KR20190090235A - Semiconductor device - Google Patents

Abstract

The present invention provides a semiconductor element with increased light output. According to an embodiment of the present invention, the semiconductor element comprises a semiconductor structure including: a buffer layer including aluminum; a first conductive semiconductor layer including aluminum; an active layer including aluminum; and a second conductive semiconductor layer including aluminum. The semiconductor structure emits a secondary ion including an aluminum ion when radiating a primary ion. Ionic strength of the aluminum emitted from the buffer layer has first maximum strength and first minimum strength. The ionic strength of the aluminum emitted from the first conductive semiconductor layer has second maximum strength and second minimum strength. The ionic strength of the aluminum emitted from the second conductive semiconductor layer has third maximum strength and third minimum strength. The first maximum strength is the largest aluminum ion strength in the semiconductor structure. The third minimum strength is the smallest aluminum ion strength in the semiconductor structure. A ratio between the first maximum strength to the third minimum strength is 1 : 0.3 to 1 : 0.6.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

Embodiments relate to semiconductor devices.

Semiconductor devices including compounds such as GaN and AlGaN have many merits such as wide and easy bandgap energy, and can be used variously as light emitting devices, light receiving devices, and various diodes.

Particularly, a light emitting device such as a light emitting diode or a laser diode using a semiconductor material of Group 3-5 or 2-6 group semiconductors can be applied to various devices such as a red, Blue, and ultraviolet rays. By using fluorescent materials or combining colors, it is possible to realize a white light beam with high efficiency. Also, compared to conventional light sources such as fluorescent lamps and incandescent lamps, low power consumption, , Safety, and environmental friendliness.

In addition, when a light-receiving element such as a photodetector or a solar cell is manufactured using a semiconductor material of Group 3-5 or Group 2-6 compound semiconductor, development of a device material absorbs light of various wavelength regions to generate a photocurrent , It is possible to use light in various wavelength ranges from the gamma ray to the radio wave region. It also has advantages of fast response speed, safety, environmental friendliness and easy control of device materials, so it can be easily used for power control or microwave circuit or communication module.

Accordingly, the semiconductor device can be replaced with a transmission module of an optical communication means, a light emitting diode backlight replacing a cold cathode fluorescent lamp (CCFL) constituting a backlight of an LCD (Liquid Crystal Display) display device, White light emitting diodes (LEDs), automotive headlights, traffic lights, and gas and fire sensors. In addition, semiconductor devices can be applied to high frequency application circuits, other power control devices, and communication modules.

In particular, a light emitting device that emits light in the ultraviolet wavelength range can be used for curing, medical use, and sterilization by curing or sterilizing action.

Recently, ultraviolet light emitting devices have been actively researched, but ultraviolet light emitting devices are still difficult to realize as flip chips. In the case of forming a GaN thin film between a P semiconductor layer and an electrode for an ohmic characteristic, .

The embodiment provides a semiconductor device with improved ohmic characteristics.

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

Further, a flip chip ultraviolet light emitting device is provided.

The problems to be solved in the embodiments are not limited to these, and the objects and effects that can be grasped from the solution means and the embodiments of the problems described below are also included.

A semiconductor device according to an embodiment of the present invention includes a buffer layer including aluminum, a first conductive semiconductor layer including aluminum, an active layer including aluminum, and a second conductive semiconductor layer including aluminum Wherein the semiconductor structure emits secondary ions containing aluminum ions upon primary ion irradiation and the aluminum ion intensity emitted from the buffer layer has a first maximum intensity and a first minimum intensity, Wherein the aluminum ion intensity emitted from the conductive type semiconductor layer has a second maximum intensity and a second minimum intensity, and the aluminum ion intensity emitted from the second conductivity type semiconductor layer has a third maximum intensity and a third minimum intensity, Wherein the first maximum intensity is highest in the aluminum ion intensity in the semiconductor structure and the third minimum intensity is in the aluminum structure in the semiconductor structure And the ratio of the first maximum intensity to the third minimum intensity satisfies 1: 0.3 to 1: 0.6.

The third maximum intensity may be greater than the second maximum intensity, the second minimum intensity, and the first minimum intensity.

The second maximum intensity may be greater than the first minimum intensity, and the first minimum intensity may be greater than the second minimum intensity.

The aluminum ion intensity emitted from the buffer layer may have a first intermediate intensity having the highest intensity between the first minimum intensity and the second minimum intensity.

The first intermediate intensity may be greater than the second maximum intensity.

The first medium intensity may be less than the first maximum intensity.

The aluminum ion intensity emitted from the active layer may include a plurality of peaks and a plurality of valleys, and the plurality of peaks may be smaller than the first maximum intensity, the second maximum intensity, and the third maximum intensity.

The second conductive semiconductor layer may include a barrier layer, a P-type conductivity-type semiconductor layer, and a surface layer.

The surface layer may comprise a first dopant and a second dopant.

The secondary ion may include a first dopant ion and a second dopant ion.

The first dopant ion concentration may include a first doping concentration emitted from the first conductivity type semiconductor layer, a second doping concentration emitted from the active layer, and a third doping concentration emitted from the second conductivity type semiconductor layer .

The third doping concentration may be greater than the first doping concentration and the second doping concentration.

A fourth doping concentration disposed between the first doping concentration and the second doping concentration and a fifth doping concentration disposed between the second doping concentration and the third doping concentration, The fifth doping concentration may be smaller than the first through third doping concentrations.

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

Further, light absorption can be suppressed in the semiconductor device, and the light output can be improved.

The various and advantageous advantages and effects of the present invention are not limited to the above description, and can be more easily understood in the course of describing a specific embodiment of the present invention.

1 is a conceptual view of a semiconductor structure according to a first embodiment of the present invention,
2 is a graph showing the aluminum composition of the semiconductor structure according to the first embodiment of the present invention,
3 is a schematic diagram of a semiconductor structure according to the first embodiment of the present invention,
4 is a graph showing the ionic strength of aluminum,
5 is a view showing a first dopant ion concentration and a second dopant ion concentration,
Fig. 6 is a first modification of Fig. 3,
Fig. 7 is a second modification of Fig. 3,
8 is a conceptual view of a semiconductor device according to the first embodiment of the present invention,
9 is a conceptual view of a semiconductor device according to a second embodiment of the present invention,
10 is a conceptual view of a semiconductor device according to a third embodiment of the present invention,
11 is a conceptual diagram of a semiconductor device package according to an embodiment of the present invention.

The embodiments may be modified in other forms or various embodiments may be combined with each other, and the scope of the present invention is not limited to each embodiment described below.

Although not described in the context of another embodiment, unless otherwise described or contradicted by the description in another embodiment, the description in relation to another embodiment may be understood.

For example, if the features of configuration A are described in a particular embodiment, and the features of configuration B are described in another embodiment, even if the embodiment in which configuration A and configuration B are combined is not explicitly described, It is to be understood that they fall within the scope of the present invention.

In the description of the embodiments, in the case where one element is described as being formed "on or under" another element, the upper (upper) or lower (lower) or under are all such that two elements are in direct contact with each other or one or more other elements are indirectly formed between the two elements. Also, when expressed as "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

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

1 and 2, a semiconductor device according to an embodiment includes a buffer layer 121, a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, and a first conductive semiconductor layer 124 And an active layer 126 disposed between the second conductive semiconductor layer 127 and the second conductive semiconductor layer 127.

The semiconductor structure 120 according to the embodiment of the present invention can output light in the ultraviolet wavelength range. For example, the semiconductor structure 120 can output light UV-A at the near ultraviolet wavelength band, output light UV-B at the far ultraviolet wavelength band, and light UV-C at the deep ultraviolet wavelength band Can be output. The wavelength range may be determined by the aluminum composition ratio of the semiconductor structure 120.

Illustratively, the near-ultraviolet light (UV-A) may have a peak wavelength in the range of 320 nm to 420 nm, the far ultraviolet light (UV-B) may have a peak wavelength in the range of 280 nm to 320 nm, The light (UV-C) at deep ultraviolet wavelength band may have a peak wavelength in the range of 100 nm to 280 nm.

When the semiconductor structure 120 is for emitting light in the ultraviolet wavelength range, the respective semiconductor layers of the semiconductor structure 120 In _x1 Al _y1 Ga _{1 -x1-} containing aluminum _y1 N (0≤x1≤1, 0 _<y1 1, 0? X1 + y1? 1). Here, the composition of Al can be represented by the ratio of the total atomic weight including the In atomic weight, the Ga atomic weight, and the Al atomic weight to the Al atomic weight. For example, when the Al composition is 40%, the composition of Ga may be 60%, and the composition ratio may be expressed by Al ₄₀ Ga ₆₀ N.

In addition, in the description of the embodiment, the meaning of the composition being low or high can be understood as a difference (% point) of the composition% of each semiconductor layer. For example, when the aluminum composition of the first semiconductor layer is 30% and the aluminum composition of the second semiconductor layer is 60%, the aluminum composition of the second semiconductor layer is 30% higher than the aluminum composition of the first semiconductor layer Can be expressed.

The buffer layer 121 may be formed of a compound semiconductor such as Group III-V or Group II-VI. Buffer layer 121 contains a semiconductor material, for example, having a compositional formula of _{In x1 Al y1 Ga 1 -x1- y1} N (0≤x1≤1, 0 <y1≤1, 0≤x1 + y1≤1) AlGaN, AlN , InAlGaN, and the like.

The buffer layer 121 may include a plurality of layers to improve crystallinity or mitigate lattice mismatch. The buffer layer 121 may not be doped with a dopant, but may be intentionally or unintentionally doped in some regions.

The first buffer layer 121a may have the highest aluminum composition. Illustratively, the first buffer layer 121a may be AlN, but is not limited thereto and may be AlGaN having a high aluminum composition. The thickness of the first buffer layer 121a may be 100 nm to 4000 nm, but is not limited thereto.

The second buffer layer 121b may be disposed on the first buffer layer 121a. The second buffer layer 121b may have a lower aluminum composition than the first buffer layer 121a. The aluminum composition of the second buffer layer 121b may be smaller than the aluminum composition of the first buffer layer 121a and may be larger than the aluminum composition of the third buffer layer 121c. Illustratively, the second buffer layer 121b may be AlGaN, but is not limited thereto.

The third buffer layer 121c may have a structure in which a first sublayer (not shown) and a second sublayer (not shown) are alternately stacked. Illustratively, the first sub-layer may be AlN or AlGaN and the second sub-layer may be AlGaN. When the first sub-layer and the second sub-layer are both AlGaN, the aluminum composition of the first sub-layer may be higher than that of the second sub-layer. The first sub-layer and the second sub-layer may be about 40 to 60 pairs, but are not necessarily limited thereto.

The third buffer layer 121c can mitigate the stress applied to the semiconductor layer. However, the present invention is not limited thereto, and the third buffer layer 121c may function as a separation layer.

The second sub-layer having a relatively small aluminum composition can be decomposed by absorbing laser light irradiated to the semiconductor structure 120 during an LLO (Laser Lift-off) process. Accordingly, the first buffer layer 121a and the growth substrate can be removed from the semiconductor structure 120. [ To this end, the aluminum composition of the second sub-layer may be low enough to absorb the LLO laser. Illustratively, the aluminum composition of the second sub-layer may be between 30% and 60% of the aluminum composition of the first sub-layer, but is not so limited, and the aluminum composition may be configured to have a bandgap corresponding to the LLO laser wavelength.

The fourth buffer layer 121d may have a higher aluminum composition than the third buffer layer 121c. The fourth buffer layer 121d can improve the crystallinity of the semiconductor structure 120 by raising the aluminum composition again. Illustratively, the aluminum composition of the fourth buffer layer 121d may be the same as the aluminum composition of the second buffer layer 121b. The fifth buffer layer 121e may have a lower aluminum composition than the fourth buffer layer 121d. The fourth buffer layer 121d and the fifth buffer layer 121e may be AlGaN, but are not limited thereto.

The first conductive semiconductor layer 124 may be formed of a compound semiconductor such as Group III-V or Group II-VI, and the first dopant may be doped. The first conductive semiconductor layer 124 may be a semiconductor material having a composition formula of In _x1 Al _y1 Ga _{1 -x1 -y1} N (0? _{X1? 1} , 0 < _{y1? 1} , 0? X1 + y1? For example, AlGaN, AlN, InAlGaN, and the like. 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 conductivity type 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. have.

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 or lower than that of the first sub-semiconductor layer 124a.

The aluminum composition of the fourth sub semiconductor layer 124d is 40% to 70% when the semiconductor structure 120 emits light UV-C at the deep ultraviolet wavelength band, and the aluminum of the first sub semiconductor layer 124a The composition may be from 50% to 80%.

When the aluminum composition of the fourth sub-semiconductor layer 124d is 40% or more, the absorption efficiency of light (UV-C) emitted from the deep ultraviolet wavelength band emitted from the active layer 126 may be lowered and the light extraction efficiency may be improved. Further, 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 in the fourth sub-semiconductor layer 124d can be ensured.

Further, when the aluminum composition of the first sub-semiconductor layer 124a is 50% or more, the absorption efficiency of light (UV-C) emitted from the deep ultraviolet wavelength band emitted from the active layer 126 can be lowered, The current injection characteristics into the active layer 126 and the current diffusion characteristics in the first sub semiconductor layer 124a can be ensured.

In addition, the aluminum composition of the first sub semiconductor layer 124a may be higher than the aluminum composition of the fourth sub semiconductor layer 124d. In this case, it is more advantageous to extract light from the active layer 126 to the outside of the semiconductor structure 120 due to a difference in refractive index, so that the light extraction efficiency of the semiconductor structure 120 can 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 structure, since the third sub semiconductor layer 124c is disposed after the thickness of the first sub semiconductor layer 124a having a high aluminum composition is sufficiently secured, 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 the aluminum composition of the first conductivity type semiconductor layer 124 and the second conductivity type semiconductor layer 127. The third sub-semiconductor layer 124c may absorb the laser beam irradiated to the semiconductor structure 120 during the LLO (Laser Lift-off) process to prevent the active layer 126 from being damaged. Therefore, the optical characteristics and the electrical characteristics of the semiconductor device can be improved.

The thickness of the third sub-semiconductor layer 124c and the aluminum composition 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 in the LLO process, and 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 % 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 may be formed by reducing the energy of the first carrier injected in the direction of the active layer 126 from the first conductivity type semiconductor layer 124 to reduce the energy density of the first and second carriers recombined in the active layer 126 Balance can be achieved. Therefore, the light emitting efficiency can be improved and the optical output characteristic of the semiconductor device can be improved. 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. Illustratively, 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 type semiconductor layer 124 and holes (or electrons) injected through the second conductive type semiconductor layer 127 meet. The active layer 126 transitions to a low energy level as electrons and holes recombine, and can generate light having ultraviolet wavelengths.

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 _{x 2} Al _{y 2} Ga _{1 -x 2 -y 2} N (0? X _{2 ? 1} , 0 < _{y 2 ? 1} , 0? X 2 + y 2? 1) . The composition of the aluminum layer in the well layer 126a may vary depending on the wavelength of light emitted.

The second conductive semiconductor layer 127 may be disposed on the active layer 126 and may be formed of a compound semiconductor such as a group III-V or II-VI group. In the second conductive semiconductor layer 127, The dopant can be doped.

A second conductive semiconductor layer 127 is a semiconductor material having a compositional 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, AlGaInP.

When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, the second conductivity type 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 conductive semiconductor layer 127. The blocking layer 129 blocks the flow of carriers supplied from the first conductivity type semiconductor layer 124 to the second conductivity type semiconductor layer 127 and prevents the probability of recombination of electrons and holes in the active layer 126 .

The energy band gap of the blocking layer 129 may be greater than the energy band gap of the active layer 126 and the second conductivity type semiconductor layer 127. The blocking layer 129 may be defined as a part of the second conductive type semiconductor layer 127 because the second dopant is doped. That is, the second conductivity type semiconductor layer 127 may be defined as including a P-type semiconductor layer and a blocking layer 129.

The barrier layer 129 may be formed of a semiconductor material having a composition formula of In _{x 1} Al _{y 1} Ga _{1 -x 1 -y 1} N (0 _{≦ x 1 ≦ 1} , 0 _{≦ y 1 ≦ 1} , 0 _{≦ x 1 + y 1 ≦ 1} ) AlN, InAlGaN, and the like, but is not limited thereto.

The first conductive semiconductor layer 124, the active layer 126, the blocking layer 129, and the second conductive semiconductor layer 127 may all include aluminum. Therefore, the first conductive semiconductor layer 124, the active layer 126, the blocking layer 129, and the second conductive semiconductor layer 127 may have an AlGaN, InAlGaN, or AlN composition.

The barrier layer 129 may have an aluminum composition of 50% to 100%. If the aluminum composition of the barrier layer 129 is 50% or more, the barrier layer 129 may have sufficient energy barrier to block movement of the 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 first barrier layer 129a may have a higher aluminum composition 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 barrier layer 129a may be 80% to 100%. Accordingly, the first barrier layer 129a may be a portion having the highest Al composition in the semiconductor structure 120. [ The first blocking layer 129a may be AlGaN or AlN. Alternatively, the first blocking layer 129a may be a super lattice 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 (e.g. electrons), the thickness of the first blocking layer 129a can be set to 0.1 nm or more. The thickness of the first blocking layer 129a may be 4 nm or less in order to secure the efficiency of injecting carriers (e.g., holes) into the active layer 126 from the second conductivity type semiconductor layer 127.

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 include a dopant. Accordingly, the third blocking layer 129c may prevent the dopant from diffusing from the second conductivity type semiconductor layer 127 to the active layer 126. [

The second conductivity type 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 may have a relatively uniform aluminum composition to improve hole injection efficiency or improve 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. Illustratively, 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, the resistance in the horizontal direction may decrease and the current diffusion efficiency may be improved. When the thickness of the sixth sub semiconductor layer 127b is smaller than 50 nm, the path through which the light incident on the sixth sub semiconductor layer 127b from the active layer 126 is absorbed can be shortened, The efficiency can be improved.

The aluminum composition of the sixth sub semiconductor layer 127b may be higher than the aluminum composition of the well layer 126a. The aluminum composition of the well layer 126a for producing deep ultraviolet or far ultraviolet light may be about 20% to 60%. Therefore, the aluminum composition of the sixth sub-semiconductor layer 127b may be greater than 40% and less than 80%. Illustratively, 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 probability of the sixth sub-semiconductor layer 127b absorbing the ultraviolet light is high, have.

The seventh sub-semiconductor layer 127c may be a surface layer of the semiconductor structure 120 in contact with the second electrode. The current can be injected into the seventh sub-semiconductor layer 127c through the second electrode, and the current injection efficiency can 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 at least one of an ohmic contact, a Schottky contact, or a tunnel effect, but the present invention is not limited thereto.

The seventh sub-semiconductor layer 127c may be formed of a compound semiconductor such as group III-V, group II-VI, or the like, and the first dopant may be doped. The seventh sub-semiconductor layer 127c is a semiconductor material having a composition formula of In _x1 Al _y1 Ga _{1 -x1 -y1} N (0? _{X1? 1} , 0 < _{y1 ?} , 0? X1 + y1? For example, AlGaN, InAlGaN, AlN, and the like. 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. The first dopant may be intentionally doped while the second dopant may be the second dopant diffused into the second conductive semiconductor layer 127. However, the present invention is not limited thereto, and the seventh sub-semiconductor layer 127c may be intentionally doped with the first dopant and the second dopant for activating the carrier.

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

At this time, the concentration ratio of the first dopant and the second dopant doped to 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, the ohmic resistance can be lowered by the tunnel effect.

Illustratively, the first dopant concentration of the seventh sub-semiconductor layer 127c may be between 1 × 10 ¹⁸ cm ^-3 and 2 × 10 ²⁰ cm ^-3 . The concentration of the second dopant in the seventh sub-semiconductor layer 127c may be 1 x 10 ¹⁹ cm ^-3 to 2 x 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 conductivity type 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. When the thickness of the seventh sub semiconductor layer 127c is thicker than 10 nm, there is a problem that the carrier injection efficiency is lowered. Therefore, the thickness of the seventh sub-semiconductor layer 127c may be smaller than that of the first conductivity type semiconductor layer 124 and the second conductivity type semiconductor layer 127. [

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

The closer to the surface the seventh sub-semiconductor layer 127c, the lower the aluminum composition can be. The decrease width of the sixth sub semiconductor layer 127b may be different from or the same as the decrease width of the seventh sub semiconductor layer 127c.

According to the 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, the present invention is not limited to this, and the seventh sub-semiconductor layer 127c may have an improved injection efficiency of holes due to the tunnel effect, so that the aluminum composition may be controlled to be higher than that of the well layer 126a or higher than that of the well layer 126a .

FIG. 3 is a SIMS (Secondary Ion Mass Spectroscopy) data of a semiconductor structure according to the first embodiment of the present invention, FIG. 4 is a diagram showing the ionic strength of aluminum, FIG. 6 is a first modification of FIG. 3, and FIG. 7 is a second modification of FIG. 3.

Referring to FIG. 3, the semiconductor structure 120 may include aluminum (Al), gallium (Ga), a first dopant, a second dopant, and a second dopant as the distance from the first conductivity type semiconductor layer 124 to the second conductivity type semiconductor layer 127 increases. Can be changed. The first dopant may be silicon (Si) and the second dopant may be magnesium (Mg) but is not necessarily limited thereto.

Sims (SIMS) data may be analytical data by time-of-flight secondary ion mass spectrometry (TOF-SIMS).

SIMS data can be analyzed by counting the number of secondary ions emitted by irradiating the surface of the target with primary ions. In this case, the primary ion may be selected from O ₂ ⁺ , Cs ⁺ Bi ^+, etc., and the acceleration voltage may be adjusted within 20 to 30 keV, the irradiation current may be controlled from 0.1 pA to 5.0 pA, May be 20 nm x 20 nm.

The SIMS data can be acquired by gradually etching the surface of the second conductivity type semiconductor layer 127 in the direction of the first conductivity type semiconductor layer 124 from the surface E0 have. The secondary ion may be a member constituting the semiconductor layer. Illustratively, the secondary ion can be, but is not necessarily limited to, aluminum, gallium, a first dopant, and a second dopant.

The results of the sim- ulation analysis can be interpreted as the intensity of the secondary ion or the spectrum of the doping concentration of the secondary ion within 5% in the analysis of secondary ion intensity or doping concentration, And may include noise having a magnitude of 1.05 times. Thus, the phrase "same / same" may mean a specific secondary ion intensity or a noise comprising no less than 0.95 times to no more than 1.05 times the doping concentration.

Illustratively, if there is a peak adjacent to the first point but has a magnitude of 0.95 to 1.05 times the first point, it can be understood that the surrounding peak has the same intensity as the aluminum strength at the first point. In this case, the doping concentration, ionic strength, and peak of a certain period may mean the highest point.

The ionic strength according to the embodiment can be increased or decreased depending on the measurement conditions. However, as the intensity of the primary ion increases, the intensity graph of the secondary ion (aluminum ion) also increases as a whole. When the intensity of the primary ion decreases, the intensity graph of the secondary ion (aluminum ion) may also decrease overall. Therefore, the change in the ion intensity in the thickness direction may be similar even if the measurement conditions are changed.

3 and 4, it can be seen that the secondary ionic strength (e.g., aluminum) in the semiconductor structure 120 has the highest 12th ionic strength P12 and the lowest third ionic strength P3 ) Can be defined.

The twelfth ionic strength P12 may be disposed farthest from the surface E0 of the semiconductor structure. In addition, a buffer layer containing the twelfth ionic strength (P12) may have an air gap between the active layer and the substrate. At this time, the light emitted from the active layer is scattered in the air gap, so that the light extraction efficiency can be improved.

The first ionic strength P1 may be highest between the third ionic strength P3 and the twelfth ionic strength P12. The twelfth ionic strength P12 and the first ionic strength P1 may be disposed apart from each other. The distance between the first ion intensity P1 and the third ion intensity P3 may be smaller than the distance between the first ion intensity P1 and the twelfth ion intensity P12.

The second ionic strength P 2 may be disposed between the first ionic strength P 1 and the twelfth ionic strength P 12. The second ionic strength P 2 may be disposed apart from the first ionic strength P 1 and the twelfth ionic strength P 12.

The second ionic strength P 2 may be located closer to the first ionic strength P 1 than the twelfth ionic strength P 12. Specifically, the second ionic strength P 2 may be highest between the fourth ionic strength P 4 and the first ionic strength P 1, which is the lowest among the ionic strengths of the first conductivity type semiconductor layer 124.

The active layer 126 may be disposed between the first ion intensity P1 and the second ion intensity P2 and may include a plurality of peaks P61 and a valley P62. The ionic strength of the peak P61 may be larger than the ionic strength of the valley P62. Peak P61 may be the ionic strength of barrier layer 126b and valley P62 may be the ionic strength of well layer 126a.

The ion intensity of the peak P61 may be smaller than the first ion intensity P1 and the second ion intensity P2. Therefore, the energy of the carrier injected into the active layer from the semiconductor layer spaced apart from the second ion intensity P2 in the first direction D2 is lowered to prevent the first ion intensity P1 from falling in the direction D1, Can be improved.

The fourth ionic strength P4 may be lowest in the interval between the first ionic strength P1 and the twelfth ionic strength P12. Therefore, the active layer 126 can be prevented from penetrating the laser, thereby preventing the active layer 126 from being damaged by the LLO process.

The fifth ionic strength P5 may be disposed between the second ionic strength P2 and the fourth ionic strength P4. The fifth ionic strength P5 may be less than the second ionic strength P2 and greater than the fourth ionic strength P4. The interval between the second ion intensity P 2 and the fourth ion intensity P 4 may have a relatively uniform fifth ionic strength P 5.

The ninth ionic strength P9 can be the highest in the interval between the fourth ionic strength P4 and the twelfth ionic strength P12. The ninth ionic strength P9 may be equal to or higher than the neighboring eighth ionic strength P8. According to the embodiment, the ninth ionic strength P9, the eighth ionic strength P8, the seventh ionic strength P7, and the fourth ionic strength P4 can be sequentially decreased in the first direction D1 have. Therefore, it is possible to prevent the deterioration of the crystallinity by gradually lowering the intensity from the ninth ionic strength P9 to the fourth ionic strength P4.

The tenth ionic strength (P10) may be lowest in the interval between the ninth ionic strength (P9) and the twelfth ionic strength (P12). The tenth ionic strength P10 may be greater than the fourth ionic strength P4, but is not limited thereto. Illustratively, the tenth ionic strength P10 may be equal to or less than the fourth ionic strength P4.

The first ionic strength P1 may be the highest in the second conductivity type semiconductor layer 127. [ Therefore, it is possible to prevent the first carrier from recombining with the second carrier in the second conductivity type semiconductor layer 127 in a non-luminescent manner. Therefore, the light output of the semiconductor element can be improved. The first ionic strength P1 may be the ionic strength of the first blocking layer 129a, but is not limited thereto.

The third ionic strength P3 may have the lowest ionic strength in the semiconductor structure 120. The third ionic strength P3 may be the ionic strength at a point at which the semiconductor structure 120 contacts the second electrode. According to the embodiment, since the AlGaN composition at the surface of the semiconductor structure 120 reduces the absorption rate of ultraviolet light, the light extraction efficiency can be improved and the resistance between the second electrode and the third ion intensity P3 can be reduced The optical characteristics and electrical characteristics of the light emitting device can be improved.

The first ionic strength P 1 may be the maximum ionic strength of the second conductivity type semiconductor layer 127 (third maximum intensity) and the third ionic strength P 3 may be the minimum ionic strength of the second conductivity type semiconductor layer 127 Ionic strength (third minimum intensity).

The aluminum ion intensity emitted from the first conductivity type semiconductor layer 124 may have second, fourth, fifth, seventh, and eighth ion intensities P2, P4, P5, P7, and P8. At this time, the second ion intensity P 2 and / or the eighth ionic strength P 8 may be the maximum ionic strength (first maximum intensity) of the first conductivity type semiconductor layer 124, May be the minimum ionic strength (second minimum intensity) of the first conductivity type semiconductor layer 124.

The second ionic strength P 2 may be less than the first ionic strength P 1 and the twelfth ionic strength P 12. The second ionic strength P 2 may be the highest in the first conductivity type semiconductor layer 124, but is not necessarily limited thereto, and the second ionic strength P 2 may be equal to or lower than the eighth ionic strength P 8 .

The second ionic strength P2 may be the ionic strength of the control layer 124e. Since the intensity of aluminum ions in the control layer 124e is high, the first carrier energy injected from the first conductivity type semiconductor layer 124 toward the active layer 126 is lowered and the first and second carriers recombine in the active layer 126. [ The density or the density of the particles can be balanced. Therefore, the light emitting efficiency can be improved and the optical output characteristic of the semiconductor device can be improved.

The fourth ionic strength P4 may be a point at which the ionic strength of aluminum is lowest in the first direction D2 from the second ionic strength P2. The first direction D2 may be a direction away from the surface E0 of the semiconductor structure 120. The fourth ionic strength (P4) may have the lowest ionic strength in the first conductivity type semiconductor layer (124).

The fourth ionic strength P4 may be the ionic strength of the third sub-semiconductor layer 124c. Accordingly, when the laser lift-off (hereinafter referred to as LLO) process is applied during the process of the semiconductor device, the active layer 126 is prevented from being damaged by the LLO process by absorbing the laser to prevent penetration of the laser into the active layer 126 .

In addition, since the fourth ionic strength P4 is sufficiently low, the resistance with respect to the first electrode is lowered, and the injection efficiency of the current injected into the semiconductor structure 120 can be improved. For this reason, the fourth ionic strength P4 may be lowest in the first direction D2 from the second ionic strength P2. However, the fourth ionic strength P4 may be equal to or higher than the tenth ionic strength P10 of the buffer layer 121, but not necessarily limited thereto.

The fifth ionic strength P5 may be disposed between the second ionic strength P2 and the fourth ionic strength P4. The fifth ionic strength P5 may be the ionic strength of the fourth sub-semiconductor layer 124d. The region corresponding to the thickness of the fourth sub semiconductor layer 124d may have the fifth ion intensity P5 uniformly. Therefore, the density of the current injected into the active layer 126 can be made uniform. The fifth ionic strength P5 may be less than the second ionic strength P2 and greater than the fourth ionic strength P4.

The seventh ionic strength P7 may be disposed apart from the fourth ionic strength P4 in the first direction D2. The seventh ionic strength P7 may be the ionic strength of the second sub semiconductor layer 124b. The region corresponding to the thickness of the second sub-semiconductor layer 124b may have the seventh ionic strength P7 uniformly.

The eighth ionic strength P8 may have a higher intensity than the seventh ionic strength P7. The eighth ionic strength P8 may be the ionic strength of the first sub-semiconductor layer 124a. The region corresponding to the thickness of the first sub-semiconductor layer 124a can have the eighth ionic intensity P8 uniformly.

The first conductivity type semiconductor layer 124 can sequentially lower the eighth ion intensity P8 and the seventh ion intensity P7 to have the fourth ion intensity P4. The crystallinity of the semiconductor structure 120 may be deteriorated if the ion intensity is sharply reduced from the eighth ionic strength P8 directly to the fourth ionic strength P4 without the seventh ionic strength P7.

The ion intensity emitted from the buffer layer 121 may have eighth to twelfth ion intensities (P8, P9, P10, P11, P12). At this time, the twelfth ionic strength P12 may be the maximum ionic strength (the first maximum intensity) in the buffer layer 121, and the tenth ionic strength P10 may be the minimum ionic strength Strength).

The eighth ionic strength P8 of the buffer layer 121 may be the same as the eighth ionic intensity P8 of the first conductivity type semiconductor layer 124. [ That is, the first conductivity type semiconductor layer 124 and the buffer layer 121 can be separated from each other at a point C1 where the first dopant has an effective value.

The ninth ionic strength (P9, first intermediate strength) may have an intensity higher than the eighth ionic strength (P8). The ninth ionic strength P9 may be the ionic strength of the fourth buffer layer 121d. Since the fourth buffer layer 121d has a relatively thin thickness, the region having the ninth ionic strength P9 may be relatively narrow. The ninth ionic strength P9 can be the highest in the region between the fourth ionic strength P4 and the tenth ionic strength P10. The ninth ionic strength P9 may be less than the first ionic strength P1 and the twelfth ionic strength P12 but may be greater than the second ionic strength P2.

The tenth ionic strength (P10) may have the smallest intensity in the buffer layer 121. The tenth ionic strength P10 may be the ionic strength of the third buffer layer 121c. The third buffer layer 121c may be a super lattice layer in which a first sublayer having a high aluminum composition and a second sublayer having a low aluminum composition are alternately stacked. However, the thicknesses of the first sub-layer and the second sub-layer are thin and can be measured to have a uniform ionic strength.

The third buffer layer 121c may have a superlattice structure to relax the stress of the semiconductor structure 120. In addition, when the LLO laser light is irradiated, the substrate 110 can be separated by absorbing the LLO laser light.

The 12th ionic strength (P12) may have the highest ionic strength in the semiconductor structure 120. The twelfth ionic strength P12 may be the ionic strength of the first buffer layer 121a. The first buffer layer 121a may be AlN. Therefore, in the case of the flip chip, the aluminum ion intensity can be detected to be the highest in the AlN buffer layer. The eleventh ionic strength P11 may be greater than the tenth ionic strength P10 and less than the twelfth ionic strength P12.

The ratio (L2) of the first ionic strength (P1) to the third ionic strength (P3) may be from 1: 0.42 to 1: 0.85. When the ratio of the third ionic strength (P3) to the first ionic strength (P1) is 1: 0.42 or more, the aluminum strength of the third ionic strength (P3) can be increased. Therefore, the problem of absorbing light in the surface layer can be solved. When the ratio is less than 1: 0.85, the strength of the third ionic strength (P3) is sufficiently low, so that the contact resistance with the second electrode can be lowered.

The ratio (L1) of the 12th ionic strength (P12) to the third ionic strength (P3) may be 1: 0.3 to 1: 0.6. When the ratio is 1: 0.3 or more, the aluminum intensity of the third ionic strength (P3) is increased and the problem of light absorption can be solved. When the ratio is less than 1: 0.6, the contact resistance with the second electrode can be lowered.

The ratio of the third ionic strength (P3) to the fourth ionic strength (P4) may be from 1: 1.1 to 1: 1.8. When the ratio of the third ionic strength (P3) to the fourth ionic strength (P4) is 1: 1.1 to 1: 1.8, sufficient ionic strength is secured while lowering the contact resistance with the first electrode, Can be reduced.

The ratio of the third ionic strength (P3) to the tenth ionic strength (P10) may be from 1: 1.2 to 1: 2. When the ratio of the third ionic strength P3 to the tenth ionic strength P10 is 1: 1.2 to 1: 2, the tenth ionic strength P10 is sufficiently increased while relaxing the stress of the semiconductor structure 120, It is possible to reduce the light absorption rate.

The ratio of the second ionic strength (P2) to the first ionic strength (P1) may be from 1: 1.1 to 1: 2. When the ratio of the second ionic strength P 2 to the first ionic strength P 1 is 1: 1.1 or more, the first ionic strength P 1 is increased to effectively block the first carrier from passing through the active layer 126. When the ratio of the second ionic strength P2 to the first ionic strength P1 is 1: 2 or less, the balance between the concentration of the first carrier injected into the active layer 126 and the luminescent recombination is balanced with the concentration of the second carrier It is possible to improve the amount of light emitted by the semiconductor element.

The ratio of the fourth ionic strength (P4) to the second ionic strength (P2) may be from 1: 1.2 to 1: 2.5. When the ratio of the fourth ionic strength P4 to the second ionic strength P2 is 1: 1.2 or more, the resistance between the fourth ionic strength P4 and the first electrode can be lowered. When the ratio of the fourth ionic strength P4 to the second ionic strength P2 is 1: 2.5 or less, the fourth ionic strength P4 increases and the absorption rate of the ultraviolet wavelength band light can be reduced.

The ratio of the fifth ionic strength (P5) to the second ionic strength (P2) may be from 1: 1.1 to 1: 2.0. In embodiments, the semiconductor structure 120 that emits deep ultraviolet light may be composed of a GaN-based material that includes a large amount of aluminum compared to the semiconductor structure 120 that emits blue light. Accordingly, the ratio of the mobility of the first carrier to the mobility of the second carrier may be different from that of the semiconductor structure 120 that emits blue light. That is, when the ratio of the fifth ionic strength P5 to the second ionic strength P2 is 1: 1.1 or more, the concentration of the first carrier injected into the active layer 126 can be secured. When the ratio of the fifth ionic strength (P5) to the second ionic strength (P2) is 1: 2.0 or less, the fifth ionic strength (P5) increases and crystallinity can be improved.

The ratio of the fourth ionic strength (P4) to the fifth ionic strength (P5) may be from 1: 1.1 to 1: 2.0. When the ratio of the fourth ionic strength (P4) to the fifth ionic strength (P5) is 1: 1.1 or more, the fifth ionic strength (P5) increases and crystallinity can be improved. In addition, when the ratio of the fourth ionic strength P4 to the fifth ionic strength P5 is 1: 2.0 or less, the fourth ionic strength P4 increases and the absorption rate of the ultraviolet wavelength band light can be reduced.

The tenth ionic strength (P10) may be 80% to 120% of the fourth ionic strength (P4). When the tenth ionic strength P10 is higher than 80% of the fourth ionic strength P4, the absorption rate of ultraviolet light can be reduced, and when the tenth ionic strength P10 is less than 120% of the fourth ionic strength P4 The ionic strength is lowered and the stress of the semiconductor structure 120 can be relaxed.

The ratio of the tenth ionic strength (P10) to the eighth ionic strength (P9) may be from 1: 1.1 to 1: 5. When the ratio of the tenth ionic strength (P10) to the eighth ionic strength (P9) is 1: 1.1 or more, the ninth ionic strength (P9) is increased and the crystallinity can be improved. In addition, when the ratio is 1: 1.5 or less, the tenth ionic strength (P10) increases and the absorption rate of ultraviolet wavelength band light can be reduced.

The ratio of the tenth ionic strength (P10) to the twelfth ionic strength (P12) may be from 1: 1.4 to 1: 2. When the ratio of the tenth ionic strength (P10) to the twelfth ionic strength (P12) is 1: 1.4 or more, the 12th ionic strength (P12) is increased and the crystallinity can be improved. In addition, when the ratio is 1: 2 or less, the tenth ionic strength (P10) increases and the absorption rate of ultraviolet wavelength band light can be reduced.

Referring to FIGS. 3 and 5, the doping concentration of the first dopant (e.g., Si) may have a first doping concentration S1 in the first conductive semiconductor layer 124. At this time, the first conductivity type semiconductor layer 124 may have a doping concentration S2 lower than the first doping concentration S1 in a certain region. However, the present invention is not limited thereto, and the doping concentration of the first conductivity type semiconductor layer 124 may be uniform over the entire region.

The second doping concentration S4 may be a doping concentration of the barrier layer 126b of the active layer 126 and / or the fourth sub-semiconductor layer 124d. Therefore, 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. In addition, 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 a doping concentration at 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, in the semiconductor structure 120 according to the embodiment, it can be seen that the surface layer on which the second electrode is disposed contains aluminum and the first dopant.

The fourth doping concentration S3 may be disposed between the first conductivity type 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 the 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 the second dopant. The fourth doping concentration S3 and the fifth doping concentration S5 may be less than the first through third doping concentrations S1, S4, and S6.

Referring to FIG. 5, the doping concentration of the second dopant (for example, Mg) is the highest at the surface E0, and may gradually decrease as the distance from the surface increases. The doping concentration M1 of the second dopant (e.g., Mg) at the surface E0 of the semiconductor structure 120 is higher than the doping concentration S6 of the first dopant (e.g., Si). This may be because the doping concentration of the second dopant is increased by the memory effect even though the second dopant is not doped at the surface of the semiconductor structure 120.

The doping concentration of the second dopant increases as the surface of the second dopant approaches the surface, but may include a period (interval between M2 and M3) in which the doping concentration decreases as the surface of the second dopant becomes closer to the surface. According to this reverse period, the concentration of the second dopant is reduced and the resistance is increased, so that the hole dispersion efficiency can be improved.

The second dopant may be present in all regions of the second conductive type semiconductor layer 127 and in a portion of the active layer 126, but the present invention is not limited thereto. The second dopant may be disposed only in the second conductive semiconductor layer 127, but may diffuse to the active layer 126. Therefore, the injection efficiency of the second dopant injected into the active layer 126 can be improved. However, when the second dopant is diffused to the first conductivity type semiconductor layer 124, the leakage current of the semiconductor element and / or the non-emission recombination of the first and second carriers may occur and the reliability and / .

Fig. 6 is a first modification of Fig. 3, and Fig. 7 is a second modification of Fig.

Referring to FIG. 6, the semiconductor structure 120 can only be measured up to the tenth ionic strength P10. This structure can be observed in a structure in which the substrate 110 is separated by the third buffer layer 121c absorbing and separating the LLO light like a vertical structure.

In addition, in the process of forming irregularities on the surface, the layer having the eighth ionic strength (P8) and the layer having the ninth ionic strength (P9) can be partially removed.

Referring to FIG. 7, the third buffer layer 121c having the tenth ionic strength P10 may be omitted. If the LLO isolation layer is not required or the superlattice structure for relieving stress is omitted because the substrate 110 is not removed by way of example, a spectrum as shown in FIG. 7 can be observed. In this case, the ionic strength in the buffer layer may have the lowest eighth ionic strength (P8).

8 is a conceptual diagram of a semiconductor device according to the first embodiment of the present invention.

8, a semiconductor device according to an embodiment includes a semiconductor structure 120 including a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, and an active layer 126, A first electrode pad 141 electrically connected to the first conductive semiconductor layer 124 and a second electrode pad 142 electrically connected to the second conductive semiconductor layer 127.

The substrate 110 may be formed of a material selected from the group consisting of sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge.

The semiconductor structure 120 includes a recess 128 disposed through a portion of the first conductivity type semiconductor layer 124 through the second conductivity type semiconductor layer 127 and the active layer 126. An insulating layer 131 may be formed on the sides of the semiconductor structure 120 and on the recesses 128. At this time, the insulating layer 131 may expose a part of the second conductivity type semiconductor layer 127.

Insulating layer 131 is _{SiO 2, SixOy, Si 3 N} 4, SixNy, SiOxNy, Al 2 O 3, TiO 2, but may be at least one is selected from the group consisting of forming AlN or the like, not limited to this. The insulating layer 131 may be a DBR (distributed Bragg reflector) having a multi-layer structure including silver oxide or Ti compound. However, the insulating layer 131 may include various reflective structures without being limited thereto.

When the insulating layer 131 performs a reflection function, light emitted toward the side surface of the active layer 126 may be reflected upward to improve light extraction efficiency. In this case, as the number of recesses increases, the light extraction efficiency may be more effective.

The first electrode pad 141 may be electrically connected to the first conductive semiconductor layer 124. Specifically, the first electrode pad 141 may be electrically connected to the first conductive semiconductor layer 124 through the recess 128. Although not shown, a first electrode may be disposed between the first electrode pad 141 and the first conductive semiconductor layer 124.

The second electrode pad 142 may be electrically connected to the second conductive semiconductor layer 127. Specifically, the second electrode pad 142 may be electrically connected to the electrode layer 143 through the insulating layer 131. The electrode layer 143 may be a second electrode.

9 is a conceptual view of a semiconductor device according to a second embodiment of the present invention.

The semiconductor device according to Fig. 9 may have the structure of a general horizontal type semiconductor device. That is, a second electrode pad is disposed on the second conductivity type semiconductor layer 127 of the semiconductor structure 120, and a first electrode pad may be disposed on the first conductivity type semiconductor layer 124 exposed by the mesa etching. have. Such a horizontal semiconductor device can be mounted on the circuit board 1 by solder.

10 is a conceptual view of a semiconductor device according to a third embodiment of the present invention.

10, a semiconductor device according to an embodiment includes a semiconductor structure 120 including a first conductive semiconductor layer 124, a second conductive semiconductor layer 127, and an active layer 126, And a second electrode 146 electrically connected to the second conductivity type semiconductor layer 127. The first electrode 142 is electrically connected to the first conductivity type semiconductor layer 124 and the second electrode 146 is electrically connected to the second conductivity type semiconductor layer 127. [

The first conductive semiconductor layer 124, the active layer 126, and the second conductive semiconductor layer 127 may be disposed in a first direction (Y direction). Hereinafter, a first direction (Y direction), which is the thickness direction of each layer, is defined as a vertical direction, and a second direction (X direction) perpendicular to the first direction (Y direction) is defined as a horizontal direction.

The semiconductor structure 120 according to the embodiment can be applied to all the structures described above. The semiconductor structure 120 may include a plurality of recesses 128 disposed through a portion of the first conductivity type semiconductor layer 124 through the second conductivity type semiconductor layer 127 and the active layer 126 .

The first electrode 142 may be disposed on the upper surface of the recess 128 and may be electrically connected to the first conductive semiconductor layer 124. The second electrode 146 may be disposed under the second conductive semiconductor layer 127.

The first electrode 142 and the second electrode 146 may be ohmic electrodes. The first electrode 142 and the second electrode 146 may be formed of one selected from the group consisting of ITO (indium tin oxide), IZO (indium zinc oxide), IZTO (indium zinc tin oxide), IAZO (indium aluminum zinc oxide), IGZO ), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO ZnO, ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au or Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ru, Mg, Zn, Pt, Au, and Hf. However, the present invention is not limited to these materials. Illustratively, the first electrode may have a plurality of metal layers (e.g. Cr / Al / Ni) and the second electrode may be ITO.

The second conductive layer 150 may electrically connect the second electrode 146 and the second electrode pad 166.

The second electrode 146 may be disposed directly on the second conductive semiconductor layer 127. When the second conductivity type semiconductor layer 127 is AlGaN, hole injection may not be smooth due to low electric conductivity. Therefore, it is necessary to appropriately adjust the Al composition of the second conductivity type semiconductor layer 127. This will be described later.

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

The first conductive layer 165 and the bonding layer 160 may be disposed along the bottom surface of the semiconductor structure 120 and the shape of the recess 128. [ The first conductive layer 165 may be made of a material having a high reflectivity. Illustratively, the first conductive layer 165 may comprise aluminum. When the electrode layer 165 includes aluminum, it functions to reflect light emitted from the active layer 126 toward the substrate 170 in an upper direction, thereby improving light extraction efficiency. However, the present invention is not limited thereto, and the first conductive layer 165 may provide a function of being electrically connected to the first electrode 142. The first conductive layer 165 may be disposed without containing a highly reflective material, such as aluminum and / or silver (Ag), in which case the first electrode 142 A reflective metal layer (not shown) may be disposed between the first conductive layer 165 and the second conductive type semiconductor layer 127 and between the first conductive layer 165 and the first conductive layer 165, .

The bonding layer 160 may include a conductive material. Illustratively, the bonding layer 160 may comprise a material selected from the group consisting of gold, tin, indium, aluminum, silicon, silver, nickel, and copper, or alloys thereof.

The substrate 170 may be made of a conductive material. Illustratively, substrate 170 may comprise a metal or semiconductor material. The substrate 170 may be a metal having excellent electrical conductivity and / or thermal conductivity. In this case, the heat generated during semiconductor device operation can be quickly dissipated to the outside. When the substrate 170 is formed of a conductive material, the first electrode 142 may be supplied with current from the outside through the substrate 170.

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

A passivation layer 180 may be disposed on the top and sides of the semiconductor structure 120. The thickness of the passivation layer 180 may be greater than or equal to 200 nm and less than or equal to 500 nm. When the thickness is not more 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 reduced. Or the process time of the semiconductor device is increased, the problem that the unit price of the semiconductor device is increased can be solved.

Unevenness may be formed on the upper surface of the semiconductor structure 120. Such unevenness can improve the extraction efficiency of light emitted from the semiconductor structure 120. The average height of the unevenness may be different depending on the wavelength of ultraviolet light. In the case of UV-C, the height of the unevenness is about 300 nm to 800 nm and the light extraction efficiency can be improved when the average height is 500 nm to 600 nm.

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

11, the semiconductor device package comprises a body 2 formed with a groove 3, a semiconductor element 1 disposed on the body 2, and a semiconductor element 1 disposed on the body 2 and electrically connected to the semiconductor element 1 And may include a pair of lead frames 5a and 5b connected thereto. The semiconductor element 1 may include all of the structures described above.

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

The groove 3 may be formed so as to be wider as it is away from the semiconductor element, and a step 3a may be formed on the inclined surface.

The light-transmitting layer 4 may cover the groove 3. [ The light-transmitting layer 4 may be made of a glass material, but is not limited thereto. The light-transmitting layer 4 is not particularly limited as long as it is a material capable of effectively transmitting ultraviolet light. The inside of the groove 3 may be an empty space.

Semiconductor devices can be applied to various types of light source devices. Illustratively, the light source device may be a concept including a sterilizing device, a curing device, a lighting device, and a display device and a vehicle lamp. That is, semiconductor devices can be applied to various electronic devices arranged in a case to provide light.

The sterilizing device may include a semiconductor device according to an embodiment to sterilize a desired area. The sterilization device can be applied to home appliances such as water purifier, air conditioner, refrigerator, but is not limited thereto. That is, the sterilization apparatus can be applied to various products requiring sterilization (for example, medical apparatus).

Illustratively, the water purifier may be equipped with a sterilizing device according to an embodiment to sterilize circulating water. The sterilizing apparatus may be disposed in a nozzle or a discharge port through which water circulates and irradiate ultraviolet rays. At this time, the sterilizing device may include a waterproof structure.

The curing device may include a semiconductor device according to the embodiment to cure various kinds of liquids. Liquids can be the broadest concept that encompasses a variety of materials that cure upon exposure to ultraviolet radiation. Illustratively, the curing device can cure various types of resins. Or the curing device may be applied to cure a cosmetic product such as manicure.

The illumination device may include a light source module including a substrate and semiconductor elements of the embodiment, a heat dissipation unit that dissipates heat of 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. Further, the lighting device may include a lamp, a head lamp, or a street lamp or the like.

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, the reflector, the light emitting module, the light guide plate, and the optical sheet can 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 reflection plate to guide the light emitted from the light emitting module forward, and the optical sheet may include a prism sheet or the like and be disposed in front of the light guide plate. The display panel is disposed in front of the optical sheet, and the image signal output circuit supplies an image signal to the display panel, and the color filter can be disposed in front of the display panel.

The semiconductor device can be used as a backlight unit of an edge type when used as a backlight unit of a display device or as a backlight unit of a direct-bottom type.

The semiconductor device may be a laser diode other than the light emitting diode described above.

The laser diode may include the first conductivity type semiconductor layer, the active layer and the second conductivity type semiconductor layer having the above-described structure, like the light emitting element. Then, electro-luminescence (electroluminescence) phenomenon in which light is emitted when an electric current is applied after bonding the p-type first conductivity type semiconductor and the n-type second conductivity type semiconductor is used, And phase. That is, the laser diode can emit light having one specific wavelength (monochromatic beam) with the same phase and in the same direction by using a phenomenon called stimulated emission and a constructive interference phenomenon. It can be used for optical communication, medical equipment and semiconductor processing equipment.

As the light receiving element, a photodetector, which is a kind of transducer that detects light and converts the intensity of the light into an electric signal, is exemplified. As photodetectors, photodetectors (silicon, selenium), photodetectors (cadmium sulfide, cadmium selenide), photodiodes (for example, visible blind spectral regions or PDs with peak wavelengths in the true blind spectral region) A transistor, a photomultiplier tube, a phototube (vacuum, gas-filled), and an IR (Infra-Red) detector, but the embodiment is not limited thereto.

In addition, a semiconductor device such as a photodetector may be fabricated using a direct bandgap semiconductor, which is generally excellent in photo-conversion efficiency. Alternatively, the photodetector has a variety of structures, and the most general structure includes a pinned photodetector using a pn junction, a Schottky photodetector using a Schottky junction, and a metal-semiconductor metal (MSM) photodetector have.

The photodiode, like the light emitting device, may include the first conductivity type semiconductor layer having the structure described above, the active layer, and the second conductivity type semiconductor layer, and may have a pn junction or a pin structure. The photodiode operates by applying reverse bias or zero bias. When light is incident on the photodiode, electrons and holes are generated and a current flows. At this time, the magnitude of the current may be approximately proportional to the intensity of the light incident on the photodiode.

A photovoltaic cell or a solar cell is a type of photodiode that can convert light into current. The solar cell, like the light emitting device, may include the first conductivity type semiconductor layer, the active layer and the second conductivity type semiconductor layer having the above-described structure.

In addition, it can be used as a rectifier of an electronic circuit through a rectifying characteristic of a general diode using a p-n junction, and can be applied to an oscillation circuit or the like by being applied to a microwave circuit.

In addition, the above-described semiconductor element is not necessarily implemented as a semiconductor, and may further include a metal material as the case may be. For example, a semiconductor device such as a light receiving element may be implemented using at least one of Ag, Al, Au, In, Ga, N, Zn, Se, P, or As, Or may be implemented using a doped semiconductor material or an intrinsic semiconductor material.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (13)

A semiconductor structure including a buffer layer comprising aluminum, a first conductive semiconductor layer comprising aluminum, an active layer comprising aluminum, and a second conductive semiconductor layer comprising aluminum,
Wherein the semiconductor structure emits secondary ions containing aluminum ions upon primary ion irradiation,
Wherein the aluminum ion intensity emitted from the buffer layer has a first maximum intensity and a first minimum intensity,
The aluminum ion intensity emitted from the first conductivity type semiconductor layer has a second maximum intensity and a second minimum intensity,
The aluminum ion intensity emitted from the second conductivity type semiconductor layer has a third maximum intensity and a third minimum intensity,
Wherein said first maximum intensity is highest in aluminum ion intensity in said semiconductor structure,
Wherein the third minimum strength is the minimum aluminum ion intensity in the semiconductor structure,
Wherein the ratio of the first maximum intensity to the third minimum intensity is 1: 0.3 to 1: 0.6.
The method according to claim 1,
And the third maximum strength is higher than the second maximum strength, the second minimum strength, and the first minimum strength.
3. The method of claim 2,
The second maximum intensity is higher than the first minimum intensity,
Wherein the first minimum strength is higher than the second minimum strength.
The method according to claim 1,
Wherein the aluminum ion intensity emitted from the buffer layer has a first intermediate intensity with the highest intensity between the first minimum intensity and the second minimum intensity.
5. The method of claim 4,
Wherein the first intermediate strength is higher than the second maximum strength.
6. The method of claim 5,
Wherein the first intermediate strength is smaller than the first maximum strength.
The method according to claim 1,
Wherein the aluminum ion intensity emitted from the active layer comprises a plurality of peaks and a plurality of valleys,
Wherein the plurality of peaks are smaller than the first maximum intensity, the second maximum intensity, and the third maximum intensity.
The method according to claim 1,
Wherein the second conductivity type semiconductor layer includes a blocking layer, a P-type conductivity type semiconductor layer, and a surface layer.
9. The method of claim 8,
Wherein the surface layer comprises a first dopant and a second dopant.
The method according to claim 1,
Wherein the secondary ion comprises a first dopant ion and a second dopant ion.
11. The method of claim 10,
The first dopant ion concentration is
A first doping concentration that is emitted from the first conductivity type semiconductor layer,
A second doping concentration emitted from the active layer, and
And a third doping concentration emitted from the second conductivity type semiconductor layer.
12. The method of claim 11,
Wherein the third doping concentration is higher than the first doping concentration and the second doping concentration.
12. The method of claim 11,
A fourth doping concentration disposed between the first doping concentration and the second doping concentration, and
And a fifth doping concentration disposed between the second doping concentration and the third doping concentration,
Wherein the fourth doping concentration and the fifth doping concentration are smaller than the first through third doping concentrations.

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