Semiconductor device and semiconductor device package including the same

Abstract

Embodiments of the present application disclose a semiconductor device and a semiconductor device package including the same. The semiconductor device includes: a light-emitting structure including a first-conductive semiconductor layer, a second-conductive semiconductor layer, and an active layer, the active layer being disposed between the first-conductive semiconductor layer and the second-conductive semiconductor layer; the second-conductive semiconductor layer having a ratio of a second shortest distance W2 to a first shortest distance W1 in a range of 1:1.25 to 1:100, the second shortest distance W2 being the distance from a first surface to a second point, and the first shortest distance W1 being the distance from the first surface to a first point; the first surface being the surface of the second semiconductor layer away from the active layer; the first point being the point at which the aluminum composition of the second-conductive semiconductor layer is the same as the aluminum composition of the well layer closest to the second-conductive semiconductor layer of the active layer; and the second point being the point at which the second-conductive semiconductor layer has the same dopant composition as the aluminum composition.

Description

[0001] This application is a divisional application of a patent application for an invention titled "Semiconductor Device and Semiconductor Device Package Including the Same", with an international filing date of September 13, 2017, an international application number of PCT / KR2017 / 010065, and a national stage entry application number in China of 201780056302.2.

[0002] Cross - reference to related applications

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

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

[0005] Semiconductor devices including compounds such as GaN and AlGaN have many advantages such as an adjustable wide - bandgap energy and can thus 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 group compound semiconductors or light - emitting devices such as laser diodes can emit light of various colors, such as red, green, blue, and ultraviolet light, and can also achieve highly efficient white light by using fluorescent materials or combining colors. Compared with conventional light sources such as fluorescent lamps and incandescent lamps, these light - emitting devices also have advantages such as low power consumption, semi - permanent life, fast response speed, safety, and environmental friendliness.

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

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

[0009] Specifically, light-emitting devices that emit light in the ultraviolet wavelength range can be used for curing, medical, and disinfection purposes due to their curing or disinfection effects.

[0010] Recently, research on ultraviolet light-emitting devices has been actively carried out, but it is difficult to vertically fabricate ultraviolet light-emitting devices, and the crystallinity also decreases during the substrate separation process. Summary of the Invention

[0011] Technical Problem

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

[0013] An embodiment also provides a light-emitting device with enhanced light output power.

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

[0015] Solution

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

[0017] Advantageous Effects of the Invention

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

[0041] Figure 16a and Figure 16b is a diagram showing a configuration in which the optical output power increases as the number of grooves increases;

[0042] Figure 17 is Figure 15 an enlarged view of part A of

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

[0044] Figure 19 is Figure 18 a plan view of

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

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

[0047] Figure 22 is Figure 21 a variant of

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

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

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

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

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

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

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

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

[0056] Figure 31 is a diagram showing the process of separating a substrate;

[0057] Figure 32 is a diagram showing the process of etching a light-emitting structure; and

[0058] Figure 33 is a diagram showing the fabricated semiconductor device. DETAILED DESCRIPTION

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

[0060] Details described in specific embodiments can be understood as descriptions related to other embodiments, even if not described in such other embodiments, unless otherwise stated or there is a contradiction.

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

[0062] When describing embodiments, if an element is described as being above or below another element, the two elements may be in direct contact with each other, or one or more other elements may be disposed between the two elements. Additionally, the phrase "above or below" used herein may indicate both an upward direction and a downward direction relative to an element.

[0063] Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them.

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

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

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

[0067] See Figure 1 , a semiconductor device according to an embodiment includes a light-emitting structure, the 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 may be made of a III-V or II-VI compound semiconductor and may be doped with a first dopant. The first conductive semiconductor layer 124 may be made of one material selected from a variety of semiconductor materials having an empirical formula of In x1 Al y1 Ga 1-x1-y1 N (0 ≤ x1 ≤ 1, 0 ≤ y1 ≤ 1, and 0 ≤ x1 + y1 ≤ 1) (e.g., GaN, AlGaN, InGaN, InAlGaN, etc.). Moreover, the first dopant may be an n-type dopant, such as Si, Ge, Sn, Se, and Te. When the first dopant is an n-type dopant, the first conductive semiconductor layer 124 doped with the first dopant may be an n-type semiconductor layer.

[0069] The active layer 126 is disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127. The active layer 126 is a layer in which electrons (or holes) injected through the first conductive semiconductor layer 124 are combined with holes (or electrons) injected through the second conductive semiconductor layer 127. Due to the recombination between electrons and holes, the active layer 126 can be transformed into a low energy level and generate light with an ultraviolet wavelength.

[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 II-VI compound semiconductor. Moreover, 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 with the empirical formula In x5 Al y2 Ga 1-x5-y2 N (0 ≤ x5 ≤ 1, 0 ≤ y2 ≤ 1, and 0 ≤ x5 + y2 ≤ 1) or made of a material selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant, such as Mg, Zn, Ca, Sr, and Ba, the second conductive semiconductor layer 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 (prime)) conductive semiconductor layer 127a, a 2-2 (second-secondary-primary) conductive semiconductor layer 127b, and a 2-3 (second-tertiary-primary) conductive semiconductor layer 127c. The aluminum composition of the 2-1 conductive semiconductor layer 127a can be lower than the 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 possibility 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 material selected from the empirical formula In x1 Al y1 Ga 1-x1-y1made of one of a variety of semiconductor materials (e.g., AlGaN, InGaN, InAlGaN, etc.) for N (0 ≤ x1 ≤ 1, 0 ≤ y1 ≤ 1, and 0 ≤ x1 + y1 ≤ 1), but not limited thereto. The first layer 129b with a high aluminum content and the second layer 129a with a low aluminum content can be alternately arranged in the electron blocking layer 129.

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

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

[0077] The electron blocking layer 129 can include a 1-1 portion 129-1 and a 1-2 portion 129-2. The aluminum composition contained in the 1-1 portion 129-1 can increase towards the blocking layer 129. The 1-1 portion 129-1 can have an aluminum composition 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, the movement of electrons may not be effectively blocked. When the thickness of the 1-1 portion 129-1 is greater than 4 nm, the efficiency of hole injection into the active layer 126 may be reduced.

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

[0080] The thickness of the 2-2 conductive semiconductor layer 127b 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 may 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 may 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. In order to generate ultraviolet light, the well layer 126a can have an aluminum composition of about 30% to about 70%. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is lower than that of the well layer 126a, the 2-2 conductive semiconductor layer 127b absorbs light, so it is possible to reduce the light extraction efficiency. However, in order to prevent the deterioration of the crystallinity of the light-emitting structure, the present invention is not limited thereto. For example, in some parts, 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 greater than 40% and less than 80%. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is less than 40%, light may be absorbed. When the aluminum composition of the 2-2 conductive semiconductor layer 127b is greater than 80%, the current injection efficiency may 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, since the resistance between the 2-1 conductive semiconductor layer 127a and the p-ohmic electrode increases, the 2-1 conductive semiconductor layer 127a cannot make good ohmic contact with the p-ohmic electrode, which may reduce the current injection efficiency.

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

[0085] The thickness of the 2-1 conductive semiconductor layer 127a can be from 1 nm to 30 nm or from 1 nm to 10 nm. As described above, the aluminum content in the 2-1 conductive semiconductor layer 127a is very low, enabling it to be ohmic and thus absorb ultraviolet light. Therefore, it may be advantageous to make the 2-1 conductive semiconductor layer 127a 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 may not be provided in some parts, and there may be a region where the 2-2 conductive semiconductor layer 127b is exposed to the outside of the light-emitting structure 120. Additionally, when the thickness is greater than 30 nm, the amount of light absorbed is so large that the light output power efficiency may be reduced.

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

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

[0089] In this case, the degree of reduction in the aluminum content of the 2-1 conductive semiconductor layer 127a can be greater than the degree of reduction in the aluminum content of the 2-2 conductive semiconductor layer 127b. That is to say, the change in the aluminum content of the 2-1 conductive semiconductor layer 127a in the thickness direction can be larger than the change in the aluminum content 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 content it contains is higher than the aluminum content of the well layer 126a. Therefore, the aluminum content of the 2-2 conductive semiconductor layer 127b can be reduced relatively slowly.

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

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

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

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

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

[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, such 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, such that the crystallinity of the second conductive semiconductor layer 127 may decrease or the stress applied to the substrate may increase, thereby changing the wavelength of the 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 part of the active layer closest to the second conductive semiconductor. The range of the first point P11 may be defined by the spectrum measured by SIMS. The range of the first point P11 may be defined as a part of the second conductive semiconductor layer, and the aluminum composition of this second conductive semiconductor layer is the same as that of the well layer of the active layer.

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

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

[0100] During measurement, the unit of the dopant in the second conductive semiconductor layer can vary according to specific circumstances. However, the boundary region between the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b can be within the range of such a point where the region including the inflection point of the aluminum component of the second conductive semiconductor layer intersects with the spectrum of the dopant in 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 invention is not limited thereto. The second point P21 can be a point located within the 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, which may reduce the power consumption efficiency of the semiconductor. When the aluminum component of the second point P21 is greater than 55%, the 2-1 conductive semiconductor layer 127a is too thick, which may reduce the light extraction efficiency. 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 to the second difference H2 can be 1:1.2 to 1:10. The first difference H1 is the 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 is the 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 to the second difference is less than 1:1.2, the change in the aluminum component of the part between the first point P11 and the second point P21 is slow, so it is difficult to reduce the aluminum component of the contact layer. In addition, when the ratio (H1:H2) of the first difference to the second difference is greater than 1:10, the aluminum component changes rapidly, so there is a possibility of increasing the absorption probability of the light emitted from the active layer.

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

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

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

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

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

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

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

[0112] For example, the wavelength of near ultraviolet wavelength light (UV-A) can be 320 nm to 420 nm, the wavelength of far ultraviolet wavelength light (UV-B) can be 280 nm to 320 nm, and the wavelength of 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 component can be expressed as the ratio of the atomic weight of Al to the total atomic weight, and the total atomic weight includes the atomic weight of In, the atomic weight of Ga, and the atomic weight of Al. For example, when the aluminum component is 40% and the Ga component is 60%, the material can be Al 40 Ga 60 N.

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

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

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

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

[0118] The 1-2 conductive semiconductor layer 124c can be arranged 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%, the light extraction efficiency can be improved by reducing the absorption rate of the 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 1-2 conductive semiconductor layer 124c is higher than that of the well layer 126a. Therefore, 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] In addition, when the aluminum composition of the 1-2 conductive semiconductor layer 124c is higher than that of the 1-1 conductive semiconductor layer 124a, due to the difference in refractive index, light can be easily extracted from the active layer 126 to the outside of the semiconductor structure 120. Therefore, 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, after sufficiently ensuring the thickness of the 1-1 conductive semiconductor layer 124a with a high aluminum composition, the intermediate layer 124b is provided. Therefore, the overall crystallinity of the semiconductor structure 120 can be improved.

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

[0125] Moreover, when the intermediate layer 124b contacts the first electrode, the aluminum content of the intermediate layer 124b can be lower than that of the 1-1 conductive semiconductor layer 124a and 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 aluminum content of the intermediate layer 124b can be appropriately adjusted to absorb the laser light emitted onto the semiconductor structure 120 during the LLO process. Therefore, the aluminum content 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 from 200 nm to 300 nm, the intermediate layer 124b can have an aluminum content 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 content of the intermediate layer 124b can be increased to correspond to the wavelength of the LLO laser. For example, the aluminum content 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 that of the well layer 126a, the intermediate layer 124b may not be able to absorb the light emitted from the active layer 126. Therefore, the light extraction efficiency can be improved. According to an embodiment of the present invention, the wavelength of the LLO laser can be less than the wavelength of the light emitted from the well layer 126a. Therefore, the intermediate layer 124b can have an appropriate aluminum content so that the intermediate layer 124b absorbs the LLO laser but does not absorb the light emitted from the well layer 126a.

[0130] The intermediate layer 124b can include a first intermediate layer (not shown) and a second intermediate layer (not shown). The aluminum content of the first intermediate layer is lower than that of the first conductive semiconductor layer 124, and the aluminum content of the second intermediate layer is higher than that of the first conductive semiconductor layer 124. A plurality of first intermediate layers and a plurality of second intermediate layers can be alternately arranged.

[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 combines with a second carrier (hole or electron) injected through the second conductive semiconductor layer 127. When the first carrier (or second carrier) in the conduction band and the second carrier (or first carrier) in the valence band recombine in the well layer 126a of the active layer 126, light with a wavelength corresponding to the energy level difference (bandgap) between the conduction band and the valence band of the well layer 126a can be generated.

[0132] The active layer 126 may have any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure, but is not limited thereto.

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

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

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

[0136] When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, and Ba, the second conductive semiconductor layer 127 doped with the second dopant may be a p-type semiconductor layer. However, the present invention is not limited thereto, and the second conductive semiconductor layer 124 may be an n-type semiconductor layer.

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

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

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

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

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

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

[0143] The aluminum composition contained in the 1-1 portion 129a may 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 may be 80% to 100%. Therefore, the 1-1 portion 129a of the blocking layer 129 may be the portion with the highest aluminum composition in the semiconductor structure 120.

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

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

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

[0148] The 1-3 portion 129b disposed between the 1-1 portion 129a and the 1-2 portion 129c may include an undoped portion that does not contain a dopant. Therefore, the 1-3 portion 129b can be used to prevent the second dopant from diffusing from the second conductive semiconductor layer 127 to the active layer 126.

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

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

[0151] The aluminum component contained in the 2-2 conductive semiconductor layer 127b may be higher than the aluminum component contained in the well layer 126a. In order to generate ultraviolet light, the aluminum component of the well layer 126a may be from about 30% to about 70%. Therefore, the aluminum component of the 2-2 conductive semiconductor layer 127b may be in the 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%, the deterioration of the 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 may be equal to 40%.

[0153] The aluminum component of the 2-1 conductive semiconductor layer 127a may 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 ohmically contacted due to the increased resistance therebetween, and the current injection efficiency will also be reduced.

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

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

[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. In addition, when the thickness is less than or equal to 30 nm, the light output power efficiency can be improved by reducing the amount of light absorbed by the 2-1 conductive semiconductor layer 127a.

[0157] The thickness of the 2-1 conductive semiconductor layer 127a 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 improving the current injection efficiency. In addition, when the thickness ratio is less than 1:20, the thickness of the 2-1 conductive semiconductor layer 127a increases, thereby slowing down the deterioration of crystallinity. When the 2-1 conductive semiconductor layer 127a is too thin, a rapid change in the aluminum composition within the thickness range is required, so the crystallinity can be reduced.

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

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

[0160] The aluminum composition of the 2-1 conductive semiconductor layer 127a can be lower than the aluminum composition of the well layer 126a to achieve a low contact resistance with the second electrode. Therefore, the 2-1 conductive semiconductor layer 127a can absorb a part 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 thickness of the 2-1 conductive semiconductor layer 127a is small but the change in aluminum is relatively large. Therefore, the 2-1 conductive semiconductor layer 127a can have a relatively high degree of reduction in aluminum in terms of thickness.

[0163] On the other hand, the 2-2 conductive semiconductor layer 127b is thicker than the 2-1 conductive semiconductor layer 127a and contains 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 change in the aluminum component in terms of thickness is large, 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 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 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 to reduce the crystallinity of the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127b. When the aluminum component is less than 70%, it is possible to prevent the reduction in crystallinity caused by the rapid change in the aluminum components 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 thickness of the 2-1 conductive semiconductor layer 127a can be 1 nm to 10 nm, the thickness of the 2-2 conductive semiconductor layer 127b can be 10 nm to 50 nm, and the thickness of the 2-3 conductive semiconductor layer 127c can be 20 nm to 60 nm.

[0167] Therefore, the ratio of the thickness of the 2-1 conductive semiconductor layer 127a to the total thickness of the second conductive semiconductor layer 127 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 ensure 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 ensure the optical characteristics (e.g., light output power) of the semiconductor device. However, the present invention is not limited thereto, and the ratio of the thickness of the 2-1 conductive semiconductor layer 127a to the total thickness of the second conductive semiconductor layer 127 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 an embodiment of the present invention may have a first point P1 and a third point P3, where the aluminum component of the semiconductor structure is the highest at the first point P1 and the lowest at the third point P3. Here, the first point P1 may be the 1-1 portion 129a of the barrier layer 129 with the highest aluminum component, and the third point P3 may be the 2-1 conductive semiconductor layer 127a with the lowest aluminum component.

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

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

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

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

[0173] When the aluminum component ratio is greater than or equal to 1:0.5, the aluminum component of the 1-1 conductive semiconductor layer 124a can be increased, thereby improving the crystallinity. When the aluminum component ratio is less than or equal to 1:0.9, the aluminum component of the intermediate layer 124b can be increased, thereby reducing the absorption of ultraviolet wavelength light.

[0174] Figure 11a and Figure 11b shows the SIMS data of the semiconductor structure according to an embodiment of the present invention, Figure 11c and Figure 11d shows the SIMS data of the semiconductor structure according to another embodiment of the present invention,Figure 12 is a graph showing Figures 11a to 11d the aluminum ion intensity, Figure 13a is a graph showing Figure 12 (a) the partially enlarged SIMS data, Figure 13b is a graph showing Figure 12 (b) the SIMS data converted to a linear scale.

[0175] Referring to Figure 11a , the semiconductor structure can have components aluminum (Al), gallium (Ga), a first dopant, a second dopant, oxygen (O), and carbon (C), and these components vary in the 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 invention is not limited thereto.

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

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

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

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

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

[0181] Figures 11a to 11d The aluminum and gallium in the SIMS data ofFigures 11a to 11d Placed in a single figure to represent SIMS data and doping concentration data.

[0182] Referring to Figure 11a , which shows that the spectra of the strength levels of aluminum and the spectra of the concentrations of the first dopant and the second dopant partially intersect each other. However, the data on strength and the data on dopant concentration can have independent relationships.

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

[0184] The measurement methods for the concentrations of the first dopant, the second dopant, oxygen, or carbon are not limited to a specific form. Moreover, in this 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 after the maximum intensity point, the intensity of aluminum ions alternately increases and decreases. Since the material AlGaN is formed by replacing Al atoms with Ga atoms in the GaN-based semiconductor material, the intensity of gallium ions can be symmetric with the intensity of aluminum ions.

[0186] The ion intensity according to the embodiment can increase or decrease according to the measurement conditions. However, the secondary ion intensity (e.g., aluminum 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. Therefore, even if the measurement conditions change, the change in 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 gradually decrease as it moves away from the surface. The second dopant can be present in all regions of the second conductive semiconductor layer and some regions of the active layer, but is not limited thereto. The second dopant can be arranged only in the second conductive semiconductor layer, but can diffuse upward into the active layer. Therefore, the injection efficiency of injecting the second dopant into the active layer can be improved. However, when the second dopant diffuses upward into the first conductive semiconductor layer, leakage current of the semiconductor device and / or non-radiative recombination between the first carrier and the second carrier may occur, thereby reducing the reliability and / or luminous efficiency of the semiconductor device.

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

[0189] It can be confirmed Figures 11b to 11d shows the same trend as Figure 11a the same trend.

[0190] Refer to Figure 12 and Figure 13a , the aluminum ion intensity may include the aluminum ion intensities of the first point to the sixth point P1, P2, P3, P4, P5, and P6. Figure 12 Part (a) in Figure 11a shows the aluminum ion intensity of Figure 12 Part (b) in Figure 11b shows the aluminum ion intensity of Figure 12 Part (c) in Figure 11c shows the aluminum ion intensity of Figure 12 Part (d) in Figure 11d shows the aluminum ion intensity of

[0191] Figure 12 Part (c) in Figure 12 and part (d) in Figure 12 show a distribution similar to the distribution of the aluminum ion intensity in part (a) in Figure 12 except for the concave-convex part P7 where the ion intensity changes between the first point P1 and the third point P3. For example, according to the embodiments of part (c) in Figure 12 and part (d) in

[0192] There is such a structure in which a superlattice layer is further provided on the blocking layer. The aluminum ion intensity of the first point P1 may be the highest in the semiconductor structure 120. Since the aluminum ion intensity of the first point P1 is the highest, non-radiative recombination of the first carriers and the second carriers in the second conductive semiconductor layer can be prevented. Therefore, the light output power of the semiconductor device can be improved. The first point P1 may be a region corresponding to the 1-1 part 129a of the blocking layer 129, but is not limited thereto.

[0193] The secondary ion intensity of the second point P2 may correspond to the point with the highest aluminum ion intensity among the plurality of points with aluminum ion intensity extending along the first direction D (i.e., the direction of increasing depth) from the first point P1.

[0194] The second point P2 can be the point with the highest aluminum ion intensity in the first conductive semiconductor layer 124, and can also be the 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 energy of the first carriers injected into the active layer in the first conductive semiconductor layer 124. Therefore, the light-emitting 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 the point with the lowest aluminum ion intensity in the direction from the first point P1 to the surface of the semiconductor structure 120 (the direction opposite to the first direction).

[0197] When the third point P3 is in contact with the second electrode, since 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. Therefore, the injection efficiency of injecting current into the semiconductor structure 120 through the second electrode can be ensured.

[0198] The fourth ion intensity of the fourth point P4 can correspond to the point with the lowest aluminum ion intensity 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, so that the laser does not penetrate the active layer, thereby preventing damage to the active layer caused by the LLO process.

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

[0201] The fifth point P5 can be set 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 into a single layer. By uniformly distributing the current injected via the fourth point P4 in the layer including the fifth point P5, what can be improved is the uniformity of the current per unit area density injected into the active layer.

[0202] In addition, multiple points (or layers) can be separately provided along the first direction D starting from the fourth point P4, and the aluminum ion intensity of these points (or layers) is the same as or similar to that of the fifth point P5. That is to say, there can be a portion in which the ion intensity increases from the fourth point P4 along the first direction. Therefore, the fourth point P4 can be provided between multiple points (or layers) whose aluminum ion intensity is the same as that of the fifth point P5. However, the present invention is not limited thereto, and the aluminum ion intensity in a region separated from the fifth point P5 in the first direction D and spaced farther than the fourth point P4 in the first direction D can be higher than that 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, and the point S22 is located between the first point P1 and the second point P2 and has the lowest ion intensity.

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

[0205] Moreover, the conductivity of the third point P3 electrically connected to the second electrode can be lower than that of the fourth point P4 connected to the first electrode. Therefore, the ion intensity of the third point P3 can be less than that of the fourth point P4.

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

[0207] The 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 the region S11 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 unchanged 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. Therefore, 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 drops too rapidly, the crystallinity of the second conductive semiconductor layer can be significantly reduced.

[0210] Therefore, during the process of continuously decreasing or increasing the temperature, when the temperature that has been decreased starts to increase, a large amount of aluminum is immediately included, and thus the reverse portion P6 can be formed.

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

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

[0213] See Figure 13a , in the 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 of increasing depth.

[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 along 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 the point with the highest aluminum intensity in the semiconductor structure, the second point P2 can be a point separately disposed in the first direction (the direction of increasing depth) away from the surface on the graph, and the ion intensity of the second point P2 is higher than the maximum ion intensity (peak ion intensity) of the second portion S2.

[0216] However, the present invention is not limited thereto, and the height of the second point 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 the 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 ion intensity ratio M1 of the point at the trough S22 with the lowest ion intensity to the first point P1 can be from 1:0.4 to 1:0.6, and the ion intensity ratio M2 of the trough S22 to the peak S21 can be from 1:0.5 to 1:0.75.

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

[0220] In addition, when the ion intensity 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 can be ensured, and the first point P1 and the third point P3 are set closer to the surface than the active layer.

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

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

[0223] The ratio of the ratio M1 to the ratio M2 can satisfy the range of 1:0.3 to 1:0.8. Therefore, the part where the ratio of the ratio M1 to the ratio M2 satisfies the range of 1:0.3 to 1:0.8 can be the part where the active layer is actually set.

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

[0225] Moreover, the distance between adjacent 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 part S1 may include a surface region S11, and the ionic strength of the surface region S11 is less than that of the fourth point P4. In this case, the ionic strength of the surface region S11 may 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 P1 and the third point P3 may be in the range of 1:1.5 to 1:2.5. When the intensity difference ratio D1:D2 is greater than or equal to 1:1.5 (e.g., 1:1.6), the second intensity difference D2 decreases, and thus the aluminum component at the first point P1 can be sufficiently reduced. Therefore, the contact resistance with the second electrode can be decreased.

[0228] Moreover, when the intensity difference ratio D1:D2 is less than or equal to 1:2.5 (e.g., 1:2.4), it is possible to prevent the light emitted from the active layer 126 from being absorbed by the 2-1 conductive semiconductor layer 127a due to an excessively low aluminum component, thereby preventing deterioration of the optical characteristics of the semiconductor.

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

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

[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 at the third point P3 is not measured or significantly reduced. 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 may deviate from the above ranges.

[0232] The ratio of the intensity difference between the first point P1 and the third point P3 to the intensity difference between the fifth point P5 and the third point P3 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 enhanced. 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 ionic strength ratio of the third point P3 to the first point P1 (P3:P1) can be in the range of 1:2 to 1:4. When the ionic strength ratio of the third point P3 to the first point P1 is greater than or equal to 1:2 (e.g., 1:2.1), the intensity of the third point P3 is greatly reduced, and thus the contact resistance with the second electrode can be decreased. In addition, when the ionic strength ratio of the third point P3 to the first point P1 is less than or equal to 1:4 (e.g., 1:3.9), the aluminum intensity of the third point P3 can be increased. Therefore, light absorption at the third point P3 can be prevented.

[0234] The ionic strength 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 ionic strength ratio of the tenth point P10 to the first point P1 is greater than or equal to 1:1.3, the ionic strength of the first point P1 increases, and thus the first carriers can be effectively prevented from passing through the active layer. When the ionic strength ratio of the tenth point P10 to the first point P1 is less than or equal to 1:2.5, the ionic strength of the tenth point P10 increases, and thus the well layer can generate ultraviolet wavelength light.

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

[0236] The ionic strength 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 ionic strength ratio of the second point P2 to the first point P1 is greater than or equal to 1:1.1, the ionic strength of the first point P1 increases, and thus the first carriers can be effectively prevented from passing through the active layer. In addition, when the ionic strength ratio of the second point P2 to the first point P1 is less than or equal to 1:2, the first carriers and the second carriers that are injected into the active layer and recombine radiatively with each other can reach equilibrium in concentration, and the amount of light emitted by the semiconductor device can be enhanced.

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

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

[0239] The ionic strength 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 ionic strength ratio of the fourth point P4 to the fifth point P5 is greater than or equal to 1:1.1, the ionic strength of the fifth point P5 increases, and thus the crystallinity can be improved. In addition, when the ionic strength ratio of the fourth point P4 to the fifth point P5 is less than or equal to 1:2.0, the ionic strength of the fourth point P4 increases, and thus the absorption rate of ultraviolet wavelength light can be reduced.

[0240] In Figure 12 and Figure 13a the aluminum ionic strength is represented on a logarithmic scale. However, the present invention is not limited thereto, and the aluminum ionic strength can be represented on a linear scale.

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

[0242] For example, the first sub-level of the first order of magnitude can be 1.0×10 1 and the second sub-level of the first order of magnitude can be 2.0×10 1, the third sub-level of the first order of magnitude can be 3.0×10 1 , the ninth sub-level of the first order of magnitude can be 9.0×10 1 , the tenth sub-level of the first order of magnitude can be 1.0×10 2 . That is to say, the tenth sub-level of the first order of magnitude can be equal to the first sub-level of the second order of magnitude. In Figure 13b , the dotted line indicates every two sub-levels.

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

[0244] Refer to Figure 14a , according to an embodiment, the second conductive semiconductor layer 127 may include a 2-1 conductive semiconductor layer 127a, a 2-2 conductive semiconductor layer 127b, and a 2-3 conductive semiconductor layer 127c. The 2-1 conductive semiconductor layer 127a may be a contact layer in contact with the second electrode. The above description can be applied to illustrate the characteristics of these layers.

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

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

[0247] Refer to Figure 14b , it can be seen that the 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 composition of 1% to 10%, so the 2-1 conductive semiconductor layer 127a can be formed in the form of clusters C1 to increase the bonding area. Therefore, the electrical characteristics can be enhanced.

[0248] On the surface of the second conductive semiconductor layer 127, on average, per 1 μm 2 One to eight clusters C1 can be observed. Here, the average value is the average of multiple values measured at about 10 or more different positions. By measuring Figure 14b The result obtained from the position E1 is that 12 clusters C1 are observed per unit area (2 μm × 2 μm). Only the 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 the clusters protruding more than 25 nm from the surface can be output.

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

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

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

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

[0253] Referring to Figure 14d , it can be seen that when the second conductive semiconductor layer is grown at a high speed, the clusters fail to grow well. Therefore, 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 in the range of 1% to 10% on its surface, no clusters C1 are still formed. For example, Figure 14d is a photo obtained by measuring the surface after growing P-AlGaN at a speed of 0.06 nm / s.

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

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

[0256] Figure 15 is a conceptual view of a semiconductor device according to an embodiment of the present invention, Figure 16a and Figure 16b is a diagram showing a configuration in which the optical output power is enhanced as the number of grooves changes, Figure 17 is Figure 15 an enlarged view of part A of

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

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

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

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

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

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

[0263] Compared with a blue GaN-based semiconductor device, an ultraviolet semiconductor device has reduced current diffusion characteristics. Therefore, compared with a blue GaN-based semiconductor device, an ultraviolet semiconductor device needs to have a relatively large number of first electrodes 142 provided therein.

[0264] When the aluminum composition increases, the current diffusion characteristics may deteriorate. See Figure 16a , the current diffuses only at points adjacent to each first electrode 142, and the current density may rapidly decrease at points away from each first electrode 142. Therefore, the effective light-emitting region P2 can be made narrower.

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

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

[0267] Generally, since the GaN semiconductor layer emitting blue light has relatively excellent current spreading characteristics, it is preferable to minimize the areas of the grooves 128 and the first electrodes 142. This is because as the areas of the grooves 128 and the first electrodes 142 increase, the area of the active layer 126 decreases. However, according to the embodiment, since the aluminum component is high, the current spreading characteristics are 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 this reduces the area of the active layer 126) or preferably to dispose a reflective structure in the low current density region P3.

[0268] See Figure 16b , when the number of the grooves 128 increases to 48, the grooves 128 can be arranged in a zigzag form instead of being arranged straight in the 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 may have reduced current spreading characteristics in the semiconductor structure 120. Thus, a smooth current injection is required to ensure uniform current density characteristics in the semiconductor structure 120 and to ensure the electrical and optical characteristics and reliability of the semiconductor device. Therefore, in order to inject current smoothly, a relatively large number of grooves 128 can be formed compared with the GaN-based semiconductor structure 120, and then the first electrodes 142 can be disposed on the grooves 128.

[0270] See Figure 17 , the first insulating layer 131 can electrically insulate the first electrode 142 from the active layer 126 and the second conductive semiconductor layer 127. In addition, the first insulating layer 131 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 side oxidation of the active layer 126 during the process of the semiconductor device.

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

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

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

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

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

[0276] The slope angle θ5 of each groove 128 may be 70 degrees to 90 degrees. When this range is satisfied, this is advantageous for forming the first electrode 142 at 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 be increased, but the area where the first electrode 142 is to be provided can be decreased. Therefore, the current injection characteristics and the light emission efficiency can be reduced. Therefore, the area ratio of the first electrode 142 to the second electrode 146 can be adjusted by using the slope angle θ5 of each groove 128.

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

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

[0280] The second conductive layer 150 can completely surround the second electrode 146 and can be in contact with a 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 to the first insulating layer 131 and is made of at least one material selected from a group of materials including Cr, Al, Ti, Ni, and Au or alloys thereof. Moreover, the second conductive layer 150 can be formed as a single layer or a multilayer.

[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 the lower part of the first insulating layer 131. In this case, the detachment of the end portion of the first insulating layer 131 can be suppressed. Therefore, the penetration of external moisture or contaminants can be prevented. In addition, the second conductive layer 150 can have a reflection function for reflecting upward the light emitted from the gap between the first insulating layer 131 and the second electrode 146.

[0282] The second conductive layer 150 may be disposed at a first spacing distance S1 between the first insulating layer 131 and the second electrode 146. That is, the second conductive layer 150 may be disposed at the first spacing distance S1 and in contact with a side surface and an upper surface of the second electrode 146 and a side surface and an upper surface of the first insulating layer 131. Additionally, a region may be provided within the first spacing distance S1, within which the second conductive semiconductor layer 126 contacts the second conductive layer 150 to form a Schottky junction. By forming the Schottky junction, current distribution can be promoted. However, the present invention is not limited thereto, and arrangements 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 may electrically insulate the second electrode 146 and the second conductive layer 150 from the first conductive layer 165. The first conductive layer 165 may be electrically connected to the first electrode 142 via the second insulating layer 132. The second insulating layer 132 and the first insulating layer 131 may be made of the same material or different materials.

[0284] According to an embodiment, the second insulating layer 132 is disposed between the first electrode 142 and the second electrode 146 and above the first insulating layer 131. 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, defects such as cracks are likely to propagate in the thickness direction. Therefore, external moisture or contaminants may penetrate into the semiconductor structure through the exposed defects.

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

[0287] Referring back to Figure 15 , the second conductive layer 150 may electrically connect the second electrode to the second electrode pad 166.

[0288] The second electrode 146 may be directly disposed on the second conductive semiconductor layer 127. When the second conductive semiconductor layer 127 is made of AlGaN, since the conductivity is low, holes may not be injected smoothly. Therefore, the aluminum composition of the second conductive semiconductor layer 127 needs to be appropriately 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 that includes Cr, Al, Ti, Ni, and Au or their alloys. Moreover, 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 arranged according to the shape of the bottom surface of the semiconductor structure 120 and the groove 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 be used to reflect the light emitted by the active layer 126 upward in the direction toward the substrate, thereby improving the light extraction efficiency. However, the present invention is not limited thereto, and the first conductive layer 165 can provide the function of electrically connecting to the first electrode 142. The first conductive layer 165 may not include a high-reflection material such as aluminum and / or silver (Ag). In this case, a reflective metal layer (not shown) containing a high-reflection material can be provided between the first conductive layer 165 and the first electrode 142 disposed in the groove 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 a material selected from a group of materials that includes gold, tin, indium, aluminum, silicon, silver, nickel, and copper or their alloys.

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

[0293] The substrate 170 can include a material selected from a group of materials that includes silicon, molybdenum, tungsten, copper, and aluminum or their alloys.

[0294] The passivation layer 180 can be provided on the upper surface and one side surface of the semiconductor structure 120. The thickness of the passivation layer 180 can be from 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 the electrical and optical reliability can be improved. When the thickness is less than or equal to 500 nm, the stress applied to the semiconductor device can be reduced, and it can also prevent an increase in semiconductor cost due to a decrease in the optical and electrical reliability of the semiconductor device or an extension of the processing time of the semiconductor device.

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

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

[0297] See Figure 18 , the above structure may be similarly applied to the semiconductor structure 120. Moreover, a plurality of grooves 128 may be formed through the second conductive semiconductor layer 127 and the active layer 126 and disposed in a part of the first conductive semiconductor layer 124.

[0298] The semiconductor device may include a side reflector Z1 disposed on its edge. The side reflector Z1 may be formed of a second conductive layer 150, a first conductive layer 165, and a substrate 170 protruding in the thickness direction (Y-axis direction). See Figure 20 , the side reflector Z1 may 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 further than the active layer 126, so that the second conductive layer 150 can reflect the light emitted by the active layer 126 upward. Therefore, in the case where no separate reflective layer is formed, due to the TM mode, the light emitted in the horizontal direction (X-axis direction) can be reflected upward at its outermost part.

[0300] The slope angle of the side reflector Z1 may be greater than 90 degrees and less than 145 degrees. The slope angle may be the angle of the second conductive layer 150 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 the light traveling toward the side being reflected upward may be reduced.

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

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

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

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

[0305] The light-transmitting layer 4 may cover the groove 3. The light-transmitting layer 4 may be made of glass, but is not limited thereto. There is no limitation on the material of the light-transmitting layer 4 as long as the material can effectively transmit ultraviolet light. The space formed in the groove 3 may be empty.

[0306] See Figure 21 , the semiconductor device 10 may be disposed on the first lead frame 5a and connected to the second lead frame 5b through a wire. In this case, the second lead frame 5b may be disposed to surround the side surface of the first lead frame 5a.

[0307] See Figure 22 , a plurality of semiconductor devices 10a, 10b, 10c, and 10d may be provided in the semiconductor device package. In this case, the lead frame may include a first lead frame 5a, a second lead frame 5b, a third lead frame 5c, a fourth lead frame 5d, and a fifth lead frame 5e.

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

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

[0310] The main body 10 can be manufactured by processing an aluminum substrate. Thus, the main body 10 according to the embodiment can have an inner surface and an outer surface that are both conductive. This structure has various advantages. When non-conductive materials such as AlN and Al2O3 are used for the main body 10, the reflectance in the ultraviolet wavelength band is only 20% to 40%. Therefore, a separate reflecting member needs to be provided. Moreover, a separate circuit pattern and conductive members such as lead frames may be required. As a result, the production cost may increase and the process may be complicated. Also, conductive members such as gold (Au) absorb ultraviolet light, thus reducing the light extraction efficiency.

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

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

[0313] The main 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 member 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 member 41 can be made of the same material as that of the first insulating member 42, but is not limited thereto. Each of the first insulating member 42 and the second insulating member 41 can be made of a material selected from the following various materials: epoxy molding compound (EMC), white silicon, photoimageable solder resist (PSR), silicone resin composition, modified epoxy resin composition (such as silicone-modified epoxy resin), modified silicone resin composition (such as epoxy-modified silicone resin), polyimide resin composition, modified polyimide resin composition, polyphthalamide (PPA), polycarbonate resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), acrylonitrile butadiene styrene (ABS) resin, phenolic resin, acrylic resin, and polybutylene terephthalate PBT resin.

[0315] According to one embodiment, a second insulating member 41 is provided at the lower edge of the main body 10, thereby preventing burrs from appearing at the edge during the cutting of the package. Compared with other metal substrates, burrs may appear more frequently on the aluminum substrate. When burrs appear, the lower surface 12 may be uneven, making it impossible to install well. In addition, when burrs appear, the thickness may become uneven and measurement errors may occur.

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

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

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

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

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

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

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

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

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

[0325] The first intermediate layer S10 may be provided between the blocking layer 129 and the first well layer 126a of the active layer 126. The first intermediate layer S10 may include a 3-1 part S11 and a 3-2 part S12. The aluminum composition of the 3-1 part S11 is lower than that of the blocking layer 129, and the aluminum composition of the 3-2 part S12 is higher than that of the blocking layer 129.

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

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

[0328] The aluminum composition of the 3-2 portion S12 can be higher than that of the blocking layer 129. The aluminum composition of the 3-2 portion S12 can increase towards the blocking layer 129. The aluminum composition of the 3-2 portion S12 can be in the range of 80% to 100%. That is to say, 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 arranged.

[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 may not be possible 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 may 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 met, the hole injection efficiency may 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, the Mg in the blocking layer 129 can diffuse into a part of the first portion. However, in order to prevent the dopant from diffusing into the active layer 126, at least some regions of the 3-2 portion S12 can include an undoped portion.

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

[0333] See Figure 26 , except for the second intermediate layer S20, the structures already described with reference to Figure 25 can be similarly applied. The second intermediate layer S20 can be a part of the blocking layer 129, but is not limited thereto.

[0334] The aluminum composition of the second intermediate layer S20 can be lower than that of the blocking 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 that does not contain a p-type dopant and a 4-2 portion S22 that contains a p-type dopant.

[0336] The 4-1 part S21 may include an undoped part. Accordingly, dopant diffusion into the active layer 126 can be suppressed during the growth of the blocking layer 129. The thickness of the 4-1 part S21 may be 4 nm to 19 nm. When the thickness of the 4-1 part S21 is less than 4 nm, dopant diffusion can be suppressed. When the thickness of the 4-1 part S21 is greater than 19 nm, hole injection efficiency can be reduced.

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

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

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

[0340] See Figure 27 , it can be seen that the light output power of a semiconductor device having a conventional light-emitting structure is reduced by 20% after about 100 hours. Moreover, it can be seen that after about 500 hours, the light output power is reduced by 25%.

[0341] On the other hand, see Figure 28 , it can be seen that the light emission intensity of a semiconductor device having a 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 with the conventional structure in the case where the intermediate layer according to the embodiment is not provided.

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

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

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

[0345] The aluminum composition of the 2-1 conductive semiconductor layer 127a can be lower than that of the well layer 126a. In order 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, thus reducing the light extraction efficiency.

[0346] The 2-1 conductive semiconductor layer 127a can have an aluminum composition greater than 40% and less than 80%. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is less than 40%, light may be absorbed. When the aluminum composition of the 2-1 conductive semiconductor layer 127a is greater than 80%, the current injection efficiency may decrease. For example, when the aluminum composition of the well layer 126a is equal to 30%, the aluminum composition of the 2-1 conductive semiconductor layer 127a 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 make sufficient ohmic contact 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 may not be able to make sufficient ohmic contact with the p ohmic electrode. When the aluminum composition is less than 1%, the composition of the 2-2 conductive semiconductor layer 127a can be close to GaN, so it absorbs light.

[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 very low aluminum composition contained in the 2-2 conductive semiconductor layer 127a enables it to be ohmicized and thus absorb ultraviolet light. Therefore, in terms of the light output power, it may be more advantageous to make the 2-2 conductive semiconductor layer 127a as thin as possible.

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

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

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

[0353] When the aluminum composition is less than 1%, the first sub-layer 127e may have a 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, thus reducing the current injection efficiency.

[0354] However, the present invention is not limited thereto, and the aluminum composition of the first sub-layer 127e can be adjusted based on consideration of the current injection characteristics and the light absorption rate. Alternatively, the aluminum composition can be adjusted according to the light output power required for the 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 the 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%, since the resistance between the first sub-layer 127e and the second electrode decreases, the operating voltage can be reduced. Therefore, 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. Therefore, 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, so that the current injection efficiency may be reduced. When the thickness ratio is greater than 20:1, the 2-2 conductive semiconductor layer 127a is too thin, thus reducing the ohmic reliability.

[0358] The aluminum composition of the 2-1 conductive semiconductor layer 127a can decrease as it moves away from the active layer 126. Moreover, the aluminum composition of the 2-2 conductive semiconductor layer 127a can decrease as it moves away from the active layer 126. Therefore, the aluminum composition of the first sublayer 127e can satisfy the 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 some portions in which the aluminum composition of the 2-1 conductive semiconductor layer 127a and the 2-2 conductive semiconductor layer 127a does not decrease, rather than the aluminum composition continuously decreasing.

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

[0362] However, the 2-2 conductive semiconductor layer 127a has a smaller thickness and a larger change in the aluminum composition. Therefore, the degree of decrease in the aluminum composition of the 2-2 conductive semiconductor layer 127a is relatively high.

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

[0364] See Figure 30 , 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 may be sequentially formed on the growth substrate 121.

[0365] In this case, the first intermediate layer and the second intermediate layer 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 and a 1-2 portion, the 1-1 portion having an aluminum composition of 50% to 70%, and the 1-2 portion having an aluminum composition of 80% to 100%. Moreover, the second intermediate layer can be grown to have a 2-1 portion that is undoped 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 with a low aluminum composition and a second light absorption layer 123b with a high aluminum composition. A plurality of first light absorption layers 123a and a plurality of second light absorption layers 123b can be alternately arranged.

[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 during a laser lift-off (LLO) process when absorbing a laser. Thus, 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 a laser 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 123 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 a laser with 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 absorption layer 123a to the second light absorption 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 absorption layer 123a is too thin, making it difficult to fully absorb the laser. When the thickness ratio is greater than 6:1, the second light absorption layer 123b is too thin, which may reduce the total aluminum composition of the light absorption layer.

[0373] The total thickness of the light absorption 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 absorption layer 123a is too thin, making it difficult to fully absorb the 246-nm laser. When the thickness is greater than about 400 nm, the total aluminum composition decreases, and thus the crystallinity may deteriorate.

[0374] According to the embodiment, the crystallinity can be enhanced by forming the light absorption layer 123 with a superlattice structure. Due to this structure, the light absorption layer 123 can be used as a buffer layer to relieve the lattice mismatch between the growth substrate 121 and the light-emitting structure 120.

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

[0376] The energy band gaps of the growth substrate 121 and the second light absorption layer 123b are too high to absorb the laser L1. However, the first light absorption layer 123a containing a lower aluminum composition can be decomposed by absorbing the laser L1. Therefore, the first light absorption layer 123a can be separated together with the growth substrate 121.

[0377] Subsequently, the residual light absorption layer 123-2 on the first conductive semiconductor layer 124 can be removed by a marking process.

[0378] See Figure 32 , after the second conductive layer 150 is formed above the second conductive semiconductor layer 127, a plurality of grooves 128 can be formed to penetrate upward through a part 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 grooves 128 and above the second conductive semiconductor layer 127. Subsequently, the first electrode 142 can be formed on the first conductive semiconductor layer 124b exposed by the grooves 128.

[0379] See Figure 33 , the first conductive layer 165 can be formed below the insulating layer 130. The first conductive layer 165 can be electrically insulated from the second conductive layer 150 through 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 a mesa etching process.

[0381] The semiconductor device can be applied to various light source devices. For example, conceptually, the light source device can include a disinfection device, a curing device, a lighting device, a display device, and a vehicle headlight. That is, the semiconductor device can be applied to various electronic devices that provide light by being disposed in its housing.

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

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

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

[0385] The lighting device can include a light source module that includes a substrate and the semiconductor device according to an embodiment. The lighting device can further include: a heat dissipation unit configured to dissipate the heat of the light source module; and a power supply unit configured to process or convert an electrical signal provided by an external source and provide the electrical signal to the light source module. Moreover, the lighting device can include a lamp, a headlight, or a streetlight.

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

[0387] The reflector 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 reflector to guide the light emitted by the light emitting module forward. The optical sheet can include a prism sheet, etc., 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 a 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-lit backlight unit.

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

[0390] Similar to a light-emitting device, the laser diode can include a first-conductive semiconductor layer, an active layer, and a second-conductive semiconductor layer having the above structure. The laser diode can also utilize the electroluminescence phenomenon, in which light is emitted when current flows after a p-type first-conductive semiconductor and an n-type second-conductive semiconductor are joined to each other, but there are differences in the direction and phase of the emitted light. That is, the laser diode utilizes stimulated emission and constructive interference so that light having a single specific wavelength can be emitted in the same direction with the same phase. Due to these characteristics, the laser diode can be used in optical communication devices, medical devices, semiconductor processing devices, 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 photocell (silicon or selenium), a light-output element (cadmium sulfide or cadmium selenide), a photodiode (PD having a peak wavelength in the visible-blind spectral region or the true-blind spectral region), a phototransistor, a photomultiplier tube, a phototube (vacuum or gas-filled), an infrared (IR) detector, etc., but the present invention is not limited thereto.

[0392] Generally, a direct-bandgap semiconductor with high photoelectric conversion efficiency can be used to manufacture semiconductor devices such as photodetectors. 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, and a metal-semiconductor-metal (MSM) photodetector, etc.

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

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

[0395] In addition, a solar cell can be used as a rectifier for an electronic circuit by utilizing the rectifying characteristics of a common diode of a p-n junction, and can be applied to an oscillation circuit of a microwave circuit or the like.

[0396] In addition, the above semiconductor device is not necessarily implemented only with semiconductors. Depending on the specific circumstances, the semiconductor device may also include a metal material. For example, a 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] Although the present invention has been described with reference to exemplary embodiments, these embodiments are merely examples and do not limit the present invention. Those skilled in the art should understand that various modifications and applications can be made without departing from the essential characteristics of the embodiments. For example, the elements described in detail in the above embodiments can be modified and implemented. In addition, the differences related to these modifications and applications should be understood to be included within the scope of the present invention defined by the appended claims.

Claims

1. A semiconductor device, comprising: a light-emitting structure, the light-emitting structure comprising: a first semiconductor layer; a second semiconductor layer; and an active layer containing aluminum and disposed between the first semiconductor layer and the second semiconductor layer; wherein when a primary ion bombards the light-emitting structure and sputters secondary ions containing aluminum from the first semiconductor layer, the active layer, and the second semiconductor layer, secondary ions containing aluminum with corresponding intensities are generated along the thickness directions of the first semiconductor layer, the active layer, and the second semiconductor layer; a first intensity position that exhibits a maximum intensity in the second semiconductor layer, and the intensity is a first intensity; a third intensity position that exhibits a minimum intensity in the entire region of the light-emitting structure, and the intensity is a third intensity; a fourth intensity position that exhibits a minimum intensity in the first semiconductor layer, and the intensity is a fourth intensity; a second intensity position that is located at a position separated from the first intensity and is a position of the maximum peak intensity in the region between the first intensity and the fourth intensity, and the intensity is a second intensity; wherein the first intensity position and the third intensity position are separated in a first direction, and the second intensity position and the first intensity position are separated in the first direction; wherein the second semiconductor layer includes a second region, and the second region includes a secondary ion intensity between the first intensity and the third intensity; wherein the light-emitting structure further includes a third region, and the third region includes a secondary ion intensity between the first intensity and the second intensity; the active layer is disposed within the third region; 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; wherein a first intensity difference between the second intensity and the fourth intensity is less than a second intensity difference between the first intensity and the third intensity.

2. The semiconductor device according to claim 1, wherein, The second semiconductor layer includes a P-type semiconductor layer and an electron blocking layer, and the first semiconductor layer is an N-type semiconductor layer.

3. The semiconductor device according to claim 2, wherein, The ratio of the first difference to the second difference ranges from 1:1.2 to 1:

10. The first difference is the difference between the average aluminum composition of the electron blocking layer and the aluminum composition at a first point. The second difference is the difference between the average aluminum composition of the electron blocking layer and the aluminum composition at a second point. The first point is the point where the aluminum composition of the second semiconductor layer is the same as the aluminum composition of the well layer closest to the second semiconductor layer in the active layer; and the second point is the point where the second semiconductor layer has the same dopant composition as the aluminum composition.

4. The semiconductor device according to claim 2, wherein, The P-type semiconductor layer includes at least a 2-1 conductive semiconductor layer and a 2-2 conductive semiconductor layer; the aluminum composition of the 2-1 conductive semiconductor layer is lower than that of the 2-2 conductive semiconductor layer, and both the 2-1 conductive semiconductor layer and the 2-2 conductive semiconductor layer are made of AlGaN.

5. The semiconductor device according to claim 2, wherein, The P-type semiconductor layer includes a semiconductor layer in which the aluminum composition decreases gradually with a slope as it moves away from the active layer.

6. The semiconductor device according to claim 1, wherein, The first semiconductor layer includes a first region, and the first region includes a secondary ion intensity between the second intensity and the fourth intensity.

7. The semiconductor device according to claim 2, wherein, The electron blocking layer has an aluminum composition of 50% to 90%.

8. The semiconductor device according to claim 1, wherein, The first semiconductor layer includes a first sub-layer of the first conductive semiconductor layer, a second sub-layer of the first conductive semiconductor layer, and a third sub-layer of the first conductive semiconductor layer. Among them, the second sub-layer of the first conductive semiconductor layer is disposed between the first sub-layer of the first conductive semiconductor layer and the third sub-layer of the first conductive semiconductor layer, and the fourth intensity position is located in the second sub-layer of the first conductive semiconductor layer.

9. The semiconductor device according to claim 8, wherein the Al content of the second sub-layer of the first conductive semiconductor layer is 30% to 70%.

10. The semiconductor device according to claim 1, wherein, The ratio of the second shortest distance to the first shortest distance of the second semiconductor layer is 1:1.25 to 1:

100. The second shortest distance is the distance from the first surface to the second point, and the first shortest distance is the distance from the first surface to the first point; The first surface is the surface of the second semiconductor layer away from the active layer; The first point is the point where the aluminum composition of the second semiconductor layer is the same as that of the well layer closest to the second semiconductor layer in the active layer; and The second point is the point where the second semiconductor layer has the same dopant composition as the aluminum composition.

11. The semiconductor device according to claim 10, wherein, The ratio of the second shortest distance to the first shortest distance is in the range of 1:1.25 to 1:

10.

12. 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 part and a 1-2 part. The first intensity position is located in the 1-1 part, and the thickness of the 1-1 part is 0.1 nm to 4 nm.

13. The semiconductor device according to claim 1 or 10, wherein, The first semiconductor layer includes a second intensity part at the second intensity position. The intensity of the second intensity part is the second intensity, and the thickness of the second intensity part is less than the sum of the thicknesses of a pair of well layers and barrier layers in the active layer.

14. The semiconductor device according to claim 1, wherein, The ratio of the first intensity difference between the second intensity position and the fourth intensity position to the second intensity difference between the first intensity position and the third intensity position is in the range of 1:1.5 to 1:2.

5.

15. A semiconductor device, comprising: A light-emitting structure, the light-emitting structure comprising: A first semiconductor layer; A second semiconductor layer; and An active layer containing aluminum and disposed between the first semiconductor layer and the second semiconductor layer; Wherein 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 with corresponding intensities are generated along the thickness directions of the first semiconductor layer, the active layer, and the second semiconductor layer; A first intensity position, which exhibits the maximum intensity in the second semiconductor layer, and its intensity is the first intensity; A second intensity position, located at a position separated from the first intensity, which exhibits the maximum intensity in the first semiconductor layer; Wherein, the second semiconductor layer includes a P-type semiconductor layer and an electron blocking layer, the electron blocking layer includes a 1-1 part and a 1-2 part, the first intensity position is located in the 1-1 part, and the thickness of the 1-1 part is 0.1 nm to 4 nm.

16. The semiconductor device according to claim 15, wherein, The first semiconductor layer includes a second intensity part located at the second intensity position, the intensity of the second intensity part is the second intensity, and the thickness of the second intensity part is less than the sum of the thicknesses of a pair of well layers and barrier layers in the active layer.

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