Semiconductor device and semiconductor device package including the same

Abstract

A semiconductor device and a semiconductor device package including the same are disclosed. The semiconductor device includes a light emitting structure including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer disposed 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 ranging from 1:1.25 to 1:100, the second shortest distance W2 being a distance from a first surface to a second point, the first shortest distance W1 being a distance from the first surface to a first point; the first surface is a surface of the second semiconductor layer facing away from the active layer; the first point is a point at which an aluminum composition of the second conductive semiconductor layer is identical to an aluminum composition of a well layer of the active layer closest to the second conductive semiconductor layer; and the second point is a point at which the second conductive semiconductor layer has a dopant composition identical to the aluminum composition.

Description

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

[0002] Cross Reference to Related Applications

[0003] This application claims priority to Korean Patent Application No. 10-2016-0118243 filed on September 13, 2016, Korean Patent Application No. 10-2016-0140466 filed on October 26, 2016, and Korean Patent Application No. 10-2017-0115836 filed on September 11, 2017, in the Republic of Korea, the contents of which are all hereby incorporated by reference. TECHNICAL FIELD

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

[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, etc.

[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 implement various colors of light such as red, green, blue, and ultraviolet light, and also can implement efficient white light by using a phosphor material or combining colors. These light emitting devices also have advantages of low power consumption, semi-permanent life, fast response speed, safety, and environmental friendliness, etc. compared to conventional light sources such as fluorescent lamps, incandescent lamps, etc.

[0007] In addition, when light receiving devices such as optical detectors or solar cells are manufactured using III-V or II-VI compound semiconductors, due to the development of device materials, photocurrent can be generated due to light absorption in various wavelength ranges. Thus, light in various wavelength ranges from gamma rays to radio wavelength ranges can be used. In addition, the light receiving devices have advantages of fast response time, safety, environmental friendliness, and ease of adjusting device materials, and can be easily used for power control, microwave circuits, or communication modules.

[0008] Accordingly, semiconductor devices have been widely used for transmission modules of optical communication apparatuses; light emitting diode backlights to replace cold cathode fluorescent lamps (CCFLs) for forming backlights of liquid crystal display (LCD) devices; white light emitting diode lamps to replace fluorescent lamps or incandescent lamps; vehicle headlamps; traffic signal lamps; and sensors for detecting gases or fires. In addition, semiconductor devices can also be widely used for high frequency application circuits, other power control devices, and even communication modules.

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

[0010] Recently, research on ultraviolet light emitting devices has been actively conducted, but it is difficult to implement ultraviolet light emitting devices vertically, and crystallinity is also reduced in a substrate separation process. SUMMARY

[0011] TECHNICAL PROBLEM

[0012] Embodiments provide a vertical ultraviolet light emitting device.

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

[0014] The problems to be solved by embodiments are not limited to the above, 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 application includes a light emitting structure including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer 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 can include a first surface on which the second electrode is disposed. A ratio (W2:W1) of a second shortest distance W2 from the first surface to a second point to a first shortest distance W1 from the first surface to a first point can be 1:1.25 to 1:100. The first point can be a point at which an aluminum composition of the second conductive semiconductor layer is the same as an aluminum composition of a well layer closest to the active layer of the second conductive semiconductor layer. The second point can 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 embodiments, a vertical ultraviolet light emitting device can be manufactured.

[0019] The light output power can also be enhanced.

[0020] The various advantageous effects and objects of the present application are not limited to the above description and can be easily understood by those skilled in the art from the detailed description of the embodiments of the present application. BRIEF DESCRIPTION OF DRAWINGS

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

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

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

[0024] Figure 4 is a partial enlarged view of Figure 3 ;

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

[0026] Figure 6 is a partial enlarged view of Figure 5 ;

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

[0028] Figure 8 is a partial enlarged view of Figure 7 ;

[0029] Figure 9 is a conceptual view of a semiconductor device according to an embodiment of the present application;

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

[0031] Figure 11a and Figure 11b show SIMS data of a semiconductor structure according to an embodiment of the present application;

[0032] Figure 11c and Figure 11d show SIMS data of a semiconductor structure according to another embodiment of the present application;

[0033] Figure 12 is a graph showing aluminum ion intensity of Figures 11a to 11d ;

[0034] Figure 13a is a graph showing SIMS data of a part (a) in Figure 12

[0035] Figure 13b is a graph showing SIMS data of a part (b) in Figure 12

[0036] Figure 11a is a conceptual view of a second conductive semiconductor layer according to an embodiment of the present application;

[0037] Figure 11a to 11d shows AFM data obtained by measuring a surface of a second conductive semiconductor layer according to an embodiment of the present application;

[0038] Figures 11a to 11d shows AFM data obtained by measuring a surface of a GaN thin film;

[0039] Figure 11a shows AFM data obtained by measuring a surface of a high-speed grown second conductive semiconductor layer;

[0040] Figures 11b to 11d is a conceptual view of a semiconductor device according to an embodiment of the present application;

[0041] Figure 11a and Figure 12 is a graph showing a configuration in which light output power is enhanced as the number of grooves varies;

[0042] Figure 13a is a close-up view of A part of Figure 12

[0043] Figure 13b is a conceptual view of a semiconductor device according to another embodiment of the present application;

[0044] Figure 12 is a plan view of Figure 11a

[0045] Figure 12 is a conceptual view of a semiconductor device package according to an embodiment of the present application;

[0046] Figure 11b is a plan view of a semiconductor device package according to an embodiment of the present application;

[0047] Figure 12 is a modification of Figure 11c

[0048] Figure 12 is a sectional view of a semiconductor device package according to another embodiment of the present application; ​​​​​

[0049] Figure 11d is a conceptual view of a light emitting structure according to an embodiment of the present application;

[0050] Figure 12 is a graph showing an aluminum composition of a light emitting structure according to an embodiment of the present application;

[0051] Figure 12 is a graph showing an aluminum composition of a light emitting structure according to another embodiment of the present application;

[0052] Figure 12 is a graph obtained by measuring a light efficiency of a semiconductor device including a conventional light emitting structure;

[0053] Figure 12 is a graph obtained by measuring a light efficiency of a light emitting structure according to another embodiment of the present application;

[0054] Figure 12 is a graph showing an aluminum composition of a light emitting structure according to still another embodiment of the present application;

[0055] Figure 13a is a conceptual view of a light emitting structure grown on a substrate;

[0056] Figure 12 is a graph showing a process of separating a substrate;

[0057] Figure 13a is a graph showing a process of etching a light emitting structure; and

[0058] Figure 13b is a graph showing a fabricated semiconductor device. DETAILED DESCRIPTION

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

[0060] The details described in the specific embodiments can be understood as being described in relation to other embodiments, even if there is no such description in other embodiments, unless otherwise stated or there is a contradiction.

[0061] For example, when a feature of element A is described in one specific embodiment and a feature of element B is described in another embodiment, an embodiment in which element A and element B are combined with each other should be understood to fall within the scope of the present application, even if it is not explicitly stated, unless otherwise stated or there is a contradiction.

[0062] In describing embodiments, if a component (for example, a layer, film, region, or substrate) is referred to as being "on" another component, it can be directly on the other component or one or more other components can be intervening. Also, the phrase "on" as used herein can mean over, above, below, under, or in other directions in relation to a component.

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

[0064] The light emitting structure according to embodiments of the present application 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 the near ultraviolet wavelength light (UV-A) can be 320 nm to 420 nm, the wavelength of the far ultraviolet wavelength light (UV-B) can be 280 nm to 320 nm, and the wavelength of the deep ultraviolet wavelength light (UV-C) can be 100 nm to 280 nm.

[0066] Figure 14a is a conceptual view of a light emitting structure according to embodiments of the present application; Figure 14b is a graph showing an aluminum composition of a semiconductor structure according to embodiments of the present application.

[0067] Referring to Figure 14c The semiconductor device according to embodiments includes a light emitting structure including a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, and an active layer 126 disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127.

[0068] 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 made of one material selected from a plurality of semiconductor materials of the empirical formula In x1 Al y1 Ga 1-x1-y1 N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1). Also, 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.

[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. The active layer 126 can be converted to a low energy level due to the recombination between the electrons and the holes, and light having an ultraviolet wavelength is generated.

[0070] The active layer 126 can 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 can be formed on the active layer 126, and can be made of a Group III-V or Group II-VI compound semiconductor. Also, the second conductive semiconductor layer 127 can be doped with a second dopant. The second conductive semiconductor layer 127 can be made of a semiconductor material having an empirical formula of In x5 Al y2 Ga 1-x5-y2 N (0≤x5≤1, 0≤y2≤1, and 0≤x5+y2≤1) or one selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant, such as Mg, Zn, Ca, Sr, and Ba, the second conductive semiconductor layer 127 doped with the second dopant can be a p-type semiconductor layer.

[0072] The second conductive semiconductor layer 127 can include a 2-1 (second-primary) 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. An aluminum composition of the 2-1 conductive semiconductor layer 127a can be lower than an aluminum composition of the 2-2 conductive semiconductor layer 127b.

[0073] The electron blocking layer 129 can be disposed between the active layer 126 and the second conductive semiconductor layer 127. The electron blocking layer 129 can block the flow of electrons provided by the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127, thereby increasing the likelihood of recombination of electrons and holes in the active layer 126. The energy band gap of the electron blocking layer 129 can 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 can be made of a semiconductor material having an empirical formula of In x1 Al y1 Ga 1-x1-y1The first layer 129b having a high aluminum content and the second layer 129a having a low aluminum content can be alternately arranged in the electron blocking layer 129.

[0075] Referring to Figure 14d 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 can all include aluminum. Thus, 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 can all be made of AlGaN. However, the present application is not limited thereto.

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

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

[0078] The thickness of the 1-1 portion 129-1 can 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, it can not be possible to effectively block the movement of electrons. When the thickness of the 1-1 portion 129-1 is greater than 4 nm, it can be possible to degrade the efficiency of hole injection into the active layer 126.

[0079] The 1-2 portion 129-2 can include an undoped portion. The 1-2 portion 129-2 can function to prevent the diffusion of a dopant from the second conductive semiconductor layer 127 to the active layer 126.

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

[0081] The aluminum composition of the 2-2 conductive semiconductor layer 127b can be higher than that of the well layer 126a. To generate ultraviolet light, the well layer 126a can have an aluminum composition of approximately 30% to approximately 70%. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is lower than that 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, the present application is not limited thereto in order to prevent the crystallinity of the light emitting structure from deteriorating. For example, in some portions, the aluminum composition of the 2-2 conductive semiconductor layer 127b can be lower than that of the well layer 126a.

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

[0083] The aluminum composition of the 2-1 conductive semiconductor layer 127a can 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 be in sufficient ohmic contact with the p-type ohmic electrode because the resistance between the 2-1 conductive semiconductor layer 127a and the p-type ohmic electrode increases, and thus it is possible to reduce the current injection efficiency.

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

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

[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 can not be provided in some portions, and there can 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 light absorbed is so great that it is possible for the light output power efficiency to decrease.

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

[0088] As the 2-2 conductive semiconductor layer 127b is farther away from the active layer 126, the aluminum component of the 2-2 conductive semiconductor layer 127b can decrease. In addition, as the 2-1 conductive semiconductor layer 127a is farther away from the active layer 126, the aluminum component of the 2-1 conductive semiconductor layer 127a can decrease.

[0089] In this case, the degree to which the aluminum component of the 2-1 conductive semiconductor layer 127a decreases can be greater than the degree to which the aluminum component of the 2-2 conductive semiconductor layer 127b decreases. That is, the change in the aluminum component of the 2-1 conductive semiconductor layer 127a in the thickness direction can be greater than the change in the aluminum component of the 2-2 conductive semiconductor layer 127b in the thickness direction.

[0090] The thickness of the 2-2 conductive semiconductor layer 127b is greater than the thickness of the 2-1 conductive semiconductor layer 127a and the aluminum component contained therein is higher than the aluminum component of the well layer 126a. Therefore, the aluminum component of the 2-2 conductive semiconductor layer 127b can decrease relatively slowly.

[0091] However, the thickness of the 2-1 conductive semiconductor layer 127a is small, and the change in the aluminum component is large. Therefore, the degree to which the aluminum component of the 2-1 conductive semiconductor layer 127a decreases is relatively large.

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

[0093] Figure 14a is a secondary ion mass spectroscopy (SIMS) graph of the light emitting structure according to the first embodiment of the present application, Figure 14b is Figure 14b is a partial enlarged view of

[0094] Referring to Figure 14c and Figure 14d , the aluminum composition and the p-type impurity (Mg) composition of the light emitting structure can change as the thickness thereof decreases. The aluminum composition of the second conductive semiconductor layer 127 can decrease, and the p-type impurity (Mg) composition of the second conductive semiconductor layer 127 can increase toward the surface thereof.

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

[0096] When the ratio (W2:W1) of the second shortest distance W2 to the first shortest distance W1 is less than 1:1.25, the first shortest distance W1 and the second shortest distance W2 are very 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 can decrease or the stress applied to the substrate can increase, 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 by a spectrum measured by SIMS. The range of the first point P11 can be defined as a portion of the second conductive semiconductor layer having the same aluminum composition as the well layer of the active layer.

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

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

[0100] The unit of the value of the dopant of the second conductive semiconductor layer during the measurement can vary depending on the circumstances. However, the boundary region between the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b can be included in a range of a point at which a region including a turning point of the aluminum component of the second conductive semiconductor layer intersects the spectrum of the dopant of the second conductive semiconductor layer. Thus, the boundary region between the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b can be measured and its range can be defined.

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

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

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

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

[0105] Figure 14d is a SIMS graph of a light emitting structure according to a second embodiment of the present application, Figure 15 is Figure 16a is a partial enlarged view of Figure 16b is a SIMS graph of a light emitting structure according to a third embodiment of the present application, Figure 17 isFigure 15 a close-up view of a portion of

[0106] Referring to Figure 15 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. See, for example, Figure 16a It can be seen that the first point P13 and the second point P23 are close to each other.

[0107] Further, it can be seen that the ratio (H1:H2) of the first difference H1 to the second difference H2 can be 1:1.2 to 1:10, the first difference H1 being 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 being 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 can be adjusted to 1% to 10%.

[0109] Figure 16a is a conceptual view of a semiconductor structure according to an embodiment of the present application, Figure 16b is a graph showing the aluminum composition of a semiconductor structure according to an embodiment of the present application.

[0110] Referring to Figure 17 and 10 A semiconductor device according to an embodiment includes a semiconductor structure 120 including a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, and an active layer 126 disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127.

[0111] The semiconductor structure 120 according to an embodiment of the present application 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 the near ultraviolet wavelength light (UV-A) can be 320 nm to 420 nm, the wavelength of the far ultraviolet wavelength light (UV-B) can be 280 nm to 320 nm, and the wavelength of the deep ultraviolet wavelength light (UV-C) can be 100 nm to 280 nm.

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

[0114] Also, in describing embodiments, a composition can be understood in terms of a difference in percentage (and / or in percentage points) of the composition of each semiconductor layer. For example, when a first semiconductor layer has an aluminum composition of 30% and a second conductive semiconductor layer has an aluminum composition of 60%, the aluminum composition of the second conductive semiconductor layer can be expressed as being 30% higher than the aluminum composition of the first semiconductor layer.

[0115] The first conductive semiconductor layer 124 can be made of a Group III-V or Group II-VI compound semiconductor and can be doped with a first dopant. The first conductive semiconductor layer 124 can be made of one of a plurality of semiconductor materials of the empirical formula In x1 Al y1 Ga 1-x1-y1 N (0≤x1≤1, 0≤y1≤1, and 0≤x1+y1≤1). Also, 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 application 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 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 composition of 50% to 80%. When the aluminum composition of the 1-1 conductive semiconductor layer 124a is greater than 50%, light extraction efficiency can be improved by reducing the absorption rate of ultraviolet-C (UV-C) wavelength light emitted from the active layer 126. When the aluminum composition of the 1-1 conductive semiconductor layer 124a is less than 80%, current injection characteristics of the active layer 126 and current diffusion characteristics of the 1-1 conductive semiconductor layer 124a can be ensured.

[0118] The 1-2 conductive semiconductor layer 124c can 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 can 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 124c can 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 can be improved by reducing the absorption rate 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%, the current injection characteristics of the active layer 126 and the current diffusion characteristics of the 1-2 conductive semiconductor layer 124c can 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 the aluminum composition of the well layer 126a. Accordingly, when the active layer 126 emits ultraviolet wavelength light, the absorption rate of the ultraviolet wavelength light in the semiconductor structure 120 can be reduced.

[0122] Further, when the aluminum composition of the 1-2 conductive semiconductor layer 124c is higher than the aluminum composition 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. Accordingly, the light extraction efficiency of the semiconductor structure 120 can be improved.

[0123] The 1-2 conductive semiconductor layer 124c can be thinner than the 1-1 conductive semiconductor layer 124a. The thickness of the 1-1 conductive semiconductor layer 124a can 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 disposed after sufficiently securing the thickness of the 1-1 conductive semiconductor layer 124a having a high aluminum composition. Accordingly, the overall crystallinity of the semiconductor structure 120 can be improved.

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

[0125] Also, when the intermediate layer 124b is in contact with the first electrode, the aluminum component of the intermediate layer 124b can be lower than the aluminum component of the 1-1 conductive semiconductor layer 124a and the aluminum component of the 1-2 semiconductor layer 124c to reduce the resistance between the intermediate layer 124b and the first electrode, thus ensuring the current injection efficiency.

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

[0127] When the wavelength of the LLO laser is 200 nm to 300 nm, the intermediate layer 124b can have an aluminum component 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 component of the intermediate layer 124b can be increased to correspond to the wavelength of the LLO laser. For example, the aluminum component of the intermediate layer 124b can 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 can not be able to absorb the light emitted from the active layer 126. Thus, the light extraction efficiency can be improved. According to an embodiment of the present application, the wavelength of the LLO laser can be less than the wavelength of the light emitted from the well layer 126a. Thus, the intermediate layer 124b can have a suitable aluminum component to make the intermediate layer 124b absorb the LLO laser but not absorb the light emitted from the well layer 126a.

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

[0131] The active layer 126 can be disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127. The active layer 126 can include a plurality of well layers 126a and a plurality of barrier layers 126b. The well layer 126a is a layer in which a first carrier (electron or hole) injected through the first conductive semiconductor layer 124 is combined with a second carrier (hole or electron) injected through the second conductive semiconductor layer 127. When the first carrier (or the second carrier) in the conduction band and the second carrier (or the first carrier) 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 (energy band gap) between the conduction band and the valence band of the well layer 126a can be generated.

[0132] The active layer 126 can 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 can include a plurality of well layers 126a and a plurality of barrier layers 126b. Each of the well layers 126a and the barrier layers 126b can have a chemical formula of Inx x2 Al y2 Ga 1-x2-y2 N (0≤x2≤1, 0<y2≤1, and 0≤x2+y2≤1). The aluminum component contained in the well layer 126a can be different according to the emission wavelength.

[0134] The second conductive semiconductor layer 127 can be formed on the active layer 126 and can be made of a III-V or II-VI compound semiconductor. Also, the second conductive semiconductor layer 127 can be doped with a second dopant.

[0135] The second conductive semiconductor layer 127 can be made of a semiconductor material having a chemical 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 can be a p-type semiconductor layer. However, the present application is not limited thereto, and the second conductive semiconductor layer 124 can be an n-type semiconductor layer.

[0137] The second conductive semiconductor layer 127 can 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 component of the 2-1 conductive semiconductor layer 127a can be lower than the aluminum components of the 2-2 conductive semiconductor layer 127b and the 2-3 conductive semiconductor layer 127c.

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

[0139] The barrier layer 129 can be made of a material selected from a plurality of semiconductor materials of the empirical formula In x1 Al y1 Ga 1-x1-y1 N (0≤x1≤1, 0

[0140] According to an embodiment, the first conductive semiconductor layer 124, the active layer 126, the second conductive semiconductor layer 127, and the barrier layer 129 can all include aluminum. Thus, the first conductive semiconductor layer 124, the active layer 126, the second conductive semiconductor layer 127, and the barrier layer 129 can contain the composition AlGaN, InAlGaN, or AlN.

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

[0142] The barrier layer 129 can include a 1-1 portion 129a and a 1-2 portion 129c.

[0143] The aluminum composition contained in the 1-1 portion 129a can increase from the first conductive semiconductor layer 124 toward the second conductive semiconductor layer 127.

[0144] The aluminum composition of the 1-1 portion 129a can be 80% to 100%. Thus, the 1-1 portion 129a of the barrier layer 129 can be a portion containing the highest aluminum composition in the semiconductor structure 120.

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

[0146] The thickness of the 1-1 portion 129a can be about 0.1 nm to about 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 can form a thickness of 0.1 nm or more. Also, in order to secure the injection efficiency of the second carriers injected from the second conductive semiconductor layer 127 to the active layer 126, the 1-1 portion 129a can form a thickness of 4 nm or less.

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

[0148] The 1-3 portion 129b disposed between the 1-1 portion 129a and the 1-2 portion 129c can include an undoped portion not containing a dopant. Accordingly, the 1-3 portion 129b can be used to prevent diffusion of the second dopant from the second conductive semiconductor layer 127 to the active layer 126.

[0149] The second conductive semiconductor layer 127 can 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 can be greater than 10 nm and less than 50 nm. For example, the thickness of the 2-2 conductive semiconductor layer 127b can be equal to 25 nm. When the thickness of the 2-2 conductive semiconductor layer 127b is greater than or equal to 10 nm, a current spreading characteristic of the 2-2 conductive semiconductor layer 127b can be secured. Further, when the thickness is less than or equal to 50 nm, an injection efficiency of injecting a second carrier into the active layer 126 can be secured and an absorption rate of light emitted from the active layer 126 in the 2-2 conductive semiconductor layer 127b can be reduced.

[0151] An aluminum component contained in the 2-2 conductive semiconductor layer 127b can be higher than an aluminum component contained in the well layer 126a. In order to generate ultraviolet light, the aluminum component of the well layer 126a can be approximately 30% to approximately 70%. Accordingly, the aluminum component of the 2-2 conductive semiconductor layer 127b can be in a range of 40% to 80%.

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

[0153] The aluminum component of the 2-1 conductive semiconductor layer 127a can be lower than the aluminum component of the well layer 126a. When the aluminum component of the 2-1 conductive semiconductor layer 127a is higher than the aluminum component of the well layer 126a, the 2-1 conductive semiconductor layer 127a and the second electrode cannot be sufficiently ohmic-contacted due to an increase in resistance therebetween, and a current injection efficiency can also be reduced.

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

[0155] The thickness of the 1-1 conductive semiconductor layer 127a can be 1 nm to 30 nm. Thus, because the 2-1 conductive semiconductor layer 127a is capable of absorbing ultraviolet light, it can be more 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 1 nm, the resistance of the 2-1 conductive semiconductor layer 127a can be reduced, thereby improving the electrical characteristics of the semiconductor device. Further, when the thickness is less than or equal to 30 nm, 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 can 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 can 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, thereby the current injection efficiency can be improved. Further, when the thickness ratio is less than 1:20, the thickness of the 2-1 conductive semiconductor layer 127a increases, thereby the deterioration of crystallinity can be slowed down. When the 2-1 conductive semiconductor layer 127a is too thin, the aluminum component needs to rapidly change within the thickness range, thus the crystallinity can be reduced.

[0158] The aluminum component contained in the 2-2 conductive semiconductor layer 127b can decrease as it is farther away from the active layer 126. Further, the aluminum component contained in the 2-1 conductive semiconductor layer 127a can decrease as it is farther away from the active layer 126.

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

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

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

[0162] As a result, the 2-1 conductive semiconductor layer 127a has a relatively small thickness but a relatively large change in aluminum. Therefore, the 2-1 conductive semiconductor layer 127a can have a relatively high degree of reduction in 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 has a higher aluminum component than the aluminum component of the well layer 126a. Thus, the aluminum contained in the 2-2 conductive semiconductor layer 127b can be reduced relatively slowly.

[0164] Since the 2-1 conductive semiconductor layer 127a is relatively thin and the aluminum component has a large change in thickness, the aluminum component can be changed while the 2-1 conductive semiconductor layer 127a is grown relatively slowly.

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

[0166] As described above, the 2-1 conductive semiconductor layer 127a can have a thickness of 1 nm to 10 nm, the 2-2 conductive semiconductor layer 127b can have a thickness of 10 nm to 50 nm, and the 2-3 conductive semiconductor layer 127c can have a thickness of 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 can 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 can secure the 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 can secure the optical characteristics (e.g., optical output power) of the semiconductor device. However, the present application 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 can 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 the embodiment of the present application can have a first point P1 at which the aluminum composition of the semiconductor structure is the highest and a third point P3 at which the aluminum composition of the semiconductor structure is the lowest. Here, the first point P1 can be the 1-1 portion 129a of the barrier layer 129 at which the aluminum composition is the highest, and the third point P3 can be the 2-1 conductive semiconductor layer 127a at which the aluminum composition is the lowest.

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

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

[0171] Therefore, the aluminum composition ratio between the third point P3 and the first point P1 can 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 can 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 can increase, thereby reducing light absorption at the third point P3.

[0172] The 1-1 conductive semiconductor layer 124a can have an aluminum composition of 50% to 80%. The intermediate layer 124b can have an aluminum composition of 30% to 70%. In this case, the aluminum composition of the intermediate layer 124b can be lower than the aluminum composition of the 1-1 conductive semiconductor layer. Therefore, the aluminum composition ratio between the fourth point P4 and the second point P2 can 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 can increase, thereby improving crystallinity. When the aluminum composition ratio is less than or equal to 1:0.9, the aluminum composition of the intermediate layer 124b can increase, thereby reducing absorption of ultraviolet wavelength light.

[0174] Figure 15 and Figure 18 SIMS data of a semiconductor structure according to an embodiment of the present application is shown, Figure 19 and Figure 18 SIMS data of a semiconductor structure according to another embodiment of the present application is shown,Figure 18 is a graph showing Figure 20 aluminum ion intensity of Figure 20 is a graph showing Figure 21 partially enlarged SIMS data of (a), Figure 22 is a graph showing Figure 21 converted into linear scale of (b).

[0175] Referring to Figure 23 , the semiconductor structure can have components of aluminum (Al), gallium (Ga), a first dopant, a second dopant, oxygen (O), and carbon (C) that vary in a direction from the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127. The first dopant can be silicon (Si), and the second dopant can be magnesium (Mg). However, the present application 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 to a target surface and counting the number of secondary ions emitted. In this case, the primary ions can be selected from O2 + , Cs + , Bi + , etc., the acceleration voltage can be adjusted to be in a range of about 20 keV to 30 keV, the emission current can be adjusted to be in a range of about 0.1 pA to 5.0 pA, and the target area can be 20 nm x 20 nm.

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

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

[0180] In addition, SMIS analysis results can be obtained by interpreting spectra of secondary ion intensities or doping concentrations of each material. When secondary ion intensities or doping concentrations are interpreted, the results can include noise produced in a factor of 0.9 to 1.1. Accordingly, the word "identical / equivalent" refers to noise that is proportional to a factor of 0.9 to 1.1 with respect to a specific secondary ion intensity or doping concentration.

[0181] Figure 20 Aluminum and gallium in the SIMS data of are spectral data of secondary ion intensities, and the first dopant, the second dopant, oxygen, and carbon are data obtained by measuring doping concentrations. That is,Figure 21 The SIMS data and the doping concentration data are shown in a single graph.

[0182] Referring to Figure 22 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 can have independent relationships.

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

[0184] The method of measuring 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 (i.e., the Y axis) is shown and converted to a logarithmic scale.

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

[0186] The ion intensity according to the embodiment can increase or decrease depending on the measurement conditions. However, the secondary ion intensity (e.g., aluminum ions) 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. Thus, even if the measurement conditions change, the change in the ion intensity in the thickness direction can be similar.

[0187] The doping concentration of the second dopant can be the highest on the surface and can gradually decrease as it moves away from the surface. The second dopant can exist in all regions of the second conductive semiconductor layer and some regions of the active layer, but is not limited thereto. The second dopant can be disposed only in the second conductive semiconductor layer, but can diffuse upward to the active layer. Thus, the implantation efficiency of implanting the second dopant into the active layer can 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 and second carriers can occur, thereby reducing the reliability and / or light emitting efficiency of the semiconductor device.

[0188] The first dopant can 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 can even be partially distributed in the active layer. Thus, the injection efficiency of the first carriers injected into the active layer can be improved, and the radiation recombination efficiency between the first carriers and the second carriers can also be improved.

[0189] It can be confirmed that Figure 23 It is shown that Figure 24 the same trend.

[0190] Referring to Figure 25 and Figure 24 , the aluminum ion intensity can include aluminum ion intensities of the first point to the sixth point P1, P2, P3, P4, P5, and P6. Figure 1 The (a) portion of Figure 25 shows the aluminum ion intensity of Figure 26 The (b) portion of Figure 27 shows the aluminum ion intensity of Figure 28 The (c) portion of Figure 26 shows the aluminum ion intensity of Figure 25 The (d) portion of Figure 27 shows the aluminum ion intensity of

[0191] Figure 28 The (c) portion of Figure 29 and the (d) portion of Figure 29 show distributions similar to the distribution of the aluminum ion intensity of the (a) portion of Figure 30 except for a concave-convex portion P7 in which the ion intensity is changed between the first point P1 and the third point P3. For example, according to the embodiments of the (c) portion of Figure 31 and the (d) portion of

[0192] The aluminum ion intensity of the first point P1 can be the highest in the semiconductor structure 120. Since the aluminum ion intensity of the first point P1 is the highest, the first carriers and the second carriers can be prevented from being non-radiatively recombined in the second conductive semiconductor layer. Thus, the light output power of the semiconductor device can be improved. The first point P1 can 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 can correspond to a point having the highest aluminum ion intensity among a plurality of points having aluminum ion intensities extending from the first point P1 in the first direction D (i.e., the direction in which the depth increases).

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

[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 first carrier energy injected into the active layer in the first conductive semiconductor layer 124. Accordingly, the light emission efficiency can be improved, thereby improving the light output power characteristics of the semiconductor device.

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

[0197] When the third point P3 is in contact with the second electrode, because the aluminum ion intensity of the third point P3 is the lowest, the resistance between the third point P3 and the second electrode can be low. Accordingly, the injection efficiency of the current injected into the semiconductor structure 120 through the second electrode can be secured.

[0198] The fourth ion intensity of the fourth point P4 can correspond to a point at which the aluminum ion intensity is the 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 can absorb the 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] Also, when the fourth point P4 is in contact with 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 a point at which the aluminum ion intensity is the lowest in the first direction from the second point P2.

[0201] The fifth point P5 can be disposed between the second point P2 and the fourth point P4. The aluminum ion intensity of the fifth point P5 can be between the aluminum ion intensity of the second point P2 and the aluminum ion intensity of the fourth point P4. The fifth point P5 can be a single specific point, or can be formed as a single layer. By uniformly distributing the current injected through the fourth point P4 in the layer including the fifth point P5, it is possible to improve uniformity of the current density per unit area injected into the active layer.

[0202] In addition, a plurality of points (or layers) having the same or similar aluminum ion intensity as the fifth point P5 can be separately provided from the fourth point P4 in the first direction D. That is, there can be a portion in which the ion intensity increases from the fourth point P4 in the first direction. Accordingly, the fourth point P4 can be provided between a plurality of points (or layers) having the same aluminum ion intensity as the fifth point P5. However, the present application is not limited thereto, and the aluminum ion intensity of a region separated from the fifth point P5 in the first direction D and spaced farther apart than the fourth point P4 in the first direction D can be higher than the aluminum ion intensity of the fifth point P5.

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

[0204] A region between the tenth point P10 and the third point P3 can 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 third point P3 electrically connected to the second electrode can have lower conductivity than the fourth point P4 connected to the first electrode. Accordingly, the ion intensity of the third point P3 can be less than the ion intensity of the fourth point P4.

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

[0207] A region S11 located between the third point P3 and the tenth point P10 can have a portion in which the aluminum ion intensity decreases toward the surface S0, and also has a reverse portion P6 in which the aluminum ion intensity does not decrease toward the surface S0. The reverse portion P6 can be a portion in which the aluminum ion intensity increases or remains constant toward the surface S0.

[0208] When the reverse portion P6 is provided 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. Accordingly, the light output power characteristics and electrical characteristics of the semiconductor device can be enhanced.

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

[0210] Therefore, in the process of continuously lowering or raising the temperature, a large amount of aluminum is included immediately 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 formation of the tenth point P10 having the same aluminum ion intensity as the point having the lowest aluminum ion intensity in the active layer, the aluminum composition can be controlled by temperature, and the reverse portion P6 can be arranged to secure the crystallinity of the second conductive semiconductor layer and to secure the current spreading characteristics.

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

[0213] Referring to Figure 32 In a graph of the aluminum ion intensity, the semiconductor structure can include a first portion S1, a second portion S2, and a third portion S3 in the direction in which the depth increases.

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

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

[0216] However, the present application is not limited thereto, and the height of the second point can be the same as the height of the fifth point. In this case, the second portion can 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 can have a plurality of peaks S21 and a plurality of valleys S22. The valleys S22 can be the ion intensity of the well layer, and the peaks S21 can be the ion intensity of the barrier layer.

[0218] The ratio M1 of the ion intensity of the point of the wave trough S22 to the first point P1 can be 1:0.4 to 1:0.6, and the ratio M2 of the ion intensity of the wave trough S22 to the wave peak S21 can be 1:0.5 to 1:0.75.

[0219] When the ratio M1 of the ion intensity of the point of the wave trough S22 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 disposed closer than the active layer, can be secured, and the first carrier can be prevented from being injected into the second conductive semiconductor layer to increase the possibility of radiative recombination in the active layer. Accordingly, the light output power characteristics of the semiconductor device can be improved.

[0220] Further, when the 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 than the active layer, can be secured.

[0221] When the ratio M2 of the ion intensity of the wave trough S22 to the wave peak S21 is greater than or equal to 1:0.5, the barrier layer can effectively prevent the 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] Further, when the ratio M2 is less than or equal to 1:0.75, the crystallinity of the semiconductor structure can be secured, the wavelength change due to strain can be reduced, and / or the possibility of radiative recombination can be increased by reducing the stress generated due to the difference in lattice constant between the well layer and the barrier layer.

[0223] The ratio of the ratio M1 to the ratio M2 can satisfy a range of 1:0.3 to 1:0.8. Accordingly, a portion in which the ratio of the ratio M1 to the ratio M2 satisfies the range of 1:0.3 to 1:0.8 can be a portion in which the active layer is actually disposed.

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

[0225] Also, the distance between the adjacent wave troughs S22 can be less than the distance between the first point P1 and the second point P2. This is because the thicknesses of the well layer and the barrier layer are less than the entire thickness of the active layer 126.

[0226] The first portion S1 can include a surface region S11 whose ion intensity is less than the ion intensity of the fourth point P4. In this case, the ion intensity of the surface region S11 can decrease in a direction opposite to the first direction D.

[0227] According to the 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 PI and the third point P3 can 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 decreases, and thus the aluminum component of the first point PI can be sufficiently reduced. Therefore, the contact resistance with the second electrode can be reduced.

[0228] Further, when the intensity difference ratio D1 : D2 is less than or equal to 1 : 2.5 (e.g., 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 the aluminum component being too low, and thus degradation of the optical properties of the semiconductor can be prevented.

[0229] The ratio (D3 : D4) of the third intensity difference D3 between the seventh point P7 and the first point PI to the fourth intensity difference D4 between the fourth point P4 and the third point P3 can 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 relatively increases, and thus the aluminum component can be sufficiently reduced. Therefore, the contact resistance with the second electrode can be reduced. Further, when the component ratio is less than or equal to 1 : 2, a decrease in crystallinity due to a rapid change in the aluminum component in the thickness range of the 2-1 conductive semiconductor layer 127a can be prevented. Moreover, light emitted from the active layer 126 can be prevented from being absorbed by the 2-1 conductive semiconductor layer 127a due to the aluminum component being too low.

[0231] Generally, 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 of the third point P3 is not measured or significantly decreases. Therefore, the ratio (D1 : D2) of the first intensity difference D1 to the second intensity difference D2 and the ratio (D3 : D4) of the third intensity difference D3 to the fourth intensity difference D4 can deviate from the above-described 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 can 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 increased. 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 alleviated.

[0233] The ion intensity ratio (P3:P1) of the third point P3 to the first point P1 can be in the range of 1:2 to 1:4. When the ion intensity 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 intensity of the third point P3 greatly decreases, and thus the contact resistance with the second electrode can be reduced. In addition, when the ion intensity 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 intensity of the third point P3 can increase. Thus, light can 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 can 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, and thus the first carrier can be effectively prevented 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, and thus the well layer can generate ultraviolet wavelength light.

[0235] The ion intensity ratio of the third point P3 to the fourth point P4 can be in the range of 1:1.1 to 1:2. When the ion intensity ratio of the third point P3 to the fourth point P4 is greater than or equal to 1:1.1, the ion intensity of the fourth point P4 increases, and thus the absorption rate of the ultraviolet wavelength light can be reduced. In addition, when the ion intensity ratio of the third point P3 to the fourth point P4 is less than or equal to 1:2, the ion intensity of the third point is sufficiently secured, and thus the absorption rate of the ultraviolet wavelength light can be reduced.

[0236] The ion intensity ratio of the second point P2 to the first point P1 can 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, and thus the first carrier can be effectively prevented 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 can reach a balance in concentration, and the amount of light emitted by the semiconductor device can be increased.

[0237] The ion intensity ratio of the fourth point P4 to the second point P2 can be in the range of 1:1.2 to 1:2.5. When the ion intensity 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 can be reduced. Also, when the ion intensity ratio of the fourth point P4 to the second point P2 is less than or equal to 1:2.5, the ion intensity of the fourth point P4 increases, and thus the absorption rate of ultraviolet wavelength light can be reduced.

[0238] The ion intensity ratio of the fifth point P5 to the second point P2 can be in the range of 1:1.1 to 1:2.0. According to an embodiment, a semiconductor structure emitting deep ultraviolet light can be made of a GaN-based material including a large amount of aluminum, compared to a semiconductor structure emitting blue light. Accordingly, 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 secured. Also, 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, and thus the crystallinity can be improved.

[0239] The ion intensity ratio of the fourth point P4 to the fifth point P5 can be in the range of 1:1.1 to 1:2.0. When the ion intensity ratio of the fourth point P4 to the fifth point P5 is greater than or equal to 1:1.1, the ion intensity of the fifth point P5 increases, and thus the crystallinity can be improved. Also, when the ion intensity ratio of the fourth point P4 to the fifth point P5 is less than or equal to 1:2.0, the ion intensity of the fourth point P4 increases, and thus the absorption rate of ultraviolet wavelength light can be reduced.

[0240] In Figure 33 and Figure 30 , the aluminum ion intensity is expressed in a logarithmic scale. However, the present application is not limited thereto, and the aluminum ion intensity can be expressed in a linear scale.

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

[0242] For example, the first sub-level of the first order can be 1.0×10 1 , and the second sub-level of the first order can be 2.0×10 1The third sub-level of the first order of magnitude can be 3.0 × 10⁻⁶. 1 The ninth sub-level of the first order of magnitude can be 9.0 × 10⁻⁶. 1 The tenth sub-level of the first order of magnitude can be 1.0 × 10⁻⁶. 2 In other words, the tenth sub-level of the first order of magnitude can be equal to the first sub-level of the second order of magnitude. Figure 31 In the middle, the dashed lines represent every two sub-levels.

[0243] Figure 32 This is a conceptual view of the second conductive semiconductor layer according to an embodiment of the present invention. Figure 33 The AFM data obtained by measuring the surface of the second conductive semiconductor layer according to an embodiment of the present invention is shown. ​ The AMF data obtained by measuring the surface of the GaN thin film are shown. ​ The AFM data obtained by measuring the surface of a rapidly growing second conductive semiconductor layer is shown.

[0244] See ​ 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 in contact with the second electrode. The features of these layers can be described using the above description.

[0245] The surface of the 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 more than about 10 or 20 nm above the average surface height. Each cluster C1 may be formed due to a lattice mismatch between aluminum (Al) and gallium (Ga).

[0246] According to an embodiment, the 2-1 conductive semiconductor layer 127a contains aluminum, and the amount of aluminum varies considerably depending on the 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 as a single layer but as clusters C1 on the surface. Each cluster C1 may contain Al, Ga, N, Mg, etc. However, the present invention is not limited thereto.

[0247] See ​ As can be seen, clusters C1 are formed on the surface of the second conductive semiconductor layer 127 in the shape of relatively bright dots. According to an embodiment, the 2-1 conductive semiconductor layer 127a has an aluminum content of 1% to 10%, and thus the 2-1 conductive semiconductor layer 127a can be formed in the form of clusters C1 to increase the bonding area. Therefore, electrical characteristics can be enhanced.

[0248] on the surface of the second conductive semiconductor layer 127 per average 1 μm 2 One to eight clusters C1 can be observed. Here, the average is an average of a plurality of values measured at about 10 or more different positions. By measuring ​ The result obtained at the position E1 is that 12 clusters C1 are observed per unit area (2 μm x 2 μm). Only clusters C1 protruding more than 25 nm from the surface are measured. By adjusting the contrast of the AFM image, it can be ensured that only clusters C1 protruding more than 25 nm from the surface can be output.

[0249] The density of clusters C1 using a conversion unit based on the measurement result can be 1 x 10 -8 / cm 2 to 8 x 10 -6 / cm 2 When the density of clusters C1 is less than 1 x 10 -8 / cm 2 , the contact area is relatively reduced, and thus the contact resistance with the second electrode can be increased.

[0250] Further, when the density of clusters C1 is greater than 8 x 10 -6 / cm 2 , light emitted from the active layer 126 is absorbed by Ga contained in some clusters, and thus the light output power can be reduced.

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

[0252] Referring to ​ , it can be seen that no cluster is observed from the surface of the GaN thin film. This is because the GaN thin film is formed as a single layer as the density of clusters increases. Thus, it can be seen that when the GaN thin film is formed between the second conductive semiconductor layer and the second electrode, no cluster is formed on the contact surface.

[0253] Referring to ​ , it can be seen that clusters do not grow well when the second conductive semiconductor layer is grown at a high speed. Thus, it can be seen that when the second conductive semiconductor layer is grown at a high speed, although the aluminum composition of the second conductive semiconductor layer is controlled to be in the range of 1% to 10% at its surface, clusters C1 are not formed. For example, ​ is a photograph obtained by measuring the surface after P-AlGaN is grown at a speed of 0.06 nm / s.

[0254] That is, it can be seen that the surface layer should have an aluminum component of 1% to 10% and also have a very low growth rate 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 can 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 can 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 component can be grown by etching Ga at a high temperature at which AlGaN is grown, and thus the ohmic characteristic thereof can be reduced. When the growth rate ratio is greater than 1:0.8, the growth rate of the 2-1 conductive semiconductor layer is very high, and thus the crystallinity can be reduced.

[0256] ​ is a conceptual view of a semiconductor device according to an embodiment of the present application, ​ and ​ is a graph showing a configuration in which light output power is enhanced as the number of grooves varies, ​ is ​ is a magnified view of A portion of

[0257] Referring to ​ , a semiconductor device according to an embodiment can 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 electrically connected with the first conductive semiconductor layer 124, and a second electrode 146 electrically connected with the second conductive semiconductor layer 127.

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

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

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

[0261] Each of the first and second electrodes 142 and 146 can be an ohmic electrode. Each of the first and second electrodes 142 and 146 can be made of at least one of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), 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 is not limited thereto. For example, the first electrode can have a plurality of metal layers (e.g., Cr, Al, and Ni), and the second electrode can be made of ITO.

[0262] Referring to ​ When the GaN-based semiconductor structure 120 emits ultraviolet light, the GaN-based semiconductor structure 120 can include aluminum. As the aluminum composition of the semiconductor structure 120 increases, the current spreading characteristics in the semiconductor structure 120 can decrease. Also, the active layer 126 can have an increased amount of light emitted to the side when the active layer 126 includes aluminum and emits ultraviolet light, as compared to a GaN-based blue light emitting device (TM mode). The TM mode can occur primarily in ultraviolet semiconductor devices.

[0263] An ultraviolet semiconductor device has decreased current spreading characteristics as compared to a blue GaN-based semiconductor device. Therefore, the ultraviolet semiconductor device needs to have a relatively large number of first electrodes 142 disposed therein as compared to the blue GaN-based semiconductor device.

[0264] As the aluminum composition increases, the current spreading characteristics can deteriorate. Referring to ​ , the current spreads only at points adjacent to each first electrode 142, and the current density can decrease rapidly at points away from each first electrode 142. Therefore, the effective light emitting area P2 can be made narrow.

[0265] An area up to a boundary at which 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 area P2. For example, the effective light emitting area P2 can be adjusted depending on the injected current level and the aluminum composition in a range of less than 40 μm from the center of each recess 128.

[0266] The current density of the low current density region P3 can be lower than the current density of the effective light emitting region P2, and thus the light quantity of the low current density region P3 is less than the light quantity of the effective light emitting region P2. Therefore, the light output power can be enhanced by disposing a large number of the 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 superior current spreading characteristic, it is preferable to minimize the area of the recesses 128 and the first electrodes 142. This is because the area of the active layer 126 decreases as the area of the recesses 128 and the first electrodes 142 increases. However, according to the embodiment, since the aluminum composition is high, the current spreading characteristic is relatively low. Therefore, it is preferable to reduce the low current density region P3 by increasing the area and / or the number of the first electrodes 142 although the area of the active layer 126 decreases or to preferably dispose a reflective structure in the low current density region P3.

[0268] Referring to ​ When the number of the recesses 128 is increased to 48, the recesses 128 can be arranged in a zigzag form, instead of being arranged straight in a horizontal or vertical direction. In this case, the area of the low current density region C3 can be reduced, and thus most of the active layer 126 can participate in light emission.

[0269] The ultraviolet light emitting device can have a reduced current spreading 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 the current, a relatively large number of the recesses 128 can be formed compared to the GaN-based semiconductor structure 120, and then the first electrodes 142 can be disposed on the recesses 128.

[0270] Referring to ​ , the first insulating layer 131 can electrically insulate the first electrodes 142 from the active layer 126 and the second conductive semiconductor layer 127. In addition, the first insulating layer 131 can 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 can be used to prevent the side surface of the active layer 126 from being oxidized during the process of the semiconductor device.

[0271] The first insulating layer 131 can be formed of a material selected from SiO2, Si x O y , Si3N4, Si x N y , SiO x N yThe first insulating layer 131 is made of at least one material selected from, but is not limited to, Al2O3, TiO2, and AlN. The first insulating layer 131 can be formed as a single layer or multiple layers. For example, the first insulating layer 131 can be a distributed Bragg reflector (DBR) with a multilayer structure comprising Si oxide or Ti compound. However, the invention is not limited thereto, and the first insulating layer 131 can include various reflective structures.

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

[0273] The diameter W3 of the first electrode 142 can be from 24 μm to 50 μm. When this range is met, it is advantageous in terms of current diffusion, and a large number of first electrodes 142 can 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 can 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 disposed in the region of the first conductive semiconductor layer 124 can be sufficiently ensured, and the current diffusion characteristics are also ensured.

[0274] The diameter W1 of each groove 128 can be from 38 μm to 60 μm. The diameter W1 of each groove 128 can be defined as the maximum area of ​​the groove disposed below the second conductive semiconductor layer 127. The diameter W1 of each groove 128 can also 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 can be ensured in the region where the first electrode 142 is electrically connected to the first conductive semiconductor layer 124 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, the volume of the active layer 126 can be prevented from being reduced to accommodate the first electrode 142, which could potentially degrade the luminous efficiency.

[0276] The slope angle θ5 of each groove 128 can be between 70 and 90 degrees. When this range is met, it is advantageous for forming the first electrode 142 on the top of the groove 128, and a large number of grooves 128 can be formed.

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

[0278] The second electrode 146 can be thinner than the first insulating layer 131. Thus, the step coverage characteristics of the second conductive layer 150 and the second insulating layer 132 surrounding the second electrode 146 can be secured and the reliability of the semiconductor device can be improved. The second electrode 146 can be disposed to be spaced apart from the first insulating layer 131 by a first interval distance S1 of about 1 μm to 4 μm. When the interval distance is greater than or equal to 1 μm, a process margin for disposing the second electrode 146 with respect to the first insulating layer 131 can be secured, thereby improving the electrical characteristics, the optical characteristics, and the reliability of the semiconductor device. When the interval distance is less than or equal to 4 μm, the entire area where the second electrode 146 can be disposed can be secured, and the operating voltage characteristics of the semiconductor device can be improved.

[0279] The second conductive layer 150 can cover the second electrode 146. Thus, the second electrode pad 166, the second conductive layer 150, and the second electrode 146 can form one electrical path.

[0280] The second conductive layer 150 can completely surround the second electrode 146 and can be in contact with one side surface and an upper surface of the first insulating layer 131. The second conductive layer 150 can be made of a material having good adhesion with 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 an alloy thereof. Also, the second conductive layer 150 can be formed as a single layer or a plurality of 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 the electrical reliability of the second electrode 146 can be enhanced. The second conductive layer 150 can extend to a lower portion of the first insulating layer 131. In this case, the detachment of the end portion of the first insulating layer 131 can be suppressed. Thus, the penetration of external moisture or contaminants can be prevented. In addition, the second conductive layer 150 can have a reflection function for reflecting light emitted from a gap between the first insulating layer 131 and the second electrode 146 upward.

[0282] The second conductive layer 150 can be disposed at the first interval distance S1 between the first insulating layer 131 and the second electrode 146. That is, the second conductive layer 150 can be disposed at the first interval distance S1 to contact 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, one region in which the second conductive semiconductor layer 126 contacts the second conductive layer 150 to form a Schottky junction can be disposed within the first interval distance S1. By forming the Schottky junction, current distribution can be facilitated. However, the present application is not limited thereto, and the arrangement can be freely made 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 can electrically insulate the second electrode 146 and the second conductive layer 150 from the first conductive layer 165. The first conductive layer 165 can 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 can 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 above 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 can be prevented.

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

[0286] However, according to an embodiment, the second insulating layer 132 is separately disposed above the first insulating layer 131, and thus, a defect formed in the first insulating layer 131 is difficult 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 the defect.

[0287] Referring again to ​ , the second conductive layer 150 can electrically connect the second electrode to the second electrode pad 166.

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

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

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

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

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

[0293] The substrate 170 can include one material selected from a group of materials including silicon, molybdenum, tungsten, copper, and aluminum or an alloy thereof.

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

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

[0296] ​ is a conceptual view of a semiconductor device according to another embodiment of the present application, ​ is ​ a plan view of

[0297] Referring to ​ , the above-described structure can be equally applied to the semiconductor structure 120. Also, a plurality of grooves 128 can be disposed 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 can include a side reflector Z1 disposed on an edge thereof. The side reflector Z1 can be formed of the second conductive layer 150, the first conductive layer 165, and the substrate 170 protruding in the thickness direction (Y-axis direction). Referring to ​ , the side reflector Z1 can be disposed along the 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 reflect light emitted from the active layer 126 upward. Thus, without forming a separate reflective layer, light emitted in the horizontal direction (X-axis direction) can be reflected upward at the outermost portion thereof due to the TM mode.

[0300] The slope angle of the side reflector Z1 can be greater than 90 degrees and less than 145 degrees. The slope angle can be an angle of the second conductive layer 150 with respect to the horizontal plane (i.e., the XZ plane). When the angle is less than 90 degrees or greater than 145 degrees, the efficiency of light traveling toward the side surface to be reflected upward can be reduced.

[0301] ​ is a conceptual view of a semiconductor device package according to an embodiment of the present application, ​ is a plan view of a semiconductor device package according to an embodiment of the present application, ​ is ​ a variation of ​ is a sectional view of a semiconductor device package according to another embodiment of the present application.

[0302] Referring to ​The semiconductor device package can include a main body 2 having a groove (i.e., an opening) 3, a semiconductor device 1 disposed in the main body 2, and a pair of lead frames 5a and 5b disposed in the main body 2 and electrically connected to the semiconductor device 1. The semiconductor device 1 can include all of the above-described elements.

[0303] The main body 2 can include a UV light reflecting material or a coating layer. The main body 2 can be formed by stacking a plurality of layers 2a, 2b, 2c, 2d, and 2e. The plurality of layers 2a, 2b, 2c, 2d, and 2e can be made of the same material or include different materials. For example, the plurality of layers 2a, 2b, 2c, 2d, and 2e can include aluminum.

[0304] The groove 3 can have a width that increases away from the semiconductor device and have a sloped surface in which a stepped portion 3a is formed.

[0305] The light-transmitting layer 4 can cover the groove 3. The light-transmitting layer 4 can be made of glass, but is not limited thereto. The material of the light-transmitting layer 4 is not limited as long as it can effectively transmit UV light. The space formed in the groove 3 can be empty.

[0306] Referring to ​ The semiconductor device 10 can 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 can be disposed to surround the side surface of the first lead frame 5a.

[0307] Referring to ​ A plurality of semiconductor devices 10a, 10b, 10c, and 10d can be disposed in the semiconductor device package. In this case, the lead frames can 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 disposed on the first lead frame 5a and connected to the second lead frame 5b through a wire. The second semiconductor device 10b can be disposed on the second lead frame 5b and connected to the third lead frame 5c through a wire. The third semiconductor device 10c can be disposed on the third lead frame 5c and connected to the fourth lead frame 5d through a wire. The fourth semiconductor device 10d can be disposed on the fourth lead frame 5d and connected to the fifth lead frame 5e through a wire.

[0309] Referring to ​ The semiconductor device package can include a main 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 body 10 can be manufactured by processing an aluminum substrate. Accordingly, the body 10 according to the embodiment can have inner and outer surfaces both of which are electrically conductive. Such a structure has various advantages. When a non-conductive material such as AlN and Al2O3 is used for the body 10, the reflectivity in the ultraviolet wavelength band is only 20% to 40%. Accordingly, a separate reflective member needs to be provided. Also, a separate circuit pattern and a conductive member such as a lead frame can be needed. Accordingly, the production cost can be increased and the process can be complicated. Also, a conductive member such as gold (Au) absorbs ultraviolet light, and thus the light extraction efficiency is reduced.

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

[0312] The body 10 can include a first conductive part 10a and a second conductive part 10b. A first insulating part 42 can be provided between the first conductive part 10a and the second conductive part 10b. Since both the first conductive part 10a and the second conductive part 10b are electrically conductive, the first insulating part 42 needs to be provided to separate the magnetic poles.

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

[0314] The second insulating part 41 can be made of the same material as that of the first insulating part 42, but is not limited thereto. Each of the first insulating part 42 and the second insulating part 41 can be made of one material selected from various materials including an epoxy molding compound (EMC), white silicon, a photo solder resist (PSR), a silicone resin composition, a modified epoxy resin composition (e.g., a silicon-modified epoxy resin), a modified silicone resin composition (e.g., an epoxy-modified silicone resin), a polyimide resin composition, a modified polyimide resin composition, polyphthalamide (PPA), a polycarbonate resin, polyphenylene sulfide (PPS), a liquid crystal polymer (LCP), an acrylonitrile butadiene styrene (ABS) resin, a phenol resin, an acrylic resin, and a polybutylene terephthalate (PBT) resin.

[0315] According to one embodiment, the second insulating member 41 is provided at the lower edge of the body 10, thus preventing burrs from occurring at the edge when the package is cut. Burrs can occur more frequently in the case of an aluminum substrate than in the case of other metal substrates. When burrs occur, the lower surface 12 can not be flat, making it difficult to mount. In addition, when burrs occur, the thickness can become uneven and measurement errors can occur.

[0316] The third insulating member 43 can be provided at the lower surface 12 of the body 10 and connected with 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 can be provided on the same plane.

[0317] ​ is a conceptual view of a light emitting structure according to an embodiment of the present application, ​ is a graph showing an aluminum composition of a semiconductor structure according to an embodiment of the present application.

[0318] Referring to ​ , the semiconductor device according to the embodiment includes a light emitting structure 120A including a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, and an active layer 126. Each semiconductor layer can have the same configuration as the structure described above. ​

[0319] Referring to ​ , the first conductive semiconductor layer 124, the active layer 126, the barrier layer 129, and the second conductive semiconductor layer 127 can all include aluminum.

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

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

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

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

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

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

[0326] The first intermediate layer S10 can be the first barrier layer 126b. Accordingly, the thickness of the first intermediate layer S10 can be the same as the thickness of the adjacent barrier layer 126b. For example, the thickness of the first intermediate layer S10 can be 2 nm to 10 nm. However, the present application is not limited thereto, and the first intermediate layer S10 can be a portion of the barrier layer 129 or a separate semiconductor layer provided between the first barrier layer 126b and the barrier layer.

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

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

[0329] The 3-2 portion S12 can be thinner than the 3-1 portion S11. The thickness of the 3-2 portion S12 can be about 0.1 nm to about 4 nm. When the thickness of the 3-2 portion S12 is less than 0.1 nm, it can be impossible to block the movement of electrons. When the thickness of the 3-2 portion S12 is greater than 4 nm, the efficiency of injecting holes into the active layer can be reduced.

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

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

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

[0333] Referring to ​ , the structure already described with reference to ​ may be equally applied except for the second intermediate layer S20. The second intermediate layer S20 can be a portion of the barrier layer 129, but is not limited thereto.

[0334] The aluminum composition of the second intermediate layer S20 can 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 can be in the range of 50% to 80%.

[0335] The second intermediate layer S20 can include a 4-1 portion S21 containing no p-type dopant and a 4-2 portion S22 containing a p-type dopant.

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

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

[0338] The thickness of the 4-2 portion S22 can 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 can be difficult to suppress diffusion of the dopant. The ratio of the thickness of the 4-1 portion S21 to the thickness of the 4-2 portion S22 can be in the range of 19:1 to 1:1.5.

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

[0340] Referring to ​ It can be seen that the light output power of the semiconductor device having the conventional light emitting structure is reduced by 20% after about 100 hours. Also, it can be seen that the light output power is reduced by 25% after about 500 hours.

[0341] On the other hand, referring to ​ It can be seen that the light emitting intensity of the semiconductor device having the light emitting structure according to the embodiment is 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 the light output power is increased by about 20% compared to the conventional structure without the intermediate layer according to the embodiment.

[0342] ​ is a graph showing an aluminum composition of a light emitting structure according to still another embodiment of the present application.

[0343] Referring to ​ , the second conductive semiconductor layer 129 can 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 can 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, and thus the current injection efficiency can be reduced. When the thickness of the 2-1 conductive semiconductor layer 127a is greater than 200 nm, the resistance increases in the vertical direction, and thus the current injection efficiency can be reduced.

[0345] The aluminum composition of the 2-1 conductive semiconductor layer 127a can be lower than that of the well layer 126a. To generate ultraviolet light, the aluminum composition of the well layer 126a can 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 the light extraction efficiency can be reduced.

[0346] The aluminum composition of the 2-1 conductive semiconductor layer 127a can be greater than 40% and less than 80%. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is less than 40%, light can be absorbed. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is greater than 80%, the current injection efficiency can be reduced. 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 can be equal to 40%.

[0347] The aluminum composition of the 2-2 conductive semiconductor layer 127a can 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 ohmic-contacted due to the increased resistance therebetween, and the current injection efficiency is also reduced.

[0348] The aluminum composition of the 2-2 conductive semiconductor layer 127a can be greater than 1% and less than 50%. When the aluminum composition is greater than 50%, the 2-2 conductive semiconductor layer 127a can not be sufficiently ohmic-contacted with the p-ohmic electrode. When the aluminum composition is less than 1%, the composition of the 2-2 conductive semiconductor layer 127a can approach GaN, and thus light is absorbed.

[0349] The thickness of the 2-2 conductive semiconductor layer 127a can be greater than about 1 nm and less than about 30 nm. As described above, the 2-2 conductive semiconductor layer 127a contains a very low aluminum composition such that it can be ohmic, and thus can absorb ultraviolet light. Therefore, it can be more advantageous in terms of light output power 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 can not be provided in some portions, and there can 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 light absorbed is so great that the light output power efficiency can be decreased.

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

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

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

[0354] However, the present application is not limited thereto, and the aluminum composition of the first sub-layer 127e can be adjusted on the basis of considering the current injection characteristics and the light absorption rate. Alternatively, the aluminum composition can be adjusted according to the light output power required by a product.

[0355] For example, when the current injection characteristics are 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 characteristics are more important than the electrical characteristics of a product, the aluminum composition of the first sub-layer 127e can be adjusted to be in the range of 1% to 20%.

[0356] When the aluminum composition of the first sub-layer 127e is greater than 1% and less than 20%, the operating voltage can be decreased due to the decrease in the resistance between the first sub-layer 127e and the second electrode. Thus, the electrical characteristics can be enhanced. The thickness of the first sub-layer 127e can be greater than 1 nm and less than 10 nm. Thus, the light absorption problem can be alleviated.

[0357] The thickness of the 2-2 conductive semiconductor layer 127a can be less 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 can 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, and thus the current injection efficiency can be decreased. When the thickness ratio is greater than 20:1, the 2-2 conductive semiconductor layer 127a is too thin, and thus the ohmic reliability can be decreased.

[0358] The aluminum content of the conductive semiconductor layer 127a can decrease with increasing distance from the active layer 126. Furthermore, the aluminum content of the conductive semiconductor layer 127a can decrease with increasing distance from the active layer 126. Therefore, the aluminum content of the first sublayer 127e can satisfy a range of 1% to 10%.

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

[0360] In this case, the degree of reduction in aluminum content of the 2-2 conductive semiconductor layer 127a can be greater than the degree of reduction in aluminum content of the 2-1 conductive semiconductor layer 127a. That is, the change in aluminum content of the 2-2 conductive semiconductor layer 127a in the thickness direction can be greater than the change in aluminum content of the 2-1 conductive semiconductor layer 127a in the thickness direction. Here, the thickness direction can refer to the direction from the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127 or the 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 its aluminum content is higher than that of the well layer 126a. Therefore, the aluminum content of the 2-1 conductive semiconductor layer 127a can be reduced relatively slowly.

[0362] However, the thickness of the 2-2 conductive semiconductor layer 127a is relatively small, resulting in a greater variation in the aluminum composition. Therefore, the reduction in the aluminum composition of the 2-2 conductive semiconductor layer 127a is relatively significant.

[0363] ​ This is a conceptual view of a light-emitting structure grown on a substrate. ​ This is a diagram illustrating the substrate separation process. ​ This is a diagram showing the process of etching the light-emitting structure, and ​ This is a diagram showing the fabricated semiconductor device.

[0364] See ​ The buffer layer 122, the light absorption 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 can be sequentially formed on the growth substrate 121.

[0365] In this case, the first and second intermediate layers can be grown between the active layer 126 and the barrier layer 129. The first barrier layer can 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 can be grown to have a 2-1 portion that is not doped with a p-type dopant and a 2-2 portion that is doped with a dopant.

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

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

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

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

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

[0371] To absorb laser light having a wavelength of 246 nm, the first light absorption layer 123a can be thicker than the second light absorption layer 123b. The thickness of the first light absorption layer 123a can be in the range of 1 nm to 10 nm, and the thickness of the second light absorption layer 123b can 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 can 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 sufficiently absorb the laser light. When the thickness ratio is greater than 6: 1, the second light absorbing layer 123b is too thin, making it possible to reduce the total aluminum component of the light absorbing layer.

[0373] The total thickness of the light absorbing layer 123 can 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 sufficiently absorb the 246 nm laser light. When the thickness is greater than about 400 nm, the total aluminum component is reduced, thus the crystallinity can be poor.

[0374] According to an embodiment, the crystallinity can be enhanced by forming the light absorbing layer 123 with a superlattice structure. Due to this structure, the light absorbing layer 123 can serve as a buffer layer for relieving the lattice mismatch between the growth substrate 121 and the light emitting structure 120.

[0375] Referring to ​ The step of removing the growth substrate 121 can include separating the growth substrate 121 by emitting laser light LI from the side on which the growth substrate 121 is located. The laser light LI can have a wavelength band that can be absorbed by the first light absorbing layer 123a. For example, the laser light can be a KrF laser light having a wavelength band of 248 nm.

[0376] The band gap of the growth substrate 121 and the second light absorbing layer 123b is too high to absorb the laser light LI. However, the first light absorbing layer 123a containing a lower aluminum component can be decomposed by absorbing the laser light LI. Accordingly, 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 can be removed through a marking process.

[0378] Referring to ​ After the second conductive layer 150 is formed over the second conductive semiconductor layer 127, a plurality of recesses 128 can be formed to pass upward through a portion of the first conductive semiconductor layer 124 of the light emitting structure 120. Subsequently, the insulating layer 130 can be formed on one side of the recesses 128 and over the second conductive semiconductor layer 127. Subsequently, the first electrode 142 can be formed on the first conductive semiconductor layer 124b exposed by the recesses 128.

[0379] Referring to ​ The first conductive layer 165 can be formed under the insulating layer 130. The first conductive layer 165 can be electrically insulated from the second conductive layer 150 by the insulating layer 130.

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

[0381] The semiconductor device can be applied to various light source apparatuses. For example, the light source apparatuses can include, conceptually, a sterilization apparatus, a curing apparatus, an illumination apparatus, a display apparatus, and a car lamp. That is, the semiconductor device can be applied to various electronic apparatuses that provide light by being disposed in housings thereof.

[0382] The sterilization apparatus can sterilize a desired area by disposing the semiconductor device according to an embodiment. The sterilization apparatus can be applied to home appliances such as a water purifier, an air conditioner, and a refrigerator, but is not limited thereto. That is, the sterilization apparatus can be applied to various products (e.g., medical devices) that need to be sterilized.

[0383] For example, the water purifier can sterilize circulating water by disposing the sterilization apparatus according to an embodiment. The sterilization apparatus can be disposed at a nozzle or a discharge port through which water circulates, and be configured to emit ultraviolet light. In this case, the sterilization apparatus can include a waterproof structure.

[0384] The curing apparatus can cure various liquids by disposing the semiconductor device according to an embodiment. Conceptually, the liquids can include various materials that are cured when ultraviolet light is emitted. For example, the curing apparatus can cure various types of resin. Alternatively, the curing apparatus can also be used to cure a beauty product such as a manicure product.

[0385] The illumination apparatus can include a light source module including a substrate and a semiconductor device according to an embodiment. The illumination apparatus can 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 from an external source and provide the electrical signal to the light source module. Also, the illumination apparatus can include a lamp, a headlamp, or a street lamp.

[0386] The display apparatus can include a bottom cover, a reflection 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 reflection plate, the light emitting module, the light guide plate, and the optical sheet can constitute a backlight unit.

[0387] The reflection plate can be disposed on the bottom cover, and the light emitting module can emit light. The light guide plate can be disposed in front of the reflection plate to guide the light emitted from the light emitting module forward. The optical sheet can include a prism sheet or the like, and can be disposed in front of the light guide plate. The display panel can be disposed in front of the optical sheet. The image signal output circuit can provide an image signal to the display panel. The color filter can 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 can be used as an edge type backlight unit or a direct type backlight unit.

[0389] The semiconductor device can be a laser diode, rather than the light emitting diode described above.

[0390] Like the light emitting device, the laser diode can include the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer having the structure described above. The laser diode can also utilize an electroluminescence phenomenon in which light is emitted when a current flows after a p-type first conductive semiconductor and an n-type second conductive semiconductor are joined to each other, but there is a difference 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 can be used in optical communication equipment, medical equipment, semiconductor processing equipment, etc.

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

[0392] In general, a semiconductor device such as a photodetector can be manufactured using a direct bandgap semiconductor having a high photoelectric conversion efficiency. Alternatively, the photodetector can have various structures. As the most common structure, the photodetector can include a pin-type photodetector using a p-n junction, a Schottky photodetector using a Schottky junction, a metal-semiconductor-metal (MSM) photodetector, etc.

[0393] Like the light emitting device, the photodiode can include the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer having the structure described above, and can be formed in a p-n junction or a pin structure. The photodiode operates when a reverse bias or zero bias is applied. When light is incident to the photodiode, electrons and holes are generated so that a current flows. In this case, the magnitude of the current can be approximately proportional to the intensity of the light incident to the photodiode.

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

[0395] Further, the solar cell can be used as a rectifier of an electronic circuit by using a rectifying property of a general diode of a p-n junction, and can be applied to an oscillation circuit of a microwave circuit or the like.

[0396] Further, the above semiconductor device does not necessarily have to be implemented only with a semiconductor. Depending on the case, the semiconductor device can also include a metallic material. For example, the semiconductor device such as a light-receiving device can be implemented using at least one of Ag, Al, Au, In, Ga, N, Zn, Se, P, and As, and can be implemented using an intrinsic semiconductor material or a semiconductor material doped with a p-type dopant or an n-type dopant.

[0397] While the present application has been described with reference to exemplary embodiments, the embodiments are merely examples and do not limit the present application. It is understood that various modifications and applications can be made in keeping with the essential characteristics of the embodiments without departing from the spirit and scope of the application. For example, the elements described in detail in the above embodiments can be modified and implemented. Further, differences related to these modifications and applications should be understood as included in the scope of the present application defined by the appended claims.

Claims

1. A semiconductor device, comprising: The light-emitting structure includes: First semiconductor layer; The second semiconductor layer; and An active layer containing aluminum and disposed between the first semiconductor layer and the second semiconductor layer; When primary ions bombard the light-emitting structure and sputter secondary ions containing aluminum from the first semiconductor layer, the active 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, and the second semiconductor layer. The first intensity position exhibits the maximum intensity in the second semiconductor layer, and its intensity is the first intensity; The third intensity position exhibits the minimum intensity across the entire region of the light-emitting structure, and its intensity is the third intensity. The fourth intensity position exhibits the lowest intensity in the first semiconductor layer, and its intensity is the fourth intensity; The second intensity position is located at a position separate from the first intensity, and is the position of the maximum peak intensity in the region between the first intensity and the fourth intensity; its intensity is the second intensity. The fifth intensity position is located between the second intensity position and the fourth intensity position, and its intensity is the fifth intensity, and the magnitude of the fifth intensity is between the second intensity and the fourth intensity; Wherein, 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; The second semiconductor layer includes a second region having a secondary ion strength between the first strength and the third strength. The active layer includes a third region having a secondary ion intensity between the first intensity and the second intensity. Wherein, the first direction is the thickness direction of the light-emitting structure, and is the direction from the second semiconductor layer to the first semiconductor layer.

2. The semiconductor device according to claim 1, wherein, The ratio of the fourth strength to the second strength is in the range of 1:1.2 to 1:2.

5.

3. The semiconductor device according to claim 1, wherein, The ratio of the second strength to the first strength is in the range of 1:1.1 to 1:

2.

4. The semiconductor device according to claim 1, wherein, The ratio of the third strength to the fourth strength is in the range of 1:1.1 to 1:

2.

5. The semiconductor device according to claim 1, wherein, The ratio of the fifth strength to the second strength is in the range of 1:1.1 to 1:2.

0.

6. The semiconductor device according to claim 1, wherein, The ratio of the fourth strength to the fifth strength is in the range of 1:1.1 to 1:2.

0.

7. The semiconductor device according to claim 1, further comprising: The tenth intensity position is located between the first intensity position and the third intensity position, and its intensity is the tenth intensity, and the magnitude of the tenth intensity is the same as the magnitude of the minimum ion intensity in the region between the first intensity position and the second intensity position.

8. The semiconductor device according to claim 7, wherein, The ratio of the tenth strength to the first strength is in the range of 1:1.3 to 1:2.

5.

9. The semiconductor device according to claim 7, wherein, The region between the tenth intensity position and the third intensity position has a thickness of 1 nm to 30 nm.

10. The semiconductor device according to claim 1, wherein, The second semiconductor layer includes a P-type semiconductor layer and an electron blocking layer. The electron blocking layer includes a 1-1 portion and a 1-2 portion. The first intensity position is located in the 1-1 portion, and the thickness of the 1-1 portion is 0.1 nm to 4 nm.

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

12. The semiconductor device according to claim 1, wherein, The second semiconductor layer includes a P-type semiconductor layer and an electron blocking layer, wherein the P-type semiconductor layer comprises an aluminum semiconductor layer whose slope decreases with distance from the active layer.

13. A semiconductor device, comprising: The light-emitting structure includes: First semiconductor layer; The second semiconductor layer; and An active layer containing aluminum and disposed between the first semiconductor layer and the second semiconductor layer; When primary ions bombard the light-emitting structure and sputter secondary ions containing aluminum from the first semiconductor layer, the active 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, and the second semiconductor layer. The first intensity position exhibits the maximum intensity in the second semiconductor layer, and its intensity is the first intensity; The third intensity position exhibits the minimum intensity across the entire region of the light-emitting structure, and its intensity is the third intensity. The fourth intensity position exhibits the lowest intensity in the first semiconductor layer, and its intensity is the fourth intensity; The second intensity position is located at a position separate from the first intensity, and is the position of the maximum peak intensity in the region between the first intensity and the fourth intensity; its intensity is the second intensity. The tenth intensity position, located between the first intensity position and the third intensity position, has an intensity of tenth intensity. Furthermore, the magnitude of the tenth intensity is the same as the magnitude of the minimum ion intensity in the region between the first intensity position and the second intensity position; The region between the tenth intensity position and the third intensity position has a thickness of 1 nm to 30 nm.

14. The semiconductor device according to claim 13, wherein, The ratio of the tenth strength to the first strength is in the range of 1:1.3 to 1:2.

5.

15. The semiconductor device according to claim 13, wherein, The average change in aluminum ion intensity between the tenth intensity position and the third intensity position is greater than the average change in aluminum ion intensity between the first intensity position and the tenth intensity position.

16. The semiconductor device according to claim 13, wherein, The region between the tenth intensity position and the third intensity position has a reverse portion; In the region between the tenth intensity position and the third intensity position, the intensity of aluminum-containing secondary ions generally decreases along the direction from the tenth intensity position to the third intensity position; in the reverse portion, the intensity of aluminum-containing secondary ions increases or remains unchanged along the direction from the tenth intensity position to the third intensity position.

17. The semiconductor device according to claim 13, wherein, The ratio of the fourth strength to the second strength is in the range of 1:1.2 to 1:2.

5.

18. The semiconductor device according to claim 13, wherein, The ratio of the second strength to the first strength is in the range of 1:1.1 to 1:

2.

19. The semiconductor device according to claim 13, wherein, The ratio of the third strength to the fourth strength is in the range of 1:1.1 to 1:

2.

20. The semiconductor device of claim 13, further comprising: The first electrode is electrically connected to the first semiconductor layer; as well as The second electrode is electrically connected to the second semiconductor layer; The fourth intensity position is in contact with the first electrode.

21. The semiconductor device according to claim 13, further comprising: The first electrode is electrically connected to the first semiconductor layer; as well as The second electrode is electrically connected to the second semiconductor layer; The third intensity position is in contact with the second electrode.

22. The semiconductor device according to claim 13, wherein, The second semiconductor layer includes a P-type semiconductor layer and an electron blocking layer. The electron blocking layer includes a 1-1 portion and a 1-2 portion. The first intensity position is located in the 1-1 portion, and the thickness of the 1-1 portion is 0.1 nm to 4 nm.

23. The semiconductor device according to claim 13, wherein, The first semiconductor layer includes a first semiconductor layer first sublayer, a first semiconductor layer second sublayer, and a first semiconductor layer third sublayer, wherein the first semiconductor layer second sublayer is disposed between the first semiconductor layer first sublayer and the first semiconductor layer third sublayer.

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

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