Surface emitting laser device and light emitting device including the same

Abstract

The present invention relates to a surface emitting laser device and a light emitting device including the same. The surface emitting laser device includes: a first reflective layer, the first reflective layer includes a first conductive dopant; a second reflective layer, the second reflective layer includes a second conductive dopant; and an active region, the active region is arranged between the first reflective layer and the second reflective layer, the active region includes a first cavity including the first conductive dopant layer, the first cavity is adjacent to the first reflective layer, and the first cavity includes an Al-based x GaAs layer, 0

Description

[0001] This application is a divisional application of the invention patent application with application number 201910011551.0 filed on January 7, 2019, and invention name: “Surface emitting laser device and light-emitting device including the same”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to KR10-2018-0002976 filed in Korea on January 9, 2018, and KR10-2018-0013486 filed in Korea on February 2, 2018, which are hereby incorporated by reference in their entirety. Technical Field

[0004] Embodiments relate to a semiconductor device, and more particularly, to a surface emitting laser device, a surface emitting laser package, and a light emitting device including the surface emitting laser device. Background Art

[0005] Semiconductor devices including compounds such as GaN and AlGaN have many advantages such as having a wide and easily adjustable bandgap energy, and can be variously used as light emitting devices, light receiving devices, and various diodes.

[0006] In particular, light-emitting devices using compound semiconductor materials from the III-V or II-VI groups of semiconductors, such as light-emitting diodes or laser diodes, can achieve various colors such as red, green, blue, and ultraviolet through the development of thin film growth technology and device materials. They can also achieve highly efficient white light rays by using fluorescent materials or combining colors. Compared to traditional light sources such as fluorescent lamps and incandescent lamps, they have the advantages of low power consumption, semi-permanent lifespan, fast response speed, safety, and environmental friendliness. Furthermore, when light-receiving devices such as photodetectors or solar cells are manufactured using compound semiconductor materials from the III-V or II-VI groups through the development of device materials, light in various wavelength regions, from gamma rays to radio wavelengths, can be utilized by absorbing light in various wavelength regions and generating photocurrent. Furthermore, light-emitting devices have the advantages of fast response speed, safety, environmental friendliness, and easy control of device materials, making them easily applicable to power control or microwave circuits or communication modules.

[0007] As a result, applications have expanded to transmitting modules of optical communication devices, LED backlights that replace cold cathode fluorescent lamps (CCFLs) that constitute the backlights of liquid crystal display (LCD) devices, white LED lighting devices that can replace fluorescent lamps or incandescent lamps, car headlights, traffic lights, and even sensors that sense gas or fire.

[0008] Furthermore, the application can be extended to high-frequency application circuits or other power control devices, and even communication modules.

[0009] For example, in conventional semiconductor light source device technology, there is a vertical cavity surface emitting laser (VCSEL), which is used for optical communication, optical parallel processing, optical connection, and the like.

[0010] Meanwhile, in the case of a laser diode used in such a communication module, it is designed to operate at a low current.

[0011] However, when such a VCSEL is applied to laser diode autofocus (LDAF) or a structured optical sensor, it is operated at a high current of several kW, resulting in problems of reduced light output and increased threshold current.

[0012] That is, in the epitaxial structure of conventional VCSELs, response speed is important in conventional structures focused on data optical communications, but when developing high-power packages for sensors, light output and voltage efficiency are important characteristics. However, there are limitations in simultaneously improving light output and voltage efficiency in conventional VCSEL structures.

[0013] For example, the VCSEL structure requires a large number of reflective layers, such as a distributed Bragg reflector (DBR), but series resistance occurs in such a DBR.

[0014] In the prior art, attempts have been made to improve voltage efficiency by reducing resistance by increasing doping concentration to prevent this resistance from occurring in such DBRs. However, when the doping concentration is increased, there is a technical contradiction in which internal light absorption occurs due to the dopant and light output decreases.

[0015] In addition, the DBR as the reflective layer in the prior art is formed by alternately arranging Al2O3 layers with different Al compositions. x GaAs-based materials are used to increase reflectivity. However, an electric field is generated by band bending at the interface between adjacent DBR layers, and this electric field becomes a carrier barrier, thereby reducing light output.

[0016] In addition, when developing a high-power package for a VCSEL, light output and voltage efficiency are important characteristics, but there is a limit to improving both light output and voltage efficiency simultaneously.

[0017] For example, the related art VCSEL structure has a light emitting layer and a predetermined resonator (cavity) region, and such a region has a high internal resistance, which leads to technical problems in that a driving voltage is increased and voltage efficiency is reduced.

[0018] Additionally, in order to improve light output in the prior art, optical confinement is required around the light emitting layer, but there is no adequate solution in the prior art. Summary of the Invention

[0019] One of the technical problems of the embodiment is to provide a surface emitting laser device and a light emitting device including the same, which are capable of improving light output while improving voltage efficiency.

[0020] Furthermore, one of the technical issues of the embodiment is to provide a surface emitting laser device and a light emitting device including the same, which can improve light output by minimizing the influence of a carrier barrier due to generation of an electric field in a reflective layer.

[0021] Furthermore, one of the technical issues of the embodiment is to provide a surface emitting laser device and a light emitting device including the surface emitting laser device, which are capable of improving light output by improving voltage efficiency.

[0022] In addition, one of the technical issues of the embodiment is to provide a surface emitting laser device and a light emitting device including the surface emitting laser device, which are capable of improving light output by improving optical confinement efficiency around a light emitting layer.

[0023] The surface emitting laser device according to the embodiment includes: a first reflective layer 220 and a second reflective layer 250; an active region 230 arranged between the first reflective layer 220 and the second reflective layer 250, wherein the first reflective layer 220 includes a first group of first reflective layers 221 and a second group of first reflective layers 222, and the second reflective layer 250 includes a first group of second reflective layers 251 and a second group of second reflective layers 252.

[0024] In addition, the first group of second reflective layers includes: a first-first layer having a first aluminum concentration; a first-second layer having a second aluminum concentration higher than the first aluminum concentration and arranged on the first-first layer; and a first-fourth layer having a fourth aluminum concentration varying from the second aluminum concentration to the first aluminum concentration and arranged on the first-second layer.

[0025] In addition, the first-second layer can be arranged between the first-first layer and the first-fourth layer.

[0026] Additionally, the first-first layer can be closer to the aperture region than the first-second layer.

[0027] Furthermore, the second reflective layer can be doped with a second conductive dopant.

[0028] Furthermore, the second conductive doping concentration of the first-fourth layer can be higher than the second conductive doping concentration of the first-first layer and / or the first-second layer.

[0029] In addition, the second conductive dopant includes carbon (C), and the first-first layer can be closer to the aperture region than the first-second layer.

[0030] Additionally, the second reflective layer can include a third group of second reflective layers that is arranged closer to the aperture region than the first group of second reflective layers.

[0031] In addition, the average second conductive doping concentration of the third group of second reflective layers can be less than the average second conductive doping concentration of the first group of second reflective layers.

[0032] The first group of second reflective layers 251 may include: a second-first reflective layer 251p having a first aluminum concentration; a second-second reflective layer 251q having a second aluminum concentration higher than the first aluminum concentration and arranged on one side of the second-first reflective layer 251p; and a second-third reflective layer 251r having a third aluminum concentration varying from the first aluminum concentration to the second aluminum concentration and arranged between the second-first reflective layer 251p and the second-second reflective layer 251q.

[0033] The second conductive doping concentration of the second-third reflective layer 251r may be higher than the second conductive doping concentration of the second-first reflective layer 251p or the second-second reflective layer 251q.

[0034] In addition, the first group of second reflection layers 251 may include: a second-first reflection layer 251p, which has a first refractive index; a second-second reflection layer 251q, which has a second refractive index lower than the first refractive index and is arranged on one side of the second-first reflection layer 251p; and a second-third reflection layer 251r, which has a third refractive index between the first refractive index and the second refractive index and is arranged between the second-first reflection layer 251p and the second-second reflection layer 251q.

[0035] The second conductive doping concentration of the second-third reflective layer 251r may be higher than the second conductive doping concentration of the second-first reflective layer 251p or the second-second reflective layer 251q.

[0036] A surface-emitting laser device according to an embodiment includes: a first reflective layer 220 and a second reflective layer 250; an active region 230 arranged between the first reflective layer 220 and the second reflective layer 250, wherein the first reflective layer 220 includes: a first-first layer 220a having a first aluminum concentration; a first-second layer 220b having a second aluminum concentration higher than the first aluminum concentration and arranged on one side of the first-first layer 220a; and a first-third layer 220c having a third aluminum concentration varying from the first aluminum concentration to the second aluminum concentration and arranged between the first-first layer 220a and the first-second layer 220b.

[0037] The first reflective layer 220 may include a first conductive dopant, and a first conductive dopant concentration of the first-third layer 220 c may be lower than that of the first-first layer 220 a and the first-second layer 220 b .

[0038] In addition, the surface-emitting laser device according to the embodiment includes: a first reflective layer 220 and a second reflective layer 250; and an active region 230, which is arranged between the first reflective layer 220 and the second reflective layer 250, wherein the first reflective layer 220 includes: a first-first layer 220a having a first refractive index; a first-second layer 220b having a second refractive index lower than the first refractive index and arranged on one side of the first-first layer 220a; and a first-third layer 220c having a third refractive index between the first refractive index and the second refractive index and arranged between the first-first layer 220a and the first-second layer 220b.

[0039] The first reflective layer 220 may include a first conductive dopant, and a first conductive dopant concentration of the first-third layer 220 c may be lower than that of the first-first layer 220 a and the first-second layer 220 b .

[0040] According to the embodiment, there is provided a surface emitting laser device capable of improving light output while improving voltage efficiency and a light emitting device including the surface emitting laser device.

[0041] Furthermore, the embodiment has the advantages of being able to provide a surface emitting laser device capable of improving light output by minimizing the influence of a carrier barrier due to generation of an electric field in a reflective layer and a light emitting device including the surface emitting laser device.

[0042] The surface emitting laser device according to the embodiment may include a first reflective layer 220 including a first conductive dopant, a second reflective layer 250 including a second conductive dopant, and an active region 230 disposed between the first reflective layer 220 and the second reflective layer 250 .

[0043] The active region 230 may include a first cavity 231 and an active layer 232, the first cavity 231 being arranged on the first reflective layer 220, the active layer 232 including a quantum well 232a and a quantum wall 232b and being arranged on the first cavity 231, and the first cavity 231 may be adjacent to the first reflective layer 220 and may include a first conductive first doped layer 261.

[0044] The thickness of the first conductive-first doping layer 261 may be 70% or less of the thickness of the first cavity 231 .

[0045] A surface emitting laser package according to an embodiment may include a surface emitting laser device.

[0046] According to the embodiment, it is possible to provide a surface emitting laser device and a light emitting device including the same, which have a technical effect of being able to improve light output by improving voltage efficiency.

[0047] Furthermore, according to the embodiment, a surface emitting laser device and a light emitting device including the same can be provided, which have a technical effect of being able to improve light output by improving optical confinement efficiency around a light emitting layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 is a cross-sectional view of a surface emitting laser device according to an embodiment.

[0049] Figure 2 is an enlarged cross-sectional view of a surface emitting laser device according to an embodiment.

[0050] Figure 3 is first distribution data of the refractive index and light energy in the surface emitting laser device according to the embodiment.

[0051] Figure 4A is first data of the refractive index and light energy in the first reflective layer of the surface emitting laser device according to the embodiment.

[0052] Figure 4B 1 and 2 are data on the Al concentration and the doping concentrations of dopants Si and C in the surface emitting laser device according to the embodiment.

[0053] Figure 4C is second distribution data of the refractive index in the surface emitting laser device according to the embodiment.

[0054] Figure 4D is second data on the refractive index in the first reflective layer of the surface emitting laser device according to the embodiment.

[0055] Figure 4E is data on the refractive index in the second reflective layer of the surface-emitting laser device according to the embodiment.

[0056] Figure 4F 1 is secondary ion mass spectrometry (SIMS) data of the second reflective layer of the surface emitting laser device according to the embodiment.

[0057] Figure 4G yes Figure 4F Magnified view of the P2 region.

[0058] Figures 5 to 8is a cross-sectional view of a process of manufacturing a surface emitting laser device according to an embodiment.

[0059] Figures 9 to 14 is a cross-sectional view of a process of manufacturing a surface-emitting laser device according to the second embodiment.

[0060] Figure 15 is an exemplary view of an energy band diagram of the semiconductor device according to the third embodiment.

[0061] Figure 16 is an exemplary view of an energy band diagram of a semiconductor device according to a fourth embodiment.

[0062] Figure 17A and 17B is doping concentration data in the cavity region of the semiconductor device according to the embodiment.

[0063] Figure 18 is an exemplary view of an energy band diagram of a semiconductor device according to a fifth embodiment.

[0064] Figure 19 is a perspective view of a mobile terminal including a surface emitting laser package according to an embodiment. DETAILED DESCRIPTION

[0065] Hereinafter, a light emitting device, a light emitting device package, and a lighting system according to embodiments will be described with reference to the accompanying drawings.

[0066] In the description of the embodiments, it will be understood that when a layer (or film) is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Furthermore, it will be understood that when a layer is referred to as being "under" another layer, it can be directly under the other layer, and one or more intervening layers may also be present. Furthermore, it will be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.

[0067] In an embodiment, the semiconductor device may include various electronic devices such as a light emitting device and a light receiving device, and the light emitting device and the light receiving device may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer. In an embodiment, the semiconductor device may be a laser diode. For example, in an embodiment, the semiconductor device may be a vertical cavity surface emitting laser (VCSEL), but is not limited thereto.

[0068] (Example)

[0069] Figure 1 is a cross-sectional view of a surface emitting laser device 200 according to an embodiment.

[0070] The surface emitting laser device 200 according to the embodiment may include at least one of a first electrode 215, a first substrate 210, a first reflective layer 220, an active region 230, an aperture region 240, a second reflective layer 250, a second contact electrode 255, a second electrode 280, and a passivation layer 270. The aperture region 240 may include an insulating region 242 and an aperture 241 and may be referred to as an intermediate layer. The first reflective layer 220, the active region 230, the insulating region 242, and the second reflective layer 250 may be referred to as a light emitting structure. Figure 2 As shown in , the active region 230 may include an active layer 232 and cavities 231 and 233 , and may be referred to as a cavity region.

[0071] In the following, we will mainly refer to Figure 1 The technical features of the surface emitting laser device 200 according to the embodiment will be described, and reference will also be made to Figures 2 to 4E Describe the main technical effects.

[0072] <First Substrate, First Electrode>

[0073] In an embodiment, the first substrate 210 may be a conductive substrate or a non-conductive substrate. When a conductive substrate is used, a metal having excellent electrical conductivity may be used, and since heat generated when operating the surface-emitting laser device 200 should be sufficiently dissipated, a GaAs substrate or a metal substrate having high thermal conductivity, or a silicon (Si) substrate, etc. may be used.

[0074] When a non-conductive substrate is used, an AlN substrate, a sapphire (Al 2 O 3 ) substrate, or a ceramic-based substrate can be used.

[0075] In an embodiment, the first electrode 215 may be disposed under the first substrate 210, and the first electrode 215 may be disposed as a conductive material in a single layer or multiple layers. For example, the first electrode 215 may be a metal and may include at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au), and may be formed in a single layer or multilayer structure to improve electrical characteristics and light output.

[0076] <First Reflective Layer>

[0077] Figure 2 yes Figure 1 An enlarged cross-sectional view of a region A of a surface emitting laser device according to an embodiment is shown in FIG.

[0078] In the following, reference will be made to Figure 2 Describing a surface emitting laser device of an embodiment

[0079] In an embodiment, the first reflective layer 220 may be disposed on the first substrate 210 .

[0080] The first reflective layer 220 may be doped with a first conductivity type. For example, the first conductive dopant may include an n-type dopant such as Si, Ge, Sn, Se, and Te.

[0081] In addition, the first reflective layer 220 may include a gallium-based compound, for example, AlGaAs, but not limited thereto. The first reflective layer 220 may be a distributed Bragg reflector (DBR). For example, the first reflective layer 220 may have a structure in which a first layer and a second layer made of materials having different refractive indices are alternately stacked at least once.

[0082] First, the first reflective layer 220 may include a first group of first reflective layers 221 disposed on one side of the active region 230 and a second group of first reflective layers 222 disposed more adjacent to the active region 230 than the first group of first reflective layers 221.

[0083] The first group of first reflective layers 221 and the second group of first reflective layers 222 may have a plurality of layers made of a semiconductor material having a composition formula of Al x Ga (1-x) As (0 < x < 1). As the Al in each layer increases, the refractive index of each layer may decrease, and as the Ga increases, the refractive index of each layer may increase.

[0084] In addition, the thickness of each layer may be λ / 4n, where λ may be the wavelength of the light generated in the active region 230, and n may be the refractive index of each layer with respect to the light of the above wavelength. Here, λ may be from 650 to 980 nanometers (nm), and n may be the refractive index of each layer. The first reflective layer 220 having such a structure may have a reflectivity of 99.999% with respect to light in a wavelength region of about 940 nm.

[0085] The thickness of each layer in the first reflective layer 220 may be determined according to each refractive index and wavelength λ of the light emitted in the active region 230.

[0086] For example, the first group of first reflective layers 221 may include about 30 to 40 pairs of first group of first - first layers 221a and first group of first - second layers 221b. The first group of first - first layers 221a may be formed thicker than the first group of first - second layers 221b. For example, the first group of first - first layers 221a may be formed to have a thickness of about 40 to 60 nm, and the first group of first - second layers 221b may be formed to have a thickness of about 20 to 30 nm.

[0087] In addition, the second group of first reflective layers 222 may include approximately 5 to 15 pairs of second group first-first layers 222a and second group first-second layers 222b. The second group first-first layers 222a may be formed thicker than the second group first-second layers 222b. For example, the second group first-first layers 222a may be formed to a thickness of approximately 40 to 60 nm, and the second group first-second layers 222b may be formed to a thickness of approximately 20 to 30 nm.

[0088] In the following, reference will be made to Figures 3 to 4D Technical effects of the surface emitting laser device according to the embodiment are described in detail.

[0089] First, one of the technical problems of the embodiment is to provide a surface emitting laser device and a light emitting device including the same, which can improve light output by minimizing the influence of a carrier barrier due to generation of an electric field in a reflective layer.

[0090] That is, as described above, in the conventional VCSEL structure, there is a problem in that an electric field is generated due to band bending at the interface between adjacent DBR layers, thereby generating a carrier barrier and degrading light output.

[0091] Figure 3 is first distribution data of the refractive index and light energy in the surface emitting laser device according to the embodiment, and Figure 4A yes Figure 3 2. The first data of the refractive index n and the light energy E in the first reflective layer of the region B of the surface emitting laser device according to the embodiment is shown in FIG. According to the embodiment, the distribution of the light energy emitted from the surface emitting laser device may have a maximum value centered at the active region 230, as shown in FIG. Figure 3 As shown in , and as the distance from the active region 230 becomes farther, it can be reduced in a predetermined period. Meanwhile, in the embodiment, the light energy distribution E is not limited to Figure 3 The distribution data shown in , and depending on the composition, thickness, etc. of each layer, the light energy distribution in each layer can be Figure 3 The difference shown in .

[0092] refer to Figure 3 , the surface emitting laser device 200 according to the embodiment may include a first reflective layer 220, a second reflective layer 250, and an active region 230 disposed between the first reflective layer 220 and the second reflective layer 250. In this regard, depending on the materials of the first reflective layer 220, the second reflective layer 250, and the active region 230, the surface emitting laser device 200 according to the embodiment may have the following characteristics: Figure 3 The refractive index n shown in .

[0093] refer to Figure 4A, in an embodiment, the first reflective layer 220 may include a first-first layer 220a having a first refractive index, a first-second layer 220b having a second refractive index lower than the first refractive index and disposed on one side of the first-first layer 220a, and a first-third layer 220c having a third refractive index between the first refractive index and the second refractive index and disposed between the first-first layer 220a and the first-second layer 220b.

[0094] For example, the first reflective layer 220 may have a first-first layer 220a having a first aluminum concentration, a first-second layer 220b having a second aluminum concentration higher than the first aluminum concentration and disposed on one side of the first-first layer 220a, and a first-third layer 220c having a third aluminum concentration varying from the first aluminum concentration to the second aluminum concentration and disposed between the first-first layer 220a and the first-second layer 220b.

[0095] For example, when the first reflective layer 220 includes Al x Ga (1-x) As (0 < x < 1), the first-first layer 220a may be Al 0.12 Ga 0.88 As, and when the first-second layer 220b is Al 0.88 Ga 0.12 As, then the first-third layer 220c may be Al x3 Ga (1-x3) As (0.12 ≤ x3 ≤ 0.88).

[0096] In this way, according to the embodiment, since the first reflective layer 220 is provided with the first to third layers 220c having an aluminum concentration in the intermediate region between the first-second layer 220b and the first-first layer 220a adjacent to the first reflective layer 220, and by minimizing the generation of an electric field due to band bending at the interface between adjacent reflective layers, the carrier barrier is reduced, there is a technical effect of improving the light output.

[0097] Therefore, according to the embodiment, it is possible to provide a surface-emitting laser device and a light-emitting device including the surface-emitting laser device, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflective layer.

[0098] Next, one of the further technical problems of the embodiment is to provide a surface-emitting laser device and a light-emitting device including the surface-emitting laser device, which can improve the light output while improving the voltage efficiency.

[0099] That is, in the prior art, attempts have been made to improve voltage efficiency by increasing the doping concentration to reduce resistance in order to prevent resistance from being generated in the DBR, which serves as a reflective layer. However, there is a technical contradiction, such that increasing the doping concentration causes internal light absorption due to the dopant and reduces light output.

[0100] In order to solve such technical problems, the embodiment has a technical effect such that light output can be improved and voltage efficiency can also be increased by controlling the concentration of the first conductive dopant in the reflective layer in accordance with the mode in consideration of light energy.

[0101] Specifically, refer to Figure 4A , the light energy E in the first-third layer 220c may be higher than the light energy in the first-first layer 220a and the first-second layer 220b. The first-first layer 220a may be arranged closer to the active region 230 than the first-second layer 220b.

[0102] Table 1 below shows the light energy distribution of the Al concentration and the refractive index of the first reflective layer and doping concentration data of the n-type dopant in each layer according to the embodiment.

[0103] [Table 1]

[0104] layer Al concentration (x) Refractive index (n) Light Energy (E) Doping concentration First-first layer 220a 0.12 high middle middle First to third layers 220c 0.12->0.88 middle high Low First-second layer 220b 0.88 Low middle middle First to fourth layer 220d 0.88->0.12 middle Low high

[0105] At this time, when the first reflective layer 220 includes the first conductive dopant, the concentration of the first conductive dopant of the first-third layer 220c may be lower than those of the first-first layer 220a and the first-second layer 220b.

[0106] According to the embodiment, since the light absorption of the dopant can be minimized and the light output can be improved by doping the relatively low first conductive dopant in the first-third layer 220c region where the light energy is relatively high, there is a specific technical effect, which can provide a surface emitting laser device and a light emitting device including the surface emitting laser device, which can improve light output and voltage efficiency at the same time.

[0107] In addition, the first reflective layer 220 of the embodiment may further include a first-fourth layer 220d disposed on one side of the first-second layer 220b and having a fourth concentration of aluminum. The first-fourth layer 220d may be further separated from the active region 230 rather than from the first-second layer 220b.

[0108] At this time, the light energy in the first-fourth layer 220d can be lower than the light energy in the first-first layer 220a and the first-second layer 220b. In this way, the light energy in the first-fourth layer 220d can be lower than the light energy in the first-first layer 220a, the first-second layer 220b and the first-third layer 220c.

[0109] The concentration of the first conductive dopant in the first to fourth layers 220d can be controlled to be higher than the concentration of the first conductive dopant in the first to first layer 220a and the first to second layer 220b.

[0110] For example, when the first reflective layer 220 includes Al x Ga (1-x) As (0 < x < 1), the first to first layer 220a can be Al 0.12 Ga 0.88 As, and when the first to second layer 220b is Al 0.88 Ga 0.12 As, then the first to fourth layer 220d can be Al x4 Ga (1-x4) As (0.12 ≤ x4 ≤ 0.88, x4 increases from 0.12 to 0.88).

[0111] At this time, the light energy in the first to fourth layers 220d can be lower than the light energy in the first to first layer 220a and the first to second layer 220b, respectively.

[0112] In an embodiment, the concentration of the first conductive dopant in the first to fourth layers 220d is controlled to be higher than the concentration of the first conductive dopant in the first to first layer 220a and the first to third layer 220c and the doping concentration in the first to fourth layers 220d is controlled to be maximum, and thus has a specific technical effect that the voltage efficiency can be improved through resistance improvement. At the same time, the dopant can minimize light absorption and the light output may be improved.

[0113] Figure 4B is a graph showing data of the Al concentration and the doping concentrations of dopants Si and C in a surface-emitting laser device according to an embodiment.

[0114] In Figure 4B , the horizontal axis is the distance in the direction from the second reflective layer towards the first reflective layer, and the vertical axis is the data of the Al concentration and the doping concentrations of dopants Si and C.

[0115] According to an embodiment, the first reflective layer 220 doped with Si as the first dopant may include a first to first layer 220a having a first aluminum concentration, a first to second layer 220b having a second aluminum concentration higher than the first aluminum concentration and disposed on one side of the first to first layer 220a, and a first to third layer 220c having a third aluminum concentration varying from the first aluminum concentration to the second aluminum concentration and disposed between the first to first layer 220a and the first to second layer 220b.

[0116] At this time, the Al concentration in the first-first layer 220 a or the first-second layer 220 b may not have a fixed value, but may have an Al concentration value within a predetermined range.

[0117] In addition, the upper limit value or lower limit value of the dopant concentration of Si as the first conductive dopant, or the dopant concentration of C as the second conductive dopant, may not have a specific fixed value, and the upper limit or lower limit may have a value range within a specific range.

[0118] Next, Figure 4C is second distribution data of the refractive index n in the surface emitting laser device according to the embodiment.

[0119] Figure 4D is relative to the second area B2 Figure 4C The second data of the refractive index n of the first reflective layer 220 of the surface emitting laser device according to the embodiment shown in , and Figure 4E is third data of the refractive index n of the second reflective layer 250 with respect to the third region P.

[0120] First, refer to Figure 4D In an embodiment, the first reflective layer 220 may include a first group of first reflective layers 221 and a second group of first reflective layers 222 .

[0121] At this time, the first group of first reflective layers 221 may include a plurality of layers, for example, a first-first reflective layer 221p, a first-second reflective layer 221q, a first-third reflective layer 221r, and a first-fourth reflective layer 221s.

[0122] In an embodiment, when the first-first reflective layer 221p to the first-fourth reflective layer 221s are formed as a pair, the first group of first reflective layers 221 may include a plurality of pairs. For example, in an embodiment, the first group of first reflective layers 221 may include approximately 30 to 40 pairs of the first-first reflective layer 221p to the first-fourth reflective layer 221s.

[0123] In addition, the second group of first reflective layers 222 may include a plurality of layers, for example, first to fifth reflective layers 222p, first to sixth reflective layers 222q, first to seventh reflective layers 222r, and first to eighth reflective layers 222s.

[0124] In addition, when the first to fifth reflective layers 222p to the first to eighth reflective layers 222s are formed as a pair, the second group of first reflective layers 222 may further include multiple pairs. For example, in an embodiment, when the first to fifth reflective layers 222p to the first to eighth reflective layers 222s are formed as a pair, the second group of first reflective layers 222 may include approximately 5 to 15 pairs.

[0125] In a conventional VCSEL structure, there is a problem that a carrier barrier is generated due to a band bending at an interface between adjacent DBR layers to generate an electric field, thereby degrading the light output.

[0126] For this reason, one of the technical problems of the embodiments is to provide a surface-emitting laser device and a light-emitting device including the surface-emitting laser device, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflective layer.

[0127] Reference Figure 4D , in an embodiment, the first set of first reflective layers 221 may include a first-first reflective layer 221p, a first-second reflective layer 221q, a first-third reflective layer 221r, and a first-fourth reflective layer 221s, and each layer may have a different refractive index.

[0128] For example, the first set of first reflective layers 221 may include a first-first reflective layer 221p having a first refractive index, a first-second reflective layer 221q having a second refractive index lower than the first refractive index and disposed on one side of the first-first reflective layer 221p, and a first-third reflective layer 221r having a third refractive index between the first refractive index and the second refractive index and disposed between the first-first reflective layer 221p and the first-second reflective layer 221q.

[0129] For example, the first set of first reflective layers 221 may include a first-first reflective layer 221p having a first aluminum concentration, a first-second reflective layer 221q having a second aluminum concentration higher than the first aluminum concentration and disposed on one side of the first-first reflective layer 221p, and a first-third reflective layer 221r having a third aluminum concentration varying from the first aluminum concentration to the second aluminum concentration and disposed between the first-first reflective layer 221p and the first-second reflective layer 221q.

[0130] For example, when the first set of first reflective layers 221 includes Al x Ga (1-x) As (0 < x < 1), the first-first reflective layer 221p may be Al 0.12 Ga 0.88 As, the first-second reflective layer 221q may be Al 0.88 Ga 0.12 As, and the first-third reflective layer 221r may be Al x3 Ga (1-x3) As (0.12 ≤ x3 ≤ 0.88), but the present invention is not limited thereto.

[0131] In addition, the first first reflection layer 221 may further include first - fourth reflection layers 221s, which are disposed outside the first - second reflection layers 221q and have a fourth aluminum concentration that varies from a first aluminum concentration to a second aluminum concentration.

[0132] For example, when the first first reflection layer 221 includes Al x Ga (1-x) As (0 < x < 1), the first - fourth reflection layers 221s may be Al x4 Ga (1-x4) As (0.12 ≤ x4 ≤ 0.88), but is not limited thereto.

[0133] In this way, according to the embodiment, by providing the first - third reflection layer 221r or the first - fourth reflection layer 221s having an intermediate aluminum concentration between adjacent first - first reflection layers 221p and first - second reflection layers 221q, the electric field generated due to band bending at the interface between adjacent reflection layers can be minimized, the carrier barrier can be reduced, and thus there is a technical effect that the light output can be improved.

[0134] Therefore, according to the embodiment, it is possible to provide a surface - emitting laser device and a light - emitting device including the surface - emitting laser device, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflection layer.

[0135] In addition, in the embodiment, the thickness of the first - second reflection layer 221q may be greater than the thickness of the first - first reflection layer 221p. In addition, the thickness of the first - first reflection layer 221p or the first - second reflection layer 221q may be greater than the thickness of the first - third reflection layer 221r or the first - fourth reflection layer 221s.

[0136] At this time, the first aluminum concentration of the first - first reflection layer 221p may be higher than the second aluminum concentration of the first - second reflection layer 221q. In addition, the first aluminum concentration of the first - first reflection layer 221p may be higher than the third aluminum concentration of the first - third reflection layer 221r or the fourth aluminum concentration of the first - fourth reflection layer 221s.

[0137] Therefore, since the thickness of the first - second reflection layer 221q having a relatively high aluminum concentration is thicker than the thickness of the first - first reflection layer 221p, the quality of the lattice can be improved and it helps the light output.

[0138] In addition, since the thickness of the first - first reflection layer 221p having a relatively high aluminum concentration is thicker than the thickness of the first - third reflection layer 221r or the first - fourth reflection layer 221s, the quality of the lattice can be improved and it helps the light output.

[0139] For example, since the thickness of the first-second reflective layer 221q can be about 50 to 55 nm, the thickness of the first-first reflective layer 221p can be about 40 to 45 nm, and the thickness of the first-second reflective layer 221q having a relatively high aluminum concentration is thicker than that of the first-first reflective layer 221p, which can improve the quality of the crystal lattice and contribute to light output.

[0140] In addition, since the thickness of the first-third reflective layer 221r can be about 22 to 27 nm, the thickness of the first-fourth reflective layer 221s can be about 22 to 27 nm, and the thickness of the first-second reflective layer 221q or the first-first reflective layer 221p having a relatively high aluminum concentration is thicker than that of the first-third reflective layer 221r or the first-fourth reflective layer 221s, which can improve the quality of the crystal lattice and contribute to light output.

[0141] Continuously, referring to Figure 4D , in an embodiment, the second group of first reflective layers 222 may include a first-fifth reflective layer 222p, a first-sixth reflective layer 222q, a first-seventh reflective layer 222r, and a first-eighth reflective layer 222s, and each layer may have a different refractive index.

[0142] For example, the second group of first reflective layers 222 may include a first-fifth reflective layer 222p having a fifth refractive index, a first-sixth reflective layer 222q having a sixth refractive index lower than the fifth refractive index and disposed on one side of the first-fifth reflective layer 222p, and a first-seventh reflective layer 222r having a seventh refractive index between the fifth refractive index and the sixth refractive index and disposed between the first-fifth reflective layer 222p and the first-sixth reflective layer 222q.

[0143] For example, the second group of first reflective layers 222 may include a first-fifth reflective layer 222p having a fifth aluminum concentration, a first-sixth reflective layer 222q having a sixth aluminum concentration higher than the fifth aluminum concentration and disposed on one side of the first-fifth reflective layer 222p, and a first-seventh reflective layer 222r having a seventh aluminum concentration varying from the fifth aluminum concentration to the sixth aluminum concentration and disposed between the first-fifth reflective layer 222p and the first-sixth reflective layer 222q.

[0144] For example, when the second group of first reflective layers 222 includes Al x Ga (1-x) As(0 < x < 1), the first-fifth reflective layer 222p may be Al 0.12 Ga 0.88 A, the first-sixth reflective layer 222q may be Al0.88 Ga 0.12 As, and the first - seventh reflective layer 222r can be Al x3 Ga (1-x3) As (0.12 ≤ x3 ≤ 0.88), but not limited thereto.

[0145] In addition, the second group of the first reflective layer 222 may further include a first - eighth reflective layer 222s, which is arranged outside the first - sixth reflective layer 222q and has an eighth aluminum concentration that varies from a fifth aluminum concentration to a sixth aluminum concentration.

[0146] For example, when the second group of the first reflective layer 222 includes Al x Ga (1-x) As (0 < x < 1), the first - eighth reflective layer 222s can be Al x4 Ga (1-x4) As (0.12 ≤ x4 ≤ 0.88), but not limited thereto.

[0147] In this way, according to the embodiment, by providing the first - seventh reflective layer 222r or the first - eighth reflective layer 222s having an intermediate aluminum concentration between the adjacent first - fifth reflective layer 222p and the first - sixth reflective layer 222q, the generation of an electric field caused by band bending at the interface between adjacent reflective layers can be minimized, the carrier barrier can be reduced, and thus there is a technical effect that the light output can be improved.

[0148] Therefore, according to the embodiment, it is possible to provide a surface - emitting laser device and a light - emitting device including the surface - emitting laser device, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflective layer.

[0149] In addition, in the embodiment, the thickness of the first - sixth reflective layer 222q can be greater than the thickness of the first - fifth reflective layer 222p. In addition, the thickness of the first - fifth reflective layer 222p or the first - sixth reflective layer 222q can be greater than the thickness of the first - seventh reflective layer 222r or the first - eighth reflective layer 222s.

[0150] At this time, the sixth aluminum concentration of the first - sixth reflective layer 222q can be higher than the fifth aluminum concentration of the first - fifth reflective layer 222p. In addition, the fifth aluminum concentration of the first - fifth reflective layer 222p can be higher than the seventh aluminum concentration of the first - seventh reflective layer 222r or the eighth aluminum concentration of the first - eighth reflective layer 222s.

[0151] Therefore, because the thickness of the first - sixth reflective layer 222q having a relatively high aluminum concentration is thicker than the thickness of the first - fifth reflective layer 222p, the quality of the lattice can be improved and it helps the light output.

[0152] In addition, since the thickness of the first to fifth reflective layers 222p having a relatively high aluminum concentration is thicker than that of the first to seventh reflective layers 222r or the first to eighth reflective layers 222s, it is possible to improve the quality of the lattice and facilitate light output.

[0153] For example, because the thickness of the first-sixth reflective layer 222q can be approximately 50 to 55 nm, the thickness of the first-fifth reflective layer 222p can be approximately 40 to 45 nm, and the thickness of the first-sixth reflective layer 222q having a relatively high aluminum concentration is thicker than the thickness of the first-fifth reflective layer 222p, which can improve the quality of the lattice and contribute to light output.

[0154] In addition, since the thickness of the first to seventh reflective layers 222r can be approximately 22 to 27 nm, the thickness of the first to eighth reflective layers 222s can be approximately 22 to 27 nm, and the thickness of the first to fifth reflective layers 222p or the first to sixth reflective layers 222q having a relatively high aluminum concentration is thicker than the thickness of the first to seventh reflective layers 222r or the first to eighth reflective layers 222s, which can improve the quality of the lattice and contribute to light output.

[0155] Next, one of the technical problems of the embodiment is to provide a surface emitting laser device and a light emitting device including the same, which can improve light output by minimizing the influence of a carrier barrier due to generation of an electric field in a reflective layer.

[0156] At this time, refer to Figure 3 , in the surface emitting laser device according to the embodiment, the distribution of light energy E depending on the position is shown. As it becomes relatively farther away from the active region 230, the light energy distribution becomes lower. In the embodiment, considering the light energy distribution, the concentration of the first conductive dopant in the first group of first reflective layers 221 can be controlled to be higher than the concentration of the dopant in the second group of first reflective layers 222.

[0157] For example, in an embodiment, the dopant concentration in the first group of first reflective layers 221 may be about 2.00E18, and the dopant concentration in the second group of first reflective layers 222 may be controlled to be about 1.00E18. In an embodiment, the concentration unit E18 may mean 10 18 (atoms / cm 3 For example, a concentration of 1.00E18 may mean 1.00X10 18 (atoms / cm 3 ), and the concentration 1.00E17 may mean 1.00X10 17 (atoms / cm 3 ).

[0158] In an embodiment, the n-type dopant may be silicon (Si), but is not limited thereto.

[0159] In this way, the embodiment controls the concentration of the first conductive dopant in the second group of first reflective layers 222 where the light energy distribution is relatively high to be lower than the concentration of the dopant in the first group of first reflective layers 221, and the first conductive dopant is relatively highly doped in the first group of first reflective layers 221 where the light energy is relatively low, so that in the second group of first reflective layers 222, the light absorption of the dopant is minimized and the light output is improved, and in the first group of first reflective layers 221, the voltage efficiency is improved by improving the resistance of the relatively high dopant, and thus has a specific technical effect of being able to provide a surface emitting laser device capable of simultaneously improving light output and voltage efficiency and a light-emitting device including the same.

[0160] Next, Figure 4E is relative to the third region P Figure 4C . The third data of the refractive index n of the second reflective layer 250 of the surface emitting laser device according to the embodiment is shown in FIG.

[0161] refer to Figure 4E In an embodiment, the second reflective layer 250 may include a first group of second reflective layers 251 and a second group of second reflective layers 252 .

[0162] At this time, the first group of the second reflective layer 251 may include a plurality of layers, for example, a second-first reflective layer 251p, a second-second reflective layer 251q, a second-third reflective layer 251r, and a second-fourth reflective layer 251s.

[0163] In an embodiment, when the second-first reflective layer 251p to the second-fourth reflective layer 251s are formed as a pair, the first group of second reflective layers 251 may include a plurality of pairs. For example, in an embodiment, the first group of second reflective layers 251 may include approximately two to five pairs of the second-first reflective layer 251p to the second-fourth reflective layer 251s.

[0164] In addition, the second group of second reflective layers 252 may include a plurality of layers, for example, second to fifth reflective layers 252p, second to sixth reflective layers 252q, second to seventh reflective layers 252r, and second to eighth reflective layers 252s.

[0165] In addition, when the second-fifth reflective layer 252p to the second-eighth reflective layer 252s are formed as a pair, the second group of second reflective layers 252 may include a plurality of pairs. For example, in an embodiment, when the second-fifth reflective layer 252p to the second-eighth reflective layer 252s are formed as a pair, the second group of second reflective layers 252 may include approximately 10 to 20 pairs.

[0166] One of the technical problems of the embodiments is to provide a surface-emitting laser device and a light-emitting device including the surface-emitting laser device, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflection layer.

[0167] Reference Figure 4E , in an embodiment, the first set of second reflection layers 251 may include a second-first reflection layer 251p, a second-second reflection layer 251q, a second-third reflection layer 251r, and a second-fourth reflection layer 251s, and each layer may have a different refractive index.

[0168] For example, the first set of second reflection layers 251 may include a second-first reflection layer 251p having a first refractive index, a second-second reflection layer 251q having a second refractive index lower than the first refractive index and disposed on one side of the second-first reflection layer 251p, and a second-third reflection layer 251r having a third refractive index between the first refractive index and the second refractive index and disposed between the second-first reflection layer 251p and the second-second reflection layer 251q.

[0169] For example, the first set of second reflection layers 251 may include a second-first reflection layer 251p having a first aluminum concentration, a second-second reflection layer 251q having a second aluminum concentration higher than the first aluminum concentration and disposed on one side of the second-first reflection layer 251p, and a second-third reflection layer 251r having a third aluminum concentration varying from the first aluminum concentration to the second aluminum concentration and disposed between the second-first reflection layer 251p and the second-second reflection layer 251q.

[0170] For example, when the first set of second reflection layers 251 includes Al x Ga (1-x) As (0 < x < 1), the second-first reflection layer 251p may be Al 0.12 Ga 0.88 As, the second-second reflection layer 251q may be Al 0.88 Ga 0.12 As, and the second-third reflection layer 251r may be Al 0.88 Ga 0.12 As (0.12 ≤ x3 ≤ 0.88), but not limited thereto.

[0171] In addition, the first set of second reflection layers 251 may further include a second-fourth reflection layer 251s, which is disposed outside the second-second reflection layer 251q and has a fourth aluminum concentration varying from the first aluminum concentration to the second aluminum concentration.

[0172] For example, when the first set of second reflection layers 251 includes Al x Ga(1-x) When As(0 < x < 1), the second - fourth reflective layers 251s can be Al x4 Ga (1-x4) As(0.12 ≤ x4 ≤ 0.88), but not limited thereto.

[0173] Thus, according to the embodiment, by providing the second - third reflective layer 251r or the second - fourth reflective layer 251s having an intermediate aluminum concentration between the adjacent second - first reflective layer 251p and the second - second reflective layer 251q, the generation of the electric field due to the band bending can be minimized at the interface between the adjacent reflective layers and the carrier barrier can be reduced, and thus there is a technical effect of improving the light output.

[0174] Therefore, according to the embodiment, it is possible to provide a surface - emitting laser device and a light - emitting device including the surface - emitting laser device, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of the electric field in the reflective layer.

[0175] In addition, in the embodiment, the thickness of the second - second reflective layer 251q can be greater than the thickness of the second - first reflective layer 251p. In addition, the thickness of the second - first reflective layer 251p or the second - second reflective layer 251q can be greater than the thickness of the second - third reflective layer 251r or the second - fourth reflective layer 251s.

[0176] At this time, the second aluminum concentration of the second - second reflective layer 251q can be higher than the first aluminum concentration of the second - first reflective layer 251p. In addition, the first aluminum concentration of the second - first reflective layer 251p can be higher than the third aluminum concentration of the second - third reflective layer 251r or the fourth aluminum concentration of the second - fourth reflective layer 251s.

[0177] Therefore, since the thickness of the second - second reflective layer 251q having a relatively high aluminum concentration is thicker than the thickness of the second - first reflective layer 251p, the quality of the lattice can be improved and it helps the light output.

[0178] In addition, since the thickness of the second - first reflective layer 251p having a relatively high aluminum concentration is thicker than the thickness of the second - third reflective layer 251r or the second - fourth reflective layer 251s, the quality of the lattice can be improved and it helps the light output.

[0179] For example, since the thickness of the second - second reflective layer 251q can be about 50 to 55 nm, the thickness of the second - first reflective layer 251p can be about 26 to 32 nm, and the thickness of the second - second reflective layer 251q having a relatively high aluminum concentration is thicker than the thickness of the second - first reflective layer 251p, the quality of the lattice can be improved and it helps the light output.

[0180] In addition, since the thickness of the second-third reflective layer 251r can be about 22 to 27 nm, the thickness of the second-fourth reflective layer 251s can be about 22 to 27 nm, and the thickness of the second-second reflective layer 251q or the second-first reflective layer 251p having a relatively high aluminum concentration is thicker than the thickness of the second-third reflective layer 251r or the second-fourth reflective layer 251s, which can improve the quality of the lattice and contribute to light output.

[0181] Continuously, referring to Figure 4E , in an embodiment, the second group of second reflective layers 252 may include a second-fifth reflective layer 252p, a second-sixth reflective layer 252q, a second-seventh reflective layer 252r, and a second-eighth reflective layer 252s, and each layer may have a different refractive index.

[0182] For example, the second group of second reflective layers 252 may include a second-fifth reflective layer 252p having a fifth refractive index; a second-sixth reflective layer 252q having a sixth refractive index lower than the fifth refractive index and disposed on one side of the second-fifth reflective layer 252p; and a second-seventh reflective layer 252r having a seventh refractive index between the fifth refractive index and the sixth refractive index and disposed between the second-fifth reflective layer 252p and the second-sixth reflective layer 252q.

[0183] For example, the second group of second reflective layers 252 may include a second-fifth reflective layer 252p having a fifth aluminum concentration; a second-sixth reflective layer 252q having a sixth aluminum concentration higher than the fifth aluminum concentration and disposed on one side of the second-fifth reflective layer 252p; and a second-seventh reflective layer 252r having a seventh aluminum concentration varying from the fifth aluminum concentration to the sixth aluminum concentration and disposed between the second-fifth reflective layer 252p and the second-sixth reflective layer 252q.

[0184] For example, when the second group of second reflective layers 252 includes Al x Ga (1-x) As (0 < x < 1), the second-fifth reflective layer 252p may be Al 0.12 Ga 0.88 As, the second-sixth reflective layer 252q may be Al 0.88 Ga 0.12 As, and the second-seventh reflective layer 252r may be Al x3 Ga (1-x3) As (0.12 ≤ x3 ≤ 0.88), but not limited thereto.

[0185] In addition, the second set of second reflective layers 252 may further include second - eighth reflective layers 252s, which are arranged outside the second - sixth reflective layers 252q and have an eighth aluminum concentration that varies from a fifth aluminum concentration to a sixth aluminum concentration.

[0186] For example, when the second set of second reflective layers 252 includes Al x Ga (1-x) As (0 < x < 1), the second - eighth reflective layers 252s may be Al x4 Ga (1-x4) As (0.12 ≤ x4 ≤ 0.88), but is not limited thereto.

[0187] Thus, according to the embodiment, by providing the second - seventh reflective layer 252r or the second - eighth reflective layer 252s having an intermediate aluminum concentration between the adjacent second - fifth reflective layer 252p and the second - sixth reflective layer 252q, the generation of an electric field due to band bending at the interface between adjacent reflective layers can be minimized, and the carrier barrier can be reduced, and thus there is a technical effect that the light output can be improved.

[0188] Therefore, according to the embodiment, a surface - emitting laser device and a light - emitting device including the surface - emitting laser device can be provided, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflective layer.

[0189] In addition, in the embodiment, the thickness of the second - sixth reflective layer 252q may be greater than the thickness of the second - fifth reflective layer 252p. In addition, the thickness of the second - fifth reflective layer 252p or the second - sixth reflective layer 252q may be greater than the thickness of the second - seventh reflective layer 252r or the second - eighth reflective layer 252s.

[0190] At this time, the sixth aluminum concentration of the second - sixth reflective layer 252q may be higher than the fifth aluminum concentration of the second - fifth reflective layer 252p. In addition, the fifth aluminum concentration of the second - fifth reflective layer 252p may be higher than the seventh aluminum concentration of the second - seventh reflective layer 252r or the eighth aluminum concentration of the second - eighth reflective layer 252s.

[0191] Therefore, because the thickness of the second - sixth reflective layer 252q having a relatively high aluminum concentration is thicker than the thickness of the second - fifth reflective layer 252p, the quality of the lattice can be improved and it helps the light output.

[0192] In addition, because the thickness of the second - fifth reflective layer 252p having a relatively high aluminum concentration is thicker than the thickness of the second - seventh reflective layer 252r or the second - eighth reflective layer 252s, the quality of the lattice can be improved and it helps the light output.

[0193] For example, because the thickness of the second-sixth reflective layer 252q can be approximately 50 to 55 nm, the thickness of the second-fifth reflective layer 252p can be approximately 40 to 45 nm, and the thickness of the second-sixth reflective layer 252q having a relatively high aluminum concentration is thicker than the thickness of the second-fifth reflective layer 252p, which can improve the quality of the lattice and contribute to light output.

[0194] In addition, since the thickness of the second-seventh reflective layer 252r can be approximately 22 to 27 nm, the thickness of the second-eighth reflective layer 252s can be approximately 22 to 27 nm, and the thickness of the second-sixth reflective layer 252q or the second-fifth reflective layer 252p having a relatively high aluminum concentration is thicker than the second-seventh reflective layer 252r or the second-eighth reflective layer 252s, it is possible to improve the quality of the lattice and contribute to light output.

[0195] Next, one of the technical problems of the embodiment is to provide a surface emitting laser device and a light emitting device including the same, which can improve light output by minimizing the influence of a carrier barrier due to generation of an electric field in a reflective layer.

[0196] At this time, refer to Figure 3 , in the surface emitting laser device according to the embodiment, the distribution of light energy E depending on the position is shown. As it becomes relatively farther away from the active region 230, the light energy distribution becomes lower. In the embodiment, considering the light energy distribution, the concentration of the first conductive dopant in the first group of second reflective layers 251 can be controlled to be higher than the concentration of the dopant in the second group of second reflective layers 252.

[0197] For example, in an embodiment, the dopant concentration in the first group of second reflective layers 251 may be about 7.00E17 to 1.50E18, and the dopant concentration in the second group of second reflective layers 252 may be controlled to be about 1.00E18 to 3.00E18. In an embodiment, the concentration unit 1.00E18 may mean 1.00X10 18 (atoms / cm 3 ). In an embodiment, the p-type dopant may be carbon (C), but is not limited thereto.

[0198] In this way, the embodiment controls the concentration of the second conductive dopant in the second group of second reflective layers 252 to be higher than the concentration of the dopant in the first group of second reflective layers 251, and the second conductive dopant is relatively low-doped in the first group of second reflective layers 251 where the light energy is relatively high, so that in the first group of second reflective layers 251, the light absorption of the dopant is minimized and the light output is also improved, and in the second group of second reflective layers 252, the voltage efficiency is improved by improving the resistance of the relatively high dopant, and thus has a specific technical effect of being able to provide a surface emitting laser device capable of simultaneously improving light output and voltage efficiency and a light emitting device including the surface emitting laser device.

[0199] Furthermore, according to prior art, there is a possibility that such dopants can absorb standing waves at the interface with the DBR. Therefore, in an embodiment, a large amount of doping is performed at the node position where the optical power reflectivity of the standing wave is minimum to minimize resistance, and doping is performed as low as possible at the antinode position, thereby achieving the technical effect of minimizing light absorption. The node position can refer to the point where the refractive index of each layer changes by increasing or decreasing.

[0200] Continuously, reference Figure 4E The refractive indexes of the second-first reflection layer 251p and the second-second reflection layer 251q in the first group of second reflection layers 251 may be antinode positions that do not change to a vertex or a bottom point. In addition, the refractive indexes of the second-third reflection layer 251r and the second-fourth reflection layer 251s in the first group of second reflection layers 251 may be node positions that change by rising or falling.

[0201] Therefore, in embodiments, the second conductive doping concentration of the second-third reflective layer 251r or the second-fourth reflective layer 251s may be controlled to be higher than the second conductive doping concentration of the second-first reflective layer 251p or the second-second reflective layer 251q.

[0202] For example, the second conductive doping concentration of the second-third reflective layer 251r or the second-fourth reflective layer 251s may be approximately 1.00E18 to 1.50E18, and the second conductive doping concentration of the second-first reflective layer 251p or the second-second reflective layer 251p may be approximately 6.00E17 to 8.00E17.

[0203] Therefore, in the second-third reflection layer 251r or the second-fourth reflection layer 251s which is a node position where the optical power reflectivity of the standing wave is low, a large amount of doping is performed to minimize the resistance, and in the second-first reflection layer 251p or the second-second reflection layer 251q which is a wave antinode position, low doping is performed, and thus there is a complex technical effect that can minimize light absorption.

[0204] In addition, in an embodiment, in the second-third reflective layer 251r or the second-fourth reflective layer 251s as a node position, the concentration of the second conductive dopant in the second-fourth reflective layer 251s as a node position where the refractive index increases in a direction away from the active area 230 can be controlled to be higher than the concentration of the second conductive dopant in the second-third reflective layer 251r as a node position where the refractive index decreases.

[0205] In this manner, the concentration of the second conductive dopant of the second to fourth reflective layers 251s, which are node positions where the optical reflectivity is relatively low and the refractive index increases, may be controlled to be high to improve electrical characteristics.

[0206] For example, the second conductive doping concentration of the second-fourth reflective layer 251s may be approximately 1.50E18, the second conductive doping concentration of the second-third reflective layer 251r may be approximately 1.00E18, and the second conductive doping concentration in the second-fourth reflective layer 251s having relatively low optical reflectivity may be controlled to be high to improve electrical characteristics.

[0207] Continuously, reference Figure 4E The refractive indexes of the second to fifth reflection layers 252p and the second to sixth reflection layers 252q in the second group of second reflection layers 252 may be at antinode positions, which do not change to apexes or nadirs. Furthermore, the refractive indexes of the second to seventh reflection layers 252r and the second to eighth reflection layers 252s in the second group of second reflection layers 252 may be at node positions that change by rising or falling.

[0208] In an embodiment, the second conductive doping concentration of the second-seventh reflective layer 252r or the second-eighth reflective layer 252s may be controlled to be higher than the second conductive doping concentration of the second-fifth reflective layer 252p or the second-sixth reflective layer 252q.

[0209] For example, the second conductive doping concentration of the second-seventh reflective layer 252r or the second-eighth reflective layer 252s may be about 2.00E18 to 3.00E18, and the second-fifth reflective layer 252p or the second-sixth reflective layer 252q may be about 1.00E18 to 1.50E18.

[0210] Therefore, in the second-seventh reflection layer 252r or the second-eighth reflection layer 252s, which is a node position where the optical power reflectivity of the standing wave is low, a large amount of doping is performed to minimize the resistance, and in the second-fifth reflection layer 252p or the second-sixth reflection layer 252q, which is an anti-node position, a low amount of doping is performed, and thus there is a complex technical effect that can minimize light absorption.

[0211] In addition, in an embodiment, in the second-seventh reflective layer 252r or the second-eighth reflective layer 252s, the concentration of the second conductive dopant in the second-eighth reflective layer 252s at a node position where the refractive index increases in a direction away from the active region 230 can be controlled to be higher than the concentration of the second conductive dopant in the second-seventh reflective layer 252r at a node position where the refractive index decreases.

[0212] In this manner, the concentration of the second conductive dopant in the second to eighth reflective layer 252s, which is a node position where the optical reflectivity is relatively low and the refractive index is increased, can be controlled to be high to improve electrical characteristics.

[0213] For example, the second conductive doping concentration of the second to eighth reflective layers 252s may be approximately 3.00E18, and the second conductive doping concentration of the second to seventh reflective layers 252r may be approximately 2.00E18, and the second conductive dopant concentration in the second to eighth reflective layers 252s having relatively low optical reflectivity may be controlled to be high to improve electrical characteristics.

[0214] Next, Figure 4F is secondary ion mass spectrometry (SIMS) data of the second reflective layer of the surface emitting laser device according to the embodiment, and Figure 4G yes Figure 4F Magnified view of the P2 region.

[0215] refer to Figure 4G In an embodiment, the second reflective layer 250 may include a first group of second reflective layers 251 and a second group of second reflective layers 252. The first group of second reflective layers 251 is closer to the aperture region 240 than the second group of second reflective layers 252.

[0216] For example, the first group of second reflective layers 251 may include a first-first layer 251a having a first aluminum concentration, a first-second layer 251b having a second aluminum concentration higher than the first aluminum concentration and arranged on the first-first layer 251a, and a first-fourth layer 251d having an aluminum concentration changing from the second aluminum concentration to the first aluminum concentration and arranged on the first-second layer 251b.

[0217] And the first-second layer 251b is disposed between the first-first layer 251a and the first-fourth layer 251d. The first-first layer 251a is closer to the aperture region 240 than the first-second layer 251b.

[0218] In addition, the first group of second reflective layers 251 may further include a second-fourth reflective layer 251s disposed outside the second-second reflective layer 251q and having a fourth aluminum concentration varying from the first aluminum concentration to the second aluminum concentration.

[0219] In addition, the first group of the second reflective layer 251 may include first-third layers 251c disposed between the first-second layers 251b and the first-fourth layers 251d.

[0220] In addition, in an embodiment, the second reflective layer 250 may be doped with a second conductive dopant. In an embodiment, the p-type dopant may be carbon (C), but is not limited thereto.

[0221] Furthermore, in embodiments, the second conductive doping concentration of the first-fourth layer 251 d may be higher than the second conductive doping concentration of the first-first layer 251 a and / or the first-second layer 251 b .

[0222] Therefore, in the first to fourth layers 251 d , which are node positions where the optical power reflectivity of the standing wave is low, a large amount of doping is performed to minimize resistance and improve electrical characteristics.

[0223] Furthermore, in the first-first layer 251 a which is an antinode position including other layers, low doping is performed, and thus there is a complex technical effect capable of minimizing light absorption.

[0224] Also refer to Figure 4G In an embodiment, the second group of second reflective layers 252 may include a second-first layer 252a having a first aluminum concentration; a second-second layer 252b having a second aluminum concentration higher than the first aluminum concentration and arranged on the second-first layer 252a; and a second-fourth layer 252d having a fourth aluminum concentration varying from the second aluminum concentration to the first aluminum concentration and arranged on the second-second layer 252b.

[0225] And the second-second layer 252b is arranged between the second-first layer 252a and the second-fourth layer 252d. The second-first layer 252a is closer to the aperture region 240 than the second-second layer 252b.

[0226] In addition, the second group of second reflective layers 252 may include a second-third layer 252c disposed between the second-second layer 252b and the second-fourth layer 252d.

[0227] Furthermore, in embodiments, the second conductive doping concentration of the second to fourth layers 252 d may be higher than the second conductive doping concentration of the second-first layer 252 a and / or the second-second layer 252 b .

[0228] Therefore, in the second to fourth layers 252 d , which are node positions where the optical power reflectivity of the standing wave is low, a large amount of doping is performed to minimize resistance, and electrical characteristics can be improved.

[0229] Furthermore, in the second-first layer 252 a which is an antinode position including other layers, low doping is performed, and thus there is a complex technical effect capable of minimizing light absorption.

[0230] Again, reference Figure 4G In an embodiment, the second reflective layer 250 may include a third group of second reflective layers 253 arranged in the third region P3. The third group of second reflective layers 253 is closer to the aperture region 240 than the first group of second reflective layers 251. Two or three third groups of second reflective layers 253 can be arranged in the third region P3.

[0231] Furthermore, in an embodiment, the average second conductive doping concentration of the third group of second reflective layers 253 may be less than the average second conductive doping concentration of the first group of second reflective layers 251 arranged in the second region P2.

[0232] Furthermore, low doping is performed in the third group of second reflective layers 253 near the aperture region 240 , and thus there is a complex technical effect capable of minimizing light absorption.

[0233] Furthermore, in the first group of second reflective layers 251 and / or the second group of second reflective layers 252 away from the aperture region 240 where the optical power reflectivity of the standing wave is low, a large amount of doping is performed to minimize resistance and improve electrical characteristics.

[0234] Table 2 below shows chip characteristic data in the prior art (comparative example) and the embodiment.

[0235] According to the embodiment, as shown in Table 2, it can be seen that light output, voltage characteristics, etc. are significantly improved.

[0236] [Table 2]

[0237]

[0238] Next, refer to Figure 3 , in a surface-emitting laser device according to an embodiment, the light energy distribution depending on the position is shown. As described above, the light energy distribution becomes lower as it becomes relatively farther away from the active region 230. In an embodiment, the concentration of the first conductive dopant in the first group of first reflective layers 221 can be controlled to be higher than the concentration of the dopant in the second group of first reflective layers 222.

[0239] For example, reference Figure 2 In an embodiment, the first reflective layer 220 may include a first group of first reflective layers 221 arranged on one side of the active region 230 and a second group of first reflective layers 222 arranged closer to the active region 230 than the first group of first reflective layers 221 .

[0240] At this time, light energy in the second group of first reflective layers 222 disposed adjacent to the active area 230 becomes higher than light energy in the first group of first reflective layers 221 .

[0241] Taking into account the light energy distribution, the embodiment controls the concentration of the first conductive dopant in the second group of first reflective layers 222 to be lower than the concentration of the dopant in the first group of first reflective layers 221, and the first conductive dopant is relatively highly doped in the first group of first reflective layers 221 where the light energy is relatively low, so that in the second group of first reflective layers 222, the light absorption of the dopant is minimized and the light output is also improved, and in the first group of first reflective layers 221, the voltage efficiency is improved by improving the relatively high resistance of the dopant, and thus has a specific technical effect of being able to provide a surface emitting laser device capable of simultaneously improving light output and voltage efficiency and a light emitting device including the surface emitting laser device.

[0242] For example, the dopant concentration in the first group of first reflective layers 221 may be approximately 2.00E18, and the dopant concentration in the second group of first reflective layers 222 may be approximately 1.00E18, but are not limited thereto. Furthermore, in an embodiment, the second reflective layer 250 may include a first group of second reflective layers 251 disposed adjacent to the active region 230 and a second group of second reflective layers 252 disposed spaced apart from the active region 230 instead of the first group of second reflective layers 251.

[0243] At this time, light energy in the first group of second reflective layers 251 disposed adjacent to the active area 230 becomes higher than light energy in the second group of second reflective layers 252 .

[0244] In this way, taking into account the light energy distribution, the embodiment controls the concentration of the second conductive dopant in the first group of second reflective layers 251 to be lower than the concentration of the dopant in the second group of second reflective layers 252, and the second conductive dopant is relatively highly doped in the second group of second reflective layers 252 area where the light energy is relatively low, so that in the first group of second reflective layers 251, the light absorption of the dopant is minimized and the light output is also improved, and in the second group of second reflective layers 252, the voltage efficiency is improved by improving the resistance of the dopant, and thus has a specific technical effect of being able to provide a surface emitting laser device capable of simultaneously improving light output and voltage efficiency and a light emitting device including the surface emitting laser device.

[0245] <Active Area>

[0246] See again Figure 2 , embodiments may include an active region 230 on the first reflective layer 220 .

[0247] The active region 230 may include an active layer 232, a first cavity 231 disposed below the active layer 232, and a second cavity 233 disposed thereon. The active region 230 of the embodiment may include the first cavity 231 and the second cavity 233, or may include only one of them.

[0248] The active region 230 may be disposed between the first reflective layer 220 and the second reflective layer 250. The active region 230 of the embodiment may include an active layer 232 of any one of a single-well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure.

[0249] The active layer 232 may be formed of a quantum well layer 232a and a barrier layer 232b using a compound semiconductor material of group III-V elements. For example, a structure of one to three pairs, such as InGaAs / Al x GaAs, AlGaInP / GaInP, AlGaAs / AlGaAs, AlGaAs / GaAs, and GaAs / InGaAs, but not limited thereto. The quantum well layer 232a may be formed of a material having a bandgap smaller than that of the quantum barrier layer 232b. The active layer 232 may not be doped with a dopant.

[0250] The first cavity 231 and the second cavity 233 may be formed of Al y Ga (1-y) As (0 < y < 1), but not limited thereto. For example, the first cavity 231 and the second cavity 233 may each include a plurality of Al y Ga (1-y) As As layers.

[0251] In an embodiment, an insulating region 242 is disposed on the active region 230, and an aperture 241 is defined by the insulating region 242.

[0252] The insulating region 242 may be formed of an insulating layer such as alumina and may be used as a current insulating region, and the aperture 241 as a non-insulating layer may be disposed in the central region. The aperture 241 and the insulating region 242 may be referred to as an aperture region 240.

[0253] Specifically, the aperture region 240 may include aluminum gallium arsenide. At this time, the insulating region 242 may be formed because AlGaAs in the aperture region 240 reacts with H2O and its edge becomes alumina (Al2O3), and the central region that does not react with H2O may be the aperture 241 made of AlGaAs.

[0254] The insulating region 242 may include multiple layers, for example, a first insulating layer 242a and a second insulating layer 242b. The thickness of the first insulating layer 242a may be formed the same or differently.

[0255] According to an embodiment, light emitted from the active region 230 may be emitted to the upper region through the aperture 241, and the light transmittance of the aperture 241 may be higher than that of the insulating region 242.

[0256] <Second reflective layer>

[0257] The second reflective layer 250 may be disposed on the aperture region 240 including the insulating region 242.

[0258] The second reflective layer 250 may include a gallium-based compound such as AlGaAs, and the second reflective layer 250 may be doped with a second conductive dopant. For example, the second conductive dopant may be a p-type dopant such as Mg, Zn, Ca, Sr, and Ba. At the same time, the first reflective layer 220 may be doped with a p-type dopant, and the second reflective layer 250 may be doped with an n-type dopant.

[0259] The second reflective layer 250 may be a distributed Bragg reflector (DBR). For example, the second reflective layer 250 may be a structure in which multiple layers made of materials with different refractive indices are alternately stacked at least once.

[0260] Each layer of the second reflective layer 250 may include AlGaAs, and specifically, may be made of a semiconductor material having a composition formula of Al x Ga (1-x) As (0 < x < 1). Here, when Al increases, the refractive index of each layer may decrease, and when Ga increases, the refractive index of each layer may increase. In addition, the thickness of each layer of the second reflective layer 250 may be λ / 4n, where λ may be the wavelength of light emitted from the active layer, and n may be the refractive index of each layer with respect to the light of the above wavelength.

[0261] The second reflective layer 250 having such a structure may have a reflectivity of 99.9% with respect to light in the wavelength region of 940 nm.

[0262] The second reflective layer 250 may be formed by alternately stacking layers, and the number of layer pairs in the first reflective layer 220 may be greater than the number of layer pairs in the second reflective layer 250. In this regard, as described above, the reflectivity of the first reflective layer 220 is about 99.999%, which may be greater than the reflectivity of the second reflective layer 250, 99.9%.

[0263] In an embodiment, the second reflective layer 250 may include a first group of second reflective layers 251 disposed adjacent to the active region 230 and a second group of second reflective layers 252 disposed to be spaced apart from the active region 230 instead of the first group of second reflective layers 251 .

[0264] As described above, the concentration of the first conductive dopant in the first group of second reflective layers 251 may be lower than the concentration of the dopant in the second group of second reflective layers 252 .

[0265] For example, the first group of second reflective layers 251 may include approximately one to five pairs of a first group of second-first layers 251a and a first group of second-second layers 251b. The first group of second-first layers 251a may be formed thicker than the first group of second-second layers 251b. For example, the first group of second-first layers 251a may be formed to a thickness of approximately 40 to 60 nm, and the first group of second-second layers 251b may be formed to a thickness of approximately 20 to 30 nm.

[0266] In addition, the second group of second reflective layers 252 may include approximately 5 to 15 pairs of second group second-first layers 252a and second group second-second layers 252b. The second group second-first layers 252a may be formed thicker than the second group second-second layers 252b. For example, the second group second-first layers 252a may be formed to a thickness of approximately 40 to 60 nm, and the second group second-second layers 252b may be formed to a thickness of approximately 20 to 30 nm.

[0267] <Second Contact Electrode, Passivation Layer, Second Electrode>

[0268] refer to Figure 1 The surface emitting laser device 200 according to the embodiment may mesa-etch from the second reflective layer 250 to the insulating region 242 and the active region 230 in the region around the aperture 241. In addition, mesa-etching may be performed up to a portion of the first reflective layer 220.

[0269] The second contact electrodes 255 may be arranged on the second reflective layer 250 such that the exposed area of ​​the second reflective layer 250 in the region between the second contact electrodes 255 may correspond to the aperture 241 in the central region of the insulating region 242 described above. Here, the width of the aperture 241 may be wider or narrower than the width between the second contact electrodes 255. When the width of the aperture 241 is narrower than the width between the second contact electrodes 255, light emitted from the active region 230 may be diffused and transmitted, and when the width of the aperture 241 is wider than the width between the second contact electrodes 255, light emitted from the active region 230 may be concentrated and transmitted. The second contact electrodes 255 may improve the contact characteristics between the second reflective layer 250 and the second electrode 280 described later.

[0270] exist Figure 1 , the passivation layer 270 may be disposed on the side surfaces and upper surfaces of the mesa-etched light emitting structure and on the upper surface of the first reflective layer 220. The passivation layer 270 may also be disposed on the side surfaces of the surface emitting laser device 200 separated into device units to protect and isolate the surface emitting laser device 200. The passivation layer 270 may be made of an insulating material such as nitride or oxide.

[0271] The passivation layer 270 may be thinner than the second contact electrode 255 on the upper surface of the light emitting structure, so that the second contact electrode 255 may be exposed at the upper portion of the passivation layer 270. The second electrode 280 may be arranged to electrically contact the exposed second contact electrode 255, and the second electrode 280 may extend to the upper portion of the passivation layer 270 to receive current from the outside.

[0272] The second electrode 280 may be made of a conductive material such as metal. For example, the second electrode 280 may be formed of a single layer or multilayer structure including at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (AU).

[0273] <Manufacturing method>

[0274] In the following, reference will be made to Figures 5 to 8 A method of manufacturing a surface emitting laser device according to an embodiment is described.

[0275] First, if Figure 5 As shown in FIG, a light emitting structure including a first reflective layer 220 , an active area 230 and a second reflective layer 250 is formed on a first substrate 210 .

[0276] The first substrate 210 may be formed of a material suitable for growing a semiconductor material or a carrier wafer. The first substrate 210 may be formed of a material having excellent thermal conductivity and may include a conductive substrate or an insulating substrate.

[0277] For example, in an embodiment, a GaAs substrate of the same kind as the first reflective layer 220 may be used as the first substrate 210. When the first substrate 210 and the first reflective layer 220 are of the same kind, lattice constants match each other, so that defects such as lattice mismatch do not occur in the first reflective layer 220.

[0278] The first reflective layer 220 may be a structure in which layers formed of materials having different refractive indices are alternately stacked at least once.

[0279] Since the first reflective layer 220 may have a DBR structure as described above, AlGaAs may be supplied and grown. At this time, AlGaAs may be grown by varying the supply amounts of Al and Ga. x Ga(1-x) A first reflective layer 220 of a semiconductor material having a composition formula of As(0 < x < 1).

[0280] For example, the first reflective layer 220 can be grown by using methods such as chemical vapor deposition (CVD), molecular beam epitaxy (MBE), sputtering, or hydride vapor phase epitaxy (HVPE).

[0281] The first reflective layer 220 can be doped with a first conductivity type. For example, the first conductive dopant can include n-type dopants such as Si, Ge, Sn, Se, and Te.

[0282] In addition, the first reflective layer 220 can include a gallium-based compound. For example, AlGaAs, but not limited thereto. The first reflective layer 220 can be a distributed Bragg reflector (DBR). For example, the first reflective layer 220 can be a structure in which layers formed of materials having different refractive indices are alternately stacked at least once.

[0283] Next, an active region 230 can be formed on the first reflective layer 220.

[0284] The active region 230 can include an active layer 232, a first cavity 231 disposed below the active layer 232, and a second cavity 233 disposed thereon. The active region 230 of the embodiment can include the first cavity 231 and the second cavity 233, or can include only one of them.

[0285] For example, the active layer 232 can include any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure.

[0286] Then, a pre-aperture region 245 can be formed on the active region 230.

[0287] The pre-aperture region 245 can be made of a conductive material and can be made of the same material as the first reflective layer 220 and the second reflective layer 250, but not limited thereto.

[0288] When the pre-aperture region 245 includes AlGaAs, the pre-aperture region 245 can be formed of a semiconductor material having a composition formula of Al x Ga (1-x) As(0 < x < 1). For example, it can have a composition formula of Al 0.98 Ga 0.02 As.

[0289] Then, a second reflective layer 250 can be formed on the pre-aperture region 245.

[0290] The second reflective layer 250 may be doped with a second conductivity type. The second reflective layer 250 may include a gallium-based compound, such as AlGaAs, but is not limited thereto.

[0291] The second reflective layer 250 may be a distributed Bragg reflector (DBR). For example, the second reflective layer 250 may be a structure in which layers formed of materials having different refractive indices are alternately stacked at least once. For example, the second reflective layer 250 may include AlGaAs, and specifically, may be made of a semiconductor material having a composition formula of Al x Ga (1-x) As (0 < x < 1).

[0292] In addition, the thickness of each layer of the second reflective layer 250 may be λ / 4n, where λ may be the wavelength of the light emitted from the active region 230, and n may be the refractive index of each layer with respect to the light of the above wavelength. Here, λ may be from 650 to 980 nanometers (nm), and n may be the refractive index of each layer. The second reflective layer 250 having such a structure may have a reflectivity of 99.999% with respect to light in the wavelength region of 940 nm.

[0293] The second reflective layer 250 may include a gallium-based compound such as AlGaAs, and the second reflective layer 250 may be doped with a second conductive dopant. For example, the second conductive dopant may be a p-type dopant such as Mg, Zn, Ca, Sr, Ba, and C. Meanwhile, the first reflective layer 220 may be doped with a p-type dopant, and the second reflective layer 250 may be doped with an n-type dopant.

[0294] The second reflective layer 250 having such a structure may have a reflectivity of 99.9% with respect to light in the wavelength region of 940 nm.

[0295] Then, as Figure 6 shown, mesa etching may be performed on the light-emitting structure by using a predetermined mask 300. At this time, mesa etching may be performed from the second reflective layer 250 to the pre-aperture region 245 and the active region 230, and mesa etching may be performed until a part of the first reflective layer 220. In the mesa etching, the pre-aperture region 245 and the active region 230 may be removed from the second reflective layer 250 in the peripheral region by an inductively coupled plasma (ICP) etching method. In the mesa etching region, the side surface may be etched with a slope.

[0296] Then, as Figure 7 shown, the edge region of the pre-aperture region may be changed to an insulating region 242, and for example, may be changed by wet oxidation.

[0297] For example, when oxygen is supplied from the edge region of the pre-aperture region 245, the AlGaAs in the pre-aperture region may react with H2O to form aluminum oxide (Al2O3). At this time, by controlling the reaction time, etc., the central region of the pre-aperture region may not react with oxygen, and only the edge region may react with oxygen, thereby forming aluminum oxide. In addition, the edge region of the pre-aperture region may be changed into the insulating region 242 by ion implantation, but is not limited thereto. During ion implantation, photons may be supplied at an energy level of 300keV or higher.

[0298] After the above reaction step, conductive AlGaAs can be arranged in the central region of aperture region 240, and non-conductive Al2O3 can be arranged in the edge region. Since AlGaAs in the central region is the portion through which light emitted from active region 230 enters the upper region, it can be referred to as aperture 241 as described above.

[0299] Then, if Figure 8 As shown in FIG, the second contact electrode 255 may be arranged on the second reflective layer 250 so that an area of ​​the second reflective layer 250 exposed in an area between the second contact electrodes 255 may correspond to the aperture 241 which is the central area of ​​the above-described aperture area 240. The second contact electrode 255 may improve contact characteristics between the second reflective layer 250 and a second electrode 280 described later.

[0300] Then, the passivation layer 270 disposed on the second contact electrode 255 may be thinner than the second contact electrode 255 on the upper surface of the light emitting structure, and at this time, the second contact electrode 255 may be exposed above the passivation layer 270 .

[0301] The passivation layer 270 may include at least one of polyimide, silicon dioxide (SiO 2 ), and silicon nitride (Si 3 N 4 ).

[0302] Then, the second electrode 280 may be disposed to electrically contact the exposed second contact electrode 255 , and the second electrode 280 may extend over the passivation layer 270 to receive current.

[0303] The second electrode 280 may be made of a conductive material such as metal. For example, the second electrode 280 may be formed of a single layer or multilayer structure including at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (AU).

[0304] The first electrode 215 may be disposed under the first substrate 210. Before disposing the first electrode 215, a portion of the bottom surface of the first substrate 210 may be removed by a predetermined grinding process, etc., thereby improving heat radiation efficiency.

[0305] The first electrode 215 may be made of a conductive material such as metal. For example, the first electrode 215 may be formed of a single layer or multilayer structure including at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (AU).

[0306] The surface-emitting laser device can be a laser diode, and the interior of the two reflective layers can function as a resonator. Electrons and holes are supplied from the first reflective layer 220 of the first conductivity type and the second reflective layer 250 of the second conductivity type to the active layer, allowing light emitted from the active region 230 to be reflected and amplified within the resonator. When the threshold current is reached, the light can be emitted to the outside through the aperture 241.

[0307] Light emitted from the surface emitting laser device according to the embodiment may be light of a single wavelength and a single phase, and the single wavelength region may vary depending on the compositions of the first reflective layer 220 , the second reflective layer 250 , and the active region 230 .

[0308] In addition, see Figures 9 to 14 , a method of manufacturing a surface emitting laser device according to a second embodiment will be described. In the following description, in order to improve heat radiation performance, a process of forming a light emitting structure on a predetermined growth substrate 190 and then removing the growth substrate 190 has been described, but the manufacturing method is not limited thereto.

[0309] First, if Figure 9 As shown in FIG, a light emitting structure including a second reflective layer 250 , an active area 230 and a first reflective layer 220 is formed on a growth substrate 190 .

[0310] The growth substrate 190 may be formed of a material suitable for growing a semiconductor material or a carrier wafer. The growth substrate 190 may be formed of a material having excellent thermal conductivity and may include a conductive substrate or an insulating substrate.

[0311] For example, in an embodiment, a GaAs substrate of the same kind as the second reflective layer 250 may be used as the growth substrate 190. When the growth substrate 190 and the second reflective layer 250 are of the same kind, lattice constants match and defects such as lattice mismatch may not occur in the second reflective layer.

[0312] In addition, an etch stop layer 192 may be formed on the growth substrate 190 .

[0313] Then, a second reflective layer 250 may be formed on the growth substrate 190 or the etch stop layer 192 .

[0314] The second reflective layer 250 may have a structure in which a third layer (not shown) and a fourth layer (not shown) made of materials having different refractive indices are alternately stacked at least once.

[0315] Since the second reflective layer 250 can have the DBR structure as described above, AlGaAs, which is the material for the third and fourth layers, can be supplied and grown. At this time, by varying the supply amounts of Al and Ga, the second reflective layer 250 made of a semiconductor material having a composition formula of Al x Ga (1-x) As (0 < x < 1) can be grown.

[0316] For example, the third layer can include Al 0.88 Ga 0.12 As, the fourth layer can be grown as Al 0.16 Ga 0.84 As, and can be grown by methods of use such as chemical vapor deposition (CVD), molecular beam epitaxy (MBE), sputtering, hydride vapor phase epitaxy (HVPE), etc.

[0317] Then, a pre-aperture region 245 can be formed on the second reflective layer 250. The pre-aperture region 245 can be made of a conductive material and can be made of the same material as the first reflective layer 220 and the second reflective layer 250, but is not limited thereto.

[0318] When the pre-aperture region 245 includes AlGaAs, the pre-aperture region 245 can be formed of a semiconductor material having a composition formula of Al x Ga (1-x) As (0 < x < 1), for example, can have a composition formula of Al 0.98 Ga 0.02 As.

[0319] Then, the active region 230 and the first reflective layer 220 can be formed on the pre-aperture region 245. The active region 230 can include an active layer 232, a first cavity 231 disposed below the active layer 232, and a second cavity 233 disposed thereon. The active region 230 of the embodiment can include the first cavity 231 and the second cavity 233, or can include only one of them.

[0320] The active layer 232 can include any one of a single-well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure.

[0321] The active layer 232 can be formed of a quantum well layer and a quantum barrier layer using a compound semiconductor material of group III-V elements. For example, paired structures such as AlGaInP / GaInP, AlGaAs / AlGaAs, AlGaAs / GaAs, and GaAs / InGaAs, but is not limited thereto. The quantum well layer can be formed of a material having a band gap smaller than that of the quantum barrier layer.

[0322] The first reflective layer 220 may be doped with a first conductive type. The first reflective layer 220 may include a gallium-based compound, such as AlGaAs, but is not limited thereto.

[0323] The first reflective layer 220 may be a distributed Bragg reflector (DBR). For example, the first reflective layer 220 may have a structure in which a first layer (not shown) and a second layer (not shown) made of materials having different refractive indices are alternately stacked at least once.

[0324] The first layer and the second layer may include AlGaAs, and specifically, may be made of a semiconductor material having a composition formula of Al x Ga (1-x) As (0 < x < 1). Here, as the Al in the first layer or the second layer increases, the refractive index of each layer may decrease, and as the Ga increases, the refractive index of each layer may increase.

[0325] In addition, the thickness of each of the first layer and the second layer may be λ / 4n, where λ may be the wavelength of the light generated in the active region 230, and n may be the refractive index of each layer with respect to the light of the above wavelength. Here, λ may be from 650 to 980 nanometers (nm), and n may be the refractive index of each layer. The first reflective layer 220 having such a structure may have a reflectance of 99.999% with respect to the light in the wavelength region of 940 nm.

[0326] The thicknesses of the first layer and the second layer may be determined depending on the corresponding refractive index and wavelength λ of the light emitted in the active region 230.

[0327] The first reflective layer 220 may be doped with a first conductive dopant. For example, the first conductive dopant may include an n-type dopant such as Si, Ge, Sn, Se, and Te.

[0328] Then, as Figure 10 shown, the second substrate 212 may be bonded to the first reflective layer 220. In an embodiment, the second substrate 212 may be bonded to the first reflective layer 220 by inserting an adhesive layer 260.

[0329] The adhesive layer 260 may be formed of a single layer or multiple layers, and may include a first adhesive layer 260a and a second adhesive layer 260b. For example, the second adhesive layer 260b may be disposed at the lower part of the second substrate 212, the first adhesive layer 260a may be disposed at the upper part of the first reflective layer 220, and the second adhesive layer 260b and the first adhesive layer 260a may be bonded to each other so that the second substrate 212 and the first reflective layer 220 may be bonded.

[0330] The adhesive layer 260 may include at least one of AuSn, NiSn, and InAu.

[0331] The second substrate 212 may be a conductive substrate or a non-conductive substrate. When a conductive substrate is used, a metal having excellent electrical conductivity may be used. Since heat generated during operation of the surface-emitting laser device 200 should be sufficiently dissipated, a metal or silicon (Si) substrate having high thermal conductivity may be used. When a non-conductive substrate is used, an aluminum nitride substrate such as an AlN substrate may be used.

[0332] Then, the first electrode 215 may be disposed on the second substrate 212 .

[0333] The first electrode 215 may be made of a conductive material such as metal. For example, the first electrode 215 may be formed of a single layer or multilayer structure including at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (AU).

[0334] Then, if Figure 11 , the growth substrate 190 may be separated. The removal of the growth substrate 190 may be performed by a laser lift-off (LLO) method using an excimer laser or the like in the case of a sapphire substrate, or may be performed by dry and wet etching methods.

[0335] As an example of a laser lift-off method, when an excimer laser having a wavelength in a predetermined area is focused and irradiated in the direction of the growth substrate 190, thermal energy is concentrated on the interface between the growth substrate 190 and the second reflective layer 250 so that the interface between the growth substrate 190 and the second reflective layer 250 is separated into gallium molecules and nitrogen molecules, and the separation of the growth substrate 190 can occur instantaneously at the portion through which the laser passes.

[0336] Here, the etch stop layer 192 may protect the second reflective layer 220 when the growth substrate 190 is removed from the light emitting structure.

[0337] Then, if Figure 12 As shown in , the light emitting structure may be mesa-etched using a predetermined mask 300. At this time, mesa etching may be performed from the second reflective layer 250 to the pre-aperture region 245 and the active region 230, and mesa etching may be performed up to a portion of the first reflective layer 220. In the mesa etching, the aperture region 240 and the active region 230 may be removed from the second reflective layer 250 in the peripheral region by an inductively coupled plasma (ICP) etching method. In the mesa-etched region, the side surface may be etched with a slope.

[0338] Then, if Figure 13As shown in FIG, the edge region of the pre-aperture region may be changed into the insulating region 242, and may be changed, for example, by wet oxidation.

[0339] For example, when oxygen is supplied from the edge region of the pre-aperture region, the AlGaAs in the pre-aperture region may react with H2O to form aluminum oxide (Al2O3). At this time, by controlling the reaction time, etc., the central region of the pre-aperture region may not react with oxygen, and only the edge region may react with oxygen, thereby forming aluminum oxide. In addition, the edge region of the pre-aperture region may be changed into the insulating region 242 by ion implantation, but is not limited thereto. During ion implantation, photons may be supplied at an energy level of 300keV or higher.

[0340] After the above reaction step, conductive AlGaAs may be arranged in the central region of aperture region 240, and non-conductive Al2O3 may be arranged in the edge region. Since the AlGaAs in the central region is a portion through which light emitted from active region 230 enters the upper region, it can be referred to as aperture 241 as described above.

[0341] Then, if Figure 14 As shown in FIG, the second contact electrode 255 may be arranged on the second reflective layer 250 so that an area of ​​the second reflective layer 250 exposed in an area between the second contact electrodes 255 may correspond to the aperture 241 which is the central area of ​​the above-described aperture area 240. The second contact electrode 255 may improve contact characteristics between the second reflective layer 250 and a second electrode 280 described later.

[0342] Then, the passivation layer 270 disposed on the second contact electrode 255 may be thinner than the second contact electrode 255 on the upper surface of the light emitting structure, and at this time, the second contact electrode 255 may be exposed above the passivation layer.

[0343] The passivation layer 270 may include at least one of polyimide, silicon dioxide (SiO 2 ), and silicon nitride (Si 3 N 4 ).

[0344] Then, the second electrode 280 may be disposed to electrically contact the exposed second contact electrode 255 , and the second electrode 280 may extend over the passivation layer 270 to receive current.

[0345] The second electrode 280 may be made of a conductive material such as metal. For example, the second electrode 280 may be formed of a single layer or multilayer structure including at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (AU).

[0346] Then, third to fifth embodiments will be described.

[0347] Figure 15 is an exemplary view of the energy band diagram 203 in a surface-emitting laser device according to the third embodiment, Figure 16 is an exemplary view of the energy band diagram 204 in a surface-emitting laser device according to the fourth embodiment, Figure 17A and 17B is doping concentration data in the active region of a surface-emitting laser device according to an embodiment. Figure 18 is an exemplary view of the energy band diagram 205 in a surface-emitting laser device according to the fifth embodiment.

[0348] (Third Embodiment)

[0349] Figure 15 is an exemplary view of the energy band diagram 203 in a surface-emitting laser device according to the third embodiment.

[0350] The third embodiment may adopt the technical features of the first and second embodiments.

[0351] For example, referring to Figure 15 , in an embodiment, when the first reflective layer 220 includes Al x Ga (1-x) As (0 < x < 1), a grading may be applied to the concentration of Al to minimize the generation of an electric field between adjacent reflective layers.

[0352] For example, when the first reflective layer 220 includes a first layer 220p with a first aluminum concentration and a second layer 220q with a second aluminum concentration, a third layer 220r with a third aluminum concentration may be inserted between the first layer 220p with the first aluminum layer concentration and the second layer 220q with the second aluminum concentration, and the aluminum concentration of the third layer 220r may have a value between the aluminum concentration of the first layer 220p and the aluminum concentration of the second layer 220q.

[0353] For example, the first reflective layer 220 may insert a third layer 220r between a first layer 220p of Al 0.12 Ga 0.88 AS and a second layer 220q of Al 0.88 Ga 0.12 As, and the third layer 220r is Al x3 Ga (1-x3) As (0.12 ≤ x3 ≤ 0.88). In this way, according to the embodiment, by providing a third layer 220r with an intermediate aluminum concentration between the first layer 220p and the second layer 220q, the generation of an electric field due to energy band bending can be minimized at the interface between adjacent reflective layers to reduce the carrier barrier, and thus there is a technical effect of being able to improve the light output.

[0354] Therefore, according to the embodiment, a surface-emitting laser device and a surface-emitting laser package including the surface-emitting laser device can be provided, which can improve the light output by minimizing the influence of the carrier barrier caused by the generation of an electric field in the reflective layer.

[0355] Hereinafter, the main technical features of the third embodiment will be mainly described.

[0356] Reference Figure 15 , the third embodiment may include an active region 230 on the first reflective layer 220.

[0357] The active region 230 may include an active layer 232, a first cavity 231 disposed below the active layer 232, and a second cavity 233 disposed thereon. The active region 230 of the embodiment may include the first cavity 231 and the second cavity 233, or may include only one of them.

[0358] The first cavity 231 and the second cavity 233 may be formed of Al y Ga (1-y) As (0 < y < 1), but is not limited thereto. For example, the first cavity 231 and the second cavity 233 may each include a plurality of Al y Ga (1-y) As layers.

[0359] For example, the first cavity 231 may include a first-first cavity layer 231a and a first-second cavity layer 231b. The first-first cavity layer 231a may be further separated from the active layer 232 than from the first-second cavity layer 231b. The first-first cavity layer 231a may be formed thicker than the first-second cavity layer 231b, but is not limited thereto.

[0360] One of the technical problems of the embodiment is to provide a surface-emitting laser device and a surface-emitting laser package including the surface-emitting laser device that can improve the voltage efficiency and the light output.

[0361] To solve such a technical problem, the embodiment may provide a surface-emitting laser device having a technical effect of improving the voltage efficiency by reducing the resistance in the active region and improving the light output, and a surface-emitting laser package including the surface-emitting laser device.

[0362] First, reference Figure 15In the third embodiment, the active region 230 may include a first cavity 231 arranged on the first reflective layer 220, and an active layer 232 including a quantum well 232a and a quantum wall 232b and arranged on the first cavity 231, and the first cavity 231 may be adjacent to the first reflective layer 220 and may include a first conductive first doping layer 261.

[0363] According to the third embodiment, by including the first conductive first doping layer 261 in a portion of the first cavity 231 and by reducing resistance compared to the existing active area, voltage efficiency can be improved by reducing resistance in the active area, and thus there is a technical effect of being able to improve light output.

[0364] For example, in the third embodiment, when the first cavity 231 includes the first-first cavity layer 231a and the first-second cavity layer 231b, by including the first conductive first doping layer 261 in the first-first cavity layer 231a and by reducing the resistance compared to the conventional active region, there is a technical effect of improving voltage efficiency by reducing the resistance in the active region and being able to improve light output.

[0365] Table 3 below shows characteristic data of the surface emitting laser devices of the comparative example and the embodiment: The comparative example is a case where no doping is performed in the cavity.

[0366] [Table 3]

[0367] type Comparison Examples Example Number of emitters 202 202 Wp(nm) 943.2 942.4 Vf(V) 2.19 2.07 PCE (%) 38.9 39.3

[0368] In the third embodiment, as doping is performed in the cavity, the operating voltage Vf is lowered by reducing the resistance in the active region compared to the comparative example, and thus there is a technical effect that light efficiency or light output can be improved.

[0369] In the third embodiment, the thickness of the first conductive first doping layer 261 is controlled to be 10% to 70% of the thickness of the first cavity 231, thereby improving voltage efficiency and light output by reducing the resistance of the active region. In this case, when the area of ​​the first conductive first doping layer 261 exceeds 70% of the area of ​​the first cavity 231, light output may be reduced due to light absorption in the doped region, and when this area is less than 10%, the contribution of the resistance reduction effect may be low. Furthermore, in embodiments, the area of ​​the first conductive first doping layer 261 can be controlled to be 20% to 50% of the area of ​​the first cavity 231.

[0370] In an embodiment, the "area" may be compared based on the "width" that each layer occupies. Additionally, the "area" may be the "volume" that each layer occupies.

[0371] In an embodiment, the concentration of the first conductive dopant in the first conductive first doped layer 261 is controlled to be in the range of 1x10 17 to 8x10 17 (atoms / cm 3 ), and thus there is a technical effect of improving voltage efficiency and light output by reducing the resistance in the active region. At this time, when the concentration of the first conductive dopant in the first conductive - first doped layer 261 exceeds its upper limit, the light output may decrease due to light absorption in the doped region, and when the concentration is less than its lower limit, the contribution of the resistance reduction effect may be low.

[0372] At this time, in an embodiment, the concentration of the first conductive dopant in the first conductive first doped layer 261 located in the first cavity 231 is controlled to be lower than the concentration of the first conductive dopant in the first reflective layer 220, so that light absorption in the doped region can be prevented and voltage efficiency can be improved by reducing the resistance in the active region, thereby improving the light output.

[0373] For example, when the concentration of the first conductive dopant in the first conductive - first doped layer 261 is in the range of 1x10 18 to 2x10 18 (atoms / cm 3 ), the concentration of the first conductive dopant in the first conductive - first doped layer 261 is controlled to be in the range of 1x10 17 to 8x10 17 (atoms / cm 3 ), and thus there is a technical effect of improving voltage efficiency and light output by reducing the resistance in the active region.

[0374] In addition, one of the technical problems of the embodiment is to provide a surface - emitting laser device capable of improving light output by improving the optical confinement efficiency around the light - emitting layer and a surface - emitting laser package including the surface - emitting laser device. [[ID=​​​​​​​​​​​​x When the layer of GaAs (0 < X < 1), the Al concentration in the second cavity 233 can be controlled to decrease in the direction of the active layer 232, and as shown in Figure 15 , the bandgap energy level of the second cavity 233 can be controlled to decrease in the direction of the active layer 232, so there is a technical effect that the light output can be improved by improving the optical confinement efficiency.

[0378] (Fourth Embodiment)

[0379] Next, Figure 16 is an exemplary view of the energy band diagram 204 in the surface-emitting laser device according to the fourth embodiment.

[0380] The fourth embodiment can adopt the technical features of the above first to third embodiments, and the main features of the fourth embodiment will be mainly described below.

[0381] The second width T2 of the second cavity 233 can be greater than the first width T1 of the first cavity 231 in the fourth embodiment.

[0382] For example, the second cavity 233 can be formed of a material of Al y Ga (1-y) As (0 < y < 1), but not limited thereto, and can include a single layer or multiple layers of Al y Ga (1-y) As.

[0383] For example, the second cavity 233 can include a second-first cavity layer 233a and a second-second cavity layer 233b. The second-second cavity layer 233b can be further separated from the active layer 232 than the second-first cavity layer 233a. The second-second cavity layer 233b can be formed to be thicker than the second-first cavity layer 233a, but not limited thereto. At this time, the second-second cavity layer 233b can be formed to have a thickness of about 60 to 70 nm, and the second-first cavity layer 233a can be formed to have a thickness of about 40 to 55 nm, but not limited thereto.

[0384] According to the fourth embodiment, the second width T2 of the second cavity 233 can be formed to be greater than the first width T1 of the first cavity 231, and the resonance efficiency can be improved, thereby improving the light output.

[0385] Next, Figure 17A and 17B is the doping concentration data in the first conductive first doped layer 261 of the active region of the surface-emitting laser device according to the fourth embodiment shown in Figure 16 .

[0386] For example, in Figure 17A and17B , the horizontal axis represents the doping concentration of the first conductive dopant in the first conductive first doping layer 261 as the distance from the active layer 232 increases in the direction of the first reflective layer 220 (direction X).

[0387] According to an embodiment, the concentration of the first conductive dopant in the first conductive first doping layer 261 can be controlled to increase from the direction of the active layer 232 in the direction of the first reflective layer 220, so that the increase in the doping concentration in the region adjacent to the active layer 232 is controlled to prevent a decrease in light intensity due to light absorption, and the doping concentration in the region adjacent to the first reflective layer 220 is increased to improve voltage efficiency due to resistance reduction, and thus there is a technical effect of being able to improve light output.

[0388] For example, reference Figure 17A When the first conductive first doping layer 261 includes the first-first doping layer 261a and the first-second doping layer 261b, as the doping concentration in the first-second doping layer 261b, which is arranged to be further separated from the active layer 232 than the first-first doping layer 261a, increases from d1 to d2 to d3, a decrease in light intensity due to light absorption in the first-first doping layer 261a adjacent to the active layer 232 can be prevented, and voltage efficiency according to a reduction in resistance in a region of the first-second doping layer 261b adjacent to the first reflective layer 220 can be improved and thus there is a technical effect of being able to improve light output.

[0389] In addition, reference Figure 17B When the first conductive-first doping layer 261 includes the first-first doping layer 261a, the first-second doping layer 261b and the first-third doping layer 261c, as the doping concentrations in the first-second doping layer 261b and the first-third doping layer 261c, which are further separated from the active layer 232 than the first-first doping layer 261a, increase to d1, d2 and d3 respectively, the reduction in light intensity due to light absorption in the area adjacent to the active layer 232 can be prevented, and the voltage efficiency according to the reduction in resistance in the area adjacent to the first reflective layer 220 can be improved, and thus there is a technical effect of being able to improve light output.

[0390] (Fifth embodiment)

[0391] Next, Figure 18 is an exemplary view of an energy band diagram 205 in the surface-emitting laser device according to the fifth embodiment.

[0392] According to the fifth embodiment, the active region 230 may include a second cavity 233 disposed between the second reflective layer 250 and the active layer 232 , and the second cavity 233 may be adjacent to the second reflective layer 250 and may include a second conductive-second doping layer 262 .

[0393] According to an embodiment, by including the second conductive-second doping layer 262 in a portion of the second cavity 233 and by reducing resistance compared to the existing active area, voltage efficiency can be improved by lowering resistance in the active area, and thus there is a technical effect of being able to improve light output.

[0394] For example, in an embodiment, when the second cavity 233 includes a second-first cavity layer 233a and a second-second cavity layer 233b, the second conductive-second doping layer 262 may be included in the second-second cavity layer 233b, which is further separated from the active layer 232. Compared to the prior art, this improves voltage efficiency by reducing resistance in the active region, thereby achieving a technical effect of improving light output. For example, in an embodiment in which the second cavity 233 is doped, the operating voltage Vf is reduced compared to the comparative example by reducing resistance in the active region, thereby achieving a technical effect of improving light efficiency or light output.

[0395] In an embodiment, the area of ​​the second conductive-second doping layer 262 is controlled to be 10% to 70% of the area of ​​the second cavity 233, thereby achieving the technical effect of improving voltage efficiency and light output by reducing the resistance of the active region. In this case, when the area of ​​the second conductive-second doping layer 262 exceeds 70% of the area of ​​the second cavity 233, light output may be reduced due to light absorption in the doped region, and when this area is less than 10%, the contribution of the resistance reduction effect may be low.

[0396] With reference to the third to fifth embodiments, the total area of ​​the first conductive-first doping layer 261 and the second conductive-second doping layer 262 may be controlled to be 20% to 70% of the entire area of ​​the active region 230. When the upper limit is exceeded, light output may be reduced due to light absorption by the doped region, and when the total area is lower than the lower limit, the contribution of the resistance reduction effect may be low.

[0397] In an embodiment, the concentration of the second conductive dopant in the second conductive-second doping layer 262 is controlled to be 1×10 17 Up to 8x10 17 (atoms / cm 3), and thus there is a technical effect of improving voltage efficiency and light output by reducing resistance in the active region. At this time, when the concentration of the second conductive dopant in the second conductive-second doping layer 262 exceeds its upper limit, light output may be reduced due to light absorption in the doped region, and when the concentration is less than its lower limit, the contribution of the resistance reduction effect may be low.

[0398] In addition, in an embodiment, the concentration of the second conductive dopant of the second conductive-second doping layer 262 can be controlled to be equal to or lower than the concentration of the second conductive dopant of the second reflective layer 250, so that light absorption of the doped region can be prevented and the voltage efficiency can be improved by reducing the resistance in the active region, thereby improving the light output.

[0399] For example, when the concentration of the second conductive dopant in the second conductive-second doping layer 262 is 7×10 17 Up to 3x10 18 (atoms / cm 3 ), the concentration of the second conductive dopant in the second conductive-second doping layer 262 is controlled to be 1×10 17 to 7×10 17 (atoms / cm 3 ), and thus there is a technical effect of improving voltage efficiency and light output by reducing resistance in the active region.

[0400] Next, Figure 19 is a perspective view of a mobile terminal to which a surface emitting laser package according to an embodiment is applied.

[0401] like Figure 19 As shown in FIG, a mobile terminal 1500 of an embodiment may include a camera module 1520, a flash module 1530, and an autofocus device 1510 provided on a rear side. Here, the autofocus device 1510 may include one of the surface emitting laser devices according to the above embodiments as a light emitting unit.

[0402] The flash module 1530 may include a light emitting element for emitting light therein. The flash module 1530 may be operated by a camera operation of the mobile terminal or a user's control.

[0403] The camera module 1520 may include an image capturing function and an auto focus function. For example, the camera module 1520 may include an auto focus function using an image.

[0404] The autofocus device 1510 may include an autofocus function using a laser. The autofocus device 1510 can be used under conditions where the autofocus function of the image using the camera module 1520 is degraded, for example, it can be used mainly in close-up or dark environments at a distance of 10 meters or less. The autofocus device 1510 may include a light emitting unit configured to include a surface-emitting laser device and a light receiving unit such as a photodiode, which is configured to convert light energy into electrical energy.

[0405] Any reference in this specification to "one embodiment," "an embodiment," "example embodiment," etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. The appearances of these phrases in various places in the specification are not necessarily all referring to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is understood that it is within the scope of those skilled in the art to implement such feature, structure, or characteristic in connection with other embodiments of the present invention.

[0406] Although the embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the present principles. More particularly, various changes and modifications are possible in the component parts and / or arrangements of the subject combination arrangement within the scope of the present disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and / or arrangements, alternative uses will also be apparent to those skilled in the art.

Claims

1. A surface emitting laser device comprising: a first reflective layer, the first reflective layer comprising a first conductive dopant; a second reflective layer, the second reflective layer comprising a second conductive dopant; as well as an active region, the active region being arranged between the first reflective layer and the second reflective layer, The active region includes a first cavity including a first conductive doping layer, a second cavity including a second conductive doping layer, and an active layer disposed between the first cavity and the second cavity. Wherein, the first cavity is adjacent to the first reflective layer, Among them, the first cavity includes a layer based on Al x GaAs, where 0 < X < 1, and the Al concentration in the first cavity is controlled to decrease in the direction of the active layer. wherein the second width of the second cavity is greater than the first width of the first cavity, wherein the first reflective layer includes a first-first layer and a first-second layer disposed on the first-first layer, the first-first layer has a first aluminum concentration, the first-second layer has a second aluminum concentration, and the second aluminum concentration is higher than the first aluminum concentration; and Wherein, the thickness of the first-second layer is greater than the thickness of the first-first layer.

2. The surface emitting laser device according to claim 1, wherein The second cavity comprises a layer based on Al x GaAs, where 0 < X < 1, and the aluminum concentration in the second cavity is controlled to decrease in the direction of the active layer.

3. The surface emitting laser device according to claim 1, wherein The first reflective layer includes a first-third layer disposed between the first-first layer and the first-second layer, the first to third layers having a third aluminum concentration, The third aluminum concentration changes from the first aluminum concentration to the second aluminum concentration.

4. The surface emitting laser device according to claim 2, in, The thickness of the first conductive doping layer is 70% or less of the thickness of the first cavity, wherein the thickness of the second conductive doping layer is 70% or less of the thickness of the second cavity, The total thickness of the first conductive doping layer and the second conductive doping layer is 20% to 70% of the entire thickness of the active region.

5. The surface emitting laser device according to claim 1, wherein The first conductive doping layer is an n-type doping layer.

6. The surface emitting laser device according to claim 1, wherein The second cavity is adjacent to the second reflective layer.

7. The surface emitting laser device according to claim 2, in, The first conductive doping concentration of the first conductive doping layer is lower than the doping concentration of the first conductive dopant of the first reflective layer.

8. The surface emitting laser device according to claim 7, in, The first cavity includes a first-first cavity in contact with the first reflective layer and a first-second cavity in contact with the active layer. The first conductive doping layer is only arranged in the first-first cavity. 9 . The surface emitting laser device of claim 8 , wherein the first-first cavity layer is thicker than the first-second cavity layer.

10. A light emitting device comprising: A surface emitting laser device according to any one of claims 1 to 9.

Images