Optoelectronic component with current distribution layer

Abstract

Optoelectronic device (10) comprising an optoelectronic semiconductor chip (11) capable of emitting electromagnetic radiation (15) and comprising a first semiconductor layer (140) of a first conductivity type; a second semiconductor layer (150) of a second conductivity type; a first and a second current distribution layer (180, 160); and a plurality of electrical contact elements (20, 21, 22), wherein the first semiconductor layer (140) is arranged over the second semiconductor layer (150), electromagnetic radiation (15) emitted by the optoelectronic semiconductor chip (11) is emitted via a first main surface (110) of the first semiconductor layer (140), the first current distribution layer (180) is arranged on a side of the second semiconductor layer (150) facing away from the first semiconductor layer (140), and the plurality of electrical contact elements (20, 21, 22) is capable ofto electrically connect the first semiconductor layer (140) to the first current distribution layer (180), the second current distribution layer (160) is electrically connected to the second semiconductor layer (150), and the electrical contact elements (20, 21, 22) comprise a first electrical contact element (20) and a second electrical contact element (21), wherein the first differs from the second electrical contact element, wherein the second current distribution layer (160) is arranged between the first current distribution layer (180) and the second semiconductor layer (150), and the electrical contact elements (20, 21, 22) are insulated from the second current distribution layer (180) by an insulating layer (170), and a laterally measured layer thickness of the insulating layer (170) adjacent to the first contact element (20) differs from the laterally measured layer thickness of the insulating layer (170) adjacent to the second contact element (21).so that the distance between the first contact element (20) and the second current distribution layer (180) is different from the distance between the second contact element (21) and the second current distribution layer (180).

Description

BACKGROUND

[0001] A light-emitting diode (LED) is a light-emitting device based on semiconductor materials. Typically, an LED incorporates a pn junction. When electrons and holes recombine in the pn junction, for example, when a suitable voltage is applied, electromagnetic radiation is produced. LEDs have been developed for a wide variety of applications, including displays, lighting devices, automotive lighting, projectors, and more. For example, arrays of LEDs or light-emitting diodes, each containing multiple LEDs or light-emitting diodes, are widely used for these purposes.

[0002] The present invention is based on the objective of providing an improved optoelectronic component and an improved method for manufacturing an optoelectronic component.

[0003] According to the present invention, the problem is solved by the subject matter of the independent claims. Advantageous further developments are defined in the dependent claims. SUMMARY

[0004] According to embodiments, an optoelectronic device comprises an optoelectronic semiconductor chip capable of emitting electromagnetic radiation and includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a first and a second current distribution layer, and a plurality of electrical contact elements. The first semiconductor layer is arranged above the second semiconductor layer. Electromagnetic radiation emitted by the optoelectronic semiconductor chip is emitted via a first primary surface of the first semiconductor layer. The first current distribution layer is arranged on a side of the second semiconductor layer facing away from the first semiconductor layer. The plurality of electrical contact elements is capable of electrically connecting the first semiconductor layer to the first current distribution layer.The second current distribution layer is electrically connected to the second semiconductor layer. The electrical contact elements comprise a first electrical contact element and a second electrical contact element, the first being different from the second.

[0005] According to embodiments, the semiconductor chip comprises a plurality of active regions, each located in a region between the first and second semiconductor layers and between the electrical contact elements. The first electrical contact element is connected to a corresponding active region via a first resistance value, and the second electrical contact element is connected to a corresponding active region via a second resistance value. The first resistance value differs from the second resistance value. According to an alternative interpretation, an active region can be located between the first and second semiconductor layers and be interrupted by the electrical contact elements. In this case, the term "resistance value" refers to the resistance between the electrical contact and the corresponding section of the active region.The active region can, for example, be a pn junction between the first and second semiconductor layers.

[0006] According to further embodiments, the active region can also comprise a heterostructure or one or more quantum wells.

[0007] For example, the electrical contact elements can extend through the second semiconductor layer and be insulated from the material of the second semiconductor layer by an insulating layer. According to embodiments, the diameter of the first contact element can differ from the diameter of the second contact element.

[0008] According to embodiments, the second current distribution layer can be arranged between the first current distribution layer and the second semiconductor layer. The electrical contact elements can be isolated from the second current distribution layer by an insulating layer.

[0009] The optoelectronic component can further comprise a contact layer suitable for electrically connecting the second current distribution layer to the second semiconductor layer. The lateral distance from the contact layer to the first contact element can differ from the lateral distance from the contact layer to the second contact element.

[0010] According to further embodiments, a laterally measured layer thickness of the insulating layer adjacent to the first contact element can differ from the laterally measured layer thickness of the insulating layer adjacent to the second contact element.

[0011] For example, the first current distribution layer can be connected to a first terminal area located on a first main surface of the semiconductor chip. In this case, the first contact element is located closer to the first terminal area than the second contact element, and the first has a higher resistance than the second.

[0012] According to the embodiments, the sum can S1 from supply resistances through the first and second current distribution layers and series resistances through the first and second semiconductor layers for the first electrical contact element and the sum S2 The following relationship must be satisfied for the second electrical contact element from the supply resistances through the first and second current distribution layers and the series resistances through the first and second semiconductor layers: |S1-S2| / S1 < 0.1.

[0013] For example, the first current distribution layer can be connected to a first terminal area, and the second current distribution layer can be connected to a second terminal area. The first and second terminal areas are each located on a first main surface of the optoelectronic device.

[0014] According to further embodiments, the optoelectronic semiconductor chip can be mounted on a heat-dissipating substrate with areas of differing thermal conductivity. For example, the second contact element is located in an area with better thermal conductivity than the area in which the first contact element is located.

[0015] For example, the heat-dissipating carrier can connect the first power distribution layer to a first connection area and connect the second power distribution layer to a second connection area.

[0016] A method for fabricating an optoelectronic device comprises forming an optoelectronic semiconductor chip capable of emitting electromagnetic radiation. The optoelectronic semiconductor chip includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a first and a second current distribution layer, and a plurality of electrical contact elements. The first semiconductor layer is arranged above the second semiconductor layer. Electromagnetic radiation emitted by the optoelectronic semiconductor chip is emitted via a first primary surface of the first semiconductor layer. The first current distribution layer is arranged on a side of the second semiconductor layer facing away from the first semiconductor layer. The plurality of electrical contact elements is suitable for electrically connecting the first semiconductor layer to the current distribution layer.The array of electrical contact elements comprises a first electrical contact element and a second electrical contact element. The second current distribution layer is electrically connected to the second semiconductor layer. The method further includes setting a resistance value of a first electrical contact element and a second electrical contact element such that the sum... S1 from lead resistances through the first and second contact layers and series resistances through the first and second semiconductor layers for the first electrical contact element and the sum S2 The following relationship must be satisfied for the second electrical contact element from the lead resistances through the first and second contact layers and the series resistances through the first and second semiconductor layers: |S1-S2| / S1 < 0.1.

[0017] For example, the formation of an optoelectronic semiconductor chip can include forming the first semiconductor layer of the first conductivity type on a growth substrate, forming the second semiconductor layer of the second conductivity type over the first semiconductor layer, forming the second current distribution layer over the second semiconductor layer, forming a plurality of electrical contact elements, and forming the first current distribution layer over the second current distribution layer, resulting in a layer stack. The process for fabricating the optoelectronic device can further include the subsequent deposition of the layer stack onto a support and the subsequent removal of the growth substrate.

[0018] According to embodiments, an electrical device comprises the described optoelectronic component. The electrical device can be selected from the group consisting of vehicle headlights, projectors, and lighting devices. List of characters

[0019] The accompanying drawings serve to illustrate exemplary embodiments of the invention. The drawings depict these embodiments and, together with the description, explain them. Further exemplary embodiments and many of the intended advantages will become apparent from the detailed description below. The elements and structures shown in the drawings are not necessarily drawn to scale. Identical reference numerals refer to identical or corresponding elements and structures. Fig. Figure 1A shows a schematic cross-sectional view of a part of an optoelectronic component according to embodiments. Fig. Figure 1B shows a schematic horizontal cross-sectional view of an optoelectronic component according to embodiments. Fig. 2A and Fig. Figure 2B shows schematic cross-sectional views through parts of an optoelectronic component. Fig. Figure 3A shows a schematic cross-sectional view through parts of an optoelectronic component according to further embodiments. Fig. Figure 3B shows a schematic horizontal cross-sectional view through part of an optoelectronic component. Fig. Section 4 summarizes a method according to embodiments. Fig. Figure 5 shows an electrical device according to embodiments. DETAILED DESCRIPTION

[0020] The following detailed description refers to the accompanying drawings, which form part of the disclosure and show specific embodiments for illustrative purposes. In this context, directional terminology such as "top," "bottom," "front," "back," "over," "on," "in front," "behind," "front," "back," etc., refers to the orientation of the figures just described. Since the components of the embodiments can be positioned in different orientations, the directional terminology serves only for explanation and is in no way restrictive.

[0021] The description of the embodiments is not limiting, as other embodiments exist and structural or logical modifications can be made without deviating from the scope defined by the claims. In particular, elements of the embodiments described below can be combined with elements of other described embodiments, unless the context indicates otherwise.

[0022] The terms "wafer" or "semiconductor substrate" used in the following description can encompass any semiconductor-based structure that has a semiconductor surface. Wafer and structure are to be understood as including doped and undoped semiconductors, epitaxial semiconductor layers, optionally supported by a substrate, and other semiconductor structures. For example, a layer of a first semiconductor material may be grown on a growth substrate of a second semiconductor material or of an insulating material, such as a sapphire substrate. Depending on the intended use, the semiconductor may be based on a direct or an indirect semiconductor material.Examples of semiconductor materials particularly suitable for generating electromagnetic radiation include, in particular, nitride semiconductor compounds, which can generate, for example, ultraviolet, blue, or longer-wavelength light, such as GaN, InGaN, AlN, AlGaN, AlGaInN; phosphide semiconductor compounds, which can generate, for example, green or longer-wavelength light, such as GaAsP, AlGaInP, GaP, AlGaP; and other semiconductor materials such as AlGaAs, SiC, ZnSe, GaAs, ZnO, Ga₂O₃, diamond, hexagonal BN, and combinations of these materials. The stoichiometric ratio of the ternary compounds can vary. Further examples of semiconductor materials include silicon, silicon-germanium, and germanium. In the context of this description, the term "semiconductor" also includes organic semiconductor materials.

[0023] The terms "lateral" and "horizontal," as used in this description, are intended to describe an orientation or alignment that is essentially parallel to a first surface of a substrate or semiconductor body. This could be, for example, the surface of a wafer, a die, or a chip.

[0024] The term “vertical”, as used in this description, is intended to describe an orientation that is essentially perpendicular to the first surface of the substrate or semiconductor body.

[0025] Where terms such as "have," "contain," "comprise," "exhibit," and the like are used here, they are open terms that indicate the presence of the elements or characteristics mentioned, but do not exclude the presence of further elements or characteristics. The indefinite and definite articles include both the plural and the singular, unless the context clearly indicates otherwise.

[0026] In the context of this description, the term "electrically connected" means a low-resistance electrical connection between the connected elements. The electrically connected elements do not necessarily have to be directly connected to each other. Other elements can be positioned between electrically connected elements.

[0027] The term "electrically connected" also includes tunnel contacts between the connected elements.

[0028] Fig. Figure 1A shows a schematic cross-sectional view through a portion of an optoelectronic component according to embodiments. The optoelectronic component 10 includes an optoelectronic semiconductor chip 11 , which is suitable for electromagnetic radiation 15 to emit. The optoelectronic semiconductor chip comprises a first semiconductor layer. 140 of a first conductivity type, for example n-type, and a second semiconductor layer 150 of a second conductivity type, for example p-type. The optoelectronic semiconductor chip also contains a first current distribution layer. 180 as well as a large number of electrical contact elements 20 , 21 , 22 The first semiconductor layer 140 is above the second semiconductor layer 150 arranged. That is, the second semiconductor layer 150 is between the first semiconductor layer 140and the first power distribution layer 180 arranged. Electromagnetic radiation emitted by the optoelectronic semiconductor chip 15 is accessed via a first main surface 110 the first semiconductor layer 140 issued. The first power distribution layer 180 is on one of the first semiconductor layers 140 far side of the second semiconductor layer 150 arranged.

[0029] The multitude of electrical contact elements or plugs 20 , 21 , 22 is suitable for the first semiconductor layer 140 with the first power distribution layer 180 to connect electrically. The electrical contact elements 22 include a first electrical contact element 21 and a second electrical contact element 21 , where the first electrical contact element differs from the second.

[0030] The optoelectronic semiconductor chip 11 It can contain additional layers. For example, the optoelectronic semiconductor chip can 11 furthermore, a second power distribution layer 160 include the second power distribution layer. 160 can be between the first current distribution layer and the second semiconductor layer 150 be arranged. The electrical contact elements 20 , 21 , 22 extend, for example, through the second semiconductor layer 150 and through the second current distribution layer and can pass over an insulating layer 202 from the second semiconductor layer 150 and from the second power distribution layer 160 be electrically insulated. The interior of the electrical contact elements 20 , 21 , 22 is made with a conductive material 200 , 201filled. For example, the conductive material can form part of the first current distribution layer. 180 include.

[0031] According to specific embodiments, the semiconductor chip can have a variety of active areas. 142 encompassing each located in an area between the first and second semiconductor layers 140 , 150 are arranged. For example, the active region features a pn junction, a double heterostructure, a single quantum well (SQW), or a multi quantum well (MQW) for radiation generation. The term "quantum well structure" here has no bearing on the dimensionality of the quantization. It thus includes, among other things, quantum wells, quantum wires, and quantum dots, as well as any combination of these structures. The described semiconductor chip is connected via an adhesive layer or interconnect layer. 190 on a carrier substrate 100attached. For example, the carrier substrate 100 Contains aluminum nitride. The carrier substrate 100 It can be insulating and, for example, a glass substrate. A backside metallization 130 is on the second main surface or back 120 of the carrier substrate 100 upset.

[0032] The electrical contact elements 20 , 21 , 22 They can, for example, be designed in the form of a circular cylinder, an elliptical cylinder, a cuboid, a cone or truncated cone, a pyramid, or a truncated pyramid. According to further embodiments, the contact element can 20 , 21 , 22 It may also be in the form of a trench whose longitudinal axis extends in a y-direction. The first electrical contact element 20 is in a first contact opening 207 formed. The second electrical contact element 21is in a second contact opening 208 trained.

[0033] According to embodiments, the first current distribution layer can 180 as well as the second power distribution layer 160 via connection areas (not shown in Fig. 1A), which are located, for example, in the area of ​​the first main surface of the optoelectronic component 10 The connection areas can be located at the edge of the optoelectronic component. However, according to other embodiments, the connection areas can also be located on the back side. 120 of the carrier substrate 100 be arranged. For example, the light-emitting front of the semiconductor chip is free of electrical contact points such as bond pads. Only the contact elements 20 , 21 , 22are located in the area of ​​the first surface. In this way, the risk of shadowing and / or absorption of a portion of the electromagnetic radiation emitted by the active areas during operation is reduced. 15 reduced by such connection surfaces.

[0034] For example, the semiconductor chip 11 A thin-film LED chip. A substrate. 100 is at the first semiconductor layer 140 far side of the second semiconductor layer 150 arranged. For example, the carrier substrate 100 from the growth substrate on which the semiconductor layer sequence has grown, which, for example, forms the first semiconductor layer 140 , the active area 142 as well as the second semiconductor layer 150 encompasses various materials. In particular, a material of the first and second semiconductor layers can be 140 , 150, be GaN-based, i.e., consist of or contain GaN. Specific examples include InGaN, AlGaN, or InAlGaN. A layer thickness of the first semiconductor layer 140 is larger than 100 nm, for example, more than 500 nm, for example, about 1 µm. The second semiconductor layer 150 has a layer thickness of less than 500 nm, for example less than 200 nm, for example more than 50 nm. The second semiconductor layer 150 For example, it has a lower electrical conductivity than the first semiconductor layer 140 The second semiconductor layer 150 can, for example, be applied over a wide area with the second power distribution layer 160 be connected. According to further embodiments, the second semiconductor layer 150 via an additional contact layer (not shown in Fig. 1A) with the second power distribution layer 160 connected. In contrast, the first semiconductor layer is 140via a multitude of electrical contact elements 20 , 21 , 22 with the first power distribution layer 180 tied together.

[0035] A passivation layer 195 , for example, silicon oxide, silicon nitride or a combination of these materials is above the first main surface 110 the first semiconductor layer 140 arranged.

[0036] As in Fig. As indicated by 1A, the first electrical contact element differs. 20 from the second electrical contact element 21 .

[0037] Fig. Figure 1B shows a top view of part of an optoelectronic component. 10 according to embodiments. As can be seen, the optoelectronic component comprises 10 a large number of electrical contact elements 20 The electrical contact elements include first electrical contact elements 20as well as second electrical contact elements 21 The first electrical contact element 20 differs from the second electrical contact element 21 The optoelectronic component 10 can, for example, create a first connection area 210 as well as a second connection area 211 include, for example, the first connection area. 210 as well as the second connection area 211 in the area of ​​a first main surface 115 of the optoelectronic component 10 be arranged. The first connection area 210 for example, via the first power distribution layer 180 as well as the electrical contact elements 20 , 21 , 22 with the first semiconductor layer 140 electrically conductive connection. The second connection area 211 is via the second power distribution layer 160with the second semiconductor layer 150 Electrically conductive connection. The described optoelectronic component is typically used at currents greater than 1 A / mm². 2 operated. For example, current densities can be approximately 5 A / mm². 2 For example, the diameter of the first or second contact element can be... 20 , 21 Each must be greater than 0.5 µm. For example, the diameter of the first or second contact element may be greater. 20 , 21 The distance between each contact element can be less than 100 µm. The distance between each contact element can be greater than 1 µm. The distance between each contact element can be less than 300 µm.

[0038] The feature “the first contact element differs from the second electrical contact element” means, for example, within the scope of the present disclosure, that the connection resistance of the first electrical contact element 20the electrical contact resistance of the second electrical contact element may differ from that of an associated active area. 21 to a corresponding active area. This can be achieved, for example, by using an electrically conductive material. 200 of the first contact element 20 has a different conductivity than the electrically conductive material 201 (shown in Fig. 1A) of the second electrical contact element. According to further embodiments, the shape or dimensions of the electrical contact elements can be different. For example, the first electrical contact element 20 have a larger cross-sectional area than the second electrical contact element 21 As a consequence of the larger cross-sectional area, the electrical resistance of the first electrical contact element can, for example, be lower than the electrical resistance of the second electrical contact element.21 .

[0039] According to further embodiments, the length of the electrical path between the electrical contact element and the active area connected to the electrical contact element can vary. This can be, as in Fig. 1A indicated, for example, by measuring the laterally measured thickness of the insulating layer. 202 , which form the conductive filling of the electrical contact element relative to the adjacent second semiconductor layer 150 It is isolated and adjusted accordingly. For example, this allows the distance of the active area to be adjusted. 142 to the associated electrical contact element or electrically conductive filling 201 of the second electrical contact element 21 are increased, thereby increasing the resistance to the first electrical contact element. 20 is enlarged. This list is not exhaustive; further possibilities will be discussed below.

[0040] Because the first electrical contact element differs from the second electrical contact element, different areas of the optoelectronic semiconductor chip can be energized. 11 can be achieved as needed. For example, the respective contact elements can be 20 , 21 , 22 It should be designed such that those contact elements located closer to the associated connection area, which are typically exposed to excessively high current density at the intended operating currents, have a higher connection resistance than other contact elements located further away from the associated connection area.

[0041] This prevents inhomogeneous current densities and indentations. As a result, the temperature gradient across the chip can be reduced. Furthermore, inhomogeneous luminance, which could result from inhomogeneous current density, can be avoided. Consequently, more homogeneous light can be generated. Additionally, degradation of the contact elements, especially those located near the first contact area, can be prevented. 210 This prevents the formation of faulty components. Consequently, the aging of the optoelectronic component can be reduced. Due to the increased homogeneity of the current application, overall greater efficiency is achieved.

[0042] Typically, the contact elements located near the first connection area are 210The contact elements are arranged in such a way that very high current densities are achieved locally. According to embodiments, the contact elements can be designed such that the series resistance of those electrical contact elements is low. 22 , which are located near the first connection area 210 are arranged, is increased, while the series resistance of those electrical contact elements 22 , which are located at a certain distance from the first connection area 210 are arranged depending on the distance to the first connection area 210is reduced. For example, the calculation can be performed in such a way that the sum of the lead resistances (each through the first current distribution layer and the second current distribution layer) and the series resistances, which are defined by the connection resistance between the electrical contact element and the associated active area, are each equal. For example, this connection resistance can be determined in particular by the distance to be overcome in the first semiconductor layer. 140 This must be determined. This ensures a uniform current flow to all electrical contact elements.

[0043] In general terms, the sum S1 from lead resistances through the first and second contact layers and series resistances through the first and second semiconductor layers for the first electrical contact element and the sum S2The following relationship must be satisfied for the second electrical contact element based on the lead resistances through the first and second contact layers and the series resistances through the first and second semiconductor layers: |S1-S2| / S1<0.3. According to further embodiments, the following relationship may apply: |S1-S2| / S1<0.1 or |S1-S2| / S1<0.05.

[0044] The Fig. 2A and Fig. Figure 2B shows cross-sectional views through a first and a second electrical contact element. 20 , 21 The cross-sections each run along the directions shown in Fig. 1B is indicated. More precisely, the representation in Fig. 2A a cross-sectional view showing a cross-section through a first contact element (knob) between II and III 20 The area between I and II shows part of the second connection area. 211 to the edge of the contact element 20The cross-sectional view between III and IV shows the area between the first contact element. 20 and edge of the arrangement of contact elements. The cross-sectional view between IV and V shows a cross-section through a first connection area. 210 . Fig. 2B is recorded in a similar manner. The cross-sectional view between II' and III' shows the cross-section through a second electrical contact element (knob). 21 .

[0045] The in Fig. 2A Semiconductor component shown 10 includes a first semiconductor layer 140 of a first conductivity type and a second semiconductor layer 150 of a second conductivity type. A first current distribution layer 180 is on one of the first semiconductor layers 140 far side of the second semiconductor layer 150 arranged. Furthermore, a second power distribution layer is 160between the second semiconductor layer 150 and first power distribution layer 180 arranged. The first and second power distribution layers 180 , 160 They can be metallic, for example, an alloy of Ti / Pt, Au, or any of these metals. Furthermore, the current distribution layer can be... 160 , 180 They also contain nickel. The composition of the current distribution layers can vary.

[0046] For example, the second power distribution layer 160 via a contact layer 165 , which is reflective, for example, with the second semiconductor layer 150 be connected. For example, the contact layer can 165 It should be designed as a silver mirror. This contact layer 165 Firstly, it ensures good electrical contact with the second current distribution layer. 160 and the second semiconductor layer 150Certainly. Furthermore, the contact layer reflects. 165 electromagnetic radiation emanating from the active area 142 in the direction of the carrier substrate 100 was radiated back towards the first main surface 110 back to the first semiconductor layer.

[0047] The first power distribution layer 180 is through an insulating layer 170 from the second power distribution layer 160 insulated. For example, the insulating layer can contain silicon oxide, silicon nitride, or a combination of these materials. The electrical contact element 20 , which is the first power distribution layer 180 with the first semiconductor layer 140 connects, is in initial contact opening 207 arranged, forming the second semiconductor layer 150 and the second power distribution layer 160 penetrates. Part of the insulation layer 170is between the side wall of the first contact opening 207 and the second power distribution layer 160 arranged to provide electrically conductive filling for the contact element 20 from the second power distribution layer 160 to insulate. An insulating layer. 202 It is applied to a side wall of the first contact opening. For example, the insulating layer can 202 The insulating layer contains or consists of SiOx, SiN, or other dielectric layers. 202 For example, the electrically conductive material 200 from the second semiconductor layer 150 Electrically insulate or protect the active area. For example, the side walls of the first contact opening 207 with a reflective conductive layer 205 , for example, lined with a silver mirror. More precisely, the side walls and horizontal areas of the contact opening can be lined with silver mirror.207 with the reflective conductive layer 205 It must be covered. Furthermore, a horizontal area of ​​the reflective conductive layer must be present. 205 at the interface to the first semiconductor layer 140 trained. The reflective conductive layer 205 is, for example, dimensioned in such a way that it is approximately or partially aligned with the contact layer in the horizontal direction. 165 overlap. This also reduces electromagnetic radiation directed towards the substrate. 100 is broadcast by the shift 205 and the contact layer combined with it 165 reflected.

[0048] For example, in such an implementation, the first contact element can be designed differently from the second contact element, such that the horizontal distance between the contact layers 165 and contact element 20 , 21 , 22 is varied.

[0049] A protective layer 196 , which for example contains or consists of Al2O3, can be applied above the first semiconductor layer 140 be arranged. This protective layer 196 For example, it can protect the semiconductor layers from moisture.

[0050] A part 145 the first main surface 110 the first semiconductor layer 140 It may be roughened to improve the coupling efficiency of generated electromagnetic radiation into the adjacent passivation layer. 195 to improve.

[0051] Fig. Figure 2B shows a cross-sectional view through a corresponding second contact element. For example, the second electrical contact elements have 21 , which are located near the first connection area 210 are arranged with a distance between the contact opening that is a few µm larger 208 and contact layer 165 as the first electrical contact elements 20, which are further from the first connection area 210 are removed. As a result, in the vicinity of the connection area... 210 a path of the current from the second electrical contact elements 21 through the first semiconductor layer 140 longer, which increases the series resistance. Conversely, the series resistance of the first electrical contact elements decreases. 20 , which are further from the first connection area 210 removed, reduced.

[0052] As can be seen, the insulation layer still has a horizontal width d1. 170 The second contact element is significantly larger than a horizontal width d0 of the insulating layer. 170 at a first contact element. Furthermore, a lateral dimension of the contact layer is required. 165Near the second contact element, the lateral dimension of the contact layer is smaller than near the first contact element. As a result, the series resistance is lower. R1 between the conductive filling 200 of the second contact element 21 and an associated active region between the first semiconductor layer 140 and second semiconductor layer 150 exhibit a higher resistance value than the resistance value R0 between the conductive filling 200 of the first contact element 20 and the associated active region between the first semiconductor layer 140 and second semiconductor layer 150 . Due to the horizontal expansion of the contact layer 165 The position of the electrical contact between the first semiconductor layer is determined. 140 and second semiconductor layer 150 determined by the fact that, as in Fig. 2B illustrates the position of the contact layer 165When the second electrical contact element is shifted horizontally, its resistance increases. Accordingly, a resistance value can be adjusted by appropriately structuring the contact layer. 165 be determined.

[0053] According to embodiments of the Fig. 2A and Fig. 2B is the first connection area 210 , which is connected to the first power distribution layer 180 is connected to a first main surface 115 of the optoelectronic component 10 arranged. Furthermore, the second connection area 211 in the area of ​​the first main surface 115 of the optoelectronic component. According to further embodiments, the first connection area can be 210 and / or the second connection area 211 It can also be arranged in other positions. A passivation layer 195 is positioned above the optoelectronic component.

[0054] According to further embodiments, the optoelectronic semiconductor chip can have a conductive substrate instead of an insulating substrate. For example, as in Fig. Figure 3A illustrates the arrangement of the first, second semiconductor layer and second current distribution layer. 160 over an electrically conductive support 225 be arranged. For example, the support serves 225 as a heat-dissipating element.

[0055] The electrically conductive support 225 includes a first electrically conductive support element 220 and a second electrically conductive support element 222 For example, the electrically conductive support element is connected to the semiconductor layer sequence in such a way that it acts as the first current distribution layer and is connected via electrical contact elements. 21 , 20 with the first semiconductor layer 140is connected. The second electrically conductive support element 222 is in relation to the first electrically conductive support element 220 isolated and with the second power distribution layer 160 connected. In this way, the first connection area can be 210 as well as the second connection area 211 on the back side of the optoelectronic device, i.e., on a side facing away from the semiconductor layer sequence.

[0056] As in Fig. 3A is the electrically conductive carrier 225 structured, i.e., in a peripheral area, the carrier 225 a greater thickness than in a central region of the optoelectronic component. Accordingly, heat dissipation in the central region with layer thickness s1 is significantly lower than in a peripheral region with layer thickness s2. As in Fig. As illustrated in 3A, it is now planned that the second contact elements21 They are each arranged adjacent to the area with reduced heat dissipation or thickness s2 of the carrier. The first contact elements 20 are arranged in an area with greater heat dissipation or thickness s1 of the carrier. This is because the second contact elements are arranged in a similar manner to those in Fig. As shown in 2B, due to the increased resistance in the area of ​​the second contact elements, a reduced current flows, resulting in lower heat generation.

[0057] The first and second electrical contact elements 20 , 21 are, for example, each as in Fig. 2B shows the lateral width of the insulation layer. 170 between the side wall of the contact opening and the contact layer 165The resistance at the first contact elements differs from that at the second contact elements. This is because the resistance in the area of ​​the second contact elements is higher. 21 By increasing the thermal conductivity, the problem of inhomogeneous heat dissipation can be effectively compensated for. More precisely, less heat is generated in the central area of ​​the optoelectronic component, resulting in a more homogeneous heat distribution within the semiconductor chip. In areas with good thermal conductivity, more current is conducted through the electrical contact elements than in areas with poor thermal connectivity. The series resistance is increased in the area with poor thermal connectivity, thus reducing the current and consequently the heat generation in this area. For example, in the area of ​​the second contact element... 21 the distance between contact layer 165and contact element typically increased by 10 µm compared to a first contact element. Again, a protective layer can be applied. 196 as described above above the first semiconductor layer 140 be arranged.

[0058] Fig. 3B shows a schematic horizontal cross-sectional view through parts of the in Fig. Figure 3A shows the optoelectronic component. The optoelectronic component has a multitude of electrical contact elements. 22 on. The electrical contact elements include first electrical contact elements 20 and second electrical contact elements 21 As in Fig. 3B shows the first electrical contact elements. 20 in a peripheral area of ​​the carrier 225 arranged with improved thermal bonding, while the second electrical contact elements 21 in a central area of ​​the carrier 225are arranged with reduced thermal contact. As with reference to Fig. 3A explains how the second electrical contact elements differ from the first electrical contact elements. Fig. 3B also illustrates positions of the in Fig. Cross-sectional view shown in 3A.

[0059] According to embodiments, a method for manufacturing an optoelectronic device comprises forming an optoelectronic semiconductor chip capable of emitting electromagnetic radiation and comprising a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a first and a second current distribution layer, and a plurality of electrical contact elements. The first semiconductor layer is arranged above the second semiconductor layer. Electromagnetic radiation emitted by the optoelectronic semiconductor chip is emitted via a first primary surface of the first semiconductor layer. The first current distribution layer is arranged on a side of the second semiconductor layer facing away from the first semiconductor layer. The plurality of electrical contact elements is capable of electrically connecting the first semiconductor layer to the current distribution layer.The array of electrical contact elements comprises a first electrical contact element and a second electrical contact element. The second current distribution layer is electrically connected to the second semiconductor layer. The method further includes setting a resistance value of a first electrical contact element and a second electrical contact element such that the sum... S1 from lead resistances through the first and second contact layers and series resistances through the first and second semiconductor layers for the first electrical contact element and the sum S2 The following relationship must be satisfied for the second electrical contact element from the lead resistances through the first and second contact layers and the series resistances through the first and second semiconductor layers: |S1-S2| / S1 < 0.3 or |S1-S2| / S1 < 0.1.

[0060] For example, as in Fig. Figure 4 shows the formation of an optoelectronic semiconductor chip ( S100 ) the first semiconductor layer of the first conductivity type on a growth substrate, the formation ( S200 ) the second semiconductor layer of the second conductivity type above the first semiconductor layer, the formation ( S300 ) the second current distribution layer above the second semiconductor layer, the formation ( S400 ) a large number of electrical contact elements, and the formation ( S500 ) the first current distribution layer over the second current distribution layer, resulting in a layer stack. The process for manufacturing the optoelectronic device includes the subsequent deposition ( S600 ) of the layer stack on a carrier and the subsequent detachment ( S700 ) of the growth substrate.

[0061] Setting a resistance value ( S450) of a first electrical contact element and a second electrical contact element such that the sum S1 from lead resistances through the first and second contact layers and series resistances through the first and second semiconductor layers for the first electrical contact element and the sum S2 The described relationship between the supply resistances through the first and second contact layers and the series resistances through the first and second semiconductor layers for the second electrical contact element can be part of the method for forming a large number of electrical contact elements.

[0062] As described, the resistance of individual contact elements can be adjusted by modifying their properties. Accordingly, the current flowing through each contact element can be adjusted to meet the requirements of the optoelectronic component. For example, this can result in a more uniform or homogeneous current distribution across the contact elements of the optoelectronic component. In further embodiments, the current can be adjusted to the heat dissipation of the optoelectronic component. For instance, a higher current can be applied to areas with better heat dissipation than to areas with poorer heat dissipation. As a result, the efficiency and lifetime of the optoelectronic semiconductor component can be increased. Furthermore, a more homogeneous luminance can be achieved.For example, even at high current densities, the emission pattern of the optoelectronic component cannot change with the operating current.

[0063] Because of these effects, the optoelectronic component can be combined with optical elements, for example. Application areas include, for example, car headlights, but also projection and lighting applications. Fig. 5 shows an electrical device 30 according to embodiments. The electrical device 30 The described optoelectronic component includes 10 For example, the electrical device can also include an optical element. 31 This includes electrical devices. Examples of electrical devices are vehicle headlights, projectors, and lighting devices.

[0064] Although specific embodiments have been illustrated and described herein, those skilled in the art will recognize that the specific embodiments shown and described can be replaced by a multitude of alternative and / or equivalent embodiments without departing from the scope of protection of the invention. The application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, the invention is limited only by the claims and their equivalents. Reference symbol list 10 Optoelectronic component 11 Optoelectronic semiconductor chip 15 emitted electromagnetic radiation 20 first electrical contact element 21 second electrical contact element 22 electrical contact element 30 electrical devices 31 optical element 100 carrier substrate 110 first main surface 115 first main surface of the component 120 second main surface 130 Backside metallization 140 first semiconductor layer 142 active area 145 roughened surface of the first semiconductor layer 150 second semiconductor layer 160 second power distribution layer 165 Contact layer 170 Insulation layer 180 first power distribution layer 190 Compound layer 195 Passivation layer 196 Protective layer 200 electrically conductive material 201 Electrically conductive material of the first contact 202 insulating layer 205 reflective conductive layer 207 first contact opening 208 second contact opening 210 first connection area 211 second connection area 220 first electrically conductive support element 222 second electrically conductive support element 225 carriers

Claims

[1] Optoelectronic component (10) comprising an optoelectronic semiconductor chip (11) capable of emitting electromagnetic radiation (15) and a first semiconductor layer (140) of a first conductivity type; a second semiconductor layer (150) of a second conductivity type; a first and a second power distribution layer (180, 160), and comprises a variety of electrical contact elements (20, 21, 22), wherein the first semiconductor layer (140) is arranged above the second semiconductor layer (150), electromagnetic radiation (15) emitted by the optoelectronic semiconductor chip (11) is emitted via a first main surface (110) of the first semiconductor layer (140), the first current distribution layer (180) is arranged on a side of the second semiconductor layer (150) facing away from the first semiconductor layer (140), the multitude of electrical contact elements (20, 21, 22) is suitable to electrically connect the first semiconductor layer (140) with the first current distribution layer (180), the second current distribution layer (160) is electrically connected to the second semiconductor layer (150), and the electrical contact elements (20, 21, 22) comprise a first electrical contact element (20) and a second electrical contact element (21), wherein the first electrical contact element differs from the second electrical contact element. [2] Optoelectronic component (10) according to claim 1, wherein the semiconductor chip (11) comprises a plurality of active areas (142) which are each arranged in a region between the first and second semiconductor layers (140, 150) and each between the electrical contact elements (20, 21, 22), wherein the first electrical contact element (20) is connected to an associated active area (142) via a first resistance value, the second electrical contact element (21) is connected to an associated active area (142) via a second resistance value, and the first resistance value differs from the second resistance value. [3] Optoelectronic component (10) according to one of the preceding claims, wherein the electrical contact elements (20, 21, 22) extend through the second semiconductor layer (150) and are insulated from the material of the second semiconductor layer (150) by an insulating layer (202). [4] Optoelectronic component (10) according to one of the preceding claims, wherein the diameter of the first contact element (20) differs from the diameter of the second contact element (21). [5] Optoelectronic component (10) according to one of the preceding claims, wherein the second current distribution layer (160) is arranged between the first current distribution layer (180) and the second semiconductor layer (150), wherein the electrical contact elements (20, 21, 22) are insulated from the second current distribution layer (180) by an insulating layer (170). [6] Optoelectronic component (10) according to one of the preceding claims, further comprising a contact layer (165) that is suitable for electrically connecting the second current distribution layer (160) to the second semiconductor layer (150). [7] Optoelectronic component (10) according to claim 6, wherein a lateral distance from the contact layer (165) to the first contact element (20) differs from the lateral distance from the contact layer (165) to the second contact element (21). [8] Optoelectronic component (10) according to one of claims 5 to 7, wherein a laterally measured layer thickness of the insulating layer (170) adjacent to the first contact element (20) differs from the laterally measured layer thickness of the insulating layer (170) adjacent to the second contact element (21). [9] Optoelectronic device (10) according to any one of claims 2 to 8, wherein the first current distribution layer (180) is connected to a first terminal area (210) which is arranged on a first main surface (115) of the optoelectronic device (10), wherein the first contact element (20) is arranged closer to the first terminal area (210) than the second contact element (21) and the first resistance value is greater than the second. [10] Optoelectronic component (10) according to claim 9, wherein the sum S1 of lead resistances through the first and second current distribution layer (180, 160) and series resistances through the first and second semiconductor layer (140, 150) for the first electrical contact element (20) and the sum S2 of lead resistances through the first and second current distribution layer (180, 160) and series resistances through the first and second semiconductor layer (140, 150) for the second electrical contact element satisfy the following relationship: |S1-S2| / S1 < 0.

3. [11] Optoelectronic device (10) according to one of the preceding claims, wherein the first current distribution layer (180) is connected to a first connection area (210), the second current distribution layer (160) is connected to a second connection area (211), and the first and second connection areas (210, 211) are each arranged on a first main surface (115) of the optoelectronic device (10). [12] Optoelectronic component (10) according to one of the preceding claims, wherein the optoelectronic semiconductor chip (11) is applied to a heat-dissipating substrate (225) with areas of different thermal conductivity. [13] Optoelectronic component (10) according to claim 12, wherein the second contact element (21) is arranged in a region with better thermal conductivity than the region in which the first contact element (20) is arranged. [14] Optoelectronic component (10) according to claim 12 or 13, wherein the heat-dissipating carrier (225) connects the first current distribution layer (180) to a first connection area (210) and connects the second current distribution layer (160) to a second connection area (211). [15] Method for manufacturing an optoelectronic device comprising forming an optoelectronic semiconductor chip capable of emitting electromagnetic radiation and a first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type; comprising a first and a second current distribution layer, as well as a multitude of electrical contact elements, wherein the first semiconductor layer is arranged above the second semiconductor layer, Electromagnetic radiation emitted by the optoelectronic semiconductor chip is emitted via a first main surface of the first semiconductor layer, the first current distribution layer is located on a side of the second semiconductor layer facing away from the first semiconductor layer, the multitude of electrical contact elements are suitable to electrically connect the first semiconductor layer with the current distribution layer, the multitude of electrical contact elements comprises a first electrical contact element and a second electrical contact element, the second current distribution layer is electrically connected to the second semiconductor layer, wherein the method further comprises setting (S450) a resistance value of a first electrical contact element and a second electrical contact element such that the sum S1 of lead resistances through the first and second contact layers and series resistances through the first and second semiconductor layers for the first electrical contact element and the sum S2 of lead resistances through the first and second contact layers and series resistances through the first and second semiconductor layers for the second electrical contact element satisfy the following relationship: S1-S2 / S1 < 0.

3. [16] Method according to claim 15, wherein the formation of an optoelectronic semiconductor chip the formation (S100) of the first semiconductor layer of the first conductivity type on a growth substrate; the formation (S200) of the second semiconductor layer of the second conductivity type above the first semiconductor layer; the formation (S300) of the second current distribution layer above the second semiconductor layer; the formation (S400) of a large number of electrical contact elements, and The formation (S500) of the first current distribution layer over the second current distribution layer includes, resulting in a layer stack, and the process for manufacturing the optoelectronic component includes the subsequent application (S600) of the layer stack onto a support and the subsequent removal (S700) of the growth substrate. [17] Electrical device (30) comprising the optoelectronic component (10) according to any one of claims 1 to 14. [18] Electrical device (30) according to claim 17, selected from the group consisting of vehicle headlights, projectors and lighting devices.

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