Light-emitting device

Abstract

The present invention relates to a light-emitting device and, more specifically, to a vertical-cavity surface-emitting laser comprising an oxide layer. Disclosed is the light-emitting device comprising: a first mirror layer; a second mirror layer arranged on the first mirror layer; a cavity layer which is arranged between the first mirror layer and the second mirror layer and which generates light; and a mesa that exposes side surfaces of the cavity layer and the second mirror layer.

Description

Light-emitting device

[0001] The present invention relates to a light emitting device, and more particularly, to a vertical cavity surface emitting laser including an oxide layer.

[0002] A vertical-cavity surface-emitting laser (VCSEL) is a laser that emits a laser beam in a vertical direction from the substrate surface.

[0003] A typical VCSEL includes N-DBR / P-DBR layers and an active layer disposed between the N-DBR and P-DBR layers. Electrons and holes injected through the N-DBR and P-DBR layers generate light in the active layer, and the light resonated in the N-DBR and P-DBR layers can be amplified and emitted.

[0004] The current flowing vertically in a VCSEL needs to be confined to a small area, and methods utilizing etching and oxidation have been employed for this purpose. For example, the N-DBR / P-DBR layers and the active layer can be etched to form ring-shaped trenches, forming isolated posts. The trenches can then be used to form an oxide layer, allowing the current to be concentrated within a small aperture.

[0005] The purpose of the present invention is to provide a light-emitting device with low energy consumption, high reliability, and improved accuracy.

[0006] The problem to be solved by the present invention is to provide a light-emitting device capable of preventing a decrease in reliability due to cracks occurring in a semiconductor layer.

[0007] Another problem to be solved by the present invention is to provide a light-emitting device capable of improving light-emitting efficiency by allowing current to flow intensively in a light-emitting region.

[0008] Another problem to be solved by the present invention is to provide a light-emitting device that can prevent performance degradation and reliability degradation caused by foreign substances by increasing the penetration path of foreign substances.

[0009] Another problem to be solved by the present invention is to provide a light-emitting device capable of improving the straightness of light.

[0010] A light-emitting device according to one embodiment of the present invention may include a first mirror layer, a second mirror layer disposed on top of the first mirror layer, a cavity layer disposed between the first mirror layer and the second mirror layer and generating light, and a mesa exposing side surfaces of the second mirror layer and the cavity layer.

[0011] In one embodiment, the second mirror layer may include one or more oxide layers that form an aperture (AP) through which light generated in the cavity layer passes.

[0012] In one embodiment, the length of the oxide layer from the edge of the oxide layer to the cavity may have a value between 0.95 and 1.05 times the diameter of the cavity.

[0013] In one embodiment, the first mirror layer may include a plurality of sequentially and repeatedly stacked first and second refractive index layers.

[0014] In one embodiment, the cavity layer may include a first gap layer over the first mirror layer, an active layer over the first gap layer, and a second gap layer over the active layer.

[0015] In one embodiment, the second mirror layer may include a plurality of first and second refractive index layers sequentially and repeatedly stacked on top of the oxide layer.

[0016] In one embodiment, the second mirror layer may further include a lower spacing layer disposed below the oxide layer.

[0017] In one embodiment, the lower spacing layer may be provided in multiple numbers.

[0018] In one embodiment, the oxide layer may include a first oxide layer and a second oxide layer overlying the first oxide layer.

[0019] The length of the first oxide layer may be longer than the length of the second oxide layer.

[0020] In one embodiment, the thickness of the first oxide layer may be different from the thickness of the second oxide layer.

[0021] The second mirror layer may further include an upper spacing layer between the first oxide layer and the second oxide layer.

[0022] In one embodiment, the second mirror layer may further include a plurality of sub-oxide layers positioned on the outer surface of the second refractive index layer.

[0023] In one embodiment, the length of the sub-oxide layer from the edge of the sub-oxide layer to the boundary with the second refractive index layer may be shorter than the length of the oxide layer.

[0024] In one embodiment, the interface connecting the boundaries between the plurality of sub-oxidation layers and the second refractive index layer can form a curved surface.

[0025] In one embodiment, the device may include a first pad region electrically connected to the first mirror layer, and a second pad region at least partially disposed on the mesa and electrically connected to the second mirror layer.

[0026] In one embodiment, the second mirror layer may include one or more oxide layers that form a pupil through which light generated in the cavity layer passes.

[0027] In one embodiment, the second pad region may have an open portion exposing the upper region of the mesa.

[0028] In one embodiment, the open portion overlaps the pupil in a planar manner, and the diameter of the open portion may be larger than the diameter of the pupil.

[0029] In one embodiment, the second pad region may include a connection region forming the open portion and a connection region extending from the connection region.

[0030] In one embodiment, a concave groove may be formed on the upper surface of the connection area.

[0031] In one embodiment, the grooves are provided in plurality and can be concentric with the open portion.

[0032] In one embodiment, the method may further include a second electrode disposed on the mesa and electrically connected to the second mirror layer, and an insulating layer disposed on the mesa, exposing at least a portion of the second electrode.

[0033] In one embodiment, the insulating layer may include a plurality of sub-insulating layers.

[0034] In one embodiment, the thickness of the oxide layer may be thinner than the thickness of the first or second refractive index layer.

[0035] In one embodiment, the thickness of the first refractive index layer disposed on the uppermost portion of the second mirror layer may be at least twice the thickness of the other first refractive index layers.

[0036] In one embodiment, the thickness of the oxide layer may have a value in the range of 0.3 to 0.4 times the thickness of the first or second refractive index layer.

[0037] According to an embodiment of the present invention, a light emitting device may include a semiconductor layer, an insulating layer, and a conductive layer. The semiconductor layer may include a first mirror layer, an active layer disposed on the first mirror layer, an oxide layer disposed on the active layer, and a second mirror layer disposed on the oxide layer. The insulating layer may cover the semiconductor layer and include a first opening exposing the first mirror layer and a second opening exposing the second mirror layer. The conductive layer may include a first conductive layer formed on the insulating layer and electrically connected to the first mirror layer, and a second conductive layer disposed spaced apart from the first conductive layer and electrically connected to the second mirror layer. The semiconductor layer may include a multi-stage groove structured by a first groove formed in the second mirror layer and a second groove formed inside the first groove. In addition, the second groove may penetrate the second mirror layer, the active layer, and the oxide layer to expose the first mirror layer.

[0038] The first opening of the insulating layer can expose the first mirror layer in the second groove. The first conductive layer can be connected to the first mirror layer through the first opening of the insulating layer in the second groove.

[0039] The first conductive layer may include a first connection region, a first pad region, and a first connection region. The first connection region may be connected to the first mirror layer and may have a ring shape with a portion of the connection region open. The first pad region may be located outside the first connection region and may be electrically connected to the external component. In addition, the first connection region may be located outside the first connection region and may connect the first connection region and the first pad region.

[0040] The second conductive layer may include a second connection region, a second pad region, and a second connection region. The second connection region may be located on the inner side of the first connection region, may be connected to the second mirror layer, and may include a hole exposing an exit surface that emits light. The second pad region may be located on the outer side of the first connection region and may be electrically connected to the external component. In addition, the second connection region may connect the second connection region and the second pad region through an open region of the first connection region.

[0041] The insulating layer may be positioned below the second connection area and may include a protective area in which the second opening is formed.

[0042] The inner side of the protection area forming the second opening may be located between the inner side wall and the outer side wall of the second connection area of ​​the second conductive layer.

[0043] The inner surface of the protection area forming the second opening may include a first inclined surface having different inclination angles and a second inclined surface positioned below the first inclined surface.

[0044] The inclination angle of the first inclined surface with respect to the upper surface of the second mirror layer may be greater than the inclination angle of the second inclined surface.

[0045] The height of the second inclined surface may be 0.5 times or less than the height of the first inclined surface.

[0046] The above protection area may include a first area having a flat upper surface, a second area having the first inclined surface, and a third area having the second inclined surface. The first area, the second area, and the third area may be sequentially arranged. In addition, the width of the first area may be greater than the width of the second area and the width of the third area.

[0047] The inner surface of the second connection area forming the hole of the second connection area of ​​the second conductive layer may have a multi-stage structure.

[0048] The inner side of the second connection region may include a first inner side and a second inner side located below the first inner side. In addition, the first inner side and the second inner side may have different inclination angles with respect to the upper surface of the second mirror layer.

[0049] The first inner side of the second connection area may have a greater inclination angle than the second inner side.

[0050] The inner surface of the first connection area may include a first upper surface and a second upper surface positioned between the first inner surface and the second inner surface. In addition, the width of the first upper surface may be smaller than the width of the second upper surface.

[0051] In one embodiment, the second connection area may be in the form of a ring with some areas open.

[0052] In another embodiment, the second connection area may be circular in shape without an open area.

[0053] According to another embodiment, the second connection area may have the same width from one end connected to the second connection area to the other end connected to the second pad area.

[0054] According to another embodiment, the second connection area may have a width that increases from one end connected to the second connection area to the other end connected to the second pad area.

[0055] According to another embodiment, the second connection area may include a 2-1 connection area connected to the second connection area and a 2-2 connection area connected to the second pad area. In this case, the 2-1 connection area may have the same width from one end connected to the second connection area to the other end connected to the 2-2 connection area. In addition, the 2-2 connection area may have an increasing width from one end connected to the 2-1 connection area to the other end connected to the second pad area.

[0056] According to another embodiment, the second connection area may include a second-first connection area connected to the second connection area and a second-second connection area connected to the second pad area. In this case, the second-second connection area may be formed to have a predetermined angle with the second-first connection area.

[0057] The first pad region may be positioned adjacent to one edge connected to one side of the semiconductor layer. In addition, the second pad region may be positioned adjacent to the other edge connected to one side of the semiconductor layer.

[0058] The separation distance between the first pad area and the second pad area may be smaller than the width of the first pad area and the width of the second pad area.

[0059] The length from one end of the second connection area connected to the second connection area to the other end of the second connection area connected to the second pad area may be smaller than the width of the second pad area.

[0060] The present invention can provide a light-emitting device with low energy consumption, high reliability, and improved accuracy.

[0061] A light-emitting device according to an embodiment of the present invention can prevent reliability degradation due to cracks in the semiconductor layer by covering a portion of the area between the semiconductor layer and the conductive layer with an insulating layer.

[0062] A light-emitting device according to an embodiment of the present invention can improve light-emitting efficiency by covering a portion of a region between a semiconductor layer and a conductive layer with an insulating layer to allow current to flow intensively in the light-emitting region.

[0063] A light-emitting device according to an embodiment of the present invention can prevent performance degradation and reliability degradation caused by foreign substances by covering a portion of a region between a semiconductor layer and a conductive layer with an insulating layer to increase a penetration path of foreign substances.

[0064] A light-emitting device according to an embodiment of the present invention can improve the straightness of light by reflecting light through a sloped surface of a conductive layer.

[0065] FIG. 1 is a top view showing a light-emitting device according to a first embodiment of the present invention.

[0066] FIG. 2 is a cross-sectional view showing each layer constituting a light-emitting device according to the first embodiment of the present invention.

[0067] Figure 3 is an enlarged view showing D of Figure 2.

[0068] Fig. 4 is a cross-sectional view showing the II' direction cross-section of Fig. 1.

[0069] Figure 5 is an enlarged view showing a portion of Figure 4.

[0070] Figure 6 is an enlarged view showing a portion of the upper surface of Figure 4.

[0071] Figure 7 is a cross-sectional view taken along the line Ⅱ-Ⅱ' of Figure 1.

[0072] Figure 8 is a plan view of a light emitting device according to a second embodiment of the present invention.

[0073] Fig. 9 is a cross-sectional view (A1-A2) of the light emitting device of Fig. 8.

[0074] Fig. 10 is another cross-sectional view (A3-A4) of a light-emitting device according to the second embodiment.

[0075] Fig. 11 is an enlarged view of one area (A5 in Fig. 10) of a light-emitting device according to the second embodiment.

[0076] Fig. 12 is a plan view for explaining the conductive layer structure of a light-emitting device according to the third embodiment.

[0077] Fig. 13 is a plan view for explaining the conductive layer structure of a light-emitting device according to the fourth embodiment.

[0078] Fig. 14 is a plan view for explaining the conductive layer structure of a light-emitting device according to the fifth embodiment.

[0079] Fig. 15 is a plan view for explaining the conductive layer structure of a light-emitting device according to the sixth embodiment.

[0080] In the following description, for purposes of explanation, numerous specific details are set forth to provide a thorough understanding of various embodiments or implementations of the present disclosure. As used herein, the terms "embodiment" and "implementation" are interchangeable to refer to non-limiting examples of devices or methods that utilize one or more of the inventive concepts disclosed herein. However, it will be apparent that various embodiments may be practiced without utilizing these specific details or using one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form to avoid unnecessarily obscuring the various embodiments. Furthermore, while the various embodiments may vary from one another, they are not necessarily exclusive. For example, specific features, configurations, and characteristics of an embodiment may be utilized or implemented in other embodiments without departing from the scope of the inventive concepts.

[0081] Unless otherwise specified, the illustrated embodiments should be understood to provide exemplary features of varying details of some ways in which the concepts of the present invention may be practically implemented. Therefore, unless otherwise specified, the features, components, modules, layers, membranes, panels, regions, and / or aspects (hereinafter, individually or collectively referred to as "elements") of the various embodiments may be differently combined, separated, interchanged, and / or rearranged without departing from the scope of the concepts of the present invention.

[0082] The use of cross-hatching and / or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, the presence or absence of cross-hatching or shading, unless expressly stated, does not imply or indicate any preference or requirement for any particular material, material properties, dimensions, proportions, commonality between the illustrated elements, and / or any other features, properties, or characteristics of the elements. Furthermore, in the accompanying drawings, the dimensions and relative sizes of elements may be exaggerated for clarity and / or illustrative purposes. When embodiments are implemented differently, certain process sequences may be performed differently from the illustrated sequence. For example, two consecutively illustrated processes may be performed substantially simultaneously or in a reverse order from the illustrated sequence. Furthermore, like reference numerals designate like elements.

[0083] When an element, such as a layer, is referred to as being "on," "connected to," or "joined to" another element or layer, the element may be directly on, connected to, or joined to the other element or layer, or there may be intervening elements or layers present. However, when an element or layer is referred to as being "directly on," "directly connected to," or "directly joined to" another element or layer, there are no intervening elements or layers present. For this purpose, the term "connected" may refer to physical, electrical, and / or fluidic connections, with or without intervening elements. Furthermore, the DR1-axis, DR2-axis, and DR3-axis are not limited to the three axes of a Cartesian coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the DR1-axis, DR2-axis, and DR3-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For purposes of this disclosure, “one or more of X, Y or Z” and “one or more selected from the group consisting of X, Y or Z” may be interpreted as only X, only Y, only Z or any combination of two or more of X, Y and Z, such as, for example, XYZ, XYY, YZ and ZZ. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0084] Although the terms "first," "second," and the like may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. Therefore, the first element discussed below may be referred to as the second element without departing from the teachings of the present disclosure.

[0085] Spatially relative terms such as "beneath," "beneath," "directly beneath," "lower," "above," "upper," "above," "higher than," "side" (as in, for example, a "side wall"), and the like may be used for descriptive purposes and thereby to describe the relationship of one element to other element(s) as depicted in the drawings. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture in addition to the orientations depicted in the drawings. For example, if the device in the drawings were turned over, an element described as "beneath" or "beneath" another element or feature would then be oriented "above" the other element or feature. Therefore, the exemplary term "beneath" can encompass both orientations above and below. Furthermore, the device can be oriented differently (e.g., rotated 90° or oriented in other orientations), and thus the spatially relative descriptors used herein can also be interpreted accordingly.

[0086] The terminology used herein is for the purpose of describing particular embodiments and is not limiting. The singular forms "a," "an," and "the" as used herein also include the plural forms unless the context clearly dictates otherwise. Furthermore, the terms "comprises," "comprising," "includes," and / or "comprising" as used herein specify the presence of stated features, integers, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Furthermore, the terms "substantially," "about," and other similar terms as used herein are used as terms of approximation rather than degrees, and as such, are used to describe inherent deviations from measured, calculated, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0087] Various embodiments are described below with reference to cross-sectional and / or exploded illustrations, which are schematic illustrations of idealized embodiments and / or intermediate structures. As such, variations from the shapes of the illustrated drawings may be expected, for example, as a result of manufacturing techniques and / or tolerances. Therefore, the embodiments disclosed herein should not necessarily be construed as limited to the shapes of specific illustrated regions, but should be construed to include, for example, deviations in shape resulting from manufacturing. In this way, the regions depicted in the drawings may be schematic in nature, and the shapes of these regions may not reflect the actual shapes of regions of the device, and as such, are not necessarily intended to have a limiting meaning.

[0088] As is conventional in the art, some embodiments may be illustrated and described in the accompanying drawings in terms of functional blocks, units, and / or modules. Those skilled in the art will appreciate that these blocks, units, and / or modules are physically implemented by electronic (or optical) circuits such as logic circuits, discrete components, microprocessors, wiring circuits, memory elements, and wiring connections formed using semiconductor-based or other manufacturing techniques. When the blocks, units, and / or modules are implemented by microprocessors or other similar hardware, they may be programmed and controlled using software (e.g., microcode) to perform the various functions discussed herein, and optionally, may be driven by firmware and / or software. Furthermore, each block, unit, and / or module may be implemented by dedicated hardware, or by a combination of dedicated hardware for performing some functions and processors (e.g., one or more programmed processors and associated circuitry) for performing other functions. Additionally, the blocks, units, and / or modules of some embodiments may be physically separated into two or more interacting and individual blocks, units, and / or modules without departing from the scope of the present invention. Additionally, the blocks, units, and / or modules of some embodiments may be physically combined into more complex blocks, units, and / or modules without departing from the scope of the present invention.

[0089] Unless otherwise defined, all terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries, such as terms defined in commonly used dictionaries, should be interpreted to have a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an idealistic or overly formal sense unless explicitly defined herein.

[0090] The present invention discloses a light emitting device (1001) including a first mirror layer (110), a second mirror layer (120) disposed on the first mirror layer (110), a cavity layer (130) disposed between the first mirror layer (110) and the second mirror layer (120) and generating light, and a mesa (M) exposing side surfaces of the second mirror layer (120) and the cavity layer (130).

[0091] The above light-emitting device (1001) may be a vertical cavity surface-emitting laser (VCSEL), which may be a semiconductor laser diode. Fig. 1 is a top view of a light-emitting device (1001) according to a first embodiment of the present invention, wherein light may be emitted through an open portion (OP) on the top surface. The shape of the light-emitting device (1001) of Fig. 1 is exemplary, and the present invention is not limited thereto.

[0092] The above first mirror layer (110) may be a distributed Bragg reflector composed of multiple layers, and may be a reflective layer configured so that light generated in the cavity layer (130) described below can be reflected repeatedly through each layer and gain an advantage.

[0093] For example, the first mirror layer (110) may include a plurality of sequentially and repeatedly laminated first and second refractive index layers (112, 114).

[0094] The first refractive index layer (112) may have a first refractive index, and the second refractive index layer (114) may have a second refractive index that is different from the first refractive index. Fresnel reflection may occur at the interface due to the difference in refractive indices between the first refractive index layer (112) and the second refractive index layer (114). The sequentially stacked first refractive index layer (112) and second refractive index layer (114) may form one pair, and the first mirror layer (110) may include a plurality of pairs. For example, the first mirror layer (110) may include 39 pairs.

[0095] The first refractive index layer (112) and the second refractive index layer (114) may have various thicknesses, for example, values ​​between 60 nm and 70 nm.

[0096] As an example, the first refractive index layer (112) may be a GaAs layer having a relatively high refractive index, and the second refractive index layer (114) may be an AlGaAs layer having a relatively low refractive index.

[0097] The thickness (T1) of the first mirror layer (110) may have various values, for example, may have a value between 4.5 μm and 5.5 μm.

[0098] The first mirror layer (110) may be doped as n-type by including one or more impurities such as Si, C, Ge, Sn, Te, Pb, etc. That is, the first mirror layer (110) may be an n-type mirror layer.

[0099] The second mirror layer (120) may be a mirror layer disposed on the first mirror layer (110). The second mirror layer (120) may be a distributed Bragg reflector composed of multiple layers, and may be a reflective layer configured so that light generated in the cavity layer (130) described below can be reflected repeatedly through each layer and gain an advantage. The light generated in the cavity layer (130) can be amplified and emitted by being reflected repeatedly between the first mirror layer (110) and the second mirror layer (120).

[0100] For example, the second mirror layer (120) may include a plurality of sequentially and repeatedly laminated first and second refractive index layers (122, 124).

[0101] The first refractive index layer (122) may have a first refractive index, and the second refractive index layer (124) may have a second refractive index that is different from the first refractive index. Fresnel reflection may occur at the interface due to the difference in refractive indices between the first refractive index layer (122) and the second refractive index layer (124). The sequentially stacked first refractive index layer (122) and second refractive index layer (124) may form one pair, and the second mirror layer (120) may include a plurality of pairs. For example, the second mirror layer (110) may include 24 pairs.

[0102] The first refractive index layer (122) and the second refractive index layer (124) may have various thicknesses (T7, T8), for example, values ​​between 60 nm and 70 nm.

[0103] Referring to FIG. 5, the thickness (T6) of the first refractive index layer (122) disposed on the uppermost portion of the second mirror layer (120) may be at least twice the thickness (T7) of the other first refractive index layers (122). For example, the thickness (T6) of the first refractive index layer (122) disposed on the uppermost portion may have a value of 170 nm to 180 nm.

[0104] As an example, the first refractive index layer (122) may be a GaAs layer having a relatively high refractive index, and the second refractive index layer (124) may be an AlGaAs layer having a relatively low refractive index.

[0105] The thickness (T2) of the second mirror layer (120) may have various values, for example, may have a value between 3 μm and 4 μm.

[0106] The second mirror layer (120) may be doped with a conductivity type opposite to that of the first mirror layer (110). For example, the second mirror layer (120) may be doped with a p-type by including an impurity such as Mg. That is, the second mirror layer (110) may be a p-type mirror layer.

[0107] The cavity layer (130) is a layer that generates light and is disposed between the first mirror layer (110) and the second mirror layer (120), and may include an active layer (132, 134).

[0108] The above active layer (132, 134) is a light-emitting layer formed on top of the first mirror layer (110), and may include a phosphide or nitride semiconductor such as (Al, Ga, In)P or (Al, Ga, In)N, and may be grown on the first mirror layer (110) using a technique such as MOCVD, MBE, or HVPE.

[0109] Additionally, the active layer (132, 134) may include a quantum well structure (QW) including at least two barrier layers (132) and at least one well layer (134), and further, may include a multiple quantum well structure (MQW) including a plurality of barrier layers (132) and a plurality of well layers (134).

[0110] The wavelength of light emitted from the above active layer (132, 134) can be controlled by controlling the composition ratio of the material constituting the well layer (134). In this case, the well layer (134) may commonly include the same element and may include In.

[0111] The above well layer (134) is located between the barrier layers (132), and the band gap energy of the well layer (134) is smaller than the band gap energy of the barrier layer (132).

[0112] The above well layer (132) is In x Ga (1-x) It can contain or be formed of As(0<x<1), and the wavelength of the light emitted can be controlled depending on the composition ratio (x) of In.

[0113] The above barrier layer (134) is made of Al x Ga (1-x) As(0<x<1) or can be formed by this

[0114] The above barrier layer (132) and well layer (134) are alternately laminated, and it is preferable that they are alternately laminated at least twice. Adjacent barrier layers (132) and well layers (134) can form a pair. For example, the active layers (132, 134) can include three pairs.

[0115] The thickness of the above barrier layer (132) and well layer (134) can be configured in various ways.

[0116] The first barrier layer (132) and the last barrier layer (132) of the active layer (132, 134) may have a thickness thicker than the other barrier layers (132). For example, the thickness of the first barrier layer (132) may be 5.5 nm to 6 nm, the thickness of the last barrier layer (132) may be 8.2 nm to 9 nm, and the other barrier layers (132) may be formed to have a thickness thinner than the first barrier layer (132) and thicker than the other barrier layers (132), for example, may be formed to have a thickness of 7.8 nm to 8 nm.

[0117] In addition, the cavity layer (130) may further include a first spacing layer (136) and a second spacing layer (138). The first spacing layer (136) is a layer disposed on the first mirror layer (110) and may be positioned between the first mirror layer (110) and the active layer (132, 134). The second spacing layer (138) is a layer disposed on the active layer (132, 134) and may be positioned between the active layer (132, 134) and the second mirror layer (120).

[0118] The thickness of the first gap layer (136) and the second gap layer (138) may have a value between 0.7 and 0.75 times the total thickness of the active layer (132, 134).

[0119] Meanwhile, the light emitting device (1001) may include a mesa (M) exposing the side surfaces of the second mirror layer (120) and the cavity layer (130), as illustrated in FIG. 4. The mesa (M) may be a hill structure formed by etching the second mirror layer (120) and the cavity layer (130) so that the upper surface of the first mirror layer (110) is exposed. The side surface of the mesa (M) may form a slope.

[0120] Since the second mirror layer (120) is exposed through the side surface of the mesa (M), the second mirror layer (120) may further include an oxide layer (200) formed through an oxidation process.

[0121] The above oxide layer (200) is a layer formed by oxidation of a portion of the second mirror layer (120), and can have various configurations. The oxide layer (200) can be formed by wet oxidation of the second mirror layer (120), and can be formed by partial oxidation of a region of the second mirror layer (120) having a high Al content. Accordingly, the oxide layer (200) can be formed by gradually oxidizing from the side surface of the mesa (M) and the side surface of the second mirror layer (120) toward the center of the mesa (M).

[0122] The above oxide layer (200) is a layer formed within the mesa (M), and the edge side of the oxide layer (200) can be exposed through the side of the mesa (M).

[0123] The above oxide layer (200) can form a pupil (AP, aperture) through which light generated in the cavity layer (130) passes.

[0124] Referring to Fig. 4, the pupil (AP) may be a circular opening having a diameter (D2). The diameter (D2) is the distance between the two sides of the pupil (AP) and the horizontal straight line passing through the center (CT) of the pupil (AP), and may be defined as the distance between the vertical lines (L3, L4) passing through the two sides of the pupil (AP) in Fig. 4. The diameter (D2) may have various values.

[0125] The length (D3, D4) of the oxide layer (200) from the edge of the oxide layer (200) to the cavity (AP) may have a value between 0.95 and 1.05 times the diameter (D2) of the cavity (AP).

[0126] In Fig. 4, the length (D3, D4) of the oxide layer (200) from the edge of the oxide layer (200) to the cavity (AP) can be defined as the length from the vertical line (E) passing through the edge of the oxide layer (200) to the vertical line (L3 or L4) passing through the boundary of the cavity (AP). The length D3 from E to L3 can be the same as the length D4 from E to L4. For example, the ratio D3:D2:D4 of D3, D2, and D4 can be 1:1:1.

[0127] Referring to FIGS. 4 and 6, the length K, which is the sum of D3, D2, and D4, may correspond to the entire diameter of the oxide layer (200) and may be 18 μm. At this time, the diameter (D2) of the pore (AP) may be 5.7 μm to 6.3 μm, and more preferably, 6 μm.

[0128] The center of the oxide layer (200) on the plane and the center of the cavity (AP) can coincide with CT.

[0129] The above oxide layer (200) can be formed with various thicknesses (T4). For example, the thickness (T4) of the oxide layer (200) can be formed to a thickness thinner than the thicknesses (T7, T8) of the first and second refractive index layers (122, 124) of the above-described second mirror layer (120). Specifically, the thickness (T4) of the oxide layer (200) can have a value in the range of 0.3 to 0.4 times the thickness (T7, T8) of the first or second refractive index layer (122, 124).

[0130] Meanwhile, the oxide layer (200) may be placed directly on top of the cavity layer (130), but is not limited thereto. That is, the second mirror layer (120) may further include a lower spacing layer (129) placed below the oxide layer (200).

[0131] The lower gap layer (129) is a layer placed between the oxide layer (200) and the cavity layer (130), and can be formed into a double-layer structure in which first and second spacers (129a, 129b) having different compositions are sequentially stacked to form a pair.

[0132] The lower spacing layer (129) may be provided in multiples. As illustrated in FIG. 3, the lower spacing layer (129) may include two pairs, and may include first spacers (129a1, 129a2) and second spacers (129b1, 129b2) that are repeatedly and sequentially stacked.

[0133] The above oxide layer (200) is not limited to a single layer structure and may be composed of multiple multi-layer structures spaced apart from each other.

[0134] For example, the oxide layer (200) may include a first oxide layer (210) and a second oxide layer (220) on top of the first oxide layer (210). At this time, an opening formed in the oxide layer located at the lowest position, i.e., the first oxide layer (210), is defined as a pore (AP).

[0135] Since the above first oxide layer (210) can be configured identically or similarly to the above-described oxide layer (200), description of the overlapping configuration is omitted.

[0136] The second oxide layer (220) is an oxide layer formed on top of the first oxide layer (210), and may be formed by partially oxidizing an area with a high Al content among the second mirror layer (120) exposed through the side surface of the mesa (M).

[0137] The second oxide layer (220) is a layer formed within the mesa (M), and the edge side of the second oxide layer (220) can be exposed through the side of the mesa (M).

[0138] Referring to Fig. 4, an opening is formed in the central portion of the second oxide layer (220), and the opening may be a circular opening concentric with the pore (AP) of the first oxide layer (210). The opening may have a larger diameter than the pore (AP).

[0139] The length (D5, D6) of the second oxide layer (220) from the edge of the second oxide layer (220) to the opening may be different from the length (D3, D4) of the first oxide layer (210) from the edge of the first oxide layer (210) to the aperture (AP).

[0140] In Fig. 4, the length (D5, D6) of the second oxide layer (220) from the edge of the second oxide layer (210) to the opening may be defined as the length from a vertical line passing through the edge of the second oxide layer (220) to a vertical line (L5 or L6) passing through the boundary of the opening. D5 may be the same as D6.

[0141] For example, the length (D3, D4) of the first oxide layer (210) may be longer than the length (D5, D6) of the second oxide layer (220).

[0142] The second oxide layer (220) may be formed with various thicknesses (T5). For example, the thickness (T4) of the first oxide layer (210) may be different from the thickness (T5) of the second oxide layer (220). Specifically, the thickness (T4) of the first oxide layer (210) may be formed to be thicker than the thickness (T5) of the second oxide layer (220).

[0143] At this time, the second mirror layer (120) may further include an upper spacing layer (127) between the first oxide layer (210) and the second oxide layer (220).

[0144] The upper spacing layer (127) is a layer disposed between the first oxide layer (210) and the second oxide layer (220), and may be formed as a double-layer structure in which first and second spacers (127a, 127b) having different compositions are sequentially laminated to form a pair. The upper spacing layer (127) may be provided in multiple numbers.

[0145] Additionally, the second mirror layer (120) may further include a plurality of sub-oxide layers (230) positioned on the outer side of the second refractive index layer (124).

[0146] The second refractive index layer (124) is a layer having a relatively higher Al content than the first refractive index layer (122), and the sub-oxidation layer (230) can be formed by oxidizing the outer region of the second refractive index layer (124).

[0147] As the second refractive index layers (124) are provided in multiple numbers, the sub-oxidation layers (230) can also be provided in multiple numbers.

[0148] Referring to FIG. 5, the length (D7) of the sub-oxide layer (230) from the edge of the sub-oxide layer (230) to the boundary with the second refractive index layer (124) may be shorter than the lengths (D3, D4) of the oxide layers (200, 210).

[0149] At this time, a boundary surface (BL) connecting the boundary between the plurality of sub-oxidation layers (230) and the second refractive index layer (124) may be formed. The boundary surface (BL) may be configured as a plane or a curved surface (concave or convex). The boundary surface (BL) may also include a region in which the curvature is variable.

[0150] Meanwhile, referring to FIG. 1 and FIG. 4, the first pad region (170) may be electrically connected to the first mirror layer (110), and a second pad region (180) may be electrically connected to the second mirror layer (120) by having at least a portion disposed on the mesa (M).

[0151] The first pad region (170) may be a pad region connected to a first electrode connected to the first mirror layer (110). The second pad region (180) may be a pad region connected to a second electrode (140) disposed on the upper surface of the second mirror layer (120). Here, the second electrode (140) is an electrode disposed on the upper portion of the mesa (M) and electrically connected to the second mirror layer (120), and power may be applied through the first pad region (170) and the second pad region (180) to generate light in the active layer (132, 134).

[0152] At this time, the light emitting device (1001) may further include an insulating layer (150) disposed between the second pad region (180) and the mesa (M). The insulating layer (150) exposes at least a portion of the second electrode (140) and at least a portion of the insulating layer may be disposed on the mesa (M).

[0153] A portion of the insulating layer (150) on the mesa (M) may be etched to expose the second electrode (140). The second pad region (180) may be connected to the second electrode (140) exposed by etching the insulating layer (150).

[0154] The above insulating layer (150) may be formed as a single layer or multi-layer structure. For example, the insulating layer (150) may include a plurality of sub-insulating layers (152, 154, 156). For example, the insulating layer (150) may include a first sub-insulating layer (152) and a second sub-insulating layer (154) on the upper side of the first sub-insulating layer (152). As another example, a third sub-insulating layer (156) may be further disposed on at least a portion between the first sub-insulating layer (152) and the second sub-insulating layer (154). The first to third sub-insulating layers (152, 154, 156) may be formed of different materials and thicknesses.

[0155] FIG. 4 illustrates an example in which the insulating layer (150) includes first and third sub-insulating layers (152, 156), and FIG. 5 illustrates an example in which the insulating layer (150) includes first and second sub-insulating layers (152, 154), but it is to be understood that a greater number of sub-insulating layers may be included.

[0156] The second pad area (180) may include a connection area (182) at least partially disposed on the upper portion of the mesa (M) as a finger-shaped electrode pad and a connection area (184) extending from the connection area (182).

[0157] At this time, the second pad area (180) may have an open portion (OP) that exposes the upper area of ​​the mesa (M). Light may be emitted through the open portion (OP). The open portion (OP) may be a circular opening, but is not limited thereto. The open portion (OP) may be formed in the connection area (182). The connection area (182) may be formed in various shapes, and as an example, may be formed in a ring shape as illustrated in FIG. 1, but is not limited thereto.

[0158] As illustrated in Fig. 4, the open portion (OP) may overlap the pupil (AP) on a plane. The center of the open portion (OP) may coincide with the center (CT) of the pupil (AP).

[0159] The diameter (D1) of the above open portion (OP) may be larger than the diameter (D2) of the above cavity (AP). That is, the inner edge boundaries (L1, L2) of the connection area (182) forming the open portion (OP) of the connection area (182) may be positioned further outward than the inner edge boundaries (L3, L4) of the oxide layer (200) forming the above cavity (AP).

[0160] Meanwhile, a concave groove (G) may be formed on the upper surface of the connection area (182). The groove (G) may be a concave groove concentric with the open portion (OP). In addition, the groove (G) may be provided in multiple numbers, and the plurality of grooves (G) may be concentric with the open portion (OP). The depth, width, and curvature of each groove (G) may be different from each other.

[0161] Meanwhile, the light-emitting device (1001) may further include a conductive semiconductor layer (115) doped with the same conductive type as the first mirror layer (110) at the lower portion of the first mirror layer (110). In addition, the light-emitting device (1001) may further include a growth substrate (S) on which the conductive semiconductor layer (115) is grown at the lowermost portion.

[0162] Meanwhile, the first pad region (170) may be formed in various shapes as an electrode pad electrically connected to the conductive semiconductor layer (115). For example, the first pad region (170) may be formed in a shape that surrounds at least a portion of the connection region (182) of the second pad region (180).

[0163] At this time, in order to electrically connect the first pad region (170) and the conductive semiconductor layer (115), an exposure groove (F) may be formed on the upper surface of the light emitting device (1001) to form an exposure region that exposes the conductive semiconductor layer (115). Fig. 7 is a cross-sectional view taken along line II-II' of Fig. 1, showing an exposure region where the first mirror layer (110) is exposed by the exposure groove (F). The exposure groove (F) may surround at least a portion of the connection region (182).

[0164] The above exposure groove (F) may extend to the lower portion of the first mirror layer (110) to expose the conductive semiconductor layer (115). A portion of the exposure groove (F) may extend to the outer side of the light-emitting device (1001).

[0165] Referring to FIG. 7, the exposed groove (F) may include a first inclined surface (S1) that starts from the upper surface of the exposed conductive semiconductor layer (115) and forms a side wall of the first mirror layer (110) and extends upward, and a second inclined surface (S2) that forms a side wall of the second mirror layer (120) and extends upward to the upper surface of the second mirror layer (120). The lower portion of the first inclined surface (S1) may include a side surface of the conductive semiconductor layer (115).

[0166] As seen in the cross-section of Fig. 7, the first inclined plane (S1) may be formed as a pair on both sides based on the exposed groove (F), and the second inclined plane (S2) may also be formed as a pair on both sides based on the exposed groove (F). The width between the pair of first inclined planes (S1) may narrow from top to bottom, and the width between the pair of second inclined planes (S2) may also narrow from top to bottom.

[0167] The first inclined surface (S1) and the second inclined surface (S2) may be connected. For example, the exposed groove may further include a third inclined surface (S3) connecting the first inclined surface (S2) and the second inclined surface (S3).

[0168] The depth (DP1) of the first inclined surface (S1) may be deeper than the depth (DP2) of the second inclined surface (S2). The uppermost width (W1) of the first inclined surface (S1) may be narrower than the uppermost width (W2) of the second inclined surface (S2). That is, the exposure groove (F) may be formed in a shape that becomes narrower from the top to the bottom.

[0169] Additionally, when viewed in the cross-section of Fig. 7, the size of the space surrounded by the second inclined surface (S2) may be larger than the size of the space surrounded by the first inclined surface (S1).

[0170] The slope of the first slope (S1) may be greater than the slope of the second slope (S2). That is, the first slope (S1) may be formed to be steeper than the second slope (S2).

[0171] The third inclined plane (S3) is a sub-incline connecting the first inclined plane (S1) and the second inclined plane (S2), and is formed with a gentler slope than the first inclined plane (S1) and the second inclined plane (S2), so that the first pad area (170) can be stably extended along the second inclined plane (S2) and the first inclined plane (S1).

[0172] The above-described insulating layer (150) can cover the first inclined surface (S1), the second inclined surface (S2), and the third inclined surface (S3), and can also cover the upper surface of the conductive semiconductor layer (115) exposed by the exposure groove (F). FIG. 7 illustrates an example in which the insulating layer (150) includes first and second sub-insulating layers (152, 154), but various shapes and numbers of insulating layers (150) are possible, and the present invention is not limited to the structure of FIG. 7. For example, the insulating layer (150) may further include an additional sub-insulating layer (156) between the first and second sub-insulating layers (152, 154).

[0173] The upper surface of the conductive semiconductor layer (115) positioned between the pair of first inclined surfaces (S1) can form a contact area electrically connected to the first pad area (170).

[0174] The above sub-insulating layer (152) can cover the contact area, and an opening can be formed in the sub-insulating layer (152) to expose a portion of the upper surface of the conductive semiconductor layer (115). The exposed area of ​​the contact area exposed by the opening of the sub-insulating layer (152) can contact the first pad area (170), and accordingly, the first pad area (170) can be electrically connected to the conductive semiconductor layer (115) through the contact area.

[0175] Meanwhile, the light emitting device (1001) may additionally include an ohmic electrode (190) covering the contact area exposed by the sub-insulating layer (152). That is, the ohmic electrode (190) may be placed on the contact area between a pair of first inclined surfaces (S1).

[0176] Among the above contact areas, a groove portion that is sunken downwards may be formed in the exposed area exposed by the sub-insulating layer (152). The groove portion is a groove formed in the conductive semiconductor layer (115), and since the ohmic electrode (190) fills the empty space formed by the groove portion, the surface area where the conductive semiconductor layer (115) and the ohmic electrode (190) come into contact with each other is increased by the groove portion, and as a result, the area where the conductive semiconductor layer (115) and the ohmic electrode (190) come into contact with each other may be increased. Here, the ohmic electrode (190) is not an essential component and may be omitted. When the ohmic electrode (190) is omitted, the empty space formed by the groove portion may be filled by the first pad area (170).

[0177] Meanwhile, the light emitting device (1001) may further include an additional pad region (HP). Referring to FIG. 1, when viewed from the top, the additional pad region (HP) may have a different shape from the first pad region (170) and the second pad region (180). The additional pad region (HP) may be formed of the same material as the first pad region (170) or the second pad region (180). The additional pad region (HP) may be arranged to be vertically spaced apart from the conductive semiconductor layer (115) and may be electrically insulated from the conductive semiconductor layer (115) or the second mirror layer (120). The additional pad region (HP) may include a thermally conductive material and may radiate heat generated in the first mirror layer (110) and the second mirror layer (120) to the outside, thereby preventing the DBR structure from being deformed due to heat. The additional pad region (HP) may be arranged in the light emission direction.

[0178] FIGS. 8 to 11 are drawings for explaining a light-emitting device according to a second embodiment of the present invention. FIG. 8 is a plan view of a light-emitting device according to a second embodiment of the present invention. FIG. 9 is a cross-sectional view (A1-A2) of the light-emitting device of FIG. 8. FIG. 10 is another cross-sectional view (A3-A4) of the light-emitting device according to the second embodiment. In addition, FIG. 11 is an enlarged view of an area (R of FIG. 10) of the light-emitting device according to the second embodiment.

[0179] Referring to FIGS. 8 to 10, the light emitting device (1002) of the present embodiment may include a substrate (10), a semiconductor structure (20), an insulating layer (30), and a conductive layer (40).

[0180] The substrate (10) may be a growth substrate for growing a semiconductor structure (20) formed thereon. The type of the substrate (10) may vary depending on the type of the semiconductor structure (20) formed thereon. For example, the substrate (10) may be an n-type GaAs substrate.

[0181] A semiconductor structure (20) may be formed on top of a substrate (10). The semiconductor structure (20) may include a first mirror layer (1210), an active layer (1220), an oxide layer (1230), and a second mirror layer (1240).

[0182] The first mirror layer (1210) may be formed on the upper portion of the substrate (10). According to the present embodiment, the first mirror layer (1210) may include a plurality of n-type semiconductor layers. In addition, the first mirror layer (1210) may be formed by repeatedly stacking a plurality of semiconductor layers having different refractive indices. For example, the first mirror layer (1210) may include a distributed Bragg reflector. For example, the first mirror layer (1210) may be formed by alternately stacking an AlGaAs layer having a relatively low Al content and an AlGaAs layer having a relatively high Al content.

[0183] The active layer (1220) may be formed on the upper portion of the first mirror layer (1210). The lower surface of the active layer (1220) may be in contact with the upper surface of the first mirror layer (1210). The active layer (1220) may generate light through recombination of holes and electrons injected through the second mirror layer (1240) and the first mirror layer (1210). For example, the active layer (1220) may be formed in any one of a single well structure, a multi-well structure, a single quantum well structure, and a multi-quantum well (MQW) structure.

[0184] An oxide layer (1230) may be formed between the active layer (1220) and the second mirror layer (1240). For example, the oxide layer (1230) may be formed as an AlGaAs layer having a higher Al content than the second mirror layer (1240). The oxide layer (1230) may limit a main region that generates light in the active layer (1220).

[0185] Referring to FIG. 9, the oxide layer (1230) may include an oxidation region (1231) and a window region (1232). The oxidation region (1231) may be formed to surround the window region (1232). The oxidation region (1231) may be formed by oxidizing a region of the oxide layer (1230) excluding the window region (1232). In addition, the window region (1232) may be surrounded by the oxidation region (1231) and may serve as a limited current path.

[0186] Since the current flow is limited in the oxidation region (1231), the current from the second mirror layer (1240) to the first mirror layer (1210) can flow intensively through the window region (1232). The current can be injected into the region of the active layer (1220) located below the window region (1232) through the narrow region of the window region (1232). Accordingly, the active layer (1220) can intensively generate light in the narrow region located below the window region (1232). In this way, the oxidation layer (1230) can limit the region of the active layer (1220) that generates and emits light by limiting the path through which the current flows to the window region (1232).

[0187] The second mirror layer (1240) may be formed on top of the oxide layer (1230). According to the present embodiment, the second mirror layer (1240) may include a plurality of p-type semiconductor layers. In addition, the second mirror layer (1240) may be formed by repeatedly stacking a plurality of semiconductor layers having different refractive indices. For example, the second mirror layer (1240) may include a distributed Bragg reflector. For example, the second mirror layer (1240) may be formed by alternately stacking AlGaAs layers having a relatively low Al content and AlGaAs layers having a relatively high Al content.

[0188] In addition, in the present embodiment, the first mirror layer (1210) and the second mirror layer (1240) may each include a plurality of semiconductor layer pairs in which a plurality of semiconductor layers are stacked. In addition, the first mirror layer (1210) and the second mirror layer (1240) may be formed by stacking a plurality of semiconductor layer pairs. For example, the number of semiconductor layer pairs of the second mirror layer (1240) may be less than the number of semiconductor layer pairs of the first mirror layer (1210). In this case, the number of semiconductor layer pairs of the second mirror layer (1240) may be 20 or more, and the number of semiconductor layer pairs of the first mirror layer (1210) may be 30 or more.

[0189] Referring to FIGS. 9 and 10, the semiconductor structure (20) may include a plurality of grooves. The grooves formed in the semiconductor structure (20) may include a first groove (21) and a second groove (22) formed on the inner side of the first groove (21).

[0190] The first groove (21) may be formed so that its bottom surface is made of the second mirror layer (1240), and the second groove (22) may be formed so that its bottom surface is made of the first mirror layer (1210). The first groove (21) may be formed within the second mirror layer (1240) and may be formed to be concave downward from the upper surface of the second mirror layer (1240). Therefore, the bottom surface of the first groove (21) may be formed of the second mirror layer (1240). The upper surface of the semiconductor structure (20), which is the upper surface of the second mirror layer (1240), may include a concave region and a convex region due to the first groove (21) formed in the second mirror layer (1240). That is, the second mirror layer (1240) may include a region having a relatively thick thickness and a region having a relatively thin thickness. According to the present embodiment, the first groove (21) can be formed to surround at least a portion of the light-emitting area from which light of the light-emitting device (1002) is emitted.

[0191] In addition, the second groove (22) may be formed on the inner side of some of the first grooves (21) among the plurality of first grooves (21). At this time, the second groove (22) may be formed to penetrate the second mirror layer (1240), the oxide layer (1230), and the active layer (1220) to expose the first mirror layer (1210). Accordingly, the bottom surface of the second groove (22) may be formed of the first mirror layer (1210).

[0192] According to the present embodiment, since the second groove (22) is formed on the inner side of the first groove (21), the first groove (21) and the second groove (22) are connected to each other. In addition, the diameter of the first groove (21) is larger than the diameter of the second groove (22). In this way, the semiconductor structure (20) can include a groove having an inner wall of a multi-stage structure by the first groove (21) and the second groove (22) being connected to each other. That is, the multi-stage structure groove formed in the semiconductor structure (20) can be formed by two etching processes.

[0193] Briefly describing a part of the manufacturing process of the light-emitting device (1002) according to the present embodiment, a semiconductor structure (20) may be formed on a substrate (10), and a first groove (21) may be formed in a second mirror layer (1240). After the first groove (21) is formed, a portion of an oxide layer (1230) may be oxidized to form an oxide region (1231) surrounding a window region (1232). After the oxidation region (1231) is formed, a second groove (22) may be formed by etching an inner region of the first groove (21) so as to expose the first mirror layer (1210). Through these two etching processes, a groove having a multi-stage inner wall in the semiconductor structure (20) and exposing the first mirror layer (1210) may be formed.

[0194] Typically, in order to form a groove for electrical connection between the first mirror layer (1210) and the conductive layer (40), the semiconductor structure (20) is deeply etched from the second mirror layer (1240) to the first mirror layer (1210) in a single etching process. In this case, since the etching process is performed once, the inner wall of the groove formed in the semiconductor structure (20) becomes a plane, such as a vertical surface or an inclined surface, rather than a multi-stage structure.

[0195] However, since the light-emitting device (1002) of the present embodiment forms a second groove (22) having a smaller diameter than the first groove (21) on the inner side of the first groove (21) that has already been formed, the inner wall of the groove exposing the first mirror layer (1210) formed on the semiconductor structure (20) has a multi-stage structure. Therefore, the inner wall of the multi-stage structure of the groove formed on the semiconductor structure (20) of the present embodiment has a longer length and larger area than the inner wall of the planar structure of the groove. Accordingly, in the case of the present embodiment, the penetration path of foreign substances such as moisture and dust from the outside to the first mirror layer (1210) along the groove formed on the semiconductor structure (20) increases compared to a groove having an inner wall of a planar structure. Therefore, the light-emitting device (1002) according to the present embodiment can prevent performance degradation and reliability degradation due to moisture and dust by increasing the penetration path of foreign substances by the multi-stage structure of the groove.

[0196] In addition, the light emitting device (1002) of the present embodiment forms a second groove (22) in an area where the thickness is reduced by forming the first groove (21) in the semiconductor structure (20). Therefore, the depth of etching to expose the first mirror layer (1210) is reduced compared to when the first groove (21) is not formed. Therefore, the light emitting device (1002) of the present embodiment can reduce the etching thickness of the semiconductor structure (20) to expose the first mirror layer (1210), thereby reducing the time and cost required for the etching process.

[0197] An insulating layer (30) and a conductive layer (40) may be formed on the upper portion of the semiconductor structure (20). The insulating layer (30) may include a first insulating layer (1250) and a second insulating layer (1260). In addition, the conductive layer (40) may include a first conductive layer (1270) and a second conductive layer (1280). The insulating layer (30) may be formed to insulate the first conductive layer (1270) and the second conductive layer (1280) formed on the second mirror layer (1240).

[0198] According to the present embodiment, the first insulating layer (1250) and the second insulating layer (1260) may be formed of an insulating material. In addition, the first insulating layer (1250) and the second insulating layer (1260) may be formed of the same insulating material, but may be formed by including different insulating materials. For example, the first insulating layer (1250) and the second insulating layer (1260) may be formed of silicon oxide (SiO2), silicon nitride (SiN) X ), polyimide or BCB (benzocyclobutene). Furthermore, the first insulating layer (1250) may be formed of at least one of polyimide or BCB. Here, when the first insulating layer (1250) is formed of a material having a low dielectric constant such as BCB, even if it is formed with a thin thickness, the parasitic capacitance can be reduced to prevent the performance of the light-emitting device from being deteriorated. In addition, the second insulating layer (1260) may be formed of at least one of silicon oxide or silicon nitride,

[0199] The first insulating layer (1250) may be formed to cover at least a portion of the upper surface of the second mirror layer (1240). At this time, the first insulating layer (1250) may be formed in an area where the first conductive layer (1270) is formed. That is, the first insulating layer (1250) may be formed under the first conductive layer (1270). In addition, the first insulating layer (1250) may fill the first groove (21) of the semiconductor structure (20). Referring to FIGS. 9 and 10, the upper surface of the first insulating layer (1250) may be positioned higher than the convex region of the second mirror layer (1240).

[0200] The second insulating layer (1260) may be formed on top of the first insulating layer (1250) and may be formed to cover the first insulating layer (1250). In addition, the second insulating layer (1260) may be formed to cover a portion of the semiconductor structure (20). In this case, the second insulating layer (1260) may cover a portion of the second mirror layer (1240) located below the second connection region (1281) of the second conductive layer (1280).

[0201] Additionally, the second insulating layer (1260) may be formed to cover not only the upper surface of the first insulating layer (1250), but also a portion of the first groove (21) and the second groove (22) exposed by the first insulating layer (1250). In more detail, the second insulating layer (1260) may be formed to cover the oxide layer (1230), the active layer (1220), and the first mirror layer (1210) exposed by the second groove (22).

[0202] Referring to FIGS. 9 and 10, the second insulating layer (1260) may include a plurality of openings formed to penetrate from the upper surface to the lower surface of the second insulating layer (1260). The openings of the second insulating layer (1260) may include a first opening (1265) formed between the first connection area (1271) of the first conductive layer (1270) and the first mirror layer (1210) to expose the first mirror layer (1210). In addition, the openings of the second insulating layer (1260) may include a second opening (1266) formed between the second connection area (1281) of the second conductive layer (1280) and the second mirror layer (1240) to expose the second mirror layer (1240). According to this embodiment, the first opening (1265) of the second insulating layer (1260) is located inside the second groove (22), and the light emitting area of ​​the light emitting device (1002) can be located inside the second opening (1266).

[0203] A first conductive layer (1270) and a second conductive layer (1280) may be formed on the upper portion of the insulating layer (30). The first conductive layer (1270) may be electrically connected to the first mirror layer (1210), and the second conductive layer (1280) may be electrically connected to the second mirror layer (1240). The first conductive layer (1270) and the second conductive layer (1280) may be formed of a conductive material. In addition, the first conductive layer (1270) and the second conductive layer (1280) may include at least one of the same conductive material, or may include different conductive materials. In addition, the first conductive layer (1270) and the second conductive layer (1280) may be formed as a single layer, or may be formed as a multilayer. The layer configurations of the first conductive layer (1270) and the second conductive layer (1280) may be the same or different from each other.

[0204] The first conductive layer (1270) and the second conductive layer (1280) may be formed to be spaced apart from each other. At this time, the first conductive layer (1270) may be formed to surround a portion of the second conductive layer (1280).

[0205] Referring to FIG. 9, the second conductive layer (1280) can be formed on top of the first insulating layer (1250) and the second insulating layer (1260).

[0206] Referring to FIG. 8, the second conductive layer (1280) may include a second connection region (1281), a second pad region (1282), and a second connection region (1283). The second pad region (1282) may be electrically connected to an external component such as a circuit board. The second connection region (1281) may be electrically connected to the second mirror layer (1240). In addition, the second connection region (1283) is formed between the second connection region (1281) and the second pad region (1282), such that one end is connected to the second connection region (1281), and the other end is connected to the second pad region (1282). Therefore, the second conductive layer (1280) may apply a voltage received from the external component to the second mirror layer (1240).

[0207] A portion of the second connection region (1283) and the second pad region (1282) may be located on the outer side of the first conductive layer (1270). Here, the outer side of the first conductive layer (1270) may include not only the outer region of the first conductive layer (1270) but also the upper region and the lower region thereof. In addition, another portion of the second connection region (1283) and the second connection region (1281) may be located on the inner side of the first conductive layer (1270).

[0208] The shape of the second connection area (1281) may be a ring shape with some areas open. In addition, the second connection area (1283) may be a long shape to connect the second connection area (1281) and the second pad area (1282). With respect to the plane illustrated in FIG. 8, both sides of the second connection area (1283) connecting the second connection area (1281) and the second pad area (1282) may be straight. According to the present embodiment, the second connection area (1283) may have a constant width (W23) from one end connected to the second connection area (1281) to the other end connected to the second pad area (1282).

[0209] The width (W22) of the second pad area (1282) may be greater than the outer width (W21) of the second connection area (1281) on a parallel line and the width (W23) of the second connection area (1283). In addition, the area of ​​the second pad area (1282) may be greater than the area of ​​the second connection area (1281).

[0210] Additionally, the width (W22) of the second pad area (1282) may be greater than the length (L23) of the second connection area (1283), and the length (L23) of the second connection area (1283) may be greater than the width (W21) of the second connection area (1281). Here, the length (L23) of the second connection area (1283) is the length from one end connected to the second connection area (1281) to the other end connected to the second pad area (1282).

[0211] Accordingly, the second pad area (1282) has a larger area than the second connection area (1283) and the second connection area (1281). The light-emitting device (1002) can have improved heat dissipation performance due to the large area of ​​the second pad area (1282). In addition, the light-emitting device (1002) can be easily electrically connected to an external component due to the large area of ​​the second pad area (1282).

[0212] Referring to FIG. 9, the second connection area (1281) may cover a portion of the second mirror layer (1240) exposed to the outside by the second opening (1266) of the second insulating layer (1260) and may be in contact with the second mirror layer (1240). At this time, the second connection area (1281) may be formed between the inner wall of the second opening (1266) and the light-emitting area of ​​the light-emitting device (1002). That is, the second connection area (1281) may be formed to be in contact with the second mirror layer (1240) outside the light-emitting area. In this way, the second conductive layer (1280) may be electrically connected to the second mirror layer (1240) through the second connection area (1281). Although not shown in this embodiment, an ohmic layer may be further formed between the second connection area (1281) and the second mirror layer (1240) to reduce the contact resistance of the second conductive layer (1280) and the second mirror layer (1240).

[0213] Referring to FIG. 9, the first conductive layer (1270) may be formed on top of the second insulating layer (1260) covering the semiconductor structure (20). In addition, a portion of the first conductive layer (1270) may be formed to fill at least a portion of the first groove (21) and the second groove (22). At this time, the first conductive layer (1270) may be in contact with the first mirror layer (1210) exposed by the first opening (1265) of the second insulating layer (1260) inside the second groove (22). Therefore, the first conductive layer (1270) may be electrically connected to the first mirror layer (1210) inside the second groove (22). Although not shown in this embodiment, an ohmic layer may be further formed between the first connection area (1271) and the first mirror layer (1210) to reduce the contact resistance of the first conductive layer (1270) and the first mirror layer (1210).

[0214] Referring to FIG. 8, the first conductive layer (1270) may include a first connection region (1271), a first pad region (1272), and a first connection region (1273). The first pad region (1272) may be electrically connected to an external component such as a circuit board. The first connection region (1271) may be electrically connected to the first mirror layer (1210) in the second groove (22). In addition, the first connection region (1273) is formed between the first connection region (1271) and the first pad region (1272), such that one end is connected to the first connection region (1271), and the other end is connected to the first pad region (1272). Therefore, the first conductive layer (1270) may apply a voltage received from the external component to the first mirror layer (1210).

[0215] The first connection area (1271) of the first conductive layer (1270) may be formed to surround the second connection area (1281) on the outside of the second connection area (1281) of the second conductive layer (1280). In addition, the first connection area (1273) and the first pad area (1272) may also be located on the outside of the first connection area (1271).

[0216] The shape of the first connection area (1271) may be a ring shape with some areas open. At this time, the second connection area (1283) of the second conductive layer (1280) may pass through the open area between the two ends of the first connection area (1271) to connect the second connection area (1281) and the second pad area (1282). Referring to Fig. 8, the width (W13) of the first connection area (1273) becomes narrower from one end connected to the first connection area (1271) to the other end connected to the first pad area (1272). However, the structure of the first connection area (1273) is not limited thereto. For example, the width of the first connection area (1273) may become wider from one end to the other end, or the width may be constant from one end to the other end.

[0217] In addition, the width (W12) of the first pad area (1272) may be greater than the width (W11) of the first connection area (1271) and the width (W13) of the first connection area (1273) on a parallel line. Here, the width (W11) of the first connection area (1271) is the length from the inner side to the outer side. In addition, the area of ​​the first pad area (1272) may be greater than the area of ​​the first connection area (1271). The light-emitting device (1002) may have improved heat dissipation performance due to the large area of ​​the first pad area (1272). In addition, the light-emitting device (1002) may be easily electrically connected to an external configuration due to the large area of ​​the first pad area (1272).

[0218] The first pad region (1272) of the first conductive layer (1270) and the second pad region (1282) of the second conductive layer (1280) are regions that are electrically connected to an external configuration. Therefore, the first pad region (1272) and the second pad region (1282) can be formed to have a relatively large area compared to other regions of the first conductive layer (1270) and the second conductive layer (1280).

[0219] Referring to FIG. 8, in the present embodiment, the first pad region (1272) of the first conductive layer (1270) and the second pad region (1282) of the second conductive layer (1280) may be disposed adjacent to one side of the light-emitting device (1002). Here, the second pad region (1282) may be disposed adjacent to one corner connected to one side of the light-emitting device (1002). In addition, the first pad region (1272) may be disposed adjacent to another corner connected to one side of the light-emitting device (1002). At this time, the separation distance (L3) between the first pad region (1272) and the second pad region (1282) may be smaller than the width (W12) of the first pad region (1272) and the width (W22) of the second pad region (1282).

[0220] Referring to FIGS. 9 and 10, a second insulating layer (1260) may be positioned in a portion of the area between the conductive layer (40) and the semiconductor structure (20). A portion of the second insulating layer (1260) may be formed to cover a portion of the upper surface of the semiconductor structure (20) below the second connection area (1281) of the second conductive layer (1280). A portion of this second insulating layer (1260) may be a protective area (1264).

[0221] When a conductive layer is formed on a semiconductor layer, cracks may occur in the semiconductor layer due to various stresses, such as excessive force applied to the semiconductor layer or differences in thermal expansion coefficients between the semiconductor layer and the conductive layer. For example, a crack may occur in the area where the lower edge of the conductive layer of the semiconductor layer is located. At this time, if an overcurrent or overvoltage, such as a surge, is applied to the crack through the conductive layer, the crack may grow larger, ultimately causing the semiconductor layer and the light-emitting device to be destroyed.

[0222] To prevent this, the light emitting device of the present embodiment may have a protective region (1264) of a second insulating layer (1260) disposed between the edge of the second connection region (1281) of the second conductive layer (1280) and the semiconductor structure (20).

[0223] Accordingly, the light emitting device (1002) of the present embodiment has a protective region (1264) of the second insulating layer (1260) positioned between the lower edge of the second conductive layer (1280) and the semiconductor structure (20), thereby preventing cracks from occurring in the semiconductor structure (20) due to the second conductive layer (1280), thereby improving reliability.

[0224] In addition, when the semiconductor layer and the conductive layer (40) are in contact, the current applied to the conductive layer (40) can be concentrated at the lower edge of the conductive layer (40) and flow into the semiconductor layer.

[0225] However, according to the present embodiment, the current is not applied to the semiconductor structure (20) through the edge of the second conductive layer (1280) due to the protection region (1264) of the second insulating layer (1260). In addition, the current may flow through the second conductive layer (1280) and be applied to the semiconductor structure (20) at the connection region where the second conductive layer (1280) and the semiconductor structure (20) come into contact. At this time, the connection region is located on the inside of the opening of the second insulating layer (1260).

[0226] Accordingly, the current can flow intensively through the second connection region (1281) by the protection region (1264) of the second insulating layer (1260) between the second conductive layer (1280) and the semiconductor structure (20). That is, the light-emitting device (1002) according to the embodiment of the present invention can allow the current to flow intensively through the connection region adjacent to the light-emitting region, thereby generating and emitting light more intensively within the light-emitting region. In this case, the amount of light generated may decrease in an area other than the light-emitting region due to a decrease in the amount of current. Therefore, the light-emitting device (1002) according to the embodiment of the present invention can reduce the amount of light generated in an area other than the light-emitting region, thereby reducing the light loss, and consequently improving the light-emitting efficiency.

[0227] According to the present embodiment, the inner surface of the second insulating layer (1260) forming the opening located in the first connection area (1271) and the second connection area (1281) may include an inclined surface. Furthermore, the inner surface of the second insulating layer (1260) forming the opening may include a plurality of inclined surfaces. Referring to FIG. 11, the inner surface of the second insulating layer (1260) forming the opening may include a first inclined surface (1267) and a second inclined surface (1268) located below the first inclined surface (1267).

[0228] The first inclined surface (1267) and the second inclined surface (1268) of the second insulating layer (1260) may have different inclinations with respect to the second mirror layer (1240). For example, the inclination angle of the first inclined surface (1267) may be greater than the inclination angle of the second inclined surface (1268). Here, the inclination angle may be an angle formed between the upper surface of the first mirror layer (1210) or the second mirror layer (1240) and the inclined surface of the second insulating layer (1260). Alternatively, the inclination angle is an angle formed between the upper surface of the first mirror layer (1210) or the second mirror layer (1240) and an extension of the inclined surface of the second insulating layer (1260).

[0229] According to the present embodiment, when the first inclined surface (1267) and the second inclined surface (1268) have different inclination angles, the length of the inner surface of the second insulating layer (1260) may increase compared to when the first inclined surface (1267) and the second inclined surface (1268) have the same inclination angle. That is, the inner surface of the second insulating layer (1260) has a greater length when it has a curved structure than when it has a structure made of a single inclination surface. Therefore, the light emitting device (1002) of the present embodiment can increase the length of the inner surface of the second insulating layer (1260) to increase the contact area between the second insulating layer (1260) and the conductive layer (40), thereby improving the adhesive strength between the second insulating layer (1260) and the conductive layer (40).

[0230] In addition, the height of the lower end of the first inclined surface (1267) may be 0.5 times or less than the height of the upper end of the first inclined surface (1267). That is, the height from the upper surface of the second mirror layer (1240) to the point where the first inclined surface (1267) and the second inclined surface (1268) meet may be 0.5 times or less than the height from the upper surface of the second mirror layer (1240) to the upper end of the first inclined surface (1267). Here, the height of the upper end of the first inclined surface (1267) is the height of the second opening (1266).

[0231] According to the present embodiment, the protection region (1264) of the second insulating layer (1260) may include a first region (1261), a second region (1262), and a third region (1263). The first region (1261) is a region among the protection regions (1264) in which the upper surface of the second insulating layer (1260) is flat. The second region (1262) is a region having a first inclined surface (1267) of the second insulating layer (1260). In addition, the third region (1263) is a region having a second inclined surface (1268) of the second insulating layer (1260).

[0232] According to the present embodiment, the width (W41) of the first region (1261) of the protection region (1264) may be greater than the width (W42) of the second region (1262) and the width (W43) of the third region (1263). In addition, the second region (1262) and the third region (1263) of the protection region (1264) may have the same or different widths.

[0233] When depositing a conductive layer (40) on an insulating layer (30), the greater the inclination angle of the insulating layer (30), the more difficult it is to deposit the conductive layer (40). Therefore, in the light-emitting device (1002) according to the present embodiment, the width (W42) of the second region (1262) can be formed to be relatively larger than the width (W43) of the third region (1263), thereby making it easier to form the conductive layer (40).

[0234] That is, the light emitting device (1002) of the present embodiment can increase the width of the region where deposition of the conductive layer (40) is relatively difficult, increase the area of ​​the region in contact with the conductive layer (40), and lower the inclination angle to make it easier to form the conductive layer (40).

[0235] According to the present embodiment, the second conductive layer (1280) may include a hole that opens the light-emitting region. The inner wall forming the hole of the second conductive layer (1280) is the inner surface of the second conductive layer (1280) formed along the edge of the light-emitting region. Therefore, the hole of the second conductive layer (1280) may serve as a passage through which light emitted from the second mirror layer (1240) moves and guides the path of the light.

[0236] Additionally, the second conductive layer (1280) can reflect light. Accordingly, the inner surface of the second conductive layer (1280) can reflect light directed toward the inner surface and direct it toward the upper portion of the light-emitting region.

[0237] In the present embodiment, the light-emitting device (1002) may be formed such that the inner surface of the second conductive layer (1280) surrounding the hole of the second conductive layer (1280) has a multi-stage structure. Accordingly, the second conductive layer (1280) may include a first upper surface (1285), a second upper surface (1287) positioned lower than the first upper surface (1285), a first inner surface (1286), and a second inner surface (1288) positioned lower than the first inner surface (1286).

[0238] The first upper surface (1285) of the second conductive layer (1280) may be positioned between the outer surface and the first inner surface (1286) of the second conductive layer (1280), and the second upper surface (1287) may be positioned between the first inner surface (1286) and the second inner surface (1288). More specifically, one end of the first upper surface (1285) of the second conductive layer (1280) is in contact with the upper end of the outer surface, and the other end is in contact with the upper end of the first inner surface (1286). In addition, one end of the second upper surface (1287) of the second conductive layer (1280) is in contact with the lower end of the first inner surface (1286), and the other end is in contact with the upper end of the second inner surface (1288). Here, the inner surface of the second conductive layer (1280) forming the hole of the second conductive layer (1280) may be a first inner surface (1286), a second inner surface (1288), and a second upper surface (1287) located therebetween. In addition, the width (W52) of the second upper surface (1287) may be greater than the width (W51) of the first upper surface (1285).

[0239] According to the present embodiment, light emitted from the emission surface (25) that does not head toward the upper portion of the light-emitting region may be first reflected by the second inner surface (1288) and head toward the upper portion of the light-emitting region. In addition, light that heads in a direction other than the upper portion of the light-emitting region from the upper portion of the second inner surface (1288) may be reflected by the first inner surface (1286). The light reflected by the first inner surface (1286) may head toward the upper portion of the light-emitting region. In this way, since the light-emitting device (1002) concentrates the light in a certain area by the first inner surface (1286) and the second inner surface (1288) of the second conductive layer (1280), the straightness of the light emitted to the outside may be improved.

[0240] The first inner side surface (1286) and the second inner side surface (1288) of the second conductive layer (1280) may be inclined surfaces having an incline with respect to the second mirror layer (1240). For example, the incline angle of the first inner side surface (1286) and the second inner side surface (1288) of the second conductive layer (1280) may be about 60 degrees or more and about 90 degrees or less.

[0241] Additionally, the first inner side surface (1286) and the second inner side surface (1288) of the second conductive layer (1280) may have different slopes with respect to the upper surface of the second mirror layer (1240). For example, the first inner side surface (1286) of the second conductive layer (1280) may have a greater slope than the second inner side surface (1288). The first inner side surface (1286) having a greater slope can focus light into a narrower area. Therefore, the second conductive layer (1280) having the first inner side surface (1286) having a greater slope than the second inner side surface (1288) can further improve the straightness of light of the light-emitting device (1002).

[0242] FIGS. 12 to 15 are exemplary drawings for explaining light-emitting devices according to the third to sixth embodiments. More specifically, FIGS. 12 to 15 are plan views for explaining the structure of the conductive layer of light-emitting devices according to the third to sixth embodiments.

[0243] Referring to FIGS. 12 to 15, the light emitting devices (1003, 1004, 1005, 1006) according to the third to sixth embodiments may each include a first conductive layer (1270) and a second conductive layer (1380, 1480, 1580, 1680).

[0244] Here, the first conductive layer (1270) of the light-emitting devices (1003, 1004, 1005, 1006) of the third to sixth embodiments has the same structure as the first conductive layer (1270) of the light-emitting device (1002 of FIG. 8) of the second embodiment. Therefore, a detailed description of the first conductive layer (1270) of the light-emitting devices (1003, 1004, 1005, 1006) of the third to sixth embodiments refers to the description of the first conductive layer (1270) of the light-emitting device (1002 of FIG. 8) according to the second embodiment.

[0245] The second conductive layers (1380, 1480, 1580, 1680) of the light-emitting devices (1003, 1004, 1005, 1006) according to the third to sixth embodiments have a different structure from the second conductive layer (1280) of the light-emitting device of the second embodiment (1002 in FIG. 8).

[0246] Referring to FIGS. 12 and 13, the second conductive layers (1380, 1480, 1580, 1680) of the light-emitting devices (1003, 1004) according to the third and fourth embodiments may include a second connection region (1281), a second connection region (1383, 1483), and a second pad region (1282). Here, the second connection regions (1281) and the second pad regions (1282) are the same as the second connection region (1281) and the second pad region (1282) of the light-emitting device of the second embodiment (1002 of FIG. 8).

[0247] Referring to FIGS. 12 and 13, the second connection areas (1383, 1483) of the light-emitting devices (1003, 1004) according to the third and fourth embodiments may have one end connected to the second connection area (1281) and the other end connected to the second pad area (1282). At this time, one end and the other end of the second connection area (1383, 1483) have different widths. For example, one end of the second connection area (1383, 1483) may have a smaller width than the other end of the second connection area (1383, 1483).

[0248] Based on the plane illustrated in Fig. 12, both sides of the second connection area (1383) of the light-emitting device (1003) according to the third embodiment may be in the form of straight lines. In this case, the width of the second connection area (1383) of the light-emitting device (1003) according to the third embodiment may gradually increase from one end to the other.

[0249] Based on the plane illustrated in FIG. 13, the second connection area (1483) of the light-emitting device (1004) according to the fourth embodiment may include a second-first connection area (1483-1) and a second-second connection area (1483-2) that are connected to each other. The second-first connection area (1483-1) may have one end connected to the second connection area (1281), and the other end connected to one end of the second-second connection area (1483-2). In addition, the second-second connection area (1483-2) may have one end connected to the other end of the second-first connection area (1483-1), and the other end connected to the second pad area (1282). Here, the 2-1 connection area (1483-1) of the light-emitting device (1004) according to the 4th embodiment may have the same width from one end to the other end, and the 2-2 connection area (1483-2) may have a width that increases from one end to the other end.

[0250] Referring to FIG. 14, the second conductive layer (1580) of the light-emitting device (1005) according to the fifth embodiment may include a second connection region (1581), a second connection region (1283), and a second pad region (1282). The structure of the second conductive layer (1580) of the light-emitting device (1005) according to the fifth embodiment is identical to that of the second conductive layer (1280) of the light-emitting device (1002 of FIG. 8) according to the second embodiment except for the second connection region (1581).

[0251] According to the fifth embodiment, the second connection area (1581) may be a circular shape without an open area. In addition, a hole is formed on the inner side of the second connection area (1581) that exposes the emission surface (25) corresponding to the light-emitting area. That is, the second connection area (1581) may be a ring shape that exposes the emission surface (25) of the light-emitting device (1005) from the inner side.

[0252] Referring to FIG. 15, the second conductive layer (1680) of the light-emitting device (1006) according to the sixth embodiment may include a second connection region (1581), a second connection region (1683), and a second pad region (1282). The second conductive layer (1680) of the light-emitting device (1006) according to the sixth embodiment has the same structure of other regions except for the second connection region (1683) as the second conductive layer (1680) of the light-emitting device (1005 of FIG. 14) according to the fifth embodiment.

[0253] The second connection area (1683) of the light-emitting device (1006) according to the sixth embodiment may include a second-first connection area (1683-1) and a second-second connection area (1683-2) that are connected to each other. The second-first connection area (1683-1) may have one end connected to the second connection area (1581) and the other end connected to one end of the second-second connection area (1683-2). In addition, the second-second connection area (1683-2) may have one end connected to the other end of the second-first connection area (1683-1) and the other end connected to the second pad area (1282). At this time, the second-second connection area (1683-2) may be formed to have a predetermined angle with the second-first connection area (1683-1). Accordingly, the second connection area (1683) of the light-emitting device (1006) according to the sixth embodiment may have a curved shape.

[0254] The structure of the conductive layer of the light-emitting device of the present invention is not limited to the structure disclosed in the first to sixth embodiments. The conductive layer may have a structure in which the shapes of the connection regions, connection regions, and pad regions disclosed in the first to sixth embodiments are variously combined.

[0255] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art or having ordinary knowledge in the art that the present invention can be variously modified and changed within the scope that does not depart from the spirit and technical scope of the present invention as set forth in the claims to be described below.

[0256] Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the patent claims.

Claims

1. A light emitting device comprising a first mirror layer, a second mirror layer disposed on top of the first mirror layer, a cavity layer disposed between the first mirror layer and the second mirror layer and generating light, and a mesa exposing side surfaces of the second mirror layer and the cavity layer. The second mirror layer includes one or more oxide layers that form an aperture through which light generated in the cavity layer passes, A light emitting device in which the length of the oxide layer from the edge of the oxide layer to the pupil has a value between 0.95 and 1.05 times the diameter of the pupil.

2. In claim 1, A light emitting device wherein the first mirror layer comprises a plurality of first and second refractive index layers sequentially and repeatedly laminated.

3. In claim 1, A light emitting device, wherein the cavity layer comprises a first gap layer on top of the first mirror layer, an active layer on top of the first gap layer, and a second gap layer on top of the active layer.

4. In claim 1, A light emitting device in which the second mirror layer comprises a plurality of first and second refractive index layers sequentially and repeatedly laminated on top of the oxide layer.

5. In claim 4, A light emitting device wherein the second mirror layer further includes a lower spacing layer disposed below the oxide layer.

6. In claim 5, A light emitting device having a plurality of lower spacing layers.

7. In claim 4, A light emitting device comprising a first oxide layer and a second oxide layer on top of the first oxide layer.

8. In claim 7, A light emitting device wherein the length of the first oxide layer is longer than the length of the second oxide layer.

9. In claim 7, A light emitting device wherein the thickness of the first oxide layer is different from the thickness of the second oxide layer.

10. In claim 7, A light emitting device wherein the second mirror layer further comprises an upper spacing layer between the first oxide layer and the second oxide layer.

11. In claim 4, A light emitting device wherein the second mirror layer further comprises a plurality of sub-oxide layers positioned on the outer surface of the second refractive index layer.

12. In claim 11, A light emitting device in which the length of the sub-oxide layer from the edge of the sub-oxide layer to the boundary with the second refractive index layer is shorter than the length of the oxide layer.

13. In claim 11, A light emitting device in which a boundary surface connecting the boundaries between the plurality of sub-oxidation layers and the second refractive index layer forms a curved surface.

14. A light emitting device comprising a first mirror layer, a second mirror layer disposed on top of the first mirror layer, a cavity layer disposed between the first mirror layer and the second mirror layer and generating light, and a mesa exposing side surfaces of the second mirror layer and the cavity layer. It includes a first pad region electrically connected to the first mirror layer, and a second pad region at least partially disposed on the mesa and electrically connected to the second mirror layer, The second mirror layer includes one or more oxide layers that form a pupil through which light generated in the cavity layer passes, The above second pad area has an open portion exposing the upper area of ​​the mesa, A light emitting device in which the open portion overlaps the pupil on a plane, and the diameter of the open portion is larger than the diameter of the pupil.

15. In claim 14, The second pad area includes a connection area forming the open portion and a connection area extending from the connection area, A light emitting device having a concave groove formed on the upper surface of the above connection area.

16. In claim 15, The above grooves are provided in multiple numbers and are a light emitting device concentric with the open portion.

17. In claim 14, It further includes a second electrode disposed on the mesa and electrically connected to the second mirror layer, and an insulating layer disposed on the mesa, exposing at least a portion of the second electrode. A light emitting device wherein the insulating layer comprises a plurality of sub-insulating layers.

18. A light emitting device comprising a first mirror layer, a second mirror layer disposed on top of the first mirror layer, a cavity layer disposed between the first mirror layer and the second mirror layer and generating light, and a mesa exposing side surfaces of the second mirror layer and the cavity layer. The second mirror layer includes one or more oxide layers forming a pupil through which light generated in the cavity layer passes, and a plurality of first and second refractive index layers sequentially and repeatedly laminated on top of the oxide layers. A light emitting device in which the thickness of the oxide layer is thinner than the thickness of the first or second refractive index layer.

19. In claim 1, A light emitting device in which the thickness of the first refractive index layer disposed on the uppermost part of the second mirror layer is at least twice the thickness of the other first refractive index layers.

20. In claim 1, A light emitting device in which the thickness of the oxide layer has a value in the range of 0.3 to 0.4 times the thickness of the first or second refractive index layer.

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