic contact with the first semiconductor region; and a first upper electrode formed on the first lower ohmic electrode while in contact with the first lower ohmic electrode and the first semiconductor region; and wherein the device comprises an insulating layer that electrically insulates the first upper electrode, the active region, and the second semiconductor region.

[0072] (20) A semiconductor device emitting ultraviolet light, having a first lower ohmic electrode thickness of 1 μm or less.

[0073] (21) A growth substrate on which a plurality of semiconductor regions are grown; further comprising, and a first upper electrode extending over the growth substrate in which a plurality of semiconductor regions are removed and exposed.

[0074] (22) A first upper electrode extends over an insulating layer and over a second semiconductor region, forming an ultraviolet light-emitting semiconductor device.

[0075] (23) A first lower ohmic electrode comprises a material that inhibits ohmic contact by combining with Al in the first semiconductor region, in an ultraviolet light-emitting semiconductor device.

[0076] (24) A second ohmic contact portion comprises a second lower ohmic electrode that is in ohmic contact with the second semiconductor region side; and a second upper electrode formed on the second lower ohmic electrode while in contact with the second lower ohmic electrode and the second semiconductor region side. Here, the expression 'second semiconductor region side' is used because the second lower ohmic electrode (74) can be in contact with the light-transmitting electrode (60) rather than the second semiconductor region (50) when the light-transmitting electrode (60) is provided.

[0077] (25) A plurality of semiconductor regions having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region to emit ultraviolet light through the recombination of electrons and holes; a first ohmic contact portion having a first lower ohmic electrode and a first upper electrode to supply one of electrons and holes to the first semiconductor region; and a second ohmic contact portion supplying the other of electrons and holes to the second semiconductor region; wherein the method comprises the steps of: forming a plurality of semiconductor regions such that the first semiconductor region in contact with the first ohmic contact portion is made of AlGaN; forming a first lower ohmic electrode in the first semiconductor region; and forming a first upper electrode on the first lower ohmic electrode; wherein the first semiconductor region and the first lower ohmic electrode are heat-treated at a temperature of 700°C or higher to make ohmic contact with each other.

[0078] (26) A method for manufacturing an ultraviolet light-emitting semiconductor device, wherein the thickness of the first lower ohmic electrode is formed to be 1 μm or less in the step of forming the first lower ohmic electrode.

[0079] (27) A method for manufacturing an ultraviolet light-emitting semiconductor device, further comprising the step of forming an insulating layer that insulates the first upper electrode from the active region and the second semiconductor region, wherein the first upper electrode extends over the second semiconductor region through the insulating layer.

[0080] (28) A method for manufacturing an ultraviolet light-emitting semiconductor device, wherein the ultraviolet light-emitting semiconductor device further comprises a growth substrate on which a plurality of semiconductor regions are grown; and, prior to the step of forming a first upper electrode, a step of removing a portion of the semiconductor region of the abdomen to expose the growth substrate; wherein, in the step of forming the first upper electrode, the first upper electrode extends over the exposed growth substrate.

[0081] According to the method for manufacturing a single ultraviolet light-emitting semiconductor device according to the present disclosure, it is possible to prevent metal, moisture, etc. from penetrating through defects in the device and causing problems with the reliability of the device.

[0082] According to the method for manufacturing a semiconductor light-emitting device according to the present disclosure, the reliability of the device can be improved by applying the ALD method and / or the iCLD method.

[0083] According to one ultraviolet light-emitting semiconductor device and a method for manufacturing the same according to the present disclosure, current diffusion during high-current operation can be improved. Explanation of the symbols

[0084] Substrate (10), buffer region (20), first semiconductor region (30), active region (40), second semiconductor region (50), transparent electrode (60), first ohmic electrode (85a-1, 85a-2, 85b-1, 85b-2), second ohmic electrode (74), insulating layer (65), first wiring electrode (81), second wiring electrode (71-1, 71-2), second insulating layer (66), first pad electrode (80), second pad electrode (70)

Claims

Claim 1 delete Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A method for manufacturing an ultraviolet emitting semiconductor device comprising: a plurality of semiconductor regions each having a first semiconductor region having a first conductivity, a second semiconductor region having a second conductivity different from the first conductivity, and an active region interposed between the first semiconductor region and the second semiconductor region that emits ultraviolet light through the recombination of electrons and holes; a first ohmic contact portion having a first lower ohmic electrode and a first upper electrode to supply one of electrons and holes to the first semiconductor region; and a second ohmic contact portion supplying the other of electrons and holes to the second semiconductor region; the method comprising the steps of: forming a plurality of semiconductor regions such that the first semiconductor region in contact with the first ohmic contact portion is made of AlGaN; and forming a first lower ohmic electrode in the first semiconductor region. A method for manufacturing an ultraviolet light-emitting semiconductor device, comprising: a step of forming a first upper electrode on a first lower ohmic electrode; wherein the first semiconductor region and the first lower ohmic electrode are heat-treated at a temperature of 700°C or higher so as to be in ohmic contact with each other; further comprising a step of forming an insulating layer between a plurality of semiconductor regions and the first upper electrode; wherein the first upper electrode extends over a second semiconductor region through the insulating layer and forms a first pad electrode electrically connected to the first upper electrode, wherein an additional insulating layer is formed between the first pad electrode and the first upper electrode, and an electrical connection portion is formed penetrating the additional insulating layer to electrically connect the first upper electrode and the first pad electrode; and wherein the first upper electrode covers the first lower ohmic electrode without an opening on top of the first lower ohmic electrode. Claim 8 A method for manufacturing an ultraviolet light-emitting semiconductor device according to claim 7, wherein, in the step of forming a first lower ohmic electrode, the thickness of the first lower ohmic electrode is formed to be 1 μm or less. Claim 9 A method for manufacturing an ultraviolet light-emitting semiconductor device according to claim 8, wherein the first lower ohmic electrode comprises Au, and an Al-Au alloy is formed between the first semiconductor region and the first lower ohmic electrode during the heat treatment process. Claim 10 A method for manufacturing an ultraviolet light-emitting semiconductor device according to claim 7, wherein the ultraviolet light-emitting semiconductor device further comprises a growth substrate on which a plurality of semiconductor regions are grown; and, prior to the step of forming a first upper electrode, further comprises the step of removing a portion of the plurality of semiconductor regions to expose the growth substrate; wherein, in the step of forming the first upper electrode, the first upper electrode extends over the exposed growth substrate.

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