Semiconductor device and semiconductor device package including the same

Abstract

An embodiment of the present application discloses a semiconductor device and a semiconductor device package including the same, wherein the semiconductor device includes: a light emitting structure, the light emitting structure includes a first conductive semiconductor layer, a second conductive semiconductor layer and an active layer, the active layer is arranged between the first conductive semiconductor layer and the second conductive semiconductor layer; the second conductive semiconductor layer has a ratio of a second shortest distance W2 to a first shortest distance W1 in a range of 1:1.25 to 1:100, the second shortest distance W2 is a distance from a first surface to a second point, and the first shortest distance W1 is a distance from the first surface to a first point; the first surface is a surface of the second semiconductor layer away from the active layer; the first point is a point where the aluminum composition of the second conductive semiconductor layer is the same as the aluminum composition of a well layer of the active layer closest to the second conductive semiconductor layer; and the second point is a point where the second conductive semiconductor layer has a dopant composition that is the same as the aluminum composition.

Description

[0001] This application is a divisional application of an invention patent application with an international application date of September 13, 2017, an international application number of PCT / KR2017 / 010065, an application number of 201780056302.2 entering the Chinese national phase, and an invention name of “Semiconductor device and semiconductor device package including the semiconductor device”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of Korean Patent Application No. 10-2016-0118243 filed in Korea on September 13, 2016, Korean Patent Application No. 10-2016-0140466 filed in Korea on October 26, 2016, and Korean Patent Application No. 10-2017-0115836 filed in Korea on September 11, 2017, which are hereby incorporated by reference in their entirety. Technical Field

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

[0005] Semiconductor devices including compounds such as GaN and AlGaN have many advantages such as adjustable wide bandgap energy and thus can be widely 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 light of various colors, such as red, green, blue and ultraviolet, and can also achieve efficient 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 speed, safety and environmental protection.

[0007] In addition, when a light receiving device such as an optical detector or a solar cell is manufactured using III-V or II-VI compound semiconductors, a photocurrent can be generated due to light absorption in various wavelength ranges due to the development of device materials. Thus, light in various wavelength ranges from gamma rays to radio wavelength ranges can be used. In addition, the light receiving device has the advantages of fast response time, safety, environmental protection, and easy adjustment of device materials, and can be easily used in power control, microwave circuits, or communication modules.

[0008] Therefore, semiconductor devices have been widely used in the following occasions: transmission modules of optical communication devices; LED backlights that replace cold cathode fluorescent lamps (CCFLs) used to form backlights of liquid crystal display (LCD) devices; white LED lamps that replace fluorescent lamps or incandescent lamps; vehicle headlights; traffic lights; and sensors for detecting gas or fire. In addition, semiconductor devices can also be widely used in high-frequency application circuits, other power control devices, and even communication modules.

[0009] In particular, light emitting devices that emit light in the ultraviolet wavelength range may be used for curing, medical treatment, and sterilization purposes due to their curing or sterilizing effects.

[0010] Recently, research on ultraviolet light emitting devices has been actively conducted, but ultraviolet light emitting devices are difficult to realize vertically and crystallinity is also reduced in a substrate separation process. Summary of the invention

[0011] Technical issues

[0012] The embodiment provides a vertical ultraviolet light emitting device.

[0013] Embodiments also provide a light emitting device with enhanced light output power.

[0014] The problems to be solved by the embodiments are not limited thereto, but include the following technical solutions and purposes of effects that can be understood through the embodiments.

[0015] Solution

[0016] A semiconductor device according to an embodiment of the present invention includes: a light emitting structure, the light emitting structure including a first conductive semiconductor layer, a second conductive semiconductor layer and an active layer, the active layer being disposed between the first conductive semiconductor layer and the second conductive semiconductor layer; a first electrode electrically connected to the first conductive semiconductor layer; and a second electrode electrically connected to the second conductive semiconductor layer. The second conductive semiconductor layer may include a first surface on which the second electrode is disposed. A ratio (W2:W1) of a second shortest distance W2 to a first shortest distance W1 of the second conductive semiconductor layer may be 1:1.25 to 1:100, the second shortest distance W2 being a distance from the first surface to a second point, and the first shortest distance W1 being a distance from the first surface to a first point. The first point may be a point at which the aluminum composition of the second conductive semiconductor layer is the same as the aluminum composition of the well layer of the active layer closest to the second conductive semiconductor layer. The second point may be a point at which the second conductive semiconductor layer has a dopant composition that is the same as the aluminum composition.

[0017] Advantageous Effects of the Invention

[0018] According to the embodiment, a vertical ultraviolet light emitting device may be manufactured.

[0019] It can also enhance the light output power.

[0020] Various advantageous advantages and effects of the present invention are not limited to the above description and can be easily understood by describing the embodiments of the present invention in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a conceptual view of a light emitting structure according to an embodiment of the present invention;

[0022] Figure 2 is a graph showing the aluminum composition of the light emitting structure according to an embodiment of the present invention;

[0023] Figure 3 is a secondary ion mass spectrometry (SIMS) graph of the light emitting structure according to the first embodiment of the present invention;

[0024] Figure 4 yes Figure 3 A partial enlarged view of

[0025] Figure 5 is a SIMS graph of a light emitting structure according to a second embodiment of the present invention;

[0026] Figure 6 yes Figure 5 A partial enlarged view of

[0027] Figure 7 is a SIMS graph of a light emitting structure according to a third embodiment of the present invention;

[0028] Figure 8 yes Figure 7 A partial enlarged view of

[0029] Fig. 9 is a conceptual view of a semiconductor device according to an embodiment of the present invention;

[0030] Fig.10 is a graph showing aluminum composition of a semiconductor structure according to an embodiment of the present invention;

[0031] Fig.11a and Fig.11b shows SIMS data of a semiconductor structure according to an embodiment of the present invention;

[0032] Fig.11c and Fig.11d shows SIMS data of a semiconductor structure according to another embodiment of the present invention;

[0033] Fig.12 It is shown Figures 11a to 11d A graph of the aluminum ion strength;

[0034] Fig.13a It is shown Fig.12 Figure 2. (a) is an enlarged view of SIMS data.

[0035] Fig.13b It is shown Fig.12 Part (b) of the graph is a graph of SIMS data converted to a linear scale;

[0036] Fig.14a is a conceptual view of a second conductive semiconductor layer according to an embodiment of the present invention;

[0037] Fig.14b shows AFM data obtained by measuring the surface of the second conductive semiconductor layer according to an embodiment of the present invention;

[0038] Fig.14c shows AFM data obtained by measuring the surface of a GaN thin film;

[0039] Fig.14d shows AFM data obtained by measuring the surface of a second conductive semiconductor layer grown at a high speed;

[0040] Fig.15 is a conceptual view of a semiconductor device according to an embodiment of the present invention;

[0041] Fig.16a and Fig.16b is a diagram showing a configuration in which light output power is enhanced as the number of grooves is changed;

[0042] Fig.17 yes Fig.15 An enlarged view of part A;

[0043] Fig.18 is a conceptual view of a semiconductor device according to another embodiment of the present invention;

[0044] Fig.19 yes Fig.18 Floor plan of

[0045] Fig. 20 is a conceptual view of a semiconductor device package according to an embodiment of the present invention;

[0046] Fig.21 is a plan view of a semiconductor device package according to an embodiment of the present invention;

[0047] Fig. 22 yes Fig.21 Variations of;

[0048] Fig.23 is a cross-sectional view of a semiconductor device package according to another embodiment of the present invention;

[0049] Fig.24 is a conceptual view of a light emitting structure according to an embodiment of the present invention;

[0050] Fig.25 is a graph showing the aluminum composition of the light emitting structure according to an embodiment of the present invention;

[0051] Fig.26 is a graph showing the aluminum composition of a light emitting structure according to another embodiment of the present invention;

[0052] Fig. 27 is a graph obtained by measuring the light efficiency of a semiconductor device including a conventional light emitting structure;

[0053] Fig.28 is a graph obtained by measuring the light efficiency of a light emitting structure according to another embodiment of the present invention;

[0054] Fig.29 is a graph showing the aluminum composition of a light emitting structure according to yet another embodiment of the present invention;

[0055] Fig.30 is a conceptual view of a light-emitting structure grown on a substrate;

[0056] Fig.31 is a diagram showing a process of separating a substrate;

[0057] Fig.32 is a diagram showing a process of etching a light emitting structure; and

[0058] Fig.33 2 is a diagram showing a manufactured semiconductor device. DETAILED DESCRIPTION

[0059] The following embodiments may be modified or combined with each other, and the scope of the present invention is not limited to these embodiments.

[0060] Details described in a specific embodiment may be understood as descriptions related to other embodiments, even if there is no such description in the other embodiments, unless otherwise stated or there is a contradiction.

[0061] For example, when features of element A are described in one specific embodiment and features of element B are described in another embodiment, embodiments combining element A and element B should be understood to fall within the scope of the present invention, even if not explicitly stated, unless otherwise specified or there is a contradiction.

[0062] When describing an embodiment, if an element is described as being located above or below another element, the two elements may be in direct contact with each other, or one or more other elements may be disposed between the two elements. In addition, the term "located above or below" as used herein may refer to an upward direction as well as a downward direction relative to an element.

[0063] Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings to be easily implemented by those skilled in the art.

[0064] The light emitting structure according to an embodiment of the present invention can output ultraviolet wavelength light. For example, the light emitting structure can output near ultraviolet wavelength light (UV-A), far ultraviolet wavelength light (UV-B), or deep ultraviolet wavelength light (UV-C). The wavelength range can be determined by the aluminum composition of the light emitting structure 120.

[0065] For example, the wavelength of near ultraviolet wavelength light (UV-A) may be 320nm to 420nm, the wavelength of far ultraviolet wavelength light (UV-B) may be 280nm to 320nm, and the wavelength of deep ultraviolet wavelength light (UV-C) may be 100nm to 280nm.

[0066] Figure 1 is a conceptual view of a light emitting structure according to an embodiment of the present invention; Figure 2 is a graph illustrating aluminum composition of a semiconductor structure according to an embodiment of the present invention.

[0067] See also Figure 1 The semiconductor device according to the embodiment includes a light emitting structure including a first conductive semiconductor layer 124 , a second conductive semiconductor layer 127 , and an active layer 126 , and the active layer 126 is disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127 .

[0068] 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. x1 Al y1 Ga 1-x1-y1 The first conductive semiconductor layer 124 may be made of one of a plurality of semiconductor materials (e.g., GaN, AlGaN, InGaN, InAlGaN, etc.) having a thickness of N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1). 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.

[0069] 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 low energy level and generate light having an ultraviolet wavelength.

[0070] The active layer 126 may have 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, but is not limited thereto.

[0071] 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 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 having a thickness of 0.0447 W / m2 or a thickness of 0.0247 W / m2. The second conductive semiconductor layer 127 may be made of a semiconductor material having a thickness of 0.0447 W / m2 or a thickness of 0.0547 W / m2. The second conductive semiconductor layer 127 may be made of a semiconductor material having a thickness of 0.0447 W / m2 or a thickness of 0.0547 W / m2.

[0072] The second conductive semiconductor layer 127 may include a 2-1 (second-prime) conductive semiconductor layer 127a, a 2-2 (second-second-primary) conductive semiconductor layer 127b, and a 2-3 (second-third-primary) conductive semiconductor layer 127c. The aluminum composition of the 2-1 conductive semiconductor layer 127a may be lower than that of the 2-2 conductive semiconductor layer 127b.

[0073] 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 electrons provided by the first conductive semiconductor layer 124 from flowing to the second conductive semiconductor layer 127, thereby increasing the possibility of recombination of electrons and holes in the active layer 126. The energy band gap of the electron blocking layer 129 may be higher than the energy band gap of the active layer 126 and / or the second conductive semiconductor layer 127.

[0074] The electron blocking layer 129 may be made of a material selected from the empirical formula In x1 Al y1 Ga 1-x1-y1The electron blocking layer 129 may be made of one of a plurality of semiconductor materials (e.g., AlGaN, InGaN, InAlGaN, etc.) having a thickness of N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1), but is not limited thereto. The first layer 129b containing a high aluminum content and the second layer 129a containing a low aluminum content may be alternately disposed in the electron blocking layer 129.

[0075] See also Figure 2 , the first conductive semiconductor layer 124, the barrier layer 126b, the well layer 126a, the 2-1 conductive semiconductor layer 127a, the 2-2 conductive semiconductor layer 127b, and the 2-3 conductive semiconductor layer 127c 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, the 2-2 conductive semiconductor layer 127b, and the 2-3 conductive semiconductor layer 127c may all be made of AlGaN. However, the present invention is not limited thereto.

[0076] The electron blocking layer 129 may have an aluminum composition of 50% to 90%. The blocking layer 129 may have a plurality of first blocking layers 129a having a higher aluminum composition and a plurality of second blocking layers 129b having a lower aluminum composition, and the first blocking layers 129a and the second blocking layers 129b are alternately arranged in the blocking layer 129. When the aluminum composition of the blocking layer 129 is less than 50%, the energy barrier for blocking electrons may not be high enough, and the blocking layer 129 may absorb light emitted from the active layer 126. When the aluminum composition of the blocking layer 129 is greater than 90%, the electrical characteristics of the semiconductor device may be reduced.

[0077] The electron blocking layer 129 may include a 1-1 portion 129-1 and a 1-2 portion 129-2. The aluminum component contained in the 1-1 portion 129-1 may increase toward the blocking layer 129. The 1-1 portion 129-1 may have an aluminum component of 80% to 100%. That is, the 1-1 portion 129-1 may be made of AlGaN or AlN. Alternatively, the 1-1 portion 129-1 may be a superlattice layer in which AlGaN and AlN are alternately arranged.

[0078] The thickness of the 1-1 portion 129-1 may be about 0.1 nm to about 4 nm. When the thickness of the 1-1 portion 129-1 is less than 0.1 nm, electron movement may not be effectively blocked. When the thickness of the 1-1 portion 129-1 is greater than 4 nm, the efficiency of hole injection into the active layer 126 may be reduced.

[0079] The 1-2 portion 129 - 2 may include an undoped portion. The 1-2 portion 129 - 2 may function to prevent dopants from diffusing from the second conductive semiconductor layer 127 to the active layer 126 .

[0080] The thickness of the 2-2 conductive semiconductor layer 127b may be greater than 10nm and less than 200nm. For example, the thickness of the 2-2 conductive semiconductor layer 127b may be equal to 25nm. When the thickness of the 2-2 conductive semiconductor layer 127b is less than 10nm, the resistance increases in the horizontal direction, thereby possibly reducing the current injection efficiency. When the thickness of the 2-2 conductive semiconductor layer 127b is greater than 200nm, the resistance increases in the vertical direction, thereby possibly reducing the current injection efficiency.

[0081] The aluminum composition of the 2-2 conductive semiconductor layer 127b may be higher than the aluminum composition of the well layer 126a. In order to generate ultraviolet light, the well layer 126a may have an aluminum composition of about 30% to about 70%. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is lower than the aluminum composition of the well layer 126a, the 2-2 conductive semiconductor layer 127b absorbs light, and thus it is possible to reduce the light extraction efficiency. However, in order to prevent the crystallinity of the light emitting structure from deteriorating, the present invention is not limited thereto. For example, in some parts, the aluminum composition of the 2-2 conductive semiconductor layer 127b may be lower than the aluminum composition of the well layer 126a.

[0082] The 2-2 conductive semiconductor layer 127b may have an aluminum composition greater than 40% and less than 80%. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is less than 40%, light may be absorbed. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is greater than 80%, current injection efficiency may decrease. For example, when the aluminum composition of the well layer 126a is 30%, the aluminum composition of the 2-2 conductive semiconductor layer 127b may be 40%.

[0083] The aluminum composition of the 2-1 conductive semiconductor layer 127a may be lower than that of the well layer 126a. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is higher than that of the well layer 126a, the 2-1 conductive semiconductor layer 127a cannot make sufficient ohmic contact with the p-ohmic electrode because the resistance between the 2-1 conductive semiconductor layer 127a and the p-ohmic electrode increases, thereby possibly reducing the current injection efficiency.

[0084] The 2-1 conductive semiconductor layer 127a may have an aluminum composition greater than 1% and less than 50%. When the aluminum composition is greater than 50%, the 2-1 conductive semiconductor layer 127a may not be able to make sufficient ohmic contact with the p-ohmic electrode. When the aluminum composition is less than about 1%, the 2-1 conductive semiconductor layer 127a contains a composition close to GaN, and thus may absorb light.

[0085] The thickness of the 2-1 conductive semiconductor layer 127a may be 1 nm to 30 nm or 1 nm to 10 nm. As described above, the aluminum content contained in the 2-1 conductive semiconductor layer 127a is so low that it can be ohmic and thus absorb ultraviolet light. Therefore, in terms of light output power, it may be advantageous to adjust the 2-1 conductive semiconductor layer 127a to be as thin as possible.

[0086] However, when the thickness of the 2-1 conductive semiconductor layer 127a is controlled to be 1 nm or less, the 2-1 conductive semiconductor layer 127a may not be provided in some portions, and there may be a region in which the 2-2 conductive semiconductor layer 127b is exposed to the outside of the light emitting structure 120. In addition, when the thickness is greater than 30 nm, the amount of absorbed light is so large that light output power efficiency may be reduced.

[0087] The thickness of the 2-1 conductive semiconductor layer 127a may be smaller than the thickness of the 2-2 conductive semiconductor layer 127b. The thickness ratio of the 2-2 conductive semiconductor layer 127b to the 2-1 conductive semiconductor layer 127a may range from 1.5:1 to 20:1. When the thickness ratio is less than 1.5:1, the 2-2 conductive semiconductor layer 127b is so thin that current injection efficiency may be reduced. When the thickness ratio is greater than 20:1, the 2-1 conductive semiconductor layer 127a is too thin, and thus ohmic reliability may be reduced.

[0088] The aluminum composition of the 2-2 conductive semiconductor layer 127b may decrease as the 2-2 conductive semiconductor layer 127b is away from the active layer 126. In addition, the aluminum composition of the 2-1 conductive semiconductor layer 127a may decrease as the 2-1 conductive semiconductor layer 127a is away from the active layer 126.

[0089] In this case, the aluminum composition of the 2-1 conductive semiconductor layer 127a may be reduced to a greater extent than that of the 2-2 conductive semiconductor layer 127b. That is, the aluminum composition of the 2-1 conductive semiconductor layer 127a may vary more in the thickness direction than that of the 2-2 conductive semiconductor layer 127b.

[0090] The 2-2 conductive semiconductor layer 127b has a thickness greater than that of the 2-1 conductive semiconductor layer 127a and contains an aluminum composition higher than that of the well layer 126a. Therefore, the aluminum composition of the 2-2 conductive semiconductor layer 127b may be reduced relatively slowly.

[0091] However, the thickness of the 2-1 conductive semiconductor layer 127a is small, and the change of the aluminum composition is large. Therefore, the reduction degree of the aluminum composition of the 2-1 conductive semiconductor layer 127a is relatively large.

[0092] The 2-3 conductive semiconductor layer 127c may have a uniform aluminum composition. The thickness of the 2-3 conductive semiconductor layer 127c may be 20nm to 60nm. The 2-3 conductive semiconductor layer 127c may have an aluminum composition of 40% to 70%.

[0093] Figure 3 is a secondary ion mass spectrometry (SIMS) graph of the light emitting structure according to the first embodiment of the present invention, Figure 4 yes Figure 3 A partial enlarged view of .

[0094] See also Figure 3 and Figure 4 , the aluminum composition and the p-type impurity (Mg) composition of the light emitting structure may change as its thickness decreases. The aluminum composition of the second conductive semiconductor layer 127 may decrease, and the p-type impurity (Mg) composition of the second conductive semiconductor layer 127 may increase toward its surface.

[0095] The second conductive semiconductor layer 127 may have a ratio of a second shortest distance W2 to a first shortest distance W1 (W2:W1) ranging from 1:1.25 to 1:100 or 1:1.25 to 1:10, the second shortest distance W2 being the distance between the surface (first surface, with zero thickness) and the second point P21, and the first shortest distance W1 being the distance between the surface and the first point P11.

[0096] When the ratio of the second shortest distance W2 to the first shortest distance W1 (W2: W1) is less than 1:1.25, the first shortest distance W1 and the second shortest distance W2 are close, so that the aluminum composition changes rapidly. When the ratio W2: W1 is greater than 1:100, the thickness of the second conductive semiconductor layer 127 is too large, so that the crystallinity of the second conductive semiconductor layer 127 may be reduced or the stress applied to the substrate may be increased, thereby changing the wavelength of light emitted from the active layer.

[0097] Here, at the first point P11, the second conductive semiconductor has the same aluminum composition as the well layer 126a, which is a portion of the active layer closest to the second conductive semiconductor. The range of the first point P11 can be defined as a spectrum measured by SIMS. The range of the first point P11 can be defined as a portion of the second conductive semiconductor layer, the aluminum composition of which is the same as that of the well layer of the active layer.

[0098] In order to measure the first point P11, a method using SIMS spectrum can be applied, but the present invention is not limited thereto. For another example, TEM and XRD measurement methods can also be applied. In short, the first point P11 can be defined by SIMS spectrum.

[0099] The second point P21 may be a point of the SIMS spectrum at which the spectrum of the dopant (eg, Mg) of the second conductive semiconductor layer intersects with the spectrum of aluminum.

[0100] During measurement, the value unit of the dopant of the second conductive semiconductor layer may be different depending on the specific situation. However, the boundary area between the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b may be included in the range of a point where the area including the inflection point of the aluminum component of the second conductive semiconductor layer intersects with the spectrum of the dopant of the second conductive semiconductor layer. Therefore, the boundary area between the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b may be measured and its range may be defined.

[0101] However, the present invention is not limited thereto, and the second point P21 may be a point located within a region containing an aluminum composition of 5% to 55%. When the aluminum composition of the second point P21 is less than 5%, the 2-1 conductive semiconductor layer 127a is too thin, so that the power consumption efficiency of the semiconductor may be reduced. When the aluminum composition of the second point P21 is greater than 55%, the 2-1 conductive semiconductor layer 127a is too thick, so that the light extraction efficiency may be reduced. In this case, the aluminum composition of the second point P21 may be less than the aluminum composition of the first point P11. For example, the second point P21 may have an aluminum composition of 40% to 70%.

[0102] For example, the first shortest distance W1 may be 25 nm to 100 nm, and the second shortest distance W2 may be 1 nm to 20 nm.

[0103] The ratio of the first difference H1 to the second difference H2 (H1:H2) can be 1:1.2 to 1:10, the first difference H1 is the difference between the average aluminum composition of the electron blocking layer 129 and the aluminum composition of the first point P11, and the second difference H2 is the difference between the average aluminum composition of the electron blocking layer 129 and the aluminum composition of the second point P21.

[0104] When the ratio of the first difference to the second difference (H1:H2) is less than 1:1.2, the aluminum composition of the portion between the first point P11 and the second point P21 changes slowly, so it is difficult to reduce the aluminum composition of the contact layer. In addition, when the ratio of the first difference to the second difference (H1:H2) is greater than 1:10, the aluminum composition changes rapidly, so it is possible to increase the absorption probability of the light emitted by the active layer.

[0105] Figure 5 is a SIMS graph of the light emitting structure according to the second embodiment of the present invention, Figure 6 yes Figure 5 A partial enlarged view of Figure 7 is a SIMS graph of the light emitting structure according to the third embodiment of the present invention, Figure 8 yes Figure 7 A partial enlarged view of .

[0106] See also Figures 5 to 8 , it can be seen that the ratio of the second shortest distance W2 to the first shortest distance W1 is 1:1.25 to 1:100 or 1:1.25 to 1:10. For example, see Figure 8 , it can be seen that the first point P13 and the second point P23 are very close to each other.

[0107] In addition, it can be seen that the ratio of the first difference H1 to the second difference H2 (H1:H2) can be 1:1.2 to 1:10, the first difference H1 is the difference between the average aluminum composition of the electron blocking layer 129 and the aluminum composition of the first points P12 and P13, and the second difference H2 is the difference between the average aluminum composition of the electron blocking layer 129 and the aluminum composition of the second points P22 and P23.

[0108] When such conditions are satisfied, the aluminum composition of the surface of the second conductive semiconductor layer 127 may be adjusted to 1% to 10%.

[0109] Fig. 9 is a conceptual view of a semiconductor structure according to an embodiment of the present invention, Fig.10 is a graph illustrating aluminum composition of a semiconductor structure according to an embodiment of the present invention.

[0110] See also Fig. 9 and 10 The semiconductor device according to the embodiment includes a semiconductor structure 120 including a first conductive semiconductor layer 124 , a second conductive semiconductor layer 127 , and an active layer 126 , wherein the active layer 126 is disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127 .

[0111] The semiconductor structure 120 according to an embodiment of the present invention can output ultraviolet wavelength light. For example, the semiconductor structure 120 can output near ultraviolet wavelength light (UV-A), far ultraviolet wavelength light (UV-B), or deep ultraviolet wavelength light (UV-C). The wavelength range can be determined by the aluminum composition of the semiconductor structure 120.

[0112] For example, the wavelength of near ultraviolet wavelength light (UV-A) may be 320nm to 420nm, the wavelength of far ultraviolet wavelength light (UV-B) may be 280nm to 320nm, and the wavelength of deep ultraviolet wavelength light (UV-C) may be 100nm to 280nm.

[0113] When the semiconductor structure 120 emits ultraviolet wavelength light, each semiconductor layer of the semiconductor structure 120 may include a material containing aluminum, In x1 Al y1 Ga1-x1-y1 N(0 ≤ x1 ≤ 1, 0 < y1 ≤ 1, 0 ≤ x1 + y1 ≤ 1). Here, the aluminum component can be expressed as the ratio of the atomic weight of Al to the total atomic weight, and the total atomic weight includes the atomic weight of In, the atomic weight of Ga, and the atomic weight of Al. For example, when the aluminum component is 40% and the Ga component is 60%, the material can be Al 40 Ga 60 N.

[0114] Moreover, when describing embodiments, the high or low of the components can be understood by the difference in the component percentages (and / or percentage points) of each semiconductor layer. For example, when the first semiconductor layer has an aluminum component of 30% and the second conductive semiconductor layer has an aluminum component of 60%, the aluminum component of the second conductive semiconductor layer can be expressed as 30% higher than that of the first semiconductor layer.

[0115] The first conductive semiconductor layer 124 can be made of a III-V or II-VI compound semiconductor and can be doped with a first dopant. The first conductive semiconductor layer 124 can be selected from those with the empirical formula In x1 Al y1 Ga 1-x1-y1 N(0 ≤ x1 ≤ 1, 0 ≤ y1 ≤ 1, and 0 ≤ x1 + y1 ≤ 1) of various semiconductor materials (e.g., AlGaN, AlN, InAlGaN, etc.). Moreover, the first dopant can 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 can be an n-type semiconductor layer. However, the present invention is not limited thereto, and the first conductive semiconductor layer 124 can be a p-type semiconductor layer.

[0116] The first conductive semiconductor layer 124 can include a 1-1 conductive semiconductor layer 124a, a 1-2 conductive semiconductor layer 124c, and an intermediate layer 124b, and the intermediate layer 124b is disposed between the 1-1 conductive semiconductor layer 124a and the 1-2 conductive semiconductor layer 124c.

[0117] The 1-1 conductive semiconductor layer 124a can have an aluminum component of 50% to 80%. When the aluminum component of the 1-1 conductive semiconductor layer 124a is greater than 50%, the light extraction efficiency can be improved by reducing the absorption rate of deep ultraviolet wavelength light (UV-C) emitted from the active layer 126. When the aluminum component of the 1-1 conductive semiconductor layer 124a is less than 80%, the current injection characteristics of the active layer 126 and the current diffusion characteristics of the 1-1 conductive semiconductor layer 124a can be ensured.

[0118] The 1-2 conductive semiconductor layer 124c may be disposed closer to the active layer 126 than the 1-1 conductive semiconductor layer 124a. The aluminum composition of the 1-2 conductive semiconductor layer 124c may be lower than that of the 1-1 conductive semiconductor layer 124a.

[0119] When the semiconductor structure 120 emits deep ultraviolet wavelength light (UV-C), the aluminum composition of the 1-2 conductive semiconductor layer 124 c may be in the range of 40% to 70%.

[0120] When the aluminum composition of the 1-2 conductive semiconductor layer 124c is greater than or equal to 40%, light extraction efficiency may be improved by reducing the absorptivity of deep ultraviolet wavelength light (UV-C) emitted from the active layer 126. When the aluminum composition of the 1-2 conductive semiconductor layer 124c is less than or equal to 70%, current injection characteristics of the active layer 126 and current diffusion characteristics of the 1-2 conductive semiconductor layer 124c may be ensured.

[0121] The aluminum composition of the 1-1 conductive semiconductor layer 124a and the aluminum composition of the 1-2 conductive semiconductor layer 124c are higher than that of the well layer 126a. Therefore, when the active layer 126 emits ultraviolet wavelength light, the absorption rate of ultraviolet wavelength light in the semiconductor structure 120 can be reduced.

[0122] In addition, when the aluminum composition of the 1-2 conductive semiconductor layer 124c is higher than that of the 1-1 conductive semiconductor layer 124a, light can be easily extracted from the active layer 126 to the outside of the semiconductor structure 120 due to the difference in refractive index. Therefore, the light extraction efficiency of the semiconductor structure 120 can be improved.

[0123] The 1-2 conductive semiconductor layer 124c may be thinner than the 1-1 conductive semiconductor layer 124a. The thickness of the 1-1 conductive semiconductor layer 124a may be greater than or equal to 130% of the thickness of the 1-2 conductive semiconductor layer 124c. According to this configuration, the intermediate layer 124b is provided after the thickness of the 1-1 conductive semiconductor layer 124a having a high aluminum content is sufficiently ensured. Therefore, the overall crystallinity of the semiconductor structure 120 may be improved.

[0124] The aluminum composition of the intermediate layer 124b may be lower than the aluminum composition of the first conductive semiconductor layer 124 and the aluminum composition of the second conductive semiconductor layer 127. During a laser lift-off (LLO) process for removing a growth substrate, the intermediate layer 124b may be used to absorb laser light emitted to the semiconductor structure 120 to prevent damage to the active layer 126. Therefore, the semiconductor device according to the embodiment may prevent damage to the active layer 126 during the LLO process, thereby enhancing optical output power and electrical characteristics.

[0125] Moreover, when the intermediate layer 124b contacts the first electrode, the aluminum composition of the intermediate layer 124b can be lower than the aluminum composition of the 1-1 conductive semiconductor layer 124a and the aluminum composition of the 1-2 semiconductor layer 124c to reduce the resistance between the intermediate layer 124b and the first electrode, thereby ensuring current injection efficiency.

[0126] The thickness and aluminum composition of the intermediate layer 124b may be appropriately adjusted to absorb laser light emitted to the semiconductor structure 120 during the LLO process. Therefore, the aluminum composition of the intermediate layer 124b may correspond to the wavelength of the laser light used during the LLO process.

[0127] When the wavelength of the LLO laser is 200 nm to 300 nm, the intermediate layer 124 b may have an aluminum composition of 30% to 70% and a thickness of 1 nm to 10 nm.

[0128] For example, when the wavelength of the LLO laser is less than 270 nm, the aluminum composition of the intermediate layer 124 b may be increased to correspond to the wavelength of the LLO laser. For example, the aluminum composition of the intermediate layer 124 b may be increased to 50% to 70%.

[0129] When the aluminum content of the intermediate layer 124b is higher than the aluminum content of the well layer 126a, the intermediate layer 124b may not absorb the light emitted from the active layer 126. Therefore, the light extraction efficiency can be improved. According to an embodiment of the present invention, the wavelength of the LLO laser may be smaller than the wavelength of the light emitted from the well layer 126a. Therefore, the intermediate layer 124b may have a suitable aluminum composition so that the intermediate layer 124b absorbs the LLO laser but does not absorb the light emitted from the well layer 126a.

[0130] The intermediate layer 124b may include a first intermediate layer (not shown) having an aluminum composition lower than that of the first conductive semiconductor layer 124, and a second intermediate layer (not shown) having an aluminum composition higher than that of the first conductive semiconductor layer 124. A plurality of first intermediate layers and a plurality of second intermediate layers may be alternately disposed.

[0131] The active layer 126 may be disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127. The active layer 126 may include a plurality of well layers 126a and a plurality of barrier layers 126b. The well layer 126a is a layer in which first carriers (electrons or holes) injected through the first conductive semiconductor layer 124 are combined with second carriers (holes or electrons) injected through the second conductive semiconductor layer 127. When the first carriers (or second carriers) in the conduction band and the second carriers (or first carriers) in the valence band are recombined in the well layer 126a of the active layer 126, light having a wavelength corresponding to the energy level difference (band gap) between the conduction band and the valence band of the well layer 126a may be generated.

[0132] The active layer 126 may have 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, but is not limited thereto.

[0133] The active layer 126 may include a plurality of well layers 126a and a plurality of barrier layers 126b. Each of these well layers 126a and barrier layers 126b may have an empirical formula of In x2 Al y2 Ga 1-x2-y2 N (0 ≤ x2 ≤ 1, 0 < y2 ≤ 1, and 0 ≤ x2 + y2 ≤ 1). The aluminum content contained in the well layer 126a may vary according to the emission wavelength.

[0134] 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. Moreover, the second conductive semiconductor layer 127 may be doped with a second dopant.

[0135] The second conductive semiconductor layer 127 may be made of a semiconductor material having an empirical formula of Inx 5A l y2 G a1-x5-y2 N (0 ≤ x5 ≤ 1, 0 < y2 ≤ 1, and 0 ≤ x5 + y2 ≤ 1) or a material selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP.

[0136] 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. However, the present invention is not limited thereto, and the second conductive semiconductor layer 124 may be an n-type semiconductor layer.

[0137] The second conductive semiconductor layer 127 may include a 2-1 conductive semiconductor layer 127a, a 2-2 conductive semiconductor layer 127b, and a 2-3 conductive semiconductor layer 127c. The aluminum content of the 2-1 conductive semiconductor layer 127a may be lower than the aluminum content of the 2-2 conductive semiconductor layer 127b and the 2-3 conductive semiconductor layer 127c.

[0138] The barrier layer 129 may be provided between the active layer 126 and the second conductive semiconductor layer 127. The barrier layer 129 may block the electron flow provided from the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127, thereby increasing the possibility of electrons and holes recombining with each other in the active layer 126. The energy band gap of the barrier layer 129 may be higher than the energy band gap of the active layer 126 and / or the second conductive semiconductor layer 127. The barrier layer 129 is doped with a second dopant and may thus be defined as a partial region of the second conductive semiconductor layer 127.

[0139] The blocking layer 129 may be made of a material selected from a variety of semiconductor materials with the empirical formula In x1 Al y1 Ga 1-x1-y1 N (0 ≤ x1 ≤ 1, 0 < y1 ≤ 1, and 0 ≤ x1 + y1 ≤ 1), such as, for example, AlGaN, AlN, InAlGaN, etc., but not limited thereto.

[0140] According to an embodiment, the first conductive semiconductor layer 124, the active layer 126, the second conductive semiconductor layer 127, and the blocking layer 129 may all contain aluminum. Therefore, the first conductive semiconductor layer 124, the active layer 126, the second conductive semiconductor layer 127, and the blocking layer 129 may contain components such as AlGaN, InAlGaN, or AlN.

[0141] The aluminum content of the blocking layer 129 may be higher than that of the well layer 126a. For example, the aluminum content of the blocking layer 129 may be in the range of 50% to 100%. When the aluminum content of the blocking layer 129 is greater than or equal to 50%, the blocking layer 129 may have a sufficient energy barrier to block the first carriers and may not absorb the light emitted from the active layer 126.

[0142] The blocking layer 129 may include a 1-1 portion 129a and a 1-2 portion 129c.

[0143] The aluminum content of the 1-1 portion 129a may increase from the first conductive semiconductor layer 124 toward the second conductive semiconductor layer 127.

[0144] The aluminum content of the 1-1 portion 129a may be 80% to 100%. Therefore, the 1-1 portion 129a of the blocking layer 129 may be the portion with the highest aluminum content in the semiconductor structure 120.

[0145] The 1-1 portion 129a may include AlGaN or AlN. Alternatively, the 1-1 portion 129a may be a superlattice layer in which AlGaN and AlN are alternately arranged.

[0146] The thickness of the 1-1 portion 129a may be approximately 0.1 nm to approximately 4 nm. In order to effectively block the movement of the first carriers to the second conductive semiconductor layer 127, the 1-1 portion 129a may be formed with a thickness of 0.1 nm or greater. Moreover, in order to ensure the injection efficiency of the second carriers injected from the second conductive semiconductor layer 127 into the active layer 126, the 1-1 portion 129a may be formed with a thickness of 4 nm or less.

[0147] In one embodiment, the 1-1 portion 129a is formed to have a thickness of 0.1 nm to 4 nm to ensure hole injection efficiency and electron blocking efficiency, but is not limited thereto. For example, when it is necessary to selectively further ensure any one of the first carrier blocking function and the second carrier injection function, there may be a deviation from the aforementioned numerical range.

[0148] The 1-3 portion 129b disposed between the 1-1 portion 129a and the 1-2 portion 129c may include an undoped portion containing no dopant. Therefore, the 1-3 portion 129b may serve to prevent the second dopant from diffusing from the second conductive semiconductor layer 127 to the active layer 126.

[0149] The second conductive semiconductor layer 127 may include a 2-1 conductive semiconductor layer 127a, a 2-2 conductive semiconductor layer 127b, and a 2-3 conductive semiconductor layer 127c.

[0150] The thickness of the 2-2 conductive semiconductor layer 127b may be greater than 10nm and less than 50nm. For example, the thickness of the 2-2 conductive semiconductor layer 127b may be equal to 25nm. When the thickness of the 2-2 conductive semiconductor layer 127b is greater than or equal to 10nm, the current diffusion characteristics of the 2-2 conductive semiconductor layer 127b can be ensured. In addition, when the thickness is less than or equal to 50nm, the injection efficiency of the second carrier into the active layer 126 can be ensured and the absorption rate of the light emitted by the active layer 126 in the 2-2 conductive semiconductor layer 127b can be reduced.

[0151] The 2-2 conductive semiconductor layer 127b may contain an aluminum content higher than that of the well layer 126a. In order to generate ultraviolet light, the aluminum content of the well layer 126a may be about 30% to about 70%. Therefore, the aluminum content of the 2-2 conductive semiconductor layer 127b may be in the range of 40% to 80%.

[0152] When the aluminum composition of the 2-2 conductive semiconductor layer 127b is greater than or equal to 40%, light absorption can be reduced, and when the aluminum composition of the 2-2 conductive semiconductor layer 127b is less than or equal to 80%, the degradation of the current injection efficiency can also be slowed down. For example, when the aluminum composition of the well layer 126a is equal to 30%, the aluminum composition of the 2-2 conductive semiconductor layer 127b can be equal to 40%.

[0153] The aluminum composition of the 2-1 conductive semiconductor layer 127a may be lower than that of the well layer 126a. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is higher than that of the well layer 126a, the 2-1 conductive semiconductor layer 127a and the second electrode cannot be sufficiently ohmically contacted due to the increased resistance therebetween, and current injection efficiency may also be reduced.

[0154] The aluminum composition of the 2-1 conductive semiconductor layer 127a may be in the range of 1% to 50%. When the aluminum composition is less than or equal to 50%, the resistance of the second electrode may be reduced. When the aluminum composition is greater than or equal to 1%, light absorption in the 2-1 conductive semiconductor layer 127a may be reduced. The aluminum composition of the 2-1 conductive semiconductor layer 127a may be lower than the aluminum composition of the intermediate layer 124.

[0155] The thickness of the 1-1 conductive semiconductor layer 127a may be 1 nm to 30 nm. Therefore, since the 2-1 conductive semiconductor layer 127a can absorb ultraviolet light, it may be advantageous in terms of light output power to adjust the 2-1 conductive semiconductor layer 127a to be as thin as possible.

[0156] However, when the thickness of the 2-1 conductive semiconductor layer 127a is greater than or equal to 1nm, the resistance of the 2-1 conductive semiconductor layer 127a can be reduced, thereby improving the electrical characteristics of the semiconductor device. In addition, when the thickness is less than or equal to 30nm, the light output power efficiency can be improved by reducing the amount of light absorbed by the 2-1 conductive semiconductor layer 127a.

[0157] The thickness of the 2-1 conductive semiconductor layer 127a may be less than the thickness of the 2-2 conductive semiconductor layer 127b. The thickness ratio of the 2-1 conductive semiconductor layer 127a to the 2-2 conductive semiconductor layer 127b may be in the range of 1:1.5 to 1:20. When the thickness ratio is greater than 1:1.5, the thickness of the 2-2 conductive semiconductor layer 127b increases, so that the current injection efficiency can be improved. In addition, when the thickness ratio is less than 1:20, the thickness of the 2-1 conductive semiconductor layer 127a increases, so that the degradation of crystallinity can be slowed down. When the 2-1 conductive semiconductor layer 127a is too thin, the aluminum component is required to change rapidly within the thickness range, so that the crystallinity can be reduced.

[0158] The aluminum content contained in the 2-2 conductive semiconductor layer 127b may decrease as it is farther from the active layer 126. In addition, the aluminum content contained in the 2-1 conductive semiconductor layer 127a may decrease as it is farther from the active layer 126.

[0159] In this case, the reduction degree of aluminum in the thickness of the 2-1 conductive semiconductor layer 127a may be greater than the reduction degree of aluminum in the thickness of the 2-2 conductive semiconductor layer 127b. That is, the change in aluminum composition of the 2-1 conductive semiconductor layer 127a in the thickness direction may be greater than the change in aluminum composition of the 2-2 conductive semiconductor layer 127b in the thickness direction.

[0160] The aluminum composition of the 2-1 conductive semiconductor layer 127a may be lower than that of the well layer 126a to achieve low contact resistance with the second electrode. Therefore, the 2-1 conductive semiconductor layer 127a may absorb a portion of light emitted from the well layer 126a.

[0161] Therefore, in order to suppress light absorption, the 2-1 conductive semiconductor layer 127a may be formed to have a thickness of 1 nm to 30 nm.

[0162] As a result, the thickness of the 2-1 conductive semiconductor layer 127a is small but the variation of aluminum is relatively large. Therefore, the 2-1 conductive semiconductor layer 127a may have a relatively high reduction degree of aluminum in thickness.

[0163] On the other hand, the 2-2 conductive semiconductor layer 127b is thicker than the 2-1 conductive semiconductor layer 127a, and contains an aluminum component higher than that of the well layer 126a. Thus, the aluminum contained in the 2-2 conductive semiconductor layer 127b may be reduced relatively slowly.

[0164] Since the 2-1 conductive semiconductor layer 127a is relatively thin and the aluminum composition varies greatly in thickness, the aluminum composition may be changed while the 2-1 conductive semiconductor layer 127a is grown relatively slowly.

[0165] The 2-3 conductive semiconductor layer 127c may have a uniform aluminum composition. The thickness of the 2-3 conductive semiconductor layer 127c may be 20nm to 60nm. The 2-3 conductive semiconductor layer 127c may have an aluminum composition of 40% to 70%. When the aluminum composition of the 2-3 conductive semiconductor layer 127c is greater than or equal to 40%, it is unlikely to reduce the crystallinity of the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b. When the aluminum composition is less than 70%, the reduction in crystallinity due to the rapid change in the aluminum composition of the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b can be prevented, thereby enhancing the electrical characteristics of the semiconductor device.

[0166] As described above, the thickness of the 2-1 conductive semiconductor layer 127a may be 1 nm to 10 nm, the thickness of the 2-2 conductive semiconductor layer 127b may be 10 nm to 50 nm, and the thickness of the 2-3 conductive semiconductor layer 127c may be 20 nm to 60 nm.

[0167] Therefore, the ratio of the thickness of the 2-1 conductive semiconductor layer 127a to the total thickness of the second conductive semiconductor layer 127 may be in the range of 1:3 to 1:120. When the ratio is greater than 1:3, the 2-1 conductive semiconductor layer 127a may ensure electrical characteristics (e.g., operating voltage) of the semiconductor device. When the ratio is less than 1:120, the 2-1 conductive semiconductor layer 127a may ensure optical characteristics (e.g., light output power) of the semiconductor device. However, the present invention is not limited thereto, and the ratio of the thickness of the 2-1 conductive semiconductor layer 127a to the total thickness of the second conductive semiconductor layer 127 may be in the range of 1:3 to 1:150 or 1:3 to 1:70.

[0168] The second conductive semiconductor layer 127 according to an embodiment of the present invention may have a first point P1 and a third point P3, where the aluminum content of the semiconductor structure is the highest at the first point P1 and the aluminum content of the semiconductor structure is the lowest at the third point P3. Here, the first point P1 may be the 1-1 portion 129a of the barrier layer 129 having the highest aluminum content, and the third point P3 may be the 2-1 conductive semiconductor layer 127a having the lowest aluminum content.

[0169] The first conductive semiconductor layer 124 may have a second point P2, at which the aluminum content of the first conductive semiconductor layer is the highest, and a fourth point P4, at which the aluminum content of the first conductive semiconductor layer is the lowest. The second point P2 may be the 1-1 conductive semiconductor layer 124a and / or the 1-2 conductive semiconductor layer 124c, and the fourth point P4 may be the intermediate layer 124b.

[0170] The 1-1 portion 129a may have an aluminum composition of 80% to 100%. The 2-1 conductive semiconductor layer 127a may have an aluminum composition of 1% to 50%. In this case, the 2-1 conductive semiconductor layer 127a may contain an aluminum composition lower than that contained in the well layer 126a.

[0171] Therefore, the aluminum composition ratio between the third point P3 and the first point P1 may be in the range of 1:4 to 1:100. When the aluminum composition ratio is greater than or equal to 1:4, the aluminum composition of the first point P1 may increase, thereby effectively blocking the first carrier from passing through the second conductive semiconductor layer. When the aluminum composition ratio is less than or equal to 1:100, the aluminum composition of the third point P3 may increase, thereby reducing light absorption at the third point P3.

[0172] The 1-1 conductive semiconductor layer 124a may have an aluminum composition of 50% to 80%. The intermediate layer 124b may have an aluminum composition of 30% to 70%. In this case, the aluminum composition of the intermediate layer 124b may be lower than that of the 1-1 conductive semiconductor layer. Therefore, the aluminum composition ratio between the fourth point P4 and the second point P2 may be in the range of 1:0.5 to 1:0.9.

[0173] When the aluminum composition ratio is greater than or equal to 1:0.5, the aluminum composition of the 1-1 conductive semiconductor layer 124a may increase to improve crystallinity. When the aluminum composition ratio is less than or equal to 1:0.9, the aluminum composition of the intermediate layer 124b may increase to reduce absorption of ultraviolet wavelength light.

[0174] Fig.11a and Fig.11b shows SIMS data of a semiconductor structure according to an embodiment of the present invention, Fig.11c and Fig.11d shows SIMS data of a semiconductor structure according to another embodiment of the present invention, Fig.12 It is shown Figures 11a to 11d Aluminum ion strength diagram, Fig.13a It is shown Fig.12 (a) is a partially enlarged view of SIMS data. Fig.13b It is shown Fig.12 (b) Plot of SIMS data converted to a linear scale.

[0175] See also Fig.11a , the semiconductor structure may have components of aluminum (Al), gallium (Ga), a first dopant, a second dopant, oxygen (O), and carbon (C), which vary in a direction from the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127. The first dopant may be silicon (Si), and the second dopant may be magnesium (Mg). However, the present invention is not limited thereto.

[0176] SIMS data can be analyzed by time-of-flight secondary ion mass spectrometry (TOF-SIMS).

[0177] SIMS data can be analyzed by emitting primary ions onto a target surface and counting the number of secondary ions ejected. In this case, the O2 + , Cs + 、Bi + In selecting primary ions, the acceleration voltage can be adjusted to be in the range of about 20 keV to 30 keV, the emission current can be adjusted to be in the range of about 0.1 pA to 5.0 pA, and the target area can be 20 nm×20 nm.

[0178] SIMS data may be obtained by collecting a secondary ion mass spectrum while gradually etching the surface (a point where the depth is zero) of the second conductive semiconductor layer in a direction toward the first conductive semiconductor layer.

[0179] However, the present invention is not limited thereto, and different measurement conditions may be employed to detect the AlGaN-based and / or GaN-based semiconductor material, the first dopant material, and the second dopant material.

[0180] In addition, the SMIS analysis results can be obtained by interpreting the spectrum of secondary ion intensity or doping concentration of each material. When the secondary ion intensity or doping concentration is interpreted, the results can include noise generated by a factor of 0.9 to 1.1. Therefore, the term "same / equivalent" means including noise proportional to a factor of 0.9 to 1.1 relative to a specific secondary ion intensity or doping concentration.

[0181] Figures 11a to 11d The aluminum and gallium in the SIMS data are the spectral data of the secondary ion intensity, and the first dopant, the second dopant, oxygen and carbon are the data obtained by measuring the doping concentration. That is, Figures 11a to 11d SIMS data and doping concentration data are presented in a single figure.

[0182] Reference Fig.11a , which shows that the spectrum of the intensity level of aluminum and the spectrum of the concentration of the first dopant and the second dopant partially intersect each other. However, the data on the intensity and the data on the dopant concentration may have independent relationships.

[0183] For example, it is shown that the aluminum ion intensity and the doping concentration of the second dopant intersect each other near the surface (the point where the depth is zero). However, when the doping concentration reference point (i.e., the lowest point of the Y-axis located on the left side of the figure) is set to be lower, the doping concentration may decrease on the graph. For example, when the reference point of the second dopant doping concentration decreases from 1.00E+14 to 1.00E+12, the second dopant concentration decreases on the graph, and thus the second dopant data and the aluminum data may not intersect each other.

[0184] The measurement method of the concentration of the first dopant, the second dopant, oxygen or carbon is not limited to a specific form. Also, in the present embodiment, the vertical axis (ie, the Y axis) is shown and converted into a logarithmic scale.

[0185] It can be seen that the aluminum ion intensity gradually increases with the depth from the surface, and after the maximum intensity point, the aluminum ion intensity alternately increases and decreases. Since the material AlGaN is formed by replacing Al atoms with Ga atoms in GaN-based semiconductor materials, the gallium ion intensity can be symmetrical with the aluminum ion intensity.

[0186] The ion intensity according to the embodiment can increase or decrease according to the measurement conditions. However, the secondary ion intensity (e.g., aluminum ion) can generally increase on the graph when the primary ion intensity increases, and the secondary ion intensity can generally decrease when the primary ion intensity decreases. Therefore, even if the measurement conditions change, the change in ion intensity in the thickness direction can also be similar.

[0187] The doping concentration of the second dopant may be the highest on the surface and may gradually decrease as it moves away from the surface. The second dopant may be present in all regions of the second conductive semiconductor layer and some regions of the active layer, but is not limited thereto. The second dopant may be arranged only in the second conductive semiconductor layer, but may diffuse upward to the active layer. Therefore, the injection efficiency of the second dopant into the active layer may be improved. However, when the second dopant diffuses upward to the first conductive semiconductor layer, leakage current of the semiconductor device and / or non-radiative recombination between the first carrier and the second carrier may occur, thereby reducing the reliability and / or luminous efficiency of the semiconductor device.

[0188] The first dopant may have a portion R1 between the first conductive semiconductor layer and the active layer, in which the concentration of the first dopant is lower than the concentration of oxygen. The first dopant may even be partially distributed in the active layer. Therefore, the injection efficiency of the first carrier injected into the active layer can be improved, and the radiation recombination efficiency between the first carrier and the second carrier can also be improved.

[0189] Can confirm Figures 11b to 11d Shown with Fig.11a Same trend.

[0190] See also Fig.12 and Fig.13a , the aluminum ion strength may include the aluminum ion strengths of the first to sixth points P1, P2, P3, P4, P5, and P6. Fig.12 Part (a) shows Fig.11a The aluminum ion strength, Fig.12 Part (b) shows Fig.11b The aluminum ion strength, Fig.12 Part (c) shows Fig.11c The aluminum ion strength, Fig.12 Part (d) shows Fig.11d Aluminum ion strength.

[0191] Fig.12 Part (c) and Fig.12 Part (d) shows the Fig.12 The distribution of the aluminum ion intensity of part (a) in FIG. 1 is similar to that of part (a), except for the concave-convex portion P7 where the ion intensity changes between the first point P1 and the third point P3. Fig.12 Part (c) and Fig.12 In the embodiment of part (d) of FIG. 1 , there is a structure in which a superlattice layer is further provided on the barrier layer.

[0192] The aluminum ion intensity of the first point P1 may be the highest in the semiconductor structure 120. Since the aluminum ion intensity of the first point P1 is the highest, the first carrier and the second carrier may be prevented from non-radiatively recombining in the second conductive semiconductor layer. Therefore, the optical output power of the semiconductor device may be improved. The first point P1 may be a region corresponding to the 1-1 portion 129a of the barrier layer 129, but is not limited thereto.

[0193] The secondary ion intensity of the second point P2 may correspond to a point having the highest aluminum ion intensity among a plurality of points having aluminum ion intensity extending from the first point P1 along the first direction D (ie, a direction in which the depth increases).

[0194] The second point P2 may be a point where the aluminum ion intensity of the first conductive semiconductor layer 124 is the highest, and may also be a point closest to the active layer 126 in the first conductive semiconductor layer 124 .

[0195] The second point P2 can be used to balance the concentration or density of the first carriers and the second carriers recombined in the active layer by reducing the energy of the first carriers injected into the active layer in the first conductive semiconductor layer 124. Therefore, the light emitting efficiency can be increased, thereby improving the light output power characteristics of the semiconductor device.

[0196] The third ion intensity at the third point P3 may correspond to a point where the aluminum ion intensity in a direction from the first point P1 to the surface of the semiconductor structure 120 (a direction opposite to the first direction) is the lowest.

[0197] When the third point P3 contacts the second electrode, the resistance between the third point P3 and the second electrode can be low because the aluminum ion intensity of the third point P3 is the lowest. Therefore, the injection efficiency of injecting current into the semiconductor structure 120 through the second electrode can be ensured.

[0198] The fourth ion intensity at the fourth point P4 may correspond to a point where the aluminum ion intensity is lowest in the first direction from the second point P2 .

[0199] When the LLO process is applied during the process of the semiconductor device, the fourth point P4 may absorb laser light so that the laser light does not penetrate the active layer, thereby preventing damage to the active layer caused by the LLO process.

[0200] Moreover, when the fourth point P4 contacts the first electrode, the injection efficiency of the current injected into the semiconductor structure can be improved by reducing the resistance between the first electrode and the fourth point P4. In this regard, the aluminum ion intensity of the fourth point P4 can be the point with the lowest aluminum ion intensity in the first direction from the second point P2.

[0201] The fifth point P5 may be disposed between the second point P2 and the fourth point P4. The aluminum ion strength of the fifth point P5 may be between the aluminum ion strength of the second point P2 and the aluminum ion strength of the fourth point P4. The fifth point P5 may be a single specific point, or may be formed as a single layer. By uniformly distributing the current injected via the fourth point P4 in the layer including the fifth point P5, it may be improved to make the density per unit area of ​​the current injected into the active layer uniform.

[0202] In addition, a plurality of points (or layers) may be separately arranged along the first direction D from the fourth point P4, and the aluminum ion strength of these points (or layers) is the same as or similar to the aluminum ion strength of the fifth point P5. That is, there may be such a portion in which the ion strength increases along the first direction from the fourth point P4. Therefore, the fourth point P4 may be arranged between a plurality of points (or layers) and the aluminum ion strength of these points (or layers) is the same as the aluminum ion strength of the fifth point P5. However, the present invention is not limited thereto, and the aluminum ion strength of the region separated from the fifth point P5 in the first direction D and spaced farther than the fourth point P4 in the first direction D may be higher than the aluminum ion strength of the fifth point P5.

[0203] The tenth point P10 may be disposed between the first point P1 and the third point P3 and may have the same aluminum ion strength as the point S22 which is located between the first point P1 and the second point P2 and has the lowest ion strength.

[0204] The region between the tenth point P10 and the third point P3 may have a thickness of 1 nm to 30 nm to suppress absorption of light emitted from the semiconductor device and reduce contact resistance with the second electrode.

[0205] Also, the conductivity of the third point P3 electrically connected to the second electrode may be lower than the conductivity of the fourth point P4 connected to the first electrode. Therefore, the ion strength of the third point P3 may be lower than the ion strength of the fourth point P4.

[0206] An average change in aluminum ion strength between the tenth point P10 and the third point P3 may be greater than an average change in aluminum ion strength between the first point P1 and the tenth point P10. Here, the average change may be obtained by dividing the maximum change in aluminum ion strength by the thickness.

[0207] The region S11 between the third point P3 and the tenth point P10 may have a portion where the aluminum ion intensity decreases toward the surface S0, and the region S11 may also have an inverse portion P6 where the aluminum ion intensity does not decrease toward the surface S0. The inverse portion P6 may be a portion where the aluminum ion intensity increases toward the surface S0 or remains unchanged.

[0208] When the reverse portion P6 is disposed in the region between the third point P3 and the tenth point P10, the current injected through the third point P3 can be uniformly diffused, and thus the current density injected into the active layer can be controlled to be uniform. Therefore, the optical output power characteristics and electrical characteristics of the semiconductor device can be enhanced.

[0209] The reverse portion P6 may be controlled by temperature. For example, the region between the third point P3 and the tenth point P10 may have an aluminum composition controlled by temperature control. In this case, when the temperature is reduced too fast, the crystallinity of the second conductive semiconductor layer may be significantly reduced.

[0210] Therefore, in the process of continuously lowering or raising the temperature, a large amount of aluminum is immediately contained when the temperature that has been lowered is raised, and thus the reverse portion P6 can be formed.

[0211] That is, in the process of forming the third point P3 after the tenth point P10 having the same aluminum ion strength as the point with the lowest aluminum ion strength in the active layer is formed, the aluminum composition can be controlled by temperature, and the reverse part P6 can be arranged to ensure the crystallinity of the second conductive semiconductor layer and ensure the current diffusion characteristics.

[0212] However, the present invention is not limited thereto. According to another embodiment, in order to further ensure the current injection characteristics, the aluminum ion intensity may be continuously reduced in the direction from the tenth point P10 to the third point P3 without the inversion portion P6.

[0213] See also Fig.13a , in the graph of aluminum ion intensity, the semiconductor structure may include a first portion S1, a second portion S2, and a third portion S3 in a direction of increasing depth.

[0214] The first portion S1 may be disposed between the first point P1 and the third point P3, and may be configured as the second conductive semiconductor layer 127. The second portion S2 may be disposed between the first point P1 and the second point P2, and may be configured as the active layer 126. The third portion S3 may be disposed along the first direction from the second point P2, and may be configured as the first conductive semiconductor layer 124.

[0215] The second portion S2 may be disposed between the first point P1 and the second point P2. As described above, the first point P1 may be a point where the aluminum intensity of aluminum in the semiconductor structure is the highest, the second point P2 may be a point disposed separately in the first direction (the direction of increasing depth) away from the surface on the graph, and the ion intensity of the second point P2 is higher than the maximum ion intensity (peak ion intensity) of the second portion S2.

[0216] However, the present invention is not limited thereto, and the height of the second point may be the same as the height of the fifth point. In this case, the second portion may be disposed between the first point and the fifth point.

[0217] The second portion S2 is a portion corresponding to the active layer 126, and may have a plurality of peaks S21 and a plurality of valleys S22. The valleys S22 may be the ion strength of the well layer, and the peaks S21 may be the ion strength of the barrier layer.

[0218] An ion intensity ratio M1 between the valley S22 with the lowest ion intensity and the first point P1 may be 1:0.4 to 1:0.6, and an ion intensity ratio M2 between the valley S22 and the peak S21 may be 1:0.5 to 1:0.75.

[0219] When the aluminum ion intensity ratio M1 of the point of the valley S22 with the lowest ion intensity to the first point P1 is greater than or equal to 1:0.4, the crystallinity of the second conductive semiconductor layer between the first point P1 and the third point P3, which are closer than the active layer, can be ensured, and the first carrier injection into the second conductive semiconductor layer can be prevented to increase the possibility of radiation recombination in the active layer. Therefore, the optical output power characteristics of the semiconductor device can be improved.

[0220] In addition, when the ion strength ratio M1 is less than or equal to 1:0.6, the crystallinity of the second conductive semiconductor layer between the first point P1 and the third point P3, which are disposed closer to the surface than the active layer, may be ensured.

[0221] When the ion intensity ratio M2 of the trough S22 to the peak S21 is greater than or equal to 1:0.5, the barrier layer can effectively prevent carriers from flowing from the well layer included in the active layer to the first conductive semiconductor layer and / or the second conductive semiconductor layer to increase the possibility of radiative recombination in the well layer, thereby enhancing the light output power characteristics of the semiconductor device.

[0222] In addition, when the ion strength ratio M2 is less than or equal to 1:0.75, the crystallinity of the semiconductor structure can be ensured, the wavelength change due to strain can be reduced, and / or the possibility of radiative recombination can be increased by reducing the stress generated by the lattice constant difference between the well layer and the barrier layer.

[0223] The ratio of the ratio M1 to the ratio M2 may satisfy the range of 1:0.3 to 1:0.8. Therefore, a portion where the ratio of the ratio M1 to the ratio M2 satisfies the range of 1:0.3 to 1:0.8 may be a portion where the active layer is actually disposed.

[0224] The ion intensity of the third point P3 may have an ion intensity less than the minimum ion intensity (i.e., the ion intensity of the well layer) in the second portion S2. In this case, the active layer may be included in the second portion S2 and may be defined as a region between the trough P8 closest to the first point P1 and the trough P9 farthest from the first point P1.

[0225] Also, the distance between adjacent valleys S22 may be smaller than the distance between the first point P1 and the second point P2 because the thickness of the well layer and the barrier layer is smaller than the entire thickness of the active layer 126 .

[0226] The first portion S1 may include a surface area S11 having an ion intensity less than that of the fourth point P4. In this case, the ion intensity of the surface area S11 may decrease in a direction opposite to the first direction D.

[0227] According to SIMS data, the ratio (D1:D2) of the first intensity difference D1 between the second point P2 and the fourth point P4 to the second intensity difference D2 between the first point P1 and the third point P3 may be in the range of 1:1.5 to 1:2.5. When the intensity difference ratio D1:D2 is greater than or equal to 1:1.5 (e.g., 1:1.6), the second intensity difference D2 is reduced, and thus the aluminum component of the first point P1 may be sufficiently reduced. Therefore, the contact resistance with the second electrode may be reduced.

[0228] Also, when the intensity difference ratio D1:D2 is less than or equal to 1:2.5 (eg, 1:2.4), light emitted from the active layer 126 can be prevented from being absorbed by the 2-1 conductive semiconductor layer 127a due to low aluminum content, thereby preventing optical characteristics of the semiconductor from being deteriorated.

[0229] A ratio (D3:D4) of the third intensity difference D3 between the seventh point P7 and the first point P1 to the fourth intensity difference D4 between the fourth point P4 and the third point P3 may be in the range of 1:0.2 to 1:2 or 1:0.2 to 1:1.

[0230] When the intensity difference ratio is greater than or equal to 1:0.2, the fourth intensity difference D4 is relatively increased, and thus the aluminum component can be sufficiently reduced. Therefore, the contact resistance with the second electrode can be reduced. In addition, when the composition ratio is less than or equal to 1:2, the crystallinity reduction caused by the rapid change of the aluminum component within the thickness range of the 2-1 conductive semiconductor layer 127a can be prevented. Moreover, the light emitted by the active layer 126 can be prevented from being absorbed by the 2-1 conductive semiconductor layer 127a due to the low aluminum component.

[0231] Typically, a thin GaN layer is inserted for ohmic contact between the second conductive semiconductor layer 127 and the electrode. However, in this case, since the GaN layer in contact with the electrode does not contain aluminum, the aluminum ion intensity at the third point P3 is not measured or significantly reduced. Therefore, the ratio of the first intensity difference D1 to the second intensity difference D2 (D1: D2) and the ratio of the third intensity difference D3 to the fourth intensity difference D4 (D3: D4) may deviate from the above ranges.

[0232] The ratio of the intensity difference between the first point P1 and the third point P3 to the intensity difference between the fifth point P5 and the third point P3 may be in the range of 1:0.5 to 1:0.8. When the intensity difference ratio is greater than or equal to 1:0.5, the intensity of the fifth point P5 increases. Thus, the crystallinity can be improved and the light extraction efficiency can be improved. In addition, when the intensity difference ratio is less than 1:0.8, the lattice mismatch between the active layer 126 and the first conductive semiconductor layer 124 can be mitigated.

[0233] The ion strength ratio (P3:P1) of the third point P3 to the first point P1 may be in the range of 1:2 to 1:4. When the ion strength ratio of the third point P3 to the first point P1 is greater than or equal to 1:2 (e.g., 1:2.1), the strength of the third point P3 is greatly reduced, thereby reducing the contact resistance with the second electrode. In addition, when the ion strength ratio of the third point P3 to the first point P1 is less than or equal to 1:4 (e.g., 1:3.9), the aluminum strength of the third point P3 may be increased. Therefore, light may be prevented from being absorbed at the third point P3.

[0234] The ion intensity ratio of the tenth point P10 to the first point P1 may be in the range of 1:1.3 to 1:2.5. When the ion intensity ratio of the tenth point P10 to the first point P1 is greater than or equal to 1:1.3, the ion intensity of the first point P1 increases, thereby effectively preventing the first carrier from passing through the active layer. When the ion intensity ratio of the tenth point P10 to the first point P1 is less than or equal to 1:2.5, the ion intensity of the tenth point P10 increases, thereby the well layer can generate ultraviolet wavelength light.

[0235] The ion strength ratio of the third point P3 to the fourth point P4 may be in the range of 1:1.1 to 1:2. When the ion strength ratio of the third point P3 to the fourth point P4 is greater than or equal to 1:1.1, the ion strength of the fourth point P4 increases, thereby reducing the absorption rate of ultraviolet wavelength light. In addition, when the ion strength ratio of the third point P3 to the fourth point P4 is less than or equal to 1:2, the ion strength of the third point is fully ensured, thereby reducing the absorption rate of ultraviolet wavelength light.

[0236] The ion intensity ratio of the second point P2 to the first point P1 may be in the range of 1:1.1 to 1:2. When the ion intensity ratio of the second point P2 to the first point P1 is greater than or equal to 1:1.1, the ion intensity of the first point P1 increases, thereby effectively preventing the first carrier from passing through the active layer. In addition, when the ion intensity ratio of the second point P2 to the first point P1 is less than or equal to 1:2, the first carrier and the second carrier injected into the active layer and radiatively recombined with each other may reach a balance in concentration, and the amount of light emitted by the semiconductor device may be enhanced.

[0237] The ion strength ratio of the fourth point P4 to the second point P2 may be in the range of 1:1.2 to 1:2.5. When the ion strength ratio of the fourth point P4 to the second point P2 is greater than or equal to 1:1.2, the resistance between the fourth point P4 and the first electrode may be reduced. In addition, when the ion strength ratio of the fourth point P4 to the second point P2 is less than or equal to 1:2.5, the ion strength of the fourth point P4 increases, thereby reducing the absorption rate of ultraviolet wavelength light.

[0238] The ion intensity ratio of the fifth point P5 to the second point P2 may be in the range of 1:1.1 to 1:2.0. According to an embodiment, compared with a semiconductor structure emitting blue light, a semiconductor structure emitting deep ultraviolet light may be made of a GaN-based material containing a large amount of aluminum. Therefore, the ratio of the mobility of the first carrier to the mobility of the second carrier of the semiconductor structure emitting deep ultraviolet light is different from the ratio of the mobility of the first carrier to the mobility of the second carrier of the semiconductor structure emitting blue light. That is, when the ion intensity ratio of the fifth point P5 to the second point P2 is greater than or equal to 1:1.1, the concentration of the first carrier injected into the active layer can be ensured. In addition, when the ion intensity ratio of the fifth point P5 to the second point P2 is less than or equal to 1:2.0, the ion intensity of the fifth point P5 increases, thereby improving the crystallinity.

[0239] The ionic strength ratio of the fourth point P4 to the fifth point P5 may be in the range of 1:1.1 to 1:2.0. When the ionic strength ratio of the fourth point P4 to the fifth point P5 is greater than or equal to 1:1.1, the ionic strength of the fifth point P5 increases, thereby improving crystallinity. In addition, when the ionic strength ratio of the fourth point P4 to the fifth point P5 is less than or equal to 1:2.0, the ionic strength of the fourth point P4 increases, thereby reducing the absorption rate of ultraviolet wavelength light.

[0240] exist Fig.12 and Fig.13a In the embodiment, the aluminum ion strength is represented by a logarithmic scale. However, the present invention is not limited thereto, and the aluminum ion strength can be represented by a linear scale.

[0241] According to the embodiment, it can be seen that because the third point P3 contains aluminum, the first point P1 and the third point P3 are actually set within a single order of magnitude. The order of magnitude may be a level unit of ion strength. For example, the first order of magnitude may be 1.0×10 1 , the second order of magnitude can be 1.0×10 2 . Furthermore, each order of magnitude can have ten sub-levels.

[0242] For example, the first sub-level of the first order of magnitude may be 1.0×10 1 , the second sub-level of the first order of magnitude can be 2.0×10 1, the third sub-level of the first order of magnitude can be 3.0×10 1 , the ninth sub-level of the first order of magnitude can be 9.0×10 1 , the tenth sub-level of the first order of magnitude may be 1.0×10 2 That is, the tenth sublevel of the first order of magnitude can be equal to the first sublevel of the second order of magnitude. Fig.13b In the figure, the dotted lines represent every two sub-levels.

[0243] Fig.14a is a conceptual view of a second conductive semiconductor layer according to an embodiment of the present invention, Fig.14b shows AFM data obtained by measuring the surface of the second conductive semiconductor layer according to an embodiment of the present invention, Fig.14c shows the AMF data obtained by measuring the surface of a GaN thin film, Fig.14d AFM data obtained by measuring the surface of the second conductive semiconductor layer grown at a high speed are shown.

[0244] See also Fig.14a The second conductive semiconductor layer 127 according to the embodiment may include a 2-1 conductive semiconductor layer 127a, a 2-2 conductive semiconductor layer 127b, and a 2-3 conductive semiconductor layer 127c. The 2-1 conductive semiconductor layer 127a may be a contact layer contacting the second electrode. The above description may be applied to explain the characteristics of these layers.

[0245] The surface of the 2-1 conductive semiconductor layer 127a may include a plurality of clusters C1. Each cluster C1 may be a protrusion protruding from the surface. For example, each cluster C1 may be a protrusion protruding from the average surface height by more than about 10 or 20 nm. Each cluster C1 may be formed due to lattice mismatch between aluminum (Al) and gallium (Ga).

[0246] According to the embodiment, the 2-1 conductive semiconductor layer 127a contains aluminum, and the contained aluminum varies greatly based on thickness, and the 2-1 conductive semiconductor layer 127a is thinner than other layers. Therefore, the 2-1 conductive semiconductor layer 127a is not formed on the surface in the form of a single layer but in the form of clusters C1. Each cluster C1 may contain Al, Ga, N, Mg, etc. However, the present invention is not limited thereto.

[0247] See also Fig.14b , it can be seen that the cluster C1 is formed in the shape of relatively bright dots on the surface of the second conductive semiconductor layer 127. According to the embodiment, the 2-1 conductive semiconductor layer 127a has an aluminum composition of 1% to 10%, and thus the 2-1 conductive semiconductor layer 127a may be formed in the form of cluster C1 to increase the bonding area. Therefore, the electrical characteristics may be enhanced.

[0248] On the surface of the second conductive semiconductor layer 127, every 1 μm 2 One to eight clusters C1 can be observed. Here, the average is the average of multiple values ​​measured at about 10 or more different locations. Fig.14b The result obtained at position E1 was that 12 clusters C1 were observed per unit area (2 μm×2 μm). Only clusters C1 protruding more than 25 nm from the surface were measured. By adjusting the contrast of the AFM image, it was ensured that only clusters protruding more than 25 nm from the surface could be output.

[0249] The density of cluster C1 using the converted units based on the measurement results can be 1×10 -8 / cm 2 Up to 8×10 -6 / cm 2 When the density of cluster C1 is less than 1×10 -8 / cm 2 When the contact area is relatively reduced, the contact resistance with the second electrode can be increased.

[0250] In addition, when the density of cluster C1 is greater than 8×10 -6 / cm 2 When , light emitted from the active layer 126 is absorbed by Ga contained in some clusters, so that the light output power can be reduced.

[0251] According to an embodiment, the density of cluster C1 may satisfy 1×10 -8 / cm 2 Up to 8×10 -6 / cm 2 Therefore, the contact resistance with the second electrode can be reduced without reducing the light output power.

[0252] See also Fig.14c , it can be seen that no clusters are observed from the surface of the GaN film. This is because the GaN film is formed as a single layer as the density of the clusters increases. Therefore, it can be seen that when the GaN film is formed between the second conductive semiconductor layer and the second electrode, no clusters are formed on the contact surface.

[0253] See also Fig.14d , it can be seen that when the second conductive semiconductor layer grows at a high speed, the clusters fail to grow well. Therefore, it can be seen that when the second conductive semiconductor layer grows at a high speed, although the aluminum component of the second conductive semiconductor layer is controlled to be in the range of 1% to 10% on its surface, the cluster C1 is still not formed. For example, Fig.14d This is a photograph obtained by measuring the surface after growing P-AlGaN at a rate of 0.06 nm / s.

[0254] That is, it can be seen that the surface layer should have an aluminum composition of 1% to 10% and also have a very low growth rate in order to form a plurality of clusters C1 in the second conductive semiconductor layer 127 .

[0255] According to an embodiment, the 2-1 conductive semiconductor layer may have a lower growth rate than the 2-2 conductive semiconductor layer and the 2-3 conductive semiconductor layer. For example, the growth rate ratio of the 2-2 conductive semiconductor layer to the 2-1 conductive semiconductor layer may be in the range of 1:0.2 to 1:0.8. When the growth rate ratio is less than 1:0.2, the growth rate of the 2-1 conductive semiconductor layer is very low, so that AlGaN with a high aluminum content can be grown by etching Ga at a high temperature for growing AlGaN, thereby reducing its ohmic characteristics. When the growth rate ratio is greater than 1:0.8, the growth rate of the 2-1 conductive semiconductor layer is very high, thereby reducing the crystallinity.

[0256] Fig.15 is a conceptual view of a semiconductor device according to an embodiment of the present invention, Fig.16a and Fig.16b is a diagram showing a configuration in which light output power is enhanced as the number of grooves is varied, Fig.17 yes Fig.15 Magnified view of part A.

[0257] See also Fig.15 According to the embodiment, the semiconductor device may include a semiconductor structure 120 (the semiconductor structure 120 includes a first conductive semiconductor layer 124, a second conductive semiconductor layer 127 and an active layer 126), a first electrode 142 and a second electrode 146, the first electrode 142 is electrically connected to the first conductive semiconductor layer 124, and the second electrode 146 is electrically connected to the second conductive semiconductor layer 127.

[0258] The first conductive semiconductor layer 124, the active layer 126, and the second conductive semiconductor layer 127 may be disposed along a first direction (ie, a Y direction). Here, the first direction (ie, a Y direction) as a thickness direction of each layer is defined as a vertical direction, and a second direction (ie, a X direction) perpendicular to the first direction (ie, a Y direction) is defined as a horizontal direction.

[0259] All of the above structures may be applied to the semiconductor structure 120 according to the embodiment. The semiconductor structure 120 may include a plurality of grooves 128 provided in a portion of the first conductive semiconductor layer 124 even through the second conductive semiconductor layer 127 and the active layer 126 .

[0260] The first electrode 142 may be disposed on the top of the groove 128 and electrically connected to the first conductive semiconductor layer 124. The second electrode 146 may be formed under the second conductive semiconductor layer 127.

[0261] Each of the first electrode 142 and the second electrode 146 may be an ohmic electrode. Each of the first electrode 142 and the second electrode 146 may be made of at least one of the following: 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), IZO nitride (IZON), Al-Ga ZnO (AGZO), In-Ga ZnO (IGZO), ZnO, IrO x 、RuO x 、NiO、RuO x / ITO、Ni / IrO x / Au、Ni / IrO x / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, and Hf, but not limited thereto. For example, the first electrode may have a plurality of metal layers (e.g., Cr, Al, and Ni), and the second electrode may be made of ITO.

[0262] See also Fig.16a , when the GaN-based semiconductor structure 120 emits ultraviolet light, the GaN-based semiconductor structure 120 may include aluminum. When the aluminum component of the semiconductor structure 120 increases, the current diffusion characteristics in the semiconductor structure 120 may be reduced. Moreover, compared with a GaN-based blue light emitting device (TM mode), when the active layer 126 includes aluminum and emits ultraviolet light, the active layer 126 may have an increased amount of light emitted to the side. The TM mode may mainly occur in an ultraviolet semiconductor device.

[0263] The ultraviolet semiconductor device has a reduced current spreading characteristic compared to the blue GaN-based 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-based semiconductor device.

[0264] When the aluminum content increases, the current spreading characteristics may deteriorate. Fig.16a , the current spreads only at a point adjacent to each first electrode 142, and the current density may be rapidly reduced at a point away from each first electrode 142. Therefore, the effective light emitting area P2 may be narrowed.

[0265] The region up to such a boundary, where the current density is 40% or less of the first electrode 142 having the highest current density, can be defined as the effective light emitting region P2. For example, the effective light emitting region P2 can be adjusted within a range of less than 40 μm from the center of each groove 128 depending on the injected current level and the aluminum composition.

[0266] The current density of the low current density region P3 may be lower than that of the effective light emitting region P2, and thus, the amount of light in the low current density region P3 is less than that in the effective light emitting region P2. Therefore, the light output power may be enhanced by disposing a large number of first electrodes 142 in the low current density region P3 having a low current density or by using a reflective structure.

[0267] Generally, since the GaN semiconductor layer emitting blue light has a relatively excellent current diffusion characteristic, it is preferred to minimize the area of ​​the groove 128 and the first electrode 142. This is because as the area of ​​the groove 128 and the first electrode 142 increases, the area of ​​the active layer 126 decreases. However, according to the embodiment, because the aluminum component is high, the current diffusion characteristic is relatively low. Therefore, it is preferred to reduce the low current density region P3 by increasing the area and / or number of the first electrode 142 (although the area of ​​the active layer 126 is reduced in this way) or preferably set the reflective structure in the low current density region P3.

[0268] See also Fig.16b When the number of the grooves 128 increases to 48, the grooves 128 may be arranged in a zigzag form rather than being arranged straightly in the horizontal or vertical direction. In this case, the area of ​​the low current density region C3 may be reduced, so that most of the active layer 126 may participate in light emission.

[0269] The ultraviolet light emitting device may have a reduced current diffusion characteristic in the semiconductor structure 120. Thus, a smooth injection of current is required to ensure a uniform current density characteristic in the semiconductor structure 120 and to ensure electrical and optical characteristics and reliability of the semiconductor device. Therefore, in order to smoothly inject current, a relatively large number of grooves 128 may be formed compared to the GaN-based semiconductor structure 120, and then the first electrode 142 may be disposed on the groove 128.

[0270] See also Fig.17 , 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 electrode 146 and the second conductive layer 150 from the first conductive layer 165. In addition, the first insulating layer 131 may be used to prevent side oxidation of the active layer 126 during the process of the semiconductor device.

[0271] 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, but is not limited thereto. 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.

[0272] When the first insulating layer 131 has a reflective function, the first insulating layer 131 may reflect light horizontally emitted from the active layer 126 upward, thereby enhancing light extraction efficiency. In this case, as the number of grooves 128 increases, light extraction efficiency may be improved.

[0273] The diameter W3 of the first electrode 142 may be 24 μm to 50 μm. When this range is satisfied, it is advantageous in terms of diffusion current, and a large number of first electrodes 142 may be provided. When the diameter W3 of the first electrode 142 is greater than or equal to 24 μm, the current injected into the first conductive semiconductor layer 124 may be sufficiently ensured. When the diameter W3 of the first electrode 142 is less than or equal to 50 μm, the number of first electrodes 142 provided in the region of the first conductive semiconductor layer 124 may be sufficiently ensured, and current diffusion characteristics may also be ensured.

[0274] The diameter W1 of each groove 128 may be 38 μm to 60 μm. The diameter W1 of each groove 128 may be defined as the maximum area of ​​the groove disposed under the second conductive semiconductor layer 127. The diameter W1 of each groove 128 may be the diameter of the groove disposed at the bottom surface of the second conductive semiconductor layer 127.

[0275] When the diameter W1 of each groove 128 is greater than or equal to 38 μm, a process margin of a region where the first electrode 142 is electrically connected to the first conductive semiconductor layer 124 may be secured when the first electrode 142 to be disposed inside each groove 128 is formed. When the diameter W1 of each groove 128 is less than or equal to 60 μm, a reduction in the volume of the active layer 126 may be prevented in order to dispose the first electrode 142, and thus light emission efficiency may be deteriorated.

[0276] The slope angle θ5 of each groove 128 may be 70 degrees to 90 degrees. When this range is satisfied, it is advantageous to form the first electrode 142 at the top of the groove 128, and a large number of grooves 128 may be formed.

[0277] When the slope angle θ5 is less than 70 degrees, the removal area of ​​the active layer 126 can be increased, but the area where the first electrode 142 is to be disposed can be reduced. Therefore, the current injection characteristics and the light emitting efficiency can be reduced. Therefore, the area ratio of the first electrode 142 to the second electrode 146 can be adjusted by using the slope angle θ5 of each groove 128.

[0278] The second electrode 146 may be thinner than the first insulating layer 131. Therefore, the step coverage characteristics of the second conductive layer 150 and the second insulating layer 132 surrounding the second electrode 146 can be ensured and the reliability of the semiconductor device can be improved. The second electrode 146 may be set to be spaced apart from the first insulating layer 131 by a first spacing distance S1 of about 1 μm to 4 μm. When the spacing distance is greater than or equal to 1 μm, the process margin of setting the second electrode 146 relative to the first insulating layer 131 can be ensured, thereby improving the electrical characteristics, optical characteristics and reliability of the semiconductor device. When the spacing distance is less than or equal to 4 μm, the entire area where the second electrode 146 can be arranged can be ensured, and the operating voltage characteristics of the semiconductor device can be improved.

[0279] The second conductive layer 150 may cover the second electrode 146. Therefore, the second electrode pad 166, the second conductive layer 150, and the second electrode 146 may form one electrical channel.

[0280] The second conductive layer 150 may completely surround the second electrode 146 and may be in contact with one side surface and the upper surface of the first insulating layer 131. The second conductive layer 150 may be made of a material having good adhesion to the first insulating layer 131 and made of at least one material selected from a group of materials including Cr, Al, Ti, Ni, and Au or alloys thereof. Also, the second conductive layer 150 may be formed as a single layer or multiple layers.

[0281] When the second conductive layer 150 is in contact with the side surface and the bottom surface of the first insulating layer 131, the thermal reliability and electrical reliability of the second electrode 146 can be enhanced. The second conductive layer 150 may extend to the lower portion of the first insulating layer 131. In this case, the detachment of the end of the first insulating layer 131 can be suppressed. Therefore, the penetration of external moisture or contaminants can be prevented. In addition, the second conductive layer 150 may have a reflective function for reflecting light emitted from the gap between the first insulating layer 131 and the second electrode 146 upward.

[0282] The second conductive layer 150 may be disposed at a first spacing distance S1 between the first insulating layer 131 and the second electrode 146. That is, the second conductive layer 150 may be disposed at the first spacing distance S1 and in contact with one side surface and an upper surface of the second electrode 146 and one side surface and an upper surface of the first insulating layer 131. In addition, a region may be disposed within the first spacing distance S1, in which the second conductive semiconductor layer 126 contacts the second conductive layer 150 to form a Schottky junction. By forming a Schottky junction, current distribution may be facilitated. However, the present invention is not limited thereto, and may be freely arranged as long as the resistance between the second electrode 146 and the second conductive semiconductor layer 127 is greater than the resistance between the second conductive layer 150 and the second conductive semiconductor layer 127.

[0283] The second insulating layer 132 may electrically insulate the second electrode 146 and 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 via the second insulating layer 132. The second insulating layer 132 and the first insulating layer 131 may be made of the same material or different materials.

[0284] According to an embodiment, the second insulating layer 132 is disposed between the first electrode 142 and the second electrode 146 and over the first insulating layer 131 , and thus, even if a defect occurs in the first insulating layer 131 , penetration of external moisture and / or other contaminants may be prevented.

[0285] For example, when the first insulating layer 131 and the second insulating layer 132 are formed as a single layer, defects such as cracks are easily propagated in the thickness direction. Therefore, external moisture or contaminants may penetrate into the semiconductor structure through the exposed defects.

[0286] However, according to the embodiment, the second insulating layer 132 is separately provided over the first insulating layer 131, thus making it difficult for defects formed in the first insulating layer 131 to propagate to the second insulating layer 132. That is, the interface between the first insulating layer 131 and the second insulating layer 132 serves to block the propagation of defects.

[0287] See again Fig.15 , the second conductive layer 150 can electrically connect the second electrode to the second electrode pad 166 .

[0288] The second electrode 146 may be directly disposed on the second conductive semiconductor layer 127. When the second conductive semiconductor layer 127 is made of AlGaN, holes may not be smoothly injected because of low conductivity. Therefore, it is necessary to properly adjust the aluminum composition of the second conductive semiconductor layer 127. This will be described later.

[0289] The second conductive layer 150 may be made of at least one material selected from a group consisting of Cr, Al, Ti, Ni, and Au or alloys thereof. Also, the second conductive layer 150 may be formed as a single layer or multiple layers.

[0290] The first conductive layer 165 and the bonding layer 160 may be arranged according to the bottom surface of the semiconductor structure 120 and the shape of the groove 128. The first conductive layer 165 may be made of a high-quality reflective material. 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 the light emitted by the active layer 126 upward in the direction toward the substrate, thereby improving the light extraction efficiency. However, the present invention is not limited thereto, and the first conductive layer 165 may provide a function of being electrically connected to the first electrode 142. The first conductive layer 165 may not include a highly reflective material, such as aluminum and / or silver (Ag). In this case, a reflective metal layer (not shown) containing a highly reflective material may be arranged between the first conductive layer 165 and the first electrode 142 arranged in the groove 128 and between the second conductive semiconductor layer 127 and the first conductive layer 165.

[0291] The bonding layer 160 may include a conductive material. For example, the bonding layer 160 may include a material selected from a group of materials, the group of materials including gold, tin, indium, aluminum, silicon, silver, nickel and copper or alloys thereof.

[0292] The substrate 170 may be made of a conductive material. For example, the substrate 170 may include a metal or a semiconductor material. For example, the substrate 170 may be made of a metal having excellent electrical conductivity and / or thermal conductivity. In this case, the heat generated when the semiconductor device is working can be quickly released to the outside. Moreover, when the substrate 170 is made of a conductive material, the first electrode 142 can receive a current provided from an external source through the substrate 170.

[0293] The substrate 170 may include a material selected from the group consisting of silicon, molybdenum, tungsten, copper, and aluminum or alloys thereof.

[0294] The passivation layer 180 may be disposed on the upper surface and one side surface of the semiconductor structure 120. The thickness of the passivation layer 180 may be 200 nm to 500 nm. When the thickness is greater than or equal to 200 nm, the device may be protected from external moisture or foreign materials, thereby improving electrical and optical reliability. When the thickness is less than or equal to 500 nm, the stress applied to the semiconductor device may be reduced, and an increase in semiconductor cost due to reduced optical and electrical reliability of the semiconductor device or extended processing time of the semiconductor device may also be prevented.

[0295] A square wave pattern may be formed on the upper surface of the semiconductor structure 120. The square wave pattern may improve the extraction efficiency of light emitted from the semiconductor structure 120. The square wave pattern may have different average heights depending on the wavelength of ultraviolet light, and the average height of UV-C light is 300nm to 800nm. When the average height is 500nm to 600nm, the light extraction efficiency may be improved.

[0296] Fig.18 is a conceptual view of a semiconductor device according to another embodiment of the present invention, Fig.19 yes Fig.18 Floor plan.

[0297] See also Fig.18 , the above structure may be similarly applied to the semiconductor structure 120 . Also, a plurality of grooves 128 may be provided in a portion of the first conductive semiconductor layer 124 through the second conductive semiconductor layer 127 and the active layer 126 .

[0298] The semiconductor device may include a side reflector Z1 disposed on an edge thereof. The side reflector Z1 may be formed by the second conductive layer 150, the first conductive layer 165, and the substrate 170 protruding in the thickness direction (Y-axis direction). Fig. 20 , the side reflector Z1 may be disposed along an edge of the semiconductor device to surround the semiconductor structure 120 .

[0299] The second conductive layer 150 of the side reflector Z1 protrudes farther than the active layer 126, so that the second conductive layer 150 can upwardly reflect light emitted from the active layer 126. Therefore, without forming a separate reflective layer, light emitted in a horizontal direction (X-axis direction) can be reflected upward at its outermost portion due to the TM mode.

[0300] The slope angle of the side reflector Z1 may be greater than 90 degrees and less than 145 degrees. The slope angle may be the angle of the second conductive layer 150 relative to the horizontal plane (ie, the XZ plane). When the angle is less than 90 degrees or greater than 145 degrees, the efficiency of upward reflection of light traveling toward the side may be reduced.

[0301] Fig. 20 is a conceptual view of a semiconductor device package according to an embodiment of the present invention, Fig.21 is a plan view of a semiconductor device package according to an embodiment of the present invention, Fig. 22 yes Fig.21 A variation of Fig.23 is a cross-sectional view of a semiconductor device package according to another embodiment of the present invention.

[0302] See also Fig. 20, a semiconductor device package may include: a body 2 having a groove (ie, an opening) 3; a semiconductor device 1 disposed in the body 2; and a pair of lead frames 5a and 5b disposed in the body 2 and electrically connected to the semiconductor device 1. The semiconductor device 1 may include all of the above elements.

[0303] The body 2 may include an ultraviolet reflective material or a coating layer. The body 2 may be formed by stacking a plurality of layers 2a, 2b, 2c, 2d, and 2e. The plurality of layers 2a, 2b, 2c, 2d, and 2e may be made of the same material or may include different materials. For example, the plurality of layers 2a, 2b, 2c, 2d, and 2e may include aluminum.

[0304] The groove 3 may have a width that increases as it moves away from the semiconductor device, and have an inclined surface in which a step portion 3 a is formed.

[0305] 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. There is no limitation on the material of the light-transmitting layer 4 as long as the material can effectively transmit ultraviolet light. The space formed in the groove 3 may be empty.

[0306] See also Fig.21 , 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 5a.

[0307] See also Fig. 22 , a plurality of semiconductor devices 10a, 10b, 10c and 10d may be provided in the semiconductor device package. 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.

[0308] The first semiconductor device 10a can be arranged on the first lead frame 5a and connected to the second lead frame 5b through a wire. The second semiconductor device 10b can be arranged on the second lead frame 5b and connected to the third lead frame 5c through a wire. The third semiconductor device 10c can be arranged on the third lead frame 5c and connected to the fourth lead frame 5d through a wire. The fourth semiconductor device 10d can be arranged on the fourth lead frame 5d and connected to the fifth lead frame 5e through a wire.

[0309] See also Fig.23 The semiconductor device package may include: a body 10 including a cavity 11 ; a semiconductor device 100 disposed inside the cavity 11 ; and a light-transmitting member 50 disposed on the cavity 11 .

[0310] The main body 10 can be manufactured by processing an aluminum substrate. Therefore, the main body 10 according to the embodiment can have an inner surface and an outer surface that are both conductive. This structure has various advantages. When non-conductive materials such as AlN and Al2O3 are used for the main body 10, the reflectivity of the ultraviolet wavelength band is only 20% to 40%. Therefore, it is necessary to set a separate reflective member. Moreover, a separate circuit pattern and a conductive member such as a lead frame may be required. Therefore, the production cost may be increased and the process may be complicated. Moreover, conductive members such as gold (Au) absorb ultraviolet light, so the light extraction efficiency is reduced.

[0311] However, according to the embodiment, the main body 10 itself is made of aluminum, and thus, due to high reflectivity in the ultraviolet wavelength band, a separate reflective member can be omitted. Moreover, the main body 10 itself is conductive, and thus a separate circuit pattern and lead frame can be omitted. Moreover, since the main body 10 is made of aluminum, the excellent thermal conductivity of the main body 10 can be 140W / m·k to 160W / m·k. Therefore, the heat dissipation efficiency can be improved.

[0312] The body 10 may include a first conductive component 10a and a second conductive component 10b. A first insulating component 42 may be disposed between the first conductive component 10a and the second conductive component 10b. Since both the first conductive component 10a and the second conductive component 10b are conductive, the first insulating component 42 is required to separate the magnetic poles.

[0313] The body 10 may include a groove 14 disposed at an edge between the lower surface 12 and the side surface 13, and a second insulating member 41 disposed on the groove 14. The groove 14 may be disposed along an edge between the lower surface 12 and the side surface 13.

[0314] The second insulating member 41 may be made of the same material as the first insulating member 42, but is not limited thereto. Each of the first insulating member 42 and the second insulating member 41 may be made of one material selected from the following materials: epoxy molding compound (EMC), white silicon, photoimageable solder resist (PSR), silicone resin composition, modified epoxy resin composition (such as silicon-modified epoxy resin), modified silicone resin composition (such as epoxy-modified silicone resin), polyimide resin composition, modified polyimide resin composition, polyphthalamide (PPA), polycarbonate resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), acrylonitrile butadiene styrene (ABS) resin, phenolic resin, acrylic resin, and polybutylene terephthalate PBT resin.

[0315] According to one embodiment, the second insulating member 41 is disposed at the lower edge of the body 10, thereby preventing burrs from appearing at the edge when the package is cut. Burrs may appear more frequently on aluminum substrates than on other metal substrates. When burrs appear, the lower surface 12 may be uneven, making it difficult to mount well. In addition, when burrs appear, the thickness may become uneven and measurement errors may occur.

[0316] The third insulating member 43 may be disposed on the lower surface 12 of the body 10 and connected to the second insulating member 41 and the first insulating member 42. According to one embodiment, the lower surface 12 of the body 10, the lower surface of the second insulating member 41, and the lower surface of the third insulating member 43 may be disposed on the same plane.

[0317] Fig.24 is a conceptual view of a light emitting structure according to an embodiment of the present invention, Fig.25 is a graph illustrating aluminum composition of a semiconductor structure according to an embodiment of the present invention.

[0318] See also Fig.24 The semiconductor device according to the embodiment includes a light emitting structure 120A, and the light emitting structure 120A includes a first conductive semiconductor layer 124, a second conductive semiconductor layer 127 and an active layer 126. Each semiconductor layer may have a Figure 1 The structure is the same as described.

[0319] See also Fig.25 , the first conductive semiconductor layer 124, the active layer 126, the barrier layer 129, and the second conductive semiconductor layer 127 may all contain aluminum.

[0320] Therefore, the first conductive semiconductor layer 124, the active layer 126, the barrier layer 129, and the second conductive semiconductor 127 may be made of AlGaN. However, the present invention is not limited thereto. Some layers may be made of GaN or AlN.

[0321] The active layer 126 may include a plurality of well layers 126a and a plurality of barrier layers 126b disposed alternately. Each well layer 126a may have an aluminum composition of about 30% to about 50% to emit ultraviolet light. Each barrier layer 126b may have an aluminum composition of 50% to 70% to capture carriers.

[0322] For example, a well layer closest to the barrier layer 129 among the well layers 126 a is defined as a first well layer 126 a , and a last barrier layer disposed between the first well layer 126 a and the barrier layer 129 is defined as a first barrier layer 126 b .

[0323] The barrier layer 129 may have an aluminum composition of 50% to 90%. The barrier layer 129 may have a plurality of first barrier layers 129d having a higher aluminum composition and a plurality of second layers 129a having a lower aluminum composition, which are alternately arranged in the barrier layer 129. When the aluminum composition of the barrier layer 129 is less than 50%, the energy barrier for blocking electrons may not be high enough, and the barrier layer 129 may absorb light emitted from the active layer 126. When the aluminum composition of the barrier layer 129 is greater than 90%, the electrical characteristics of the semiconductor device may be reduced.

[0324] Each first barrier layer 129d may have an aluminum composition of 70% to 90%, and each second barrier layer 129e may have an aluminum composition of 50% to 70%. However, the present invention is not limited thereto, and the aluminum composition of each first barrier layer 129d and each second barrier layer 129e may be appropriately adjusted.

[0325] The first intermediate layer S10 may be disposed between the barrier layer 129 and the first well layer 126a of the active layer 126. The first intermediate layer S10 may include a 3-1 portion S11 having an aluminum composition lower than that of the barrier layer 129 and a 3-2 portion S12 having an aluminum composition higher than that of the barrier layer 129.

[0326] The first intermediate layer S10 may be a first barrier layer 126b. Therefore, the thickness of the first intermediate layer S10 may be the same as the thickness of the adjacent barrier layer 126b. For example, the thickness of the first intermediate layer S10 may be 2nm to 10nm. However, the present invention is not limited thereto, and the first intermediate layer S10 may be a part of the barrier layer 129 or a separate semiconductor layer disposed between the first barrier layer 126b and the barrier layer.

[0327] The 3-1 portion S11 may have an aluminum composition of 50% to 70%. That is, the aluminum composition of the 3-1 portion S11 may be substantially the same as the aluminum composition of the adjacent barrier layer 126b. The thickness of the 3-1 portion S11 may be from about 1nm to about 8nm. When the thickness of the 3-1 portion is less than or equal to 1nm, the aluminum composition of the well layer 126a increases rapidly, and thus it may be difficult to prevent the crystallinity from decreasing. Moreover, when the thickness of the 3-1 portion S11 is greater than 8nm, the injection efficiency of the holes injected into the active layer 126 may be reduced, thereby reducing the optical characteristics.

[0328] The aluminum composition of the 3-2 portion S12 may be higher than that of the barrier layer 129. The aluminum composition of the 3-2 portion S12 may increase toward the barrier layer 129. The aluminum composition of the 3-2 portion S12 may be in the range of 80% to 100%. That is, the 3-2 portion S12 may be made of AlGaN or AlN. Alternatively, the 3-2 portion S12 may be a superlattice layer in which AlGaN and AlN are alternately arranged.

[0329] The 3-2 portion S12 may be thinner than the 3-1 portion S11. The thickness of the 3-2 portion S12 may be about 0.1 nm to about 4 nm. When the thickness of the 3-2 portion S12 is less than 0.1 nm, electron movement may not be blocked. When the thickness of the 3-2 portion S12 is greater than 4 nm, the efficiency of injecting holes into the active layer may be reduced.

[0330] The thickness ratio of the 3-1 portion S11 to the 3-2 portion S12 may be 10: 1 to 1: 1. When this condition is satisfied, hole injection efficiency may be reduced while blocking electron movement.

[0331] The 3-2 portion S12 may include an undoped portion. Although the 3-2 portion S12 is grown without providing a dopant, Mg of the barrier layer 129 may diffuse into a portion of the first portion. However, in order to prevent the dopant from diffusing into the active layer 126, at least some regions of the 3-2 portion S12 may include an undoped portion.

[0332] Fig.26 is a graph showing the aluminum composition of a light emitting structure according to another embodiment of the present invention, Fig. 27 is a graph obtained by measuring the light output power of a semiconductor device including a conventional light emitting structure, Fig.28 is a graph obtained by measuring the light output power of a light emitting structure according to another embodiment of the present invention.

[0333] See also Fig.26 , except for the second intermediate layer S20, the same as already mentioned can be applied Fig.25 The second intermediate layer S20 may be a part of the barrier layer 129, but is not limited thereto.

[0334] The aluminum composition of the second intermediate layer S20 may be lower than that of the barrier layer 129 but higher than that of the 3-1 portion S11. For example, the aluminum composition of the second intermediate layer S20 may be in the range of 50% to 80%.

[0335] The second intermediate layer S20 may include a 4-1 portion S21 not containing a p-type dopant and a 4-2 portion S22 containing a p-type dopant.

[0336] The 4-1 portion S21 may include an undoped portion. Therefore, diffusion of dopants to the active layer 126 may be suppressed when the barrier layer 129 grows. The thickness of the 4-1 portion S21 may be 4 nm to 19 nm. When the thickness of the 4-1 portion S21 is less than 4 nm, diffusion of dopants may be suppressed. When the thickness of the 4-1 portion S21 is greater than 19 nm, hole injection efficiency may be reduced.

[0337] The 4-2 portion S22 may contain a p-type dopant. The 4-2 portion S22 contains the dopant and may improve the efficiency of injecting holes into the 4-1 portion S21. That is, the 4-2 portion S22 may be used as a low resistance layer that reduces the resistance level.

[0338] The thickness of the 4-2 portion S22 may be 1 nm to 6 nm. When the thickness is less than 1 nm, it is difficult to effectively reduce the resistance. When the thickness is greater than 6 nm, the thickness of the 4-1 portion S21 is reduced, and it may be difficult to suppress the diffusion of dopants. The ratio of the thickness of the 4-1 portion S21 to the thickness of the 4-2 portion S22 may be in the range of 19:1 to 1:1.5.

[0339] However, the present invention is not limited thereto, and the second intermediate layer S20 may have a super lattice structure in which the 4-1 portion S21 and the 4-2 portion S22 are alternately disposed.

[0340] See also Fig. 27 It can be seen that the light output power of the semiconductor device with the conventional light emitting structure decreases by 20% after about 100 hours. Moreover, it can be seen that the light output power decreases by 25% after about 500 hours.

[0341] On the other hand, see Fig.28 It can be seen that the semiconductor device having the light emitting structure according to the embodiment has a light intensity reduced by about 3.5% after 100 hours, and has almost the same light output power even after about 500 hours. That is, it can be seen that, compared with the conventional structure, without the intermediate layer according to the embodiment, the light output power is increased by about 20%.

[0342] Fig.29 is a graph showing the aluminum composition of a light emitting structure according to still another embodiment of the present invention.

[0343] See also Fig.29 , the second conductive semiconductor layer 129 may include a 2-1 conductive semiconductor layer 129a and a 2-2 conductive semiconductor layer 129b.

[0344] The thickness of the 2-1 conductive semiconductor layer 127a may be 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, the resistance increases in the horizontal direction, thereby reducing the current injection efficiency. When the thickness of the 2-1 conductive semiconductor layer 127a is greater than 200 nm, the resistance increases in the vertical direction, thereby reducing the current injection efficiency.

[0345] The aluminum composition of the 2-1 conductive semiconductor layer 127a may be lower than that of the well layer 126a. In order to generate ultraviolet light, the aluminum composition of the well layer 126a may be about 30% to about 50%. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is lower than that of the well layer 126a, the 2-1 conductive semiconductor layer 127a absorbs light, and thus light extraction efficiency may be reduced.

[0346] The 2-1 conductive semiconductor layer 127a may have an aluminum composition greater than 40% and less than 80%. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is less than 40%, light may be absorbed. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is greater than 80%, current injection efficiency may decrease. For example, when the aluminum composition of the well layer 126a is equal to 30%, the aluminum composition of the 2-1 conductive semiconductor layer 127a may be equal to 40%.

[0347] The aluminum composition of the 2-2 conductive semiconductor layer 127a may be lower than that of the well layer 126a. When the aluminum composition of the 2-2 conductive semiconductor layer 127a is higher than that of the well layer 126a, the 2-2 conductive semiconductor layer 127a and the p-ohmic electrode cannot be sufficiently ohmically contacted due to the increased resistance therebetween, and current injection efficiency may also be reduced.

[0348] The aluminum composition of the 2-2 conductive semiconductor layer 127a may be greater than 1% and less than 50%. When the aluminum composition is greater than 50%, the 2-2 conductive semiconductor layer 127a may not be able to make sufficient ohmic contact with the p-ohmic electrode. When the aluminum composition is less than 1%, the composition of the 2-2 conductive semiconductor layer 127a may be close to GaN, thus absorbing light.

[0349] The thickness of the 2-2 conductive semiconductor layer 127a may be greater than about 1 nm and less than about 30 nm. As described above, the aluminum content contained in the 2-2 conductive semiconductor layer 127a is so low that it can be ohmic and thus absorb ultraviolet light. Therefore, in terms of light output power, it may be advantageous to adjust the 2-2 conductive semiconductor layer 127a to be as thin as possible.

[0350] However, when the thickness of the 2-2 conductive semiconductor layer 127a is controlled to be 1 nm or less, the 2-2 conductive semiconductor layer 127a may not be provided in some portions, and there may be a region in which the 2-1 conductive semiconductor layer 127a is exposed to the outside of the light emitting structure 120. In addition, when the thickness is greater than 30 nm, the amount of absorbed light is so large that light output power efficiency may be reduced.

[0351] The 2-2 conductive semiconductor layer 127a may further include a first sublayer 127e and a second sublayer 127d. The first sublayer 127e may be a surface layer in contact with the second electrode, and the second sublayer 127d may be a layer for adjusting aluminum composition.

[0352] The first sub-layer 127e may have an aluminum composition greater than 1% and less than 20%. Alternatively, the aluminum composition may be greater than 1% and less than 10%.

[0353] When the aluminum composition is less than 1%, the first sublayer 127e may have a high light absorption rate. When the aluminum composition is greater than 20%, the contact resistance of the second electrode (ie, p-ohmic electrode) increases, and thus current injection efficiency may be reduced.

[0354] However, the present invention is not limited thereto, and the aluminum composition of the first sublayer 127e may be adjusted based on current injection characteristics and light absorption rate. Alternatively, the aluminum composition may be adjusted according to the optical output power required by the product.

[0355] For example, when the current injection characteristic is more important than the light absorption rate, the aluminum composition can be adjusted to be in the range of 1% to 10%. When the light output power characteristic is more important than the electrical characteristics of the product, the aluminum composition of the first sublayer 127e can be adjusted to be in the range of 1% to 20%.

[0356] When the aluminum content of the first sublayer 127e is greater than 1% and less than 20%, the operating voltage can be reduced due to the reduced resistance between the first sublayer 127e and the second electrode. Therefore, the electrical characteristics can be enhanced. The thickness of the first sublayer 127e can be greater than 1nm and less than 10nm. Therefore, the light absorption problem can be alleviated.

[0357] The thickness of the 2-2 conductive semiconductor layer 127a may be smaller than the thickness of the 2-1 conductive semiconductor layer 127a. The thickness ratio of the 2-1 conductive semiconductor layer 127a to the 2-2 conductive semiconductor layer 127a may be in the range of 1.5:1 to 20:1. When the thickness ratio is less than 1.5:1, the 2-1 conductive semiconductor layer 127a is too thin, so that the current injection efficiency may be reduced. When the thickness ratio is greater than 20:1, the 2-2 conductive semiconductor layer 127a is too thin, so that the ohmic reliability may be reduced.

[0358] The aluminum composition of the 2-1 conductive semiconductor layer 127a may decrease as being away from the active layer 126. Also, the aluminum composition of the 2-2 conductive semiconductor layer 127a may decrease as being away from the active layer 126. Therefore, the aluminum composition of the first sublayer 127e may satisfy the range of 1% to 10%.

[0359] However, the present invention is not limited thereto, and the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127a may include portions in which the aluminum composition of the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127a is not reduced, rather than the aluminum composition continuously reducing.

[0360] In this case, the degree of reduction of the aluminum composition of the 2-2 conductive semiconductor layer 127a may be greater than the degree of reduction of the aluminum composition of the 2-1 conductive semiconductor layer 127a. That is, the change in the aluminum composition of the 2-2 conductive semiconductor layer 127a in the thickness direction may be greater than the change in the aluminum composition of the 2-1 conductive semiconductor layer 127a in the thickness direction. 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.

[0361] The thickness of the 2-1 conductive semiconductor layer 127a is greater than that of the 2-2 conductive semiconductor layer 127a and the aluminum composition is higher than that of the well layer 126a. Therefore, the aluminum composition of the 2-1 conductive semiconductor layer 127a may be reduced relatively slowly.

[0362] However, the thickness of the 2-2 conductive semiconductor layer 127a is small, and the change of the aluminum content is large. Therefore, the reduction degree of the aluminum content of the 2-2 conductive semiconductor layer 127a is relatively high.

[0363] Fig.30 is a conceptual view of a light-emitting structure grown on a substrate. Fig.31 is a diagram showing a substrate separation process, Fig.32 is a diagram showing a process of etching a light emitting structure, and Fig.33 2 is a diagram showing a manufactured semiconductor device.

[0364] See also Fig.30 The buffer layer 122 , the light absorbing layer 123 , the first conductive semiconductor layer 124 , the active layer 126 , the second conductive semiconductor layer 127 , the second electrode 246 , and the second conductive layer 150 may be sequentially formed on the growth substrate 121 .

[0365] In this case, the first intermediate layer and the second intermediate layer may be grown between the active layer 126 and the barrier layer 129. The first barrier layer may be grown to have a 1-1 portion having an aluminum composition of 50% to 70% and a 1-2 portion having an aluminum composition of 80% to 100%. Also, the second intermediate layer may be grown to have a 2-1 portion not doped with a p-type dopant and a 2-2 portion doped with a dopant.

[0366] The light absorbing layer 123 includes a first light absorbing layer 123a having a low aluminum content and a second light absorbing layer 123b having a high aluminum content. A plurality of first light absorbing layers 123a and a plurality of second light absorbing layers 123b may be alternately disposed.

[0367] The aluminum composition of the first light absorbing layer 123a may be lower than that of the first conductive semiconductor layer 124. The first light absorbing layer 123a may be separated when absorbing laser light during a laser lift-off (LLO) process. Thus, the growth substrate may be removed.

[0368] The thickness and aluminum composition of the first light absorbing layer 123a may be appropriately adjusted to absorb laser light of a predetermined wavelength (e.g., 246 nm). The aluminum composition of the first light absorbing layer 123a may be in the range of 20% to 50%, and the thickness of the first light absorbing layer 123 may be in the range of 1 nm to 10 nm. For example, the first light absorbing layer 123a may be made of AlGaN, but is not limited thereto.

[0369] The aluminum composition of the second light absorbing layer 123b may be higher than that of the first conductive semiconductor layer 124. The second light absorbing layer 123b may enhance the crystallinity of the first conductive semiconductor layer 124 grown on the light absorbing layer 123 by increasing the aluminum composition reduced by the first light absorbing layer 123a.

[0370] For example, the aluminum composition of the second light absorbing layer 123b may be in the range of 60% to 100%, and the thickness of the second light absorbing layer 123b may be in the range of 0.1 nm to 2.0 nm. The second light absorbing layer 123b may be made of AlGaN or AlN.

[0371] In order to absorb laser light with a wavelength of 246 nm, the first light absorbing layer 123a may be thicker than the second light absorbing layer 123b. The thickness of the first light absorbing layer 123a may be in the range of 1 nm to 10 nm, and the thickness of the second light absorbing layer 123b may be in the range of 0.5 nm to 2.0 nm.

[0372] The thickness ratio of the first light absorbing layer 123a to the second light absorbing layer 123b may be in the range of 2:1 to 6:1. When the thickness ratio is less than 2:1, the first light absorbing layer 123a is too thin, making it difficult to fully absorb laser light. When the thickness ratio is greater than 6:1, the second light absorbing layer 123b is too thin, so that the total aluminum content of the light absorbing layer may be reduced.

[0373] The total thickness of the light absorbing layer 123 may be greater than 100 nm and less than 400 nm. When the thickness is less than about 100 nm, the first light absorbing layer 123a is too thin, making it difficult to fully absorb the 246 nm laser. When the thickness is greater than about 400 nm, the total aluminum content is reduced, and thus the crystallinity may be deteriorated.

[0374] According to the embodiment, the crystallinity can be enhanced by forming the light absorbing layer 123 having a super lattice structure. Due to this structure, the light absorbing layer 123 can be used as a buffer layer for alleviating the lattice mismatch between the growth substrate 121 and the light emitting structure 120.

[0375] See also Fig.31 , the step of removing the growth substrate 121 may include separating the growth substrate 121 by emitting laser L1 from the side where the growth substrate 121 is located. The laser L1 may have a wavelength that can be absorbed by the first light absorption layer 123a. For example, the laser may be a KrF laser with a wavelength of 248nm.

[0376] The energy band gap of the growth substrate 121 and the second light absorbing layer 123b is too high to absorb the laser light L1. However, the first light absorbing layer 123a containing a relatively low aluminum content can be decomposed by absorbing the laser light L1. Therefore, the first light absorbing layer 123a can be separated together with the growth substrate 121.

[0377] Subsequently, the remaining light absorbing layer 123 - 2 on the first conductive semiconductor layer 124 may be removed through a marking process.

[0378] See also Fig.32 , after the second conductive layer 150 is formed over the second conductive semiconductor layer 127, a plurality of grooves 128 may be formed to upwardly pass through a portion of the first conductive semiconductor layer 124 of the light emitting structure 120. Subsequently, an insulating layer 130 may be formed on one side of the groove 128 and over the second conductive semiconductor layer 127. Subsequently, a first electrode 142 may be formed on the first conductive semiconductor layer 124b exposed by the groove 128.

[0379] See also Fig.33 , the first conductive layer 165 may be formed under the insulating layer 130. The first conductive layer 165 may be electrically insulated from the second conductive layer 150 by the insulating layer 130.

[0380] Subsequently, a conductive substrate 170 may be formed under the first conductive layer 165 , and a second electrode pad 166 may be formed on the second conductive layer 150 exposed by the mesa etching process.

[0381] Semiconductor devices can be applied to various light source devices. For example, conceptually, light source devices can include disinfection devices, curing devices, lighting devices, display devices, and car lights. That is, semiconductor devices can be applied to various electronic devices that provide light by being set in their housings.

[0382] The disinfection device can disinfect a desired area by setting the semiconductor device according to the embodiment. The disinfection device can be applied to household appliances such as water purifiers, air conditioners, and refrigerators, but is not limited thereto. That is, the disinfection device can be applied to various products that need to be disinfected (e.g., medical equipment).

[0383] For example, by providing a disinfection device according to an embodiment, a water purifier can disinfect circulating water. The disinfection device can be provided at a nozzle or a discharge port that circulates water and is configured to emit ultraviolet light. In this case, the disinfection device can include a waterproof structure.

[0384] By setting the semiconductor device according to the embodiment, the curing device can cure various liquids. Conceptually, the liquid can include various materials that cure when emitting ultraviolet light. For example, the curing device can cure various types of resins. Alternatively, the curing device can also be used to cure beauty products, such as nail products.

[0385] The lighting device may include a light source module including a substrate and a semiconductor device according to an embodiment. The lighting device may further include: 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 provided by an external source and provide the electrical signal to the light source module. Moreover, the lighting device may include a lamp, a headlight, or a streetlight.

[0386] 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.

[0387] The reflective plate may be disposed on the bottom cover, and the light emitting module may emit light. The light guide plate may be disposed in front of the reflective plate to guide the light emitted by the light emitting module forward. The optical sheet may include a prism sheet, etc., and may be disposed in front of the light guide plate. The display panel may be disposed in front of the optical sheet. The image signal output circuit may provide an image signal to the display panel. The color filter may be disposed in front of the display panel.

[0388] 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.

[0389] The semiconductor device may be a laser diode instead of the above-mentioned light emitting diode.

[0390] Like 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 utilize an electroluminescence phenomenon in which light is emitted when current flows after a p-type first conductive semiconductor and an n-type second conductive semiconductor are bonded to each other, but there are differences in the direction and phase of the emitted light. That is, the laser diode utilizes stimulated emission and constructive interference so that light having a single specific wavelength can be emitted in the same direction with the same phase. Due to these characteristics, the laser diode may be used in optical communication equipment, medical equipment, semiconductor processing equipment, and the like.

[0391] The light receiving device may include, for example, a light detector, which is a transducer configured to detect light and convert the intensity of the light into an electrical signal. The light detector may include a photocell (silicon or selenium), a light output element (cadmium sulfide or cadmium selenide), a photodiode (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 or filled with gas), an infrared (IR) detector, etc., but the present invention is not limited thereto.

[0392] Generally, semiconductor devices such as photodetectors can be manufactured using direct bandgap semiconductors with high photoelectric conversion efficiency. Alternatively, the photodetector can have a variety of structures. As the most common structure, the photodetector can include a pin-type photodetector using a pn junction, a Schottky photodetector using a Schottky junction, and a metal-semiconductor-metal (MSM) photodetector, etc.

[0393] Like a light emitting device, a photodiode may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer having the above structure, and may be formed as a pn junction or a pin structure. The photodiode operates when a reverse bias or zero bias is applied. When light is incident on the photodiode, electrons and holes are generated, causing current to flow. In this case, the amplitude of the current may be approximately proportional to the intensity of the light incident on the photodiode.

[0394] As a photodiode, a photovoltaic cell or a solar cell can convert light into electric current. Similar to a light emitting device, a solar cell can include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer having the above structure.

[0395] In addition, 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, etc.

[0396] In addition, the above-mentioned semiconductor devices are not necessarily implemented only with semiconductors. Depending on the specific situation, the semiconductor device may also include a metal material. For example, semiconductor devices such as light receiving devices 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.

[0397] Although the present invention has been described with reference to exemplary embodiments, these embodiments are only examples and do not limit the present invention. It should be understood by those skilled in the art that various modifications and applications can be made without departing from the essential characteristics of the embodiments. For example, the elements described in detail in the above embodiments can be modified and implemented. In addition, the differences related to these modifications and applications should be understood to be included in the scope of the present invention defined by the appended claims.

Claims

1. A semiconductor device, comprising: A light emitting structure, the light emitting structure comprising a first semiconductor layer, a second semiconductor layer, an electron blocking layer and an active layer, the active layer being arranged between the first semiconductor layer and the second semiconductor layer, and the electron blocking layer being arranged between the active layer and the second semiconductor layer; Wherein, the active layer includes a barrier layer and a well layer; The light emitting structure further includes a first intermediate layer, which is disposed between the electron blocking layer and the first well layer of the active layer, and the first well layer is the well layer closest to the electron blocking layer among the well layers. The first intermediate layer includes a first part and a second part, the aluminum content of the first part is lower than the aluminum content of the electron blocking layer, and the aluminum content of the second part is higher than the aluminum content of the electron blocking layer. wherein the barrier layer and the well layer comprise AlGaN, When the primary ions bombard the light emitting structure and sputter secondary ions containing aluminum from the first semiconductor layer, the active layer, the electron blocking layer, the first intermediate layer, and the second semiconductor layer, secondary ions containing aluminum of corresponding intensity are generated along the thickness direction of the first semiconductor layer, the active layer, the electron blocking layer, the first intermediate layer, and the second semiconductor layer; The secondary ion strength of aluminum is: a first intensity position, which exhibits a maximum intensity in the first intermediate layer and has an intensity of a first intensity; a third intensity position, which exhibits a minimum intensity in the entire region of the light emitting structure, and whose intensity is a third intensity; a fourth intensity position showing a minimum intensity in the first semiconductor layer, whose intensity is a fourth intensity; a second intensity position, located at a position separated from the first intensity and being a position of maximum peak intensity in a region between the first intensity and the fourth intensity, and having an intensity of a second intensity; The first intensity position is separated from the third intensity position in a first direction, and the second intensity position is separated from the first intensity position in the first direction, and the first direction is a thickness direction of the light emitting structure and is a direction from the second semiconductor layer to the first semiconductor layer; wherein the second semiconductor layer includes a second region, and the second region includes a secondary ion intensity between the first intensity and the third intensity; Wherein, the light emitting structure further includes a third region, and the third region includes a secondary ion intensity between the first intensity and the second intensity; and the active layer is arranged in the third region.

2. The semiconductor device according to claim 1, wherein The first portion has an aluminum content of 50% to 70%, and / or the second portion has an aluminum content of 80% to 100%.

3. The semiconductor device according to claim 1, wherein The second portion includes an undoped portion.

4. The semiconductor device according to claim 1, wherein: The thickness of the first intermediate layer is 2 nm to 10 nm.

5. The semiconductor device according to claim 1, wherein The thickness of the first portion is 1 nm to 8 nm.

6. The semiconductor device according to claim 1, wherein The second portion has a thickness of 0.1 nm to 4 nm.

7. The semiconductor device according to claim 1, wherein A thickness ratio of the first portion to the second portion is 10:1 to 1:

1.

8. The semiconductor device according to claim 1, wherein The light emitting structure further includes a second intermediate layer disposed between the electron blocking layer and the first intermediate layer, wherein an aluminum content of the second intermediate layer is lower than an aluminum content of the electron blocking layer.

9. The semiconductor device according to claim 8, wherein: The aluminum content of the second intermediate layer is in the range of 50% to 80%.

10. The semiconductor device according to claim 8, wherein The second intermediate layer includes a third portion not containing a P-type dopant and a fourth portion containing a P-type dopant.

11. The semiconductor device according to claim 10, wherein: The thickness of the third portion is 4 nm to 19 nm, and / or the thickness of the fourth portion is 1 nm to 6 nm.

12. The semiconductor device according to claim 1, wherein The second semiconductor layer includes a semiconductor layer whose aluminum composition gradually decreases with a slope as it moves away from the active layer.

13. The semiconductor device according to claim 1, wherein The first semiconductor layer includes a first conductive semiconductor layer first sublayer, a first conductive semiconductor layer second sublayer, and a first conductive semiconductor layer third sublayer, wherein the first conductive semiconductor layer second sublayer is arranged between the first conductive semiconductor layer first sublayer and the first conductive semiconductor layer third sublayer, and the first conductive semiconductor layer first sublayer, the first conductive semiconductor layer second sublayer, and the first conductive semiconductor layer third sublayer all contain aluminum.

14. The semiconductor device according to claim 1 or 13, wherein: The first semiconductor layer includes a second strength portion located at the second strength position, the strength of the second strength portion is the second strength, and the thickness of the second strength portion is less than the sum of the thicknesses of a pair of well layers and a barrier layer in the active layer.

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