KR102594206B1 - Semiconductor device - Google Patents

Abstract

The embodiment discloses a semiconductor device that can improve low current yield and lower operating voltage by adjusting the thickness of the first conductivity type semiconductor layer.

Description

Semiconductor device {SEMICONDUCTOR DEVICE}

The embodiment relates to a semiconductor device.

Semiconductor devices containing compounds such as GaN and AlGaN have many advantages, such as having a wide and easily adjustable band gap energy, and can be used in a variety of ways, such as light emitting devices, light receiving devices, and various diodes.

In particular, light-emitting devices such as light emitting diodes and laser diodes using group 3-5 or group 2-6 compound semiconductor materials have been developed into red, green, and green colors through the development of thin film growth technology and device materials. Various colors such as blue and ultraviolet rays can be realized, and efficient white light can also be realized by using fluorescent materials or combining colors. Compared to existing light sources such as fluorescent lights and incandescent lights, it has low power consumption, semi-permanent lifespan, and fast response speed. , has the advantages of safety and environmental friendliness.

In addition, when light-receiving devices such as photodetectors or solar cells are manufactured using group 3-5 or group 2-6 compound semiconductor materials, the development of device materials absorbs light in various wavelength ranges to generate photocurrent. By doing so, light of various wavelengths, from gamma rays to radio wavelengths, can be used. In addition, it has the advantages of fast response speed, safety, environmental friendliness, and easy control of device materials, so it can be easily used in power control, ultra-high frequency circuits, or communication modules.

Therefore, semiconductor devices can replace the transmission module of optical communication means, the light emitting diode backlight that replaces the cold cathode fluorescence lamp (CCFL) that constitutes the backlight of LCD (Liquid Crystal Display) display devices, and fluorescent or incandescent light bulbs. Applications are expanding to include white light-emitting diode lighting devices, automobile headlights and traffic lights, and sensors that detect gas or fire. Additionally, the applications of semiconductor devices can be expanded to high-frequency application circuits, other power control devices, and communication modules.

In particular, light-emitting devices that emit light in the ultraviolet wavelength range have a curing or sterilizing effect and can be used for curing, medical purposes, and sterilization.

Recently, research on ultraviolet light-emitting devices has been active, but there is still a problem in that ultraviolet light-emitting devices are difficult to implement vertically, and when a GaN thin film is formed between the P semiconductor layer and the electrode for ohmic properties, the light output is reduced. There is.

An embodiment provides a semiconductor device with improved ohmic characteristics.

Additionally, a semiconductor device with improved light output is provided.

Additionally, a vertical ultraviolet light emitting device is provided.

The problem to be solved in the embodiment is not limited to this, and it will also include means of solving the problem described below and purposes and effects that can be understood from the embodiment.

A semiconductor device according to an embodiment includes a first conductivity type semiconductor layer containing Al; a second conductive semiconductor layer containing Al; and an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer and containing Al. It includes, and when primary ions collide with the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer, Al ions are generated from each of the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer. is released, at a first point where the Al ion intensity is the lowest, and arranged to be spaced apart from the first point in the first direction, and at a second point where the peak of the Al ion intensity is the highest, from the second point in the first direction. a third point in the spaced apart region having the lowest Al ion intensity, a fourth point having the strongest Al ion intensity peak between the second point and the third point, and spaced apart from the third point in the first direction. A fifth point in the region where the Al ion intensity is the greatest, and a sixth point disposed between the third point and the fifth point, which is greater than the Al ion strength of the third point and smaller than the Al ion strength of the fifth point. Includes, wherein the first direction is a direction from the second conductive semiconductor layer toward the active layer, and the difference in Al ion strength between the second point and the third point is the difference between the first point and the third point. greater than the difference in Al ion strength, the second conductive semiconductor layer includes a first region disposed between the first point and the second point, and the active layer includes a first region disposed between the second point and the fourth point. and a second region disposed, wherein the first conductive semiconductor layer includes a third region disposed between the fourth point and the fifth point, and the third region has an Al ion strength of the third point. and a 3-1 region having an Al ion intensity corresponding to that of the sixth point, and a 3-2 region having an Al ion strength corresponding to the Al ion strength of the sixth point, and a first direction of the 3-1 region. The ratio of the distance in the first direction of the 3-2 area is 1:2 to 1:4.

According to an embodiment, ohmic characteristics are improved and the operating voltage can be lowered.

Additionally, light output can be improved by suppressing light absorption within the semiconductor device.

The various and beneficial advantages and effects of the present invention are not limited to the above-described content, and may be more easily understood through description of specific embodiments of the present invention.

1 is a conceptual diagram of a semiconductor structure according to an embodiment of the present invention,
Figure 2 is a graph showing the aluminum (Al) composition of a semiconductor structure according to an embodiment of the present invention;
3 is Sims data of a semiconductor structure according to an embodiment of the present invention,
Figure 4 is an enlarged view of part A of Figure 3,
Figure 5 is an enlarged view of part B of Figure 3,
Figure 6 is a first modified example of Figure 3,
Figure 7 is a second modification of Figure 3,
Figure 8 is a diagram showing the first dopant ion concentration and the second dopant ion concentration;
9 is a conceptual diagram of a semiconductor device according to an embodiment of the present invention,
Figure 10 is an enlarged view of part A of Figure 9;
Figure 11 is an enlarged view of part B of Figure 9,
12 is a plan view of a semiconductor device according to an embodiment of the present invention;
Figure 13 is an enlarged view of part C of Figure 12,
14 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention;
16 is a plan view of a semiconductor device package according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

However, the technical idea of the present invention is not limited to some of the described embodiments, but may be implemented in various different forms, and as long as it is within the scope of the technical idea of the present invention, one or more of the components may be optionally used between the embodiments. It can be used by combining and replacing.

In addition, terms (including technical and scientific terms) used in the embodiments of the present invention, unless specifically defined and described, are generally understood by those skilled in the art to which the present invention pertains. It can be interpreted as meaning, and the meaning of commonly used terms, such as terms defined in a dictionary, can be interpreted by considering the contextual meaning of the related technology.

Additionally, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention.

In this specification, the singular may also include the plural unless specifically stated in the phrase, and when described as "at least one (or more than one) of A and B and C", it is combined with A, B, and C. It can contain one or more of all possible combinations.

Additionally, when describing the components of an embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used.

These terms are only used to distinguish the component from other components, and are not limited to the essence, sequence, or order of the component.

And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, the component is not only directly connected, coupled or connected to that other component, but also is connected to that component. It can also include cases where other components are 'connected', 'combined', or 'connected' due to another component between them.

Additionally, when described as being formed or disposed "above" or "below" each component, "above" or "below" refers not only to cases in which two components are in direct contact with each other; It also includes cases where one or more other components are formed or disposed between two components. In addition, when expressed as "top (above) or bottom (bottom)", it may include not only the upward direction but also the downward direction based on one component.

FIG. 1 is a conceptual diagram of a semiconductor structure according to a first embodiment of the present invention, and FIG. 2 is a graph showing the aluminum composition of a semiconductor structure according to a first embodiment of the present invention.

Referring to Figures 1 and 2, the semiconductor device according to the embodiment includes a buffer layer 121, a first conductivity type semiconductor layer 124, a second conductivity type semiconductor layer 127, and a first conductivity type semiconductor layer 124. ) and a semiconductor structure 120 including an active layer 126 disposed between the second conductive semiconductor layer 127.

The light emitting structure according to an embodiment of the present invention can output light in the ultraviolet wavelength range. For example, the light-emitting structure may output light in the near-ultraviolet wavelength range (UV-A), light in the far-ultraviolet wavelength range (UV-B), or light in the deep ultraviolet wavelength range (UV-C). Can be printed. The wavelength range can be determined by the Al composition ratio of the light emitting structure. In addition, the light emitting structure can output light of various wavelengths with different light intensities, and the peak wavelength of the light with the strongest intensity relative to the intensity of other wavelengths among the wavelengths of light emitted is near ultraviolet rays, far ultraviolet rays, or deep ultraviolet rays. It could be ultraviolet rays.

For example, light in the near-ultraviolet wavelength range (UV-A) may have a main peak in the range of 320 nm to 420 nm, and light in the far-ultraviolet wavelength range (UV-B) may have a main peak in the range of 280 nm to 320 nm, Light in the deep ultraviolet wavelength range (UV-C) may have a main peak in the range of 100 nm to 280 nm. The light emitting structure can produce ultraviolet light with a maximum peak wavelength in the wavelength range of 100 nm to 420 nm.

The first conductive semiconductor layer 124 may be implemented as a compound semiconductor such as group III-V or group II-VI, and may be doped with a first dopant. _{The first} conductive semiconductor layer 124 is a semiconductor material with _a composition formula of _In For example, it may be selected from AlGaN, AlN, InAlGaN, etc. And, the first dopant may be an n-type dopant such as Si, Ge, Sn, Se, or 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.

The first conductive semiconductor layer 124 may include a first sub-semiconductor layer 124a, a second sub-semiconductor layer 124b, a third sub-semiconductor layer 124c, and a fourth sub-semiconductor layer 124d. there is.

The fourth sub-semiconductor layer 124d may be disposed closest to the active layer 126. The aluminum composition of the fourth sub-semiconductor layer 124d may be the same as or lower than that of the first sub-semiconductor layer 124a.

When the semiconductor structure 120 emits light (UV-C) in the deep ultraviolet wavelength range, the aluminum composition of the fourth sub-semiconductor layer 124d is 40% to 70%, and the aluminum composition of the first sub-semiconductor layer 124a is 40% to 70%. The composition may be 50% to 80%.

When the aluminum composition of the fourth sub-semiconductor layer 124d is 40% or more, light extraction efficiency can be improved by lowering the absorption rate of light (UV-C) in the deep ultraviolet wavelength range emitted from the active layer 126. Additionally, when the aluminum composition of the fourth sub-semiconductor layer 124d is 70% or less, current injection characteristics into the active layer 126 and current diffusion characteristics within the fourth sub-semiconductor layer 124d can be secured.

In addition, when the aluminum composition of the first sub-semiconductor layer 124a is 50% or more, the light extraction efficiency can be improved by lowering the absorption rate of light (UV-C) in the deep ultraviolet wavelength range emitted from the active layer 126, and the light extraction efficiency can be improved by 80%. When the ratio is below, the current injection characteristics into the active layer 126 and the current diffusion characteristics within the first sub-semiconductor layer 124a can be secured.

Additionally, the aluminum composition of the first sub-semiconductor layer 124a may be higher than that of the fourth sub-semiconductor layer 124d. In this case, it may be more advantageous for light to be extracted from the active layer 126 to the outside of the semiconductor structure 120 due to the difference in refractive index, and thus the light extraction efficiency of the semiconductor structure 120 may be improved.

The thickness of the fourth sub-semiconductor layer 124d may be thinner than the thickness of the first sub-semiconductor layer 124a. The first sub-semiconductor layer 124a may be 130% or more of the thickness of the fourth sub-semiconductor layer 124d. According to this configuration, the third sub-semiconductor layer 124c is disposed after sufficiently securing the thickness of the first sub-semiconductor layer 124a, which has a high aluminum composition, and thus the crystallinity of the entire semiconductor structure 120 can be improved.

The aluminum composition of the third sub-semiconductor layer 124c may be lower than that of the first conductivity-type semiconductor layer 124 and the second conductivity-type semiconductor layer 127. The third sub-semiconductor layer 124c can prevent the active layer 126 from being damaged by absorbing the laser irradiated to the semiconductor structure 120 during a laser lift-off (LLO) process. Accordingly, the optical and electrical properties of the semiconductor device can be improved.

The thickness and aluminum composition of the third sub-semiconductor layer 124c can be appropriately adjusted to absorb the laser irradiated to the semiconductor structure 120 during the LLO process. Therefore, the aluminum composition of the third sub-semiconductor layer 124c can correspond to the laser wavelength used during the LLO process. When the peak wavelength of the LLO laser is 200 nm to 300 nm, the aluminum composition of the third sub-semiconductor layer 124c is 30 nm. % to 60%.

A control layer 124e may be disposed between the fourth sub-semiconductor layer 124d and the active layer 126. The control layer 124e lowers the energy of the first carriers injected from the first conductive semiconductor layer 124 toward the active layer 126, thereby reducing the concentration or density of the first and second carriers recombined in the active layer 126. You can strike a balance. Therefore, the light output characteristics of the semiconductor device can be improved by improving the luminous efficiency. The aluminum composition of the control layer 124e may be higher than that of the first conductivity type semiconductor layer 124, the active layer 126, and the second conductivity type semiconductor layer 127. For example, the control layer 124e may be an n ⁺ AlGaN layer.

The active layer 126 may be disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127. The active layer 126 is a layer where electrons (or holes) injected through the first conductive semiconductor layer 124 and holes (or electrons) injected through the second conductive semiconductor layer 127 meet. The active layer 126 transitions to a low energy level as electrons and holes recombine, and can generate light having an ultraviolet wavelength.

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, or a quantum wire structure.

The active layer 126 may include a plurality of well layers 126a and a barrier layer 126b. The well layer 126a and the barrier layer 126b may have a composition formula of In _x2 Al _y2 Ga _{1 -x2- y2} N (0≤x2≤1, 0<y2≤1, 0≤x2+y2≤1) . The aluminum composition of the well layer 126a may vary depending on the wavelength at which it emits light.

The second conductive semiconductor layer 127 is disposed on the active layer 126 and may be implemented with a compound semiconductor such as group III-V or group II-VI. The second conductive semiconductor layer 127 has a second Dopants may be doped.

The second conductive semiconductor layer 127 is a semiconductor material with a composition formula of In _x5 Al _y2 Ga _{1 -x5- y2} N (0≤x5≤1, 0<y2≤1, 0≤x5+y2≤1) or AlGaN. , AlInN, AlN, AlGaAs, and AlGaInP may be formed of a selected material.

When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, Ba, etc., the second conductive semiconductor layer 127 doped with the second dopant may be a p-type semiconductor layer.

The blocking layer 129 may be disposed between the active layer 126 and the second conductivity type semiconductor layer 127. The blocking layer 129 blocks the flow of carriers supplied from the first conductive semiconductor layer 124 to the second conductive semiconductor layer 127, thereby increasing the probability of electrons and holes recombining within the active layer 126. can increase.

The energy band gap of the blocking layer 129 may be larger than that of the active layer 126 and the second conductive semiconductor layer 127. Since the blocking layer 129 is doped with the second dopant, it may be defined as a partial area of the second conductivity type semiconductor layer 127. That is, the second conductive semiconductor layer 127 may be defined as including a P-type semiconductor layer and a blocking layer 129.

The blocking layer 129 is made of a semiconductor material with a composition formula of In _x1 Al _y1 Ga _{1 -x1- y1} N (0≤x1≤1, 0≤y1≤1, 0≤x1+y1≤1), for example, AlGaN, It may be selected from AlN, InAlGaN, etc., but is not limited thereto.

According to an embodiment, the first conductivity type semiconductor layer 124, the active layer 126, the blocking layer 129, and the second conductivity type semiconductor layer 127 may all include aluminum. Accordingly, the first conductivity type semiconductor layer 124, the active layer 126, the blocking layer 129, and the second conductivity type semiconductor layer 127 may have AlGaN, InAlGaN, or AlN compositions.

The blocking layer 129 may have an aluminum composition of 50% to 100%. If the aluminum composition of the blocking layer 129 is 50% or more, it may have a sufficient energy barrier to block the movement of carriers and may not absorb light emitted from the active layer 126.

The blocking layer 129 may include a first blocking layer 129a and a second blocking layer 129b. The aluminum composition of the first blocking layer 129a may increase in the direction from the first conductivity type semiconductor layer 124 to the second conductivity type semiconductor layer 127.

The aluminum composition of the first blocking layer 129a may be 80% to 100%. Accordingly, the first blocking layer 129a may be a portion with the highest Al composition within the semiconductor structure 120. The first blocking layer 129a may be AlGaN or AlN. Alternatively, the first blocking layer 129a may be a superlattice layer in which AlGaN and AlN are alternately arranged.

The thickness of the first blocking layer 129a may be about 0.1 nm to 4 nm. In order to effectively block the movement of carriers (eg, electrons), the first blocking layer 129a may be disposed to have a thickness of 0.1 nm or more. Additionally, in order to secure injection efficiency of carriers (e.g., holes) from the second conductive semiconductor layer 127 to the active layer 126, the thickness of the first blocking layer 129a may be 4 nm or less.

The third blocking layer 129c disposed between the first blocking layer 129a and the second blocking layer 129b may include a section that does not contain a dopant. Accordingly, the third blocking layer 129c may serve to prevent the dopant from diffusing from the second conductive semiconductor layer 127 to the active layer 126.

The second conductive semiconductor layer 127 may include a fifth sub-semiconductor layer 127a, a sixth sub-semiconductor layer 127b, and a seventh sub-semiconductor layer 127c.

The fifth sub-semiconductor layer 127a has a relatively uniform aluminum composition and can improve hole injection efficiency or crystallinity of the semiconductor structure 120. The thickness of the fifth sub-semiconductor layer 127a may be 20 nm to 60 nm. The aluminum composition of the fifth sub-semiconductor layer 127a may be 40% to 80%.

The thickness of the sixth sub-semiconductor layer 127b may be greater than 10 nm and less than 50 nm. For example, the thickness of the sixth sub-semiconductor layer 127b may be 25 nm. If the thickness of the sixth sub-semiconductor layer 127b is thicker than 10 nm, resistance in the horizontal direction may be reduced and current diffusion efficiency may be improved. In addition, when the thickness of the sixth sub-semiconductor layer 127b is less than 50 nm, the path through which light incident from the active layer 126 to the sixth sub-semiconductor layer 127b is absorbed may be shortened, and light extraction of the semiconductor device may be shortened. Efficiency can be improved.

The aluminum composition of the sixth sub-semiconductor layer 127b may be higher than that of the well layer 126a. The aluminum composition of the well layer 126a for generating deep ultraviolet or far ultraviolet light may be about 20% to 60%. Accordingly, the aluminum composition of the sixth sub-semiconductor layer 127b may be greater than 40% and less than 80%. For example, if the aluminum composition of the well layer 126a is 30%, the aluminum composition of the sixth sub-semiconductor layer 127b may be 40%.

If the average aluminum composition of the sixth sub-semiconductor layer 127b is lower than the aluminum composition of the well layer 126a, the light extraction efficiency may decrease because the sixth sub-semiconductor layer 127b has a high probability of absorbing ultraviolet light. there is.

The seventh sub-semiconductor layer 127c may be a surface layer of the semiconductor structure 120 that is in contact with the second electrode. Current may be injected into the seventh sub-semiconductor layer 127c through the second electrode, and current injection efficiency may be controlled by the resistance between the seventh sub-semiconductor layer 127c and the second electrode. The resistance between the seventh sub-semiconductor layer 127c and the second electrode may be due to at least one of ohmic contact, Schottky contact, or tunnel effect, but is not necessarily limited thereto.

The seventh sub-semiconductor layer 127c may be implemented with a compound semiconductor such as group III-V or group II-VI, and may be doped with a first dopant. The seventh sub-semiconductor layer 127c is a semiconductor material with a composition formula of In _x1 Al _y1 Ga _{1 -x1-y1} N (0≤x1≤1, 0<y1≤1, 0≤x1+y1≤1), for example For example, it can be selected from AlGaN, InAlGaN, AlN, etc. And, the first dopant may be an n-type dopant such as Si, Ge, Sn, Se, or Te. That is, the seventh sub-semiconductor layer 127c may be the same n-type semiconductor layer as the first conductivity type semiconductor layer 124.

However, the seventh sub-semiconductor layer 127c may include both the first dopant and the second dopant. While the first dopant may be intentionally doped, the second dopant may be a diffusion of the second dopant doped into the second conductivity type semiconductor layer 127. However, it is not necessarily limited to this, and the seventh sub-semiconductor layer 127c may be intentionally doped with the first and second dopants to activate carriers.

Even if only the first dopant is doped into the seventh sub-semiconductor layer 127c, the doping concentration of the second dopant may be higher than that of the first dopant due to a memory effect.

At this time, the concentration ratio of the first dopant and the second dopant doped in the seventh sub-semiconductor layer 127c may be 0.01:1.0 to 0.8:1.0. When the concentration ratio is 0.01:1.0 to 0.8:1.0, ohmic resistance may be lowered due to the tunnel effect.

For example, the first dopant concentration of the seventh sub-semiconductor layer 127c may be 1×10 ¹⁸ cm ^-3 to 2×10 ²⁰ cm ^-3 . Additionally, the concentration of the second dopant of the seventh sub-semiconductor layer 127c may be 1×10 ¹⁹ cm ^-3 to 2×10 ²¹ cm ^-3 .

At this time, the first dopant concentration of the seventh sub-semiconductor layer 127c may be equal to or higher than the first dopant concentration of the first conductive semiconductor layer 124 and the first dopant concentration of the barrier layer 126b.

The thickness of the seventh sub-semiconductor layer 127c may be 1 nm to 10 nm. If the thickness of the seventh sub-semiconductor layer 127c is thicker than 10 nm, there is a problem in which carrier injection efficiency is reduced. Accordingly, the thickness of the seventh sub-semiconductor layer 127c may be smaller than that of the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127.

The aluminum composition of the seventh sub-semiconductor layer 127c may be 20% to 70%. When the aluminum composition is 20% or more, the difference in aluminum composition with the ultraviolet ray-emitting well layer 126a is reduced, thereby improving light absorption. Additionally, when the aluminum composition is 70% or less, the operating voltage is lowered, so light output can be improved.

The aluminum composition of the seventh sub-semiconductor layer 127c may decrease as it approaches the surface. The reduction width of the sixth sub-semiconductor layer 127b may be different from or the same as that of the seventh sub-semiconductor layer 127c.

According to an embodiment, the aluminum composition (Q3) of the seventh sub-semiconductor layer 127c may be lower than the aluminum composition (Q10) of the well layer 126a and the aluminum composition (Q4) of the third sub-semiconductor layer 124c. . In this case, the resistance with the second electrode can be effectively lowered.

However, it is not necessarily limited to this, and since the hole injection efficiency of the seventh sub-semiconductor layer 127c is improved by the tunnel effect, the aluminum composition may be controlled to be the same as that of the well layer 126a or to be higher than that of the well layer 126a. .

FIG. 3 is sims data of a semiconductor structure according to an embodiment of the present invention, FIG. 4 is an enlarged view of portion A of FIG. 3, FIG. 5 is an enlarged view of portion B of FIG. 3, and FIG. 6 is the first portion of FIG. 3. This is a modified example, Figure 7 is a second modified example of Figure 3, and Figure 8 is a diagram showing the first dopant ion concentration and the second dopant ion concentration.

Referring to Figures 3 and 4, the semiconductor structure 120 contains aluminum (Al), gallium (Ga), a first dopant, The spectrum of the second dopant may change. The first dopant may be silicon (Si) and the second dopant may be magnesium (Mg), but are not necessarily limited thereto.

SIMS data may be analysis data by Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS).

SIMS data can be analyzed by irradiating primary ions to the surface of a target and counting the number of secondary ions released. At this time, the primary ion may be selected from O ₂ ⁺ , Cs ⁺ Bi ^{+ ,} etc., the acceleration voltage may be adjusted within 20 to 30 keV, the irradiation current may be adjusted within 0.1 pA to 5.0 pA, and the irradiation area may be 20nm×20nm.

SIMS data can collect secondary ion mass spectra while gradually etching from the surface (E0, point where depth is 0) of the second conductive semiconductor layer 127 toward the first conductive semiconductor layer 124. there is. Secondary ions may be constituent elements of the semiconductor layer. By way of example, the secondary ion may be aluminum, gallium, a first dopant, and a second dopant, but is not necessarily limited thereto.

The results of Sims analysis can be interpreted as a spectrum for the intensity of secondary ions or the doping concentration of secondary ions. In the interpretation of secondary ion intensity or doping concentration, it is within 5%, that is, 0.95 times the corresponding doping concentration. It may contain noise with a size of 1.05 times. Accordingly, the description “equal to/corresponds to” may mean including noise of 0.95 times or more to 1.05 times or less of a specific secondary ion strength or doping concentration.

For example, if there is a peak adjacent to the first point but has a size 0.95 to 1.05 times the size of the first point, the surrounding peak may be understood to have the same intensity as the aluminum intensity of the first point.

Ion strength according to embodiments may increase or decrease depending on measurement conditions. However, as the intensity of the primary ion increases, the intensity graph of the secondary ion (aluminum ion) may also overall increase, and as the intensity of the primary ion decreases, the intensity graph of the secondary ion (aluminum ion) may also overall decrease. Therefore, the change in ionic strength in the thickness direction may be similar even if the measurement conditions are changed.

When irradiated with primary ions, the first conductive semiconductor layer 124, the active layer 126, and the second conductive semiconductor layer 127 may each emit aluminum ions. Accordingly, the aluminum ion spectrum emitted from the first conductivity type semiconductor layer 124, the active layer 126, and the second conductivity type semiconductor layer 127 may be continuous.

The aluminum ion intensity may include a first point (P1) to a sixth point (P6) depending on the intensity level.

Referring to FIGS. 3 and 4 , the first point P1 may be a point in the semiconductor structure 120 where the aluminum ion intensity is lowest. The first point P1 may be the surface of the semiconductor structure 120. According to an embodiment, the surface of the second conductive semiconductor layer 127 may include aluminum to reduce absorption of light emitted from the active layer 126. Additionally, the second electrode may directly contact the surface of the second conductive semiconductor layer 127 to form ohmic.

The second point (P2) may be arranged to be spaced apart from the first point (P1) in the first direction (D2) and may be a point where the peak of the aluminum ion intensity is the highest. The first direction D2 may be a direction from the second conductivity type semiconductor layer 127 to the first conductivity type semiconductor layer 124. Here, the peak can be defined as a point having a local maximum point.

The ionic strength at the second point P2 may be the highest within the second conductive semiconductor layer 127. Accordingly, non-luminescent recombination of the first carrier with the second carrier in the second conductive semiconductor layer 127 can be prevented. Therefore, the light output of the semiconductor device can be improved. The ionic strength of the second point P2 may be the ionic strength of the first blocking layer 129a, but is not necessarily limited thereto.

The third point P5 may have the lowest aluminum ion intensity in a region spaced apart from the second point P2 in the first direction. Although the ionic strength of the third point P5 is greater than that of the first point P1, the ionic strength may be the lowest within the first conductivity type semiconductor layer 124.

The ionic strength of the third point P5 may be the ionic strength of the third sub-semiconductor layer 124c. Since the ionic strength of the third point P5 is sufficiently low, the resistance with the first electrode is lowered, thereby improving the injection efficiency of the current injected into the semiconductor structure 120. For this reason, the ionic strength at the third point P5 may be placed at the lowest in the first direction from the second point P2.

The fourth point P3 may have the strongest aluminum ion intensity peak between the second point P2 and the third point P5. Here, the peak can be defined as a point having a local maximum point. The ionic strength at the fourth point P3 may be the highest in the first conductive semiconductor layer 124, but is not necessarily limited thereto.

The ionic strength of the fourth point P3 may be the ionic strength of the control layer 124e. Since the aluminum ion strength of the control layer 124e is high, the first carrier energy injected from the first conductive semiconductor layer 124 toward the active layer 126 decreases, and the first and second carriers recombine in the active layer 126. The concentration or density can be balanced. Therefore, the light output characteristics of the semiconductor device can be improved by improving the light emission efficiency.

The fifth point P7 may have the highest aluminum ion intensity in a region spaced apart from the third point P5 in the first direction. The ionic strength of the fifth point P7 may be the ionic strength of the first sub-semiconductor layer 124a. The area corresponding to the thickness of the first sub-semiconductor layer 124a may be relatively uniform.

The ionic strength of the sixth point (P6) may be greater than the ionic strength of the third point (P5) and less than the Al ion strength of the fifth point (P7). The ionic strength of the sixth point P6 may be the ionic strength of the second sub-semiconductor layer 124b. The area corresponding to the thickness of the second sub-semiconductor layer 124b may have relatively uniform intensity.

According to an embodiment, the crystallinity of the semiconductor structure 120 may be improved by sequentially lowering the ionic strength at the sixth point P6. If the ionic strength suddenly decreases from the ionic strength at the fifth point P7 to the ionic strength at the third point P5, the crystallinity of the semiconductor structure 120 may deteriorate.

According to the embodiment, since the surface of the second conductive semiconductor layer 127 has an AlGaN composition, the aluminum ion intensity at the first point P1 is high. In addition, the aluminum ion strength at the third point P5 is relatively small in order to lower the resistance with the first electrode. Accordingly, the difference in aluminum ion intensity between the second point (P2) and the third point (P5) may be greater than the difference in aluminum ion intensity between the first point (P1) and the third point (P5). However, it is not necessarily limited to this.

The second conductive semiconductor layer 127 includes a first region disposed between the first point (P1) and the second point (P2), and the active layer 126 includes the second point (P2) and the fourth point (P2). P3), and the first conductive semiconductor layer 124 may include a third region disposed between the fourth point P3 and the fifth point P7. The first region may include Mg, and the third region may include Si.

The active layer 126 may include a plurality of peaks P61 and valleys P62. The ionic intensity of the peak (P61) may be greater than the ionic intensity of the valley (P62). The peak P61 may be the ionic intensity of the barrier layer 126b, and the valley P62 may be the ionic intensity of the well layer 126a. Among the wavelengths of light emitted from the plurality of valleys P62, the wavelength of light with the greatest intensity may be 100 nm to 320 nm.

The third region is a 3-1 region (L1) having an intensity corresponding to the aluminum ion intensity at the third point (P5), and a 3-2 region (L1) having an intensity corresponding to the aluminum ion intensity at the sixth point (P6). It may include a region (L2).

The first aluminum strength difference D1 between the second point P2 and the fifth point P5 may be smaller than the second aluminum strength difference D2 between the second point P2 and the first point P1. In this case, the aluminum strength at the first point P1 is low, so the contact resistance with the second electrode can be lowered. However, if the aluminum intensity at the first point (P1) increases, the second aluminum intensity difference (D2) may decrease. Accordingly, the first aluminum intensity difference (D1) may be greater than the second aluminum intensity difference (D2). Alternatively, the first aluminum intensity difference (D1) may be the same as the second aluminum intensity difference (D2).

For example, the ratio (D1:D2) between the first aluminum intensity difference (D1) and the second aluminum intensity difference (D2) may be 1:0.2 to 1:2. When the intensity difference is 1:0.2 or more, the second aluminum intensity difference (D2) can be sufficiently secured, and thus the contact resistance between the second conductive semiconductor layer and the second electrode can be improved. When the intensity difference is 1:2 or less, the second aluminum intensity difference D2 can be prevented from becoming relatively large, and the aluminum intensity change rate with respect to the thickness of the 2-1 conductive type semiconductor layer 127a can be adjusted so that it does not become too large. Accordingly, the crystallinity of the semiconductor structure can be improved, and the optical properties of the semiconductor device can be improved by improving the transmittance of the 2-1 conductivity type semiconductor layer 127a with respect to light emitted from the active layer 126.

Referring to FIG. 5, the 3-1 area L1 can be defined as an area having an intensity corresponding to the intensity of the third point P5. The 3-1st region L1 may have an intensity ranging from 95% to 105% of the intensity of the third point P5. That is, both the strongest intensity (P52) and the weakest intensity (51) within the 3-1 area (L1) may be within the noise range.

The 3-2 area L2 can be defined as an area having an intensity corresponding to the intensity of the sixth point P6. The 3-2 region L2 may have an intensity ranging from 95% to 105% of the intensity of the sixth point P6.

For example, the distance in the first direction of the 3-1 region L1 may be 300 nm to 500 nm, and the distance in the first direction of the 3-2 region L2 may be 1000 nm to 1400 nm, but are not necessarily limited thereto.

The ratio of the distance in the first direction of the 3-1 area L1 and the distance in the first direction of the 3-2 area L2 may be 1:2 to 1:4. When the distance ratio is greater than 1:2, the thickness of the first conductive semiconductor layer 124 increases, thereby solving the problem of the light emitting structure being torn off during LLO. Additionally, it is possible to secure a sufficient thickness of the first conductivity type semiconductor layer to form irregularities. Irregularities may be formed on the surface of the first conductivity type semiconductor layer (124a-1 in FIG. 3). That is, since the thickness of the 3-2 region L2 is sufficiently secured, the current dispersion efficiency is not reduced even if irregularities are formed on the surface of the first conductive semiconductor layer 124, and the low current yield is improved, and the driving voltage is lowered. It can be lowered.

Irregularities may be formed on the surface 124a-1 of the first conductivity type semiconductor layer by wet etching the light emitting structure using an etching solution. Therefore, defects in the light emitting structure (for example, threading dislocation, etc.) may cause the etching solution to penetrate into the light emitting structure, which may reduce the reliability of the semiconductor device. Additionally, when the etching solution penetrates into the 3-1 region L1, the bonding area between the first electrode and the 3-1 region L1 may be damaged, thereby reducing the reliability of the semiconductor device.

Therefore, the reliability of the semiconductor device can be improved by arranging the ratio of the distance in the first direction of the 3-1 region (L1) to the distance in the first direction of the 3-2 region (L2) at the above-mentioned 1:2 or more. there is. Additionally, when using a process for growing a light emitting structure on a growth substrate, the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer may be grown in that order. Therefore, most defects in the light emitting structure can be suppressed in the first conductivity type semiconductor layer. At this time, if the first conductivity type semiconductor layer becomes too thick, defects may extend to the active layer and the second conductivity type semiconductor layer due to stress, etc. And if the number of such extended defects increases, the reliability of the semiconductor device may decrease. Additionally, if light emitted from the active layer is absorbed due to a defect or light is absorbed in the 3-2 region L2, the light extraction efficiency of the semiconductor device may be reduced. Therefore, the reliability of the semiconductor device can be improved by arranging the ratio of the distance in the first direction of the 3-1 region L1 to the distance in the first direction of the 3-2 region L2 at 1:4 or less. Light extraction efficiency can also be improved.

When the distance ratio is less than 1:4, the thickness of the first conductivity type semiconductor layer 124 decreases, so the luminance can be improved. In the case of an ultraviolet light emitting device, light is emitted in TM mode, so if the first conductive semiconductor layer 124 becomes too thick, there is a problem that the luminous intensity decreases.

Example 1 of Table 1 below was tested by increasing the thickness of the existing first conductive semiconductor layer by 0.7 μm, and Example 2 was tested by increasing the thickness of the existing first conductive semiconductor layer by 1.1 μm.

Leakage current yield Driving voltage (V) Po(mW) Ref 100% 100% 100% Example 1 144% 95% 98.3% Example 2 167% 92% 95%

Referring to Table 1, it can be seen that as the thickness of the first conductive semiconductor layer 124 increases, the low current yield improves and the driving voltage decreases. However, it can be seen that as the thickness of the first conductive semiconductor layer 124 increases, the luminous intensity decreases. Therefore, as described above, when the ratio of the thickness of the 3-1 region (L1) and the thickness of the 3-2 region (L2) is controlled to 1:2 to 1:4, the decrease in luminous intensity is minimized and low current yield is achieved. can be improved and the driving voltage can be lowered. The aluminum ion intensity at the third point (P5) may be greater than the aluminum ion intensity at the fifth point (P7). When the aluminum ion intensity at the third point P5 is high, the first carrier energy injected from the first conductive semiconductor layer 124 toward the active layer 126 decreases, and the first and second carriers recombine in the active layer 126. The concentration or density can be balanced. Therefore, the light output characteristics of the semiconductor device can be improved by improving the light emission efficiency.

However, it is not necessarily limited to this, and as shown in FIG. 6, the aluminum ion intensity at the fifth point P7 may be greater than the aluminum ion intensity at the third point P5. In this case, the aluminum composition of the first conductive semiconductor layer 124 may be increased, thereby improving crystallinity. Additionally, as shown in FIG. 7, the aluminum ion intensity at the third point P5 may be the same as the aluminum ion intensity at the fifth point P7.

Referring to FIG. 8, the doping concentration of the first dopant (eg, Si) may have a first doping concentration (S1) in the first conductivity type semiconductor layer 124. At this time, the first conductive semiconductor layer 124 may have a doping concentration (S2) lower than the first doping concentration (S1) in some regions. However, it is not necessarily limited to this, and the doping concentration of the first conductive semiconductor layer 124 may be uniform throughout the entire area.

The second doping concentration S4 may be the doping concentration of the barrier layer 126b of the active layer 126 and/or the fourth sub-semiconductor layer 124d. Accordingly, the injection efficiency of the first carrier injected into the active layer 126 can be improved, and the efficiency of luminescent recombination of the first carrier and the second carrier in the active layer 126 can be improved. Additionally, the operating voltage (Vf) can be lowered. The second doping concentration (S4) may have a plurality of peaks and valleys.

The third doping concentration S6 may be the doping concentration on the surface E0 of the semiconductor structure 120. The third doping concentration (S6) may be higher than the first doping concentration (S1) and the second doping concentration (S4). Accordingly, it can be confirmed that the surface layer of the semiconductor structure 120 according to the embodiment where the second electrode is disposed includes aluminum and the first dopant.

The fourth doping concentration S3 may be disposed between the first conductive semiconductor layer 124 and the active layer 126. The semiconductor layer having the fourth doping concentration (S3) has a relatively high resistance and can serve to disperse current.

The fifth doping concentration S5 may be disposed between the active layer 126 and the second conductivity type semiconductor layer 127. The fifth doping concentration S5 may be formed in the process of suppressing the first dopant for doping of the second dopant. The fourth doping concentration (S3) and the fifth doping concentration (S5) may be smaller than the first to third doping concentrations (S1, S4, and S6).

Referring to FIG. 5, the doping concentration of the second dopant (eg, Mg) is highest at the surface E0 and may gradually decrease as the distance from the surface increases. It can be seen that the doping concentration (M1) of the second dopant (eg, Mg) on the surface (E0) of the semiconductor structure 120 is higher than the doping concentration (S6) of the first dopant (eg, Si). This may be because the doping concentration of the second dopant increases due to the memory effect even though the surface of the semiconductor structure 120 is not doped with the second dopant.

The second dopant has a doping concentration that increases as it gets closer to the surface, but may include a certain section (a section between M2 and M3) in which the doping concentration decreases as it gets closer to the surface. According to this reversal section, the concentration of the second dopant is reduced and the resistance is increased, thereby improving the hole dispersion efficiency.

The second dopant may be present in all areas of the second conductive semiconductor layer 127 and some areas of the active layer 126, but is not necessarily limited thereto. The second dopant can be placed only within the second conductive semiconductor layer 127, but can diffuse into the active layer 126. Accordingly, the injection efficiency of the second dopant injected into the active layer 126 can be improved. However, when the second dopant diffuses to the first conductivity type semiconductor layer 124, leakage current of the semiconductor device and/or non-luminous recombination of the first and second carriers occur, reducing the reliability and/or luminous efficiency of the semiconductor device. It can be.

FIG. 9 is a conceptual diagram of a semiconductor device according to the first embodiment, FIG. 10 is an enlarged view of portion A of FIG. 9, and FIG. 11 is an enlarged view of portion B of FIG. 9.

9 and 10, the semiconductor device 10 according to the embodiment includes a conductive substrate 170, a first conductivity type semiconductor layer 124, a second conductivity type semiconductor layer 127, and an active layer 126. A light emitting structure 120 including, a first electrode 142 electrically connected to the first conductive semiconductor layer 124, and a second electrode 146 electrically connected to the second conductive semiconductor layer 127. may include.

The light emitting structure 120 includes a second recess 128 that penetrates the second conductive semiconductor layer 127 and the active layer 126 and is disposed up to a partial area of the first conductive semiconductor layer 124 and a plurality of first It may include a recess (129).

The second recess 128 may extend continuously along the side of the light emitting structure 120. The second recess 128 may be a single recess that extends along the outer surface of the light emitting structure 120 to form a closed loop, but is not necessarily limited thereto and may be divided into a plurality of recesses.

By the second recess 128, the active layer 126 is divided into an inactive area OA1 disposed outside the second recess 128 and an active area IA1 disposed inside the second recess 128. can be separated.

A plurality of first recesses 129 may be disposed inside the second recess 128. The first recess 129 may have a first electrode 142 disposed therein and may serve as a path for injecting current into the first conductive semiconductor layer 124.

The inactive area OA1 may be a non-emission area where electrons and holes do not combine, and the active area IA1 may be an area where current is distributed and emit light.

The area of the active area IA1 disposed inside the second recess 128 may be larger than the area of the inactive area OA1 disposed outside the second recess 128 .

The ratio of the maximum area of the light emitting structure 120 and the maximum area of the plurality of first recesses 129 is

The ratio of the maximum area of the light emitting structure 120 and the maximum area of the second recess 128 may be 1:0.01 to 1:0.03. If the ratio between the maximum area of the light emitting structure 120 and the maximum area of the second recess 128 is less than 1:0.01, it may be difficult to prevent oxidation of the active layer 126 from contaminants. Additionally, if the ratio between the maximum area of the light emitting structure 120 and the maximum area of the second recess 128 is greater than 1:0.03, light efficiency may be reduced.

The passivation layer 180 surrounding the side and top surfaces of the light emitting structure 120 is connected to the light emitting structure 120 due to heat generation due to the operation of the semiconductor device, external high temperature and high humidity, and a difference in thermal expansion coefficient between the light emitting structure 120 and the like. Delamination may occur. Alternatively, cracks, etc. may occur in the passivation layer 180.

When peeling, cracks, etc. occur in the passivation layer 180, the light emitting structure 120 may be oxidized by external moisture or contaminants penetrating into the light emitting structure 120 from the outside.

In the case of ultraviolet light-emitting devices, the Al composition of the active layer 126 is relatively high, so it may be more vulnerable to oxidation. Accordingly, when the sidewall of the light emitting structure 120 is exposed due to a crack or the like, the active layer 126 may be rapidly oxidized and the light output may decrease.

According to an embodiment, the second recess 128 may be disposed between the inactive area OA1 and the active area IA1 to serve as a barrier. Additionally, the separation distance between the inactive area OA1 and the active area IA1 may be increased by the second recess 128 . Accordingly, even if the inactive area OA1 of the active layer 126 is oxidized, the active area IA1 of the active layer 126 can be prevented from being oxidized by the second recess 128 .

Referring to FIG. 10, the first insulating layer 131 is disposed below the light emitting structure 120 to electrically insulate the first electrode 142 from the active layer 126 and the second conductive semiconductor layer 127. You can do it.

The first insulating layer 131 may be formed by selecting at least one from the group consisting of SiO ₂ , SixOy, Si ₃ N ₄ , SixNy, SiOxNy, Al ₂ O ₃ , TiO ₂ , AlN, etc., but is not limited thereto. . The first insulating layer 131 may be formed as a single layer or multiple layers. For example, the first insulating layer 131 may be a distributed Bragg reflector (DBR) with a multilayer structure including Si oxide or Ti compound. However, the first insulating layer 131 is not necessarily limited to this and may include various reflective structures.

The first insulating layer 131 may include a second insulating portion 131b disposed inside the second recess 128 and a first insulating portion 131a disposed inside the first recess 129. You can. The second insulating part 131b and the first insulating part 131a may be connected to each other at the lower surface of the second conductive semiconductor layer 127.

The first insulating portion 131a may be disposed inside the first recess 129, and a through hole TH1 may be formed. The first electrode 142 may be disposed in the through hole TH1 of the first insulating portion 131a and electrically connected to the first conductive semiconductor layer 124.

The second insulating portion 131b is disposed entirely inside the second recess 128 to electrically insulate the first conductive layer 165, the second conductive layer 150, and the first conductive semiconductor layer 124. You can do it. Accordingly, little current may be distributed in the active layer 126 disposed outside the second recess 128. Additionally, since the second insulating portion 131b is disposed inside the second recess 128, oxidation of the side surfaces of the active layer 126 can be more effectively prevented.

The height h1 of the first recess 129 may be the same as the height h1 of the second recess 128. However, it is not necessarily limited to this, and the height h1 of the first recess 129 may be different from the height h1 of the second recess 128. In exemplary embodiments, the height h1 of the first recess 129 may be higher than the height h1 of the second recess 128 . For example, the first recess 129 should be formed in an area of the first conductive semiconductor layer 124 with low contact resistance with the first electrode 142, while the second recess 128 should be formed in the active layer 126. ), any height that can separate them may be sufficient. Conversely, the height h1 of the second recess 128 may be higher than the height h1 of the first recess 129. In this case, the moisture penetration path on the side of the light emitting structure 120 may be longer, thereby improving reliability.

The inclination angle θ ₁ of the first recess 129 may be the same as the inclination angle θ ₂ of the second recess 128 . However, it is not necessarily limited to this, and the inclination angles of the second recess 128 and the first recess 129 may be different. For example, the inclination angle of the second recess 128 may be greater than the inclination angle of the first recess 129 . In this case, the width of the second recess 128 may be reduced to increase the area of the active area IA1. Alternatively, the inclination angle of the second recess 128 may be smaller than the inclination angle of the first recess 129 . In this case, reliability can be improved by increasing the separation distance between the active area (IA1) and the inactive area (OA1) of the active layer 126.

The first electrode 142 may be disposed inside the first recess 129 and electrically connected to the first conductive semiconductor layer 124. Additionally, the second electrode 146 may be disposed on the lower surface of the second conductive semiconductor layer 127 and electrically connected to it.

The first electrode 142 and the second electrode 146 may be ohmic electrodes. The first electrode 142 and the second electrode 146 are made of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), and indium gallium zinc oxide (IGZO). ), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx/ITO, Ni/IrOx/Au, or Ni/IrOx/Au/ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, It may be formed including at least one of Ru, Mg, Zn, Pt, Au, and Hf, but is not limited to these materials. By way of example, the first electrode 142 may have a plurality of metal layers (eg, Cr/Al/Ni), and the second electrode 146 may be ITO.

The ratio of the area where the plurality of first electrodes 142 are in contact with the first conductive semiconductor layer 124 and the area where the second electrode 146 is in contact with the second conductive semiconductor layer 127 (of the first electrode Area: area of the second electrode) may be 1:3 to 1:9.

If the area ratio is greater than 1:9, the area of the first electrode becomes relatively small and the current dispersion characteristics may deteriorate. Additionally, when the area ratio is less than 1:3, the area of the second electrode becomes relatively small, which may deteriorate the current dispersion characteristics.

The first conductive layer 165 may include a plurality of protruding electrodes 165a that penetrate the first recess 129 and the second insulating layer 132 and are electrically connected to the plurality of first electrodes 142. there is. Accordingly, the first conductive layer 165 and the plurality of first electrodes 142 can be defined as first channel electrodes.

The first conductive layer 165 may be made of a material with excellent reflectivity. Exemplarily, the first conductive layer 165 may include metal such as Ti, Ni, or Al. For example, when the first conductive layer 165 includes aluminum, ultraviolet light emitted from the active layer 126 may be reflected upward.

The second conductive layer 150 may be electrically connected to the second electrode 146 and the bonding pad 166. Accordingly, the bonding pad 166, the second conductive layer 150, and the second electrode 146 may form one electrical channel. Accordingly, the second electrode 146 and the second conductive layer 150 may be defined as a second channel electrode.

The second conductive layer 150 is located below the second electrode 146, the bottom of the first insulating layer 131, the bottom of the second recess 128, the bottom of the light emitting structure 120, and the bonding pad 166. ) can be placed at the bottom of the. Additionally, the second conductive layer 150 may extend into the space D1 between the second electrode 146 and the first insulating layer 131 and be Schottky bonded to the first conductive semiconductor layer 124. . Accordingly, current dispersion efficiency can be improved.

The second conductive layer 150 is made of a material with good adhesion to the first insulating layer 131, and is made of at least one material selected from the group consisting of materials such as Cr, Ti, Ni, and Au, and alloys thereof. It can be made of a single layer or multiple layers.

The second conductive layer 150 may be disposed between the first insulating layer 131 and the second insulating layer 132. Accordingly, the second conductive layer 150 can be protected from penetration of external moisture or contaminants by the first insulating layer 131 and the second insulating layer 132. In addition, the second conductive layer 150 is disposed inside the semiconductor device, and its ends may be wrapped by the first and second insulating layers 131 and 132 so as not to be exposed on the outermost side of the semiconductor device. .

The second conductive layer 150 may include a first conductive region 150-1, a second conductive region 150-2, and a step portion 150-3. The first conductive area 150-1 may be disposed on the inside based on the second recess 128, and the second conductive area 150-2 may be placed on the outside based on the second recess 128. there is. That is, the first conductive area 150-1 may be placed in the active area IA1, and the second conductive area 150-2 may be placed in the inactive area OA1.

The step portion 150-3 may be disposed inside the second recess 128 and overlap the second recess 128 and the second insulating portion 131b in the vertical direction of the light emitting structure 120. The step portion 150-3 may have a shape corresponding to the inner shape of the second recess 128. Exemplarily, the step portion 150-3 may include inclined portions facing each other. Accordingly, the step portion 150-3 may be bent multiple times along the inner inclined surface of the second recess 128.

According to an embodiment, the second conductive layer 150 is bent by the step portion 150-3, so the area is relatively increased, and heat dissipation performance can be improved. In addition, the adhesive strength increases, thereby improving the problem of the second conductive layer 150 being peeled off from the light emitting structure 120.

The second insulating layer 132 may electrically insulate the first conductive layer 165 and the second conductive layer 150. The first insulating layer 131 and the second insulating layer 132 may be made of the same material or may be made of different materials.

The second insulating layer 132 may be disposed in the second recess 128 and the first recess 129, respectively. Accordingly, both the first insulating layer 131 and the second insulating layer 132 may be disposed inside the second recess 128 and the first recess 129. Therefore, even if a defect occurs in either the first insulating layer 131 or the second insulating layer 132, the remaining insulating layer can prevent external moisture and/or other contaminants from penetrating.

For example, when the first insulating layer 131 and the second insulating layer 132 are composed of one layer, defects such as cracks may easily propagate in the thickness direction. Accordingly, external moisture or contaminants may penetrate into the light emitting structure 120 through defects exposed to the outside.

However, according to the embodiment, since a separate second insulating layer 132 is disposed on the first insulating layer 131, it is difficult for defects formed in the first insulating layer 131 to propagate to the second insulating layer 132. You can. That is, the interface between the first insulating layer 131 and the second insulating layer 132 may serve to shield the propagation of defects.

The bonding layer 160 may be disposed along the shape of the lower surface of the light emitting structure 120 and the first recess 129. The bonding layer 160 may include a conductive material. Exemplarily, the bonding layer 160 may include a material selected from the group consisting of gold, tin, indium, aluminum, silicon, silver, nickel, and copper, or an alloy thereof.

The conductive substrate 170 may include a metal or semiconductor material. The conductive substrate 170 may be a metal with 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. Additionally, the first electrode 142 can receive current from the outside through the conductive substrate 170.

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

A passivation layer 180 may be disposed on the top and side surfaces of the light emitting structure 120. The thickness of the passivation layer 180 may be 200 nm or more and 500 nm or less. If it is 200 nm or more, the electrical and optical reliability of the device can be improved by protecting the device from external moisture or foreign substances. If it is less than 500 nm, the stress applied to the semiconductor device can be reduced, and the optical and electrical reliability of the semiconductor device can be improved. As this decreases or the process time for the semiconductor device increases, the problem that the unit cost of the semiconductor device increases can be improved.

Irregularities may be formed on the upper surface of the light emitting structure 120. These irregularities can improve the extraction efficiency of light emitted from the light emitting structure 120. The average height of the unevenness may vary depending on the wavelength of ultraviolet rays. In the case of UV-C, it has a height of about 300 nm to 800 nm, and light extraction efficiency can be improved when it has an average height of about 500 nm to 600 nm.

Referring to FIG. 11, the maximum height (h3) of the first conductive layer 165 from the lowermost surface 132a in the second recess 128 may be 0.4 μm to 0.6 μm. Additionally, the maximum height (h5) of the second insulating layer 132 from the lowermost surface 132a in the vertical direction (Z direction) in the second recess 128 may be 1.7 μm to 2.1 μm. Additionally, the maximum height (h6) of the first insulating layer 131 from the lowermost surface 132a in the vertical direction in the second recess 128 may be 2.4 μm to 2.6 μm. Additionally, the minimum horizontal width W5 of the upper surface of the second recess 128 may be 2 μm to 8 μm.

A first insulating layer 131, a second conductive layer 150, a second insulating layer 132, and a first conductive layer 165 may be disposed in the second recess 128. Therefore, even when the inactive area (OA1) is oxidized due to moisture infiltrating from the outside, the active area (IA1) can be prevented from being oxidized.

However, it is not necessarily limited to this, and the second conductive layer 150 may not be disposed in some areas of the second recess 128. In this case, the first insulating layer 131 and the second insulating layer 132 may function as one insulating layer.

For example, the second conductive layer 150 may be disposed in the second recess facing the bonding pad 166. This is because the second conductive layer 150 must extend to the outside of the light emitting structure 120 and be electrically connected to the bonding pad 166. However, the second conductive layer 150 may not be formed in the second recess 128 that does not face the bonding pad. According to this structure, the second conductive layer 150 is not disposed in some areas of the second recess 128, so even when the inactive area is oxidized and the first insulating layer is damaged, the second conductive layer 150 is not oxidized. can be prevented.

The second recess 128 may have a maximum separation distance from the outer surface of the light emitting structure 120 of 3 μm to 5 μm. This may vary depending on the size of the semiconductor device or light emitting structure 120.

FIG. 12 is a plan view of a semiconductor device according to the first embodiment of the present invention, and FIG. 13 is an enlarged view of portion C of FIG. 12.

Referring to FIGS. 12 and 13 , the second recess 128 may be disposed along the outer surface of the light emitting structure 120 to form a closed-loop in a plan view. Accordingly, the active layer of the light emitting structure 120 may be divided into an inactive area OA1 and an active area IA1 by the second recess 128 . However, it is not necessarily limited to this, and a plurality of second recesses 128 may be spaced apart from each other along the edge of the light emitting structure 120.

The inactive area OA1 may be an outer area of the second recess 128 , and the active area IA1 may be an inner area of the second recess 128 .

The active area IA1 may generate light with maximum intensity in the ultraviolet wavelength range by injecting electrons and holes through the first conductivity type semiconductor layer 124 and the second conductivity type semiconductor layer 127.

The inactive area (OA1) may be an area where electron and hole bonding does not occur. The inactive area (OA1) absorbs light irradiated from the active area or the outside, and the excited electrons may emit light through recombination. However, the light emission intensity of the inactive area OA1 may be very weak compared to the light emission intensity of the active area. Alternatively, the inactive area OA1 may not emit light at all. Accordingly, the light emission intensity of the inactive area OA1 may be lower than that of the active area IA1.

The light emitting structure 120 may be oxidized by external moisture or contaminants penetrating into the light emitting structure 120 from the outside. The active layer of an ultraviolet light-emitting device has a high Al composition, so it may be more vulnerable to oxidation. The second recess 128 may block oxidation from propagating to the active area IA1 when the inactive area OA1 is oxidized.

When the light-emitting structure 120 generates ultraviolet light, the current dispersion characteristics of the light-emitting structure 120 may be reduced because it has a high bandgap energy, and the effective light-emitting area P2 may be small. Accordingly, substantial current distribution can be achieved within the active area IA1. Accordingly, the semiconductor device can maintain sufficient light output even though it has the second recess 128.

The second conductive layer 150 may be entirely disposed in the active area IA1. Additionally, the second conductive layer 150 may be disposed entirely in the second recess 128 and the inactive area OA1, and may be disposed entirely in the second recess 128 in the area R1 facing the bonding pad 166. And may be placed only in the inactive area (OA1).

In addition, the second recess 128 limits the area in the active layer 126 where oxidation occurs due to moisture, etc. to the inactive area OA1, thereby protecting the active area IA1 where the effective light emitting area P2 is located, thereby reducing the amount of light. Output can be maintained.

The effective light emitting area (P2) can be defined as an area up to a boundary point where the current density is 40% or less based on the current density at the first electrode 142 with the highest current density. Additionally, it may be defined as an area that is 2 to 5 times the diameter of the first electrode 142. For example, a distance of 5 μm to 40 μm from the center of the inner recess 129a may be defined as a boundary point. However, the effective light emitting area P2 may vary depending on the level of injection current and the composition of Al.

The low current density area (P3) outside the effective light emitting area (P2) may hardly contribute to light emission due to its low current density. Accordingly, the ultraviolet semiconductor device can improve light output by disposing more first electrodes 142 in the low current density region P3 where the current density is low.

15 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention.

Referring to FIG. 15, the semiconductor device package includes a body 2 in which a groove 3 is formed, a semiconductor device 1 disposed in the body 2, and a semiconductor device 1 disposed in the body 2 and electrically connected to the semiconductor device 1. It may include a pair of lead frames 5a and 5b that are connected. The semiconductor device 1 may include all of the above-described configurations.

The body 2 may include a material or coating layer that reflects ultraviolet light. The body 2 can be formed by stacking a plurality of layers 2a, 2b, 2c, 2d, and 2e. The plurality of layers 2a, 2b, 2c, 2d, and 2e may be made of the same material or may include different materials.

The groove 3 becomes wider as it moves away from the semiconductor device, and a step 3a may be formed on the inclined surface.

Referring to FIG. 16, the semiconductor device 10 may be placed on the first lead frame 5a and connected to the second lead frame 5b by a wire. At this time, the first lead frame 5a and the second lead frame 5b may be arranged to surround the side surface of the semiconductor device 10.

The light-transmitting layer 4 may cover the groove 3. The light transmitting layer 4 may be made of glass, but is not necessarily limited thereto. The light transmitting layer 4 is not particularly limited as long as it is made of a material that can effectively transmit ultraviolet light. The interior of the groove 3 may be empty space.

Semiconductor devices can be applied to various types of light source devices. For example, the light source device may include a sterilizing device, a curing device, a lighting device, a display device, and a vehicle lamp. In other words, the semiconductor device can be applied to various electronic devices that are placed in a case and provide light.

The sterilizing device is equipped with a semiconductor device according to the embodiment and can sterilize a desired area. The sterilizing device may be applied to household appliances such as water purifiers, air conditioners, and refrigerators, but is not necessarily limited thereto. In other words, the sterilization device can be applied to a variety of products that require sterilization (e.g., medical devices).

Exemplarily, a water purifier may be equipped with a sterilizing device according to an embodiment to sterilize circulating water. The sterilizing device may be placed at a nozzle or outlet through which water circulates and irradiate ultraviolet rays. At this time, the sterilizing device may include a waterproof structure.

The curing device is equipped with a semiconductor device according to the embodiment and can cure various types of liquids. Liquid can be a concept that includes all various substances that harden when irradiated with ultraviolet rays. For example, the curing device can cure various types of resin. Alternatively, the curing device may be applied to harden beauty products such as nail polish.

The lighting device may include a light source module including a substrate and the semiconductor device of the embodiment, a heat dissipation unit that dissipates heat from the light source module, and a power supply unit that processes or converts an electrical signal provided from the outside and provides the light source module to the light source module. Additionally, the lighting device may include a lamp, head lamp, or street lamp.

The display device may 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, reflector, light emitting module, light guide plate, and optical sheet may constitute a backlight unit.

The reflector is disposed on the bottom cover, and the light emitting module can emit light. The light guide plate is disposed in front of the reflector and guides the light emitted from the light emitting module to the front, and the optical sheet includes a prism sheet, etc. and may be disposed in front of the light guide plate. A display panel may be disposed in front of the optical sheet, an image signal output circuit may supply an image signal to the display panel, and a color filter may be disposed in front of the display panel.

Although the above description focuses on the examples, this is only an example and does not limit the present invention, and those skilled in the art will be able to You will see that various variations and applications are possible. For example, each component specifically shown in the examples can be modified and implemented. And these variations and differences in application should be construed as being included in the scope of the present invention as defined in the appended claims.

Claims (20)

A first conductive semiconductor layer containing Al;
a second conductive semiconductor layer containing Al; and
an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer and containing Al; Including,
When primary ions collide with the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer, Al ions are released from each of the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer,
The first point where the Al ion intensity is lowest,
A second point disposed to be spaced apart from the first point in the first direction and having the highest peak of Al ion intensity,
A third point having the lowest Al ion intensity in a region spaced apart from the second point in the first direction,
A fourth point having the strongest Al ion intensity peak between the second point and the third point,
A fifth point where Al ion intensity is the greatest in a region spaced apart from the third point in the first direction,
It is disposed between the third point and the fifth point, and includes a sixth point that is greater than the Al ion strength of the third point and smaller than the Al ion strength of the fifth point,
The first direction is a direction from the second conductive semiconductor layer to the active layer,
The difference between the Al ion strengths of the second point and the third point is greater than the difference between the Al ion strengths of the first point and the third point,
The second conductive semiconductor layer includes a first region disposed between the first point and the second point,
The active layer includes a second region disposed between the second point and the fourth point,
The first conductive semiconductor layer includes a third region disposed between the fourth point and the fifth point,
The third area includes a 3-1 area and a 3-2 area,
The 3-1 region has at least one point having an Al ion strength equal to the Al ion strength of the third point,
The 3-2 region has at least one point having the same Al ion strength as the Al ion strength of the 6th point,
A ratio of the width of the 3-1 region in the first direction to the width of the 3-2 region in the first direction is 1:2 to 1:4.
According to paragraph 1,
The Al ion intensity has a plurality of peaks located between an increasing region and a decreasing region along the first direction,
A semiconductor device wherein the plurality of peaks are local maximum points of Al ions.
According to paragraph 2,
The first to sixth points are points that appear in the spectrum of Al ion intensity measured by TOF-SIMS,
The first direction is a semiconductor device in which the primary ion intensity is irradiated.
According to paragraph 3,
The primary ions include O ²⁺ , Cs ⁺ , Bi ⁺ ,
The TOF-SIMS measurement conditions include an acceleration voltage of 20 to 30 keV and an irradiation current of 0.1 pA to 5.0 pA for a semiconductor device.
According to paragraph 4,
A semiconductor device wherein the Al ion intensity of the 3-1 region is 98% to 102% of the Al ion intensity of the third point.
According to paragraph 1,
It includes a light extraction area having an Al ion intensity equal to the Al ion intensity of the fifth point,
The light extraction area is a semiconductor device having irregularities on the surface.
According to claim 1 or 6,
A first electrode electrically connected to the first conductive semiconductor layer, and
It includes a second electrode electrically connected to the second conductive semiconductor layer,
The first electrode is electrically connected to the third point,
The second electrode is a semiconductor device electrically connected to the first point.
According to claim 1 or 6,
A semiconductor device wherein the Al ion strength at the fifth point and the Al ion strength at the second point are the same.
According to claim 1 or 6,
A semiconductor device wherein the Al ion strength at the fifth point and the Al ion strength at the second point are different from each other.
According to clause 9,
A semiconductor device wherein the Al ion strength at the fifth point is greater than the Al ion strength at the second point.
According to clause 9,
A semiconductor device wherein the Al ion strength at the fifth point is smaller than the Al ion strength at the second point.
According to paragraph 4,
The second region includes a plurality of peaks and a plurality of valleys respectively disposed between the plurality of peaks,
A semiconductor device in which the wavelength of light with the highest intensity among the wavelengths of light emitted from the plurality of valleys is 100 nm to 320 nm.
According to paragraph 4,
The first region includes Mg, and the third region includes Si.
In clause 7,
A plurality of recesses penetrating through a portion of the second conductivity type semiconductor layer, the active layer, and the first conductivity type semiconductor layer,
The plurality of recesses are disposed in the first area, the second area, and the 3-1 area,
The first electrode is a semiconductor device disposed within the plurality of recesses.
According to clause 14,
The ratio of the area of the lower surface of the second conductive semiconductor layer and the area of the plurality of recesses is 1:0.1 to 1:0.3.
According to clause 15,
The second electrode is in contact with the second conductive semiconductor layer,
A semiconductor device wherein the ratio of the area of the upper surface of the second electrode to the area of the lower surface of the second conductive semiconductor layer is 1:2 to 1:3.
According to clause 16,
A semiconductor device wherein the ratio of the area of the top surface of the first electrode to the area of the top surface of the second electrode is 1:3 to 1:9.
According to clause 17,
conductive substrate; and
and a bonding pad disposed on the conductive substrate and spaced apart from the first to third regions,
The first to third regions are disposed on the conductive substrate,
The bonding pad is electrically connected to the second electrode,
The conductive substrate is a semiconductor device electrically connected to the first electrode.
According to clause 18,
The plurality of recesses include a plurality of first recesses in which the first electrode is disposed, and a second recess surrounding the plurality of first recesses,
A semiconductor device in which an insulating layer is in contact with the front surface of the first conductive semiconductor layer constituting the upper surface of the second recess.
According to clause 19,
The semiconductor device wherein the active layer is separated into an active area and a non-active area by the second recess, and the non-active area is electrically insulated from the second electrode and the first electrode.

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