Optoelectronic semiconductor component and method for manufacturing an optoelectronic semiconductor component

Abstract

An optoelectronic semiconductor component (1), comprising a semiconductor body (10) having a contact protrusion (20) and an active region (103) arranged between a first semiconductor region (101) and a second semiconductor region (102), is described herein. The active region (103) is configured to emit electromagnetic radiation through an emission side (10A) of the semiconductor body (10). The semiconductor body (10) extends into the contact protrusion (20) on a back side (10B) facing away from the emission side (10A). The contact protrusion (20) comprises a sidewall contact region (201) and a mirror region (202). The sidewall contact region (201) is arranged between the mirror region (202) and the back side (10B). The mirror region (202) forms an end face of the contact protrusion (20) and is electrically insulated from the semiconductor body (10). Further, a method for manufacturing an optoelectronic semiconductor component (1) is provided. The optoelectronic semiconductor component (1) can be formed as a micro-LED.

Description

[0001] 2023PF01228 January 22, 2025P2023,1296 WO N -1 -Description OPTOELECTRONIC SEMICONDUCTOR COMPONENT AND METHOD FORMANUFACTURING AN OPTOELECTRONIC SEMICONDUCTOR COMPONENT The present application relates to an optoelectronicsemiconductor component and a method for manufacturing anoptoelectronic semiconductor component. In particular, theoptoelectronic semiconductor component is configured to emitelectromagnetic radiation, for example infrared light and / or light that is perceptible to the human eye. It is an object of the present disclosure to provide anoptoelectronic semiconductor component having a higherefficiency. A further object is to provide a method for manufacturing anoptoelectronic semiconductor component having a higherefficiency.These objects are achieved by a component and a methodaccording to the independent patent claims. Advantageousembodiments and further developments of the component and themethod are the subject of the dependent patent claims and will furthermore become apparent from the following description and the figures. According to at least one embodiment of the optoelectronic semiconductor component, the optoelectronic semiconductorcomponent comprises a semiconductor body having a contactprotrusion and an active region arranged between a firstsemiconductor region and a second semiconductor region. Preferably, the semiconductor body is an epitaxially grown2023PF01228 January 22, 2025P2023,1296 WO N -2 -semiconductor element having a plurality of semiconductor layers. The first semiconductor region and the second semiconductor region are in particular regions of different conductivity. For example, the first semiconductor region has a p-conductivity and the second semiconductor region has an n-conductivity or vice versa. According to at least one embodiment of the optoelectronicsemiconductor component, the active region is configured toemit electromagnetic radiation through an emission side ofthe semiconductor body. The active region advantageouslycomprises a pn junction, a double heterostructure, a single quantum well (SQW), or a multiple quantum well (MQW) structure for generating the electromagnetic radiation. According to at least one embodiment of the optoelectronic semiconductor component, the semiconductor body extends into the contact protrusion on a back side facing away from theemission side. In other words, the contact protrusionprotrudes from the back side of the semiconductor body. The back side is preferably oriented parallel to the emissionside of the semiconductor body. In particular, the contactprotrusion forms an aperture at the interface with the back side of the semiconductor body. Preferably, the aperture isoriented parallel to the back side.According to at least one embodiment of the optoelectronicsemiconductor component, the contact protrusion comprises asidewall contact region and a mirror region. The sidewallcontact region is in particular configured to provide an electrical connection of the semiconductor body. The mirror region is preferably configured to reflect electromagnetic radiation emitted by the active region during operation.2023PF01228 January 22, 2025P2023,1296 WO N -3 -According to at least one embodiment of the optoelectronic semiconductor component, the sidewall contact region is arranged between the mirror region and the back side. Preferably, the sidewall contact region extends transverse tothe back side. In particular, the sidewall contact regionextends between the back side of the semiconductor body and the mirror region. According to at least one embodiment of the optoelectronicsemiconductor component, the mirror region forms an end faceof the contact protrusion and is electrically insulated fromthe semiconductor body. In particular, the mirror region hasa reflectivity of at least 70%, preferably of at least 90% and particularly preferably of at least 95% for the electromagnetic radiation emitted by the active region duringoperation. The reflection of the emitted electromagneticradiation can avoid an absorption of the radiation and thus improve an optical efficiency of the optoelectronic semiconductor component. According to at least one embodiment of the optoelectronic semiconductor component, the optoelectronic semiconductorcomponent comprises- a semiconductor body having a contact protrusion and anactive region arranged between a first semiconductor region and a second semiconductor region, wherein- the active region is configured to emit electromagneticradiation through an emission side of the semiconductor body,- the semiconductor body extends into the contact protrusionon a back side facing away from the emission side,- the contact protrusion comprises a sidewall contact regionand a mirror region, wherein2023PF01228 January 22, 2025P2023,1296 WO N -4 -- the sidewall contact region is arranged between the mirrorregion and the back side, and- the mirror region forms an end face of the contactprotrusion and is electrically insulated from the semiconductor body.An optoelectronic semiconductor component described hereinis, inter alia, based on the following considerations: Electrical contacts of optoelectronic semiconductorcomponents that are formed with metal often suffer fromundesirably high optical absorption. To reduce this optical absorption, for example, the surfaces of the metal contactscan be reduced, or large contact structures can be formedwith other materials than metal, for example Indium Tin Oxide(ITO for short). However, smaller contact surfaces canincrease a contact resistance and Indium Tin Oxide for example, still shows a significant optical absorption.The optoelectronic semiconductor component described hereinis, among other things, based on the idea of adding a contactprotrusion having a contact sidewall region and a mirrorregion to a semiconductor body. The mirror region iselectrically insulated and for example curved in the form ofa circular arc and positioned behind an aperture. Due to thehigh optical reflectivity and in particular due to thecurvature of the mirror region, a large fraction of thephotons entering the aperture is reflected back through theaperture towards an emission side. Preferably, the electricalcontacts are formed on the contact sidewall regions, whichare less exposed to photons. Thus, low electrical resistanceand high reflectivity of the contact protrusion can beachieved, even though the actual electrical contact interfacecan have a significant optical absorption.2023PF01228 January 22, 2025P2023,1296 WO N -5 -According to at least one embodiment of the optoelectronicsemiconductor component, the mirror region is curved. Inparticular, the mirror region has a surface which deviates from a planar shape. For example, the mirror region isconvexly or concavely curved. A curved mirror canadvantageously alter a beam shape of radiation impinging onthe mirror region through the aperture. Advantageously thisimproves a proportion of radiation which is reflected back through the aperture towards the emission side of the semiconductor body. According to at least one embodiment of the optoelectronic semiconductor component, the mirror region is curved in the shape of a circular arc having a center point within thesemiconductor body. In other words, the mirror region iscurved in a convex shape as seen from a viewing point outside the semiconductor body. In particular, the shape of a circular arc enables an advantageously high proportion ofradiation to be reflected back into the semiconductor bodyfrom all radiation entering the contact protrusion through the aperture. For example, the center point can be defined by an imaginary intersection point of the sidewall contact regions. The center point of the mirror region is in particular a focal point. According to at least one embodiment of the optoelectronicsemiconductor component, a contact layer is arranged at theback side of the semiconductor body and on the contactprotrusion, wherein the contact layer is electricallyinsulated from the semiconductor body in the mirror regionand the back side by a dielectric layer. In particular, thecontact layer completely covers the back side of the2023PF01228 January 22, 2025P2023,1296 WO N -6 -semiconductor body and the contact protrusion. Preferably, the contact layer is formed with a metal. The dielectriclayer is formed with an electrically insulating material. Forexample, the dielectric layer is formed with silicon oxide or silicon nitride. Preferably, the dielectric layer is radiation permeable for the electromagnetic radiation emitted by the active region during operation. According to at least one embodiment of the optoelectronic semiconductor component, the dielectric layer comprises a plurality of different layers having different refractive indices. In particular, the dielectric layer is formed as a dielectric mirror. A dielectric mirror, in particular aDistributed Bragg Reflector, also known as a DBR mirror, hasa high reflectivity at a resonant frequency. A DBR mirror comprises a plurality of layers with periodically alternating refractive indices. According to at least one embodiment of the optoelectronic semiconductor component, a vertical extension of the contactprotrusion is between and including 0.05 µm and 10 µm,preferably between and including 2 µm to 10 µm. The verticaldirection is oriented parallel to a stacking direction of the semiconductor body. In particular, the vertical direction is oriented parallel to a growth direction in which the semiconductor body was grown epitaxially. According to at least one embodiment of the optoelectronic semiconductor component, a lateral extension of the contactprotrusion is between and including 0.05 µm and 30 µm andpreferably between and including 3 µm to 30 µm. The lateraldirection is oriented perpendicular to the growth direction.2023PF01228 January 22, 2025P2023,1296 WO N -7 -According to at least one embodiment of the optoelectronic semiconductor component, a side angle of the contact protrusion is between and including 15° and 85°, preferablybetween and including 30° to 60°. The side angle is inparticular measured between the back side of the semiconductor body and the side face of the contactprotrusion. A smaller side angle can be helpful to avoid theillumination of the contact side wall regions. According to at least one embodiment of the optoelectronic semiconductor component, the contact protrusion is formed with a semiconductor material comprising a first component and a second component, wherein a concentration of the first component and / or of the second component varies along a growth direction. In particular, the concentration of the first component and / or of the second component varies along a growth direction continuously. Preferably, the semiconductor material comprises Ga as the first component and Al as the second component. In particular, the semiconductor materialis InGaxAl1-xP, wherein 0 ≤ x ≤ 1. Preferably, to avoidoptical absorption, x should be higher than the value corresponding to InGaxAl1-xP having a bandgap higher than the bandgap of the active region. In other words, the value x is advantageously chosen such that the contact protrusion is formed with a semiconductor material comprising a larger bandgap compared to the material of the active region. Alternatively, the semiconductor material comprises Si as the first component and Ge as the second component. In particular, the semiconductor material is SixGe1-x, wherein0 ≤ x ≤ 1. Preferably, to avoid optical absorption, x shouldbe higher than the value corresponding to SixGe1-x having abandgap higher than the bandgap of the active region. A shape2023PF01228 January 22, 2025P2023,1296 WO N -8 -of the contact protrusion can advantageously be formed depending on the variation of concentration of the first component and / or of the second component of the semiconductor material. According to at least one embodiment of the optoelectronic semiconductor component, the semiconductor body and thecontact protrusion are formed with SiGe, a III-V compoundsemiconductor material or a II-VI compound semiconductormaterial, preferably InGaAlP, AlGaN, AlGaAs, InGaAsP orMgZnCdO.A III-V compound semiconductor material comprises at least oneelement from the third main group, such as B, Al, Ga, In, and at least one element from the fifth main group, such as N, P, As. In particular, the term "III-V compound semiconductor material" comprises the group of binary, ternary or quaternary compounds which contain at least one element from the third main group and at least one element from the fifth main group, for example nitride and phosphide compound semiconductors. Such a binary, ternary or quaternary compound can also have, for example, one or more dopants and additional components. A II-VI compound semiconductor material comprises at least oneelement from the second main group or group 12 of the periodictable, such as Be, Mg, Ca, Sr, Zn, Cd, and at least one elementfrom the sixth main group, such as O, S, Se, Te. In particular, the term "II-VI compound semiconductor material" comprises the group of binary, ternary or quaternary compounds which contain at least one element from the third main group and at least one element from the fifth main group, for example oxide, selenide and telluride compound semiconductors. Such a binary,2023PF01228 January 22, 2025P2023,1296 WO N -9 -ternary or quaternary compound can also have, for example, one or more dopants and additional components. According to at least one embodiment of the optoelectronicsemiconductor component, the optoelectronic semiconductorcomponent comprises a plurality of contact protrusions.Preferably, the contact protrusions are distributed evenlyover the back side of the semiconductor body to enable ahomogenous electrical contact. In particular, all contact protrusions comprise the same geometrical shape. According to at least one embodiment of the optoelectronic semiconductor component, the optoelectronic semiconductorcomponent is a micro-LED.As a broad definition, a micro-LED could be seen as any lightemitting diode (LED) - generally not a laser - with aparticularly small size. As a rule - and this is a veryimportant criterion in addition to size - a growth substrateis removed from micro-LEDs, so that typical heights of suchmicro-LEDs are in the range of 1.5 µm to 10 µm, for example.In principle, a micro-LED does not necessarily have to have a rectangular radiation emission surface. Generally, for example, an LED could have a radiation emission surface inwhich, in a plan view of the layers of the layer stack, anylateral extent of the radiation emission surface is less thanor equal to 100 µm or less than or equal to 70 µm.For example, in the case of rectangular micro-LEDs, an edgelength - especially in plan view of the layers of the layerstack - smaller than or equal to 70 µm or smaller than orequal to 50 µm is often cited as a criterion. Mostly, suchmicro-LEDs are provided on wafers with - for the µLED non-2023PF01228 January 22, 2025P2023,1296 WO N -10 -destructively - detachable holding structures. At present,micro-LEDs are mainly used in displays. The micro-LEDs form pixels or subpixels and emit light of a defined color. Small pixel size and a high density with close distances make micro-LEDs suitable, among others, for small monolithic displays for AR applications, especially data glasses. In addition, other applications are being developed, inparticular regarding their use in data communication orpixelated lighting applications. Different ways of spelling micro-LED, e.g. µLED, µ-LED, uLED, u-LED or micro light emitting diode can be found in the relevant literature. A method for manufacturing an optoelectronic semiconductorcomponent is also disclosed. The method for manufacturing anoptoelectronic semiconductor component is particularlysuitable for producing an optoelectronic semiconductorcomponent described herein. This means that all featuresdisclosed in connection with the optoelectronic semiconductorcomponent are also disclosed for the method for manufacturingan optoelectronic semiconductor component and vice versa.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the method comprises a step of providing a growth substrate, a semiconductor body and a gradient layer formed with a semiconductor material comprising a first component and a second component, wherein a concentration of the first component and / or of the second component varies along agrowth direction. The growth substrate is for example formedwith AlGaN.2023PF01228 January 22, 2025P2023,1296 WO N -11 -According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the method comprises a step of structuring the gradient layer via etching into a contact protrusion having a sidewall contactregion and a mirror region. Preferably, the etch method usedhas an etch rate which depends on the concentration of the first component and / or of the second component of the semiconductor material used in the gradient layer. Thus, a shape of the contact protrusion can advantageously be formed depending on the variation of concentration of the first component and / or of the second component of the semiconductor material.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the method comprises a step of depositing a dielectric layer and a contact layer on the semiconductor body, wherein the contact layer is electrically insulated from the semiconductor body in the mirror region by the dielectric layer.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the method comprises the following steps:- providing a growth substrate, a semiconductor body and agradient layer formed with a semiconductor material comprising a first component and a second component, wherein a concentration of the first component and / or of the second component varies along a growth direction,- structuring the gradient layer via etching into a contactprotrusion having a sidewall contact region and a mirror region,2023PF01228 January 22, 2025P2023,1296 WO N -12 -- depositing a dielectric layer and a contact layer on thesemiconductor body, wherein the contact layer is electrically insulated from the semiconductor body in the mirror region by the dielectric layer.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the step of structuring the gradient layer comprises at least two separate etch processes, wherein a first step is carried out via dry etching and a second step is carried out via wetetching. In particular, the first step comprises a mask layerwhich is removed before the second step is carried out. Preferably, the etch method used in the second step has an etch rate which depends on the concentration of the first component and / or of the second component of the semiconductor material used in the gradient layer.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the deposition of the dielectric layer is carried out in a directional deposition method. For example, the deposition ofthe dielectric layer is carried out using an electron beamevaporation or thermal evaporation method. In particular, adirectional deposition method results in different growthrates, depending on surface direction and shadowingstructures. Preferably, the deposition of the dielectriclayer deposits dielectric material on the back side and the mirror region of the contact protrusion. Moreover, the deposition of the dielectric layer avoids a deposition of dielectric material on the sidewall contact regions of the contact protrusion.2023PF01228 January 22, 2025P2023,1296 WO N -13 -According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the deposition of the contact layer is carried out in anisotropic deposition method. For example, the deposition ofthe contact layer is carried out using an electrochemicaldeposition or a chemical vapor deposition method, preferablya low-pressure chemical vapor deposition method. For anisotropic deposition method a deposition rate is inparticular uniform in all directions. Preferably, the material of the contact layer is deposited on the back side, the mirror region and the sidewall contact regions of the contact protrusion.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, after the deposition of the contact layer, the optoelectronic component is annealed to lower an electrical contactresistance. The annealing is in particular achieved byheating the sidewall contact region over a certain period oftime. For example, the sidewall contact region can be heatedby a short laser illumination in a laser annealing process. The annealing can also be achieved by heating the completeoptoelectronic semiconductor component in a furnace.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the semiconductor body is arranged between the growth substrateand the gradient layer. In other words, the gradient layer isgrown on top of the semiconductor body after the deposition of the semiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the2023PF01228 January 22, 2025P2023,1296 WO N -14 -growth substrate is formed with a radiation permeablematerial. In particular, the emission side of thesemiconductor body is oriented towards the growth substrate. The growth substrate is thus arranged downstream of the emission side of the semiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the gradient layer is arranged between the growth substrate andthe semiconductor body. In other words, the gradient layer isdeposited before the semiconductor body. Advantageously, this reduces thermal stress on the sensitive active region in the semiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, the growth substrate is removed before the gradient layer isstructured. Thus, advantageously, there are no requirementsfor an optical permeability of the growth substrate. This enables the use of growth substrates which are not permeable to the electromagnetic radiation emitted by the active region during operation.An optoelectronic semiconductor component described herein isparticularly suitable for the manufacturing of infrared lightemitting components, in particular for micro-LEDs.Further advantages and advantageous designs and further developments of the optoelectronic semiconductor component and the method for manufacturing an optoelectronicsemiconductor component will become apparent from thefollowing exemplary embodiments, which are described below in association with the figures.2023PF01228 January 22, 2025P2023,1296 WO N -15 -In the figures:Figure 1A shows a schematic cross-section of anoptoelectronic semiconductor component describedherein according to a first exemplary embodiment,Figure 1B shows a detailed view of the schematic cross-section of an optoelectronic semiconductor component described herein according to the firstexemplary embodiment,Figures 2A – 2D show schematic top-views of optoelectronicsemiconductor components described herein accordingto different exemplary embodiments,Figures 3A – 3H show schematic cross-sections of anoptoelectronic semiconductor component describedherein in different steps of a method for its manufacturing according to a first exemplary embodiment, andFigures 4A – 4I show schematic cross-sections of anoptoelectronic semiconductor component describedherein in different steps of a method for its manufacturing according to a second exemplaryembodiment. Identical, similar or equivalent elements are marked with the same reference signs in the figures. The figures and the proportions of the elements represented in the figures among each other are not to be considered as true to scale. Rather,2023PF01228 January 22, 2025P2023,1296 WO N -16 -individual elements may be oversized for better representability and / or comprehensibility.Figure 1 shows a schematic cross-section of an optoelectronicsemiconductor component 1 described herein according to afirst exemplary embodiment. The optoelectronic semiconductorcomponent 1 comprises a semiconductor body 10 which isarranged on a carrier 50 via a connection layer 40. The connection layer 40 mechanically and thermally connects the semiconductor body 10 with the carrier 50. The semiconductor body 10 is a monolithic body formed by an epitaxial growth process. The semiconductor body 10 comprises an active region 103 arranged between a first semiconductor region 101 and a second semiconductor region 102. The first semiconductor region 101, the active region 103 and the second semiconductor region 102 are stacked on top of each other along a growth direction Y. The first semiconductor region 101 and the second semiconductor region 102 differ in terms of their type of electrical conductivity. For example, the first semiconductor region 101 has a p-conductivity and the second semiconductor region 102 has an n-conductivity or vice versa. The active region 103 is configured to emit electromagnetic radiation through an emission side 10A of the semiconductor body 10. The active region 103 advantageously comprises a pn junction, a double heterostructure, a single quantum well (SQW), or a multiple quantum well (MQW) structure for generating the electromagnetic radiation. Furthermore, the semiconductor body 10 comprises a contactprotrusion 20 and an electrical contact 90. The semiconductorbody 10 extends into the contact protrusion 20 on a back side 10B of the semiconductor body 10, which is facing away from2023PF01228 January 22, 2025P2023,1296 WO N -17 -the emission side 10A. In other words, the contact protrusion 20 protrudes from the back side 10B of the semiconductor body 10. The back side 10B is preferably oriented parallel to the emission side 10A of the semiconductor body 10. The electrical contact 90 is arranged on the emission side 10A of the semiconductor body 10. Preferably, the electrical contact comprises a radiation permeable electrical conducting layer arranged between the semiconductor body 10 and a metal layer. Alternatively, the electrical contact 90 can also be formed as a contact protrusion 20 described herein. The contact protrusion 20 is formed with a semiconductor material comprising a first component and a second component, wherein a concentration of the first component and / or of the second component varies along the growth direction Y. Preferably, the semiconductor material comprises Ga as the first component and Al as the second component. In particular, the semiconductor material is InGaxAl1-xP, wherein 0 ≤ x ≤ 1. Alternatively, the semiconductor material comprises Si as the first component and Ge as the second component. In particular, the semiconductor material isSixGe1-x, wherein 0 ≤ x ≤ 1. The semiconductor body 10 and thecontact protrusion 20 are formed with SiGe, a III-V compoundsemiconductor material or a II-VI compound semiconductormaterial, preferably InGaAlP, AlGaN, AlGaAs, InGaAsP or MgZnCdO. The contact protrusion 20 comprises a sidewall contact region 201 and a mirror region 202. The sidewall contact region 201 is in particular configured to provide an electrical connection of the semiconductor body 10. In particular, the contact protrusion 20 forms an aperture A at the interface2023PF01228 January 22, 2025P2023,1296 WO N -18 -with the semiconductor body 10, which is oriented parallel tothe back side 10B.A vertical extension 20Y of the contact protrusion 20 isbetween and including 0.05 µm and 10 µm, preferably betweenand including 2 µm to 10 µm. The vertical direction isoriented parallel to the growth direction Y in which thesemiconductor body 10 was grown epitaxially. A lateralextension 20X of the contact protrusion 20 is between andincluding 0.05 µm and 30 µm, preferably between and including3 µm to 30 µm. The lateral direction 20X is orientedperpendicular to the growth direction Y. The sidewall contact region 201 is arranged between the mirror region 202 and the back side 10B. Preferably, the sidewall contact region 201 extends transverse to the backside 10B. In particular, the sidewall contact region 201extends between the back side 10B of the semiconductor body10 and the mirror region 202. The mirror region 202 forms anend face of the contact protrusion 20 and is electricallyinsulated from the semiconductor body 10. The mirror region202 is configured to reflect electromagnetic radiationemitted by the active region 103 during operation. Inparticular, the mirror region 202 has a reflectivity of at least 70%, preferably of at least 90% and particularly preferably of at least 95% for electromagnetic radiationemitted by the active region 103 during operation. Moreover,the mirror region 202 is curved. In particular, the mirror region 202 has a surface which deviates from a planar shape. For example, the mirror region 202 is convexly or concavely curved.2023PF01228 January 22, 2025P2023,1296 WO N -19 -Electromagnetic radiation which is emitted by the activeregion 103 during operation of the semiconductor component 1can enter the contact protrusion 20 through the aperture A, gets reflected by the mirror region 202 of the contact protrusion 20 and gets reflected back in reflected rays R before it reenters the semiconductor body 10 through the aperture A. Thus, an optical absorption of the electromagnetic radiation at the sidewall contact regions 201 can advantageously be reduced or avoided.Moreover, a contact layer 32 is arranged at the back side 10Bof the semiconductor body 10 and on the contact protrusion 20. The contact layer 32 is electrically insulated from the semiconductor body 10 in the mirror region 202 and the back side 10B by a dielectric layer 31. The contact layer 32 completely covers the back side 10B of the semiconductor body10. Furthermore, the contact layer 32 completely covers thecontact protrusion 20. The contact layer 32 is formed with a metal. The dielectric layer 31 is formed with an electrically insulating material. Preferably, the dielectric layer 31 is radiation permeable for the electromagnetic radiation emitted by the active region 103 during operation. For example, the dielectric layer 31 comprises a plurality of different layers having different refractive indices. In particular, the dielectric layer 31 is formed as a dielectric mirror. A dielectric mirror, in particular a DBR mirror, has a high reflectivity at a resonant frequency. A DBR mirror comprises a plurality of layers with periodically alternating refractive indices. The carrier 50 provides a mechanical stability for theoptoelectronic semiconductor component 1. For example, the2023PF01228 January 22, 2025P2023,1296 WO N -20 -carrier 50 is formed with a printed circuit board. Furthermore, the carrier 50 can be configured to provide an electrical and / or thermal connection for the semiconductor body 10. The connection layer 40 is preferably formed with a soldering material. The connection layer 40 has a vertical extension along the growth direction Y which extends at least as far as the vertical extension 20Y of the contact protrusion 20. Figure 1B shows a detailed view of the schematic cross-section of an optoelectronic semiconductor component 1described herein according to the first exemplary embodiment.From the detailed view it becomes apparent that a side angleα of the contact protrusion 20 is between and including 15°and 85°. The side angle α is measured between the back side10B of the semiconductor body 10 and the sidewall contactregion 201 of the contact protrusion 20, which forms a sideface of the contact protrusion 20. Furthermore, the mirror region 202 is curved in the shape of a circular arc having a center point C within the semiconductor body 10. In other words, the mirror region 202 is curved in a convex shape as seen from a viewing point outside the semiconductor body 10. In particular, the shape of a circular arc enables an advantageously high proportionof radiation to be reflected back into the semiconductor body10 from all radiation entering the contact protrusion throughthe aperture A. The center point C is defined by an imaginaryintersection point of the sidewall contact regions 201.2023PF01228 January 22, 2025P2023,1296 WO N -21 -Figures 2A – 2D show schematic top-views of optoelectronicsemiconductor components 1 described herein according todifferent exemplary embodiments. Figure 2A shows an exemplary embodiment which is essentially identical to the first exemplary embodiment shown in Figures 1A and 1B. The exemplary embodiment of the optoelectronicsemiconductor component 1 according to Figure 2A comprises aplurality of contact protrusions 20, in particular five contact protrusions 20. The contact protrusions 20 aredistributed evenly over the back side 10B of thesemiconductor body 10 to enable a homogenous electrical contact. In particular, all contact protrusions 20 have the same geometrical shape. In particular, the contactprotrusions 20 are circular as seen in top view. The dottedlines in Figures 2A to 2D each show a cutting line in which the contact protrusion has a cross-section according to Figure 1B. Figure 2B shows a contact protrusion 20 which is formed in a trench-like manner in the shape of the letter “L”. Figure 2C shows a plurality of contact protrusions 20 which are each formed in a trench-like manner in the shape of straight lines. All contact protrusions 20 are oriented parallel to each other. Figure 2D shows a contact protrusion 20 which is formed in the shape of a closed circle.The shapes of the contact protrusion, however, are notlimited to the shapes explicitly shown here. Thus, the contact protrusion 20 could also have various other shapes.2023PF01228 January 22, 2025P2023,1296 WO N -22 -Figures 3A – 3H show schematic cross-sections of anoptoelectronic semiconductor component 1 described herein indifferent steps of a method for its manufacturing according to a first exemplary embodiment.Figure 3A shows an optoelectronic semiconductor component 1in a first step of a method for its manufacturing. A growth substrate 60, a semiconductor body 10 and a gradient layer 70 are provided. Preferably, the semiconductor body 10 and the gradient layer 70 are formed by an epitaxial deposition method on the growth substrate 60 and deposited along agrowth direction Y. The semiconductor body 10 is grown beforethe gradient layer 70 is deposited. Thus, the semiconductor body 10 is arranged between the growth substrate 60 and thegradient layer 70. The growth substrate 60 is formed with aradiation permeable material. An emission side 10A of thesemiconductor body 10 is oriented towards the growth substrate 60. The growth substrate 60 is thus arranged downstream of the emission side 10A of the semiconductor body 10. The gradient layer 70 is formed with a semiconductor material comprising a first component and a second component, wherein a concentration of the first component and / or of the secondcomponent varies along the growth direction Y. Preferably,the semiconductor material comprises Si as the first component and Ge as the second component. In particular, thesemiconductor material is SixGe1-x, wherein 0 ≤ x ≤ 1. A shapeof the contact protrusion 20 can advantageously be formed depending on the variation of concentration of the first component and / or of the second component of the semiconductor material. A gradient layer 70 formed with SiGe in varying2023PF01228 January 22, 2025P2023,1296 WO N -23 -concentrations can produce unwanted lattice mismatch. Thus, it is advantageous to form the semiconductor body 10 before the gradient layer 70 is grown.Figure 3B shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. Thegradient layer 70 is structured via etching. A first step iscarried out via dry etching after a mask layer 80 is deposited on a side of the gradient layer facing away from the semiconductor body 10.Figure 3C shows the optoelectronic semiconductor component 1after the dry etching process. Part of the gradient layer 70is removed, forming a mesa-like shape in the gradient layer70. Preferably, dry etching is carried out until it stops atthe depth of the semiconductor body 10. For example, the dryetching method can use detection of the differentcompositions of the gradient layer 70 and the semiconductorbody 10 to detect the etch depth.Figure 3D shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. The masklayer 80, which was used for the first step, is removed.Figure 3E shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. The remaining parts of the gradient layer 70 are formed into acontact protrusion 20 having a sidewall contact region 201and a mirror region 202 in a second step, which is carriedout via wet etching. The etch method used has an etch ratewhich depends on the concentration of the first component and / or of the second component of the semiconductor material used in the gradient layer 70. Thus, a shape of the contact2023PF01228 January 22, 2025P2023,1296 WO N -24 -protrusion 20 can advantageously be formed depending on the variation of concentration of the first component and / or of the second component of the semiconductor material.Figure 3F shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. Adielectric layer 31 is deposited on the semiconductor body10. The dielectric layer 31 is formed with an electrically insulating material. Preferably, the dielectric layer 31 is radiation permeable for the electromagnetic radiation emitted by the active region 103 during operation. The deposition of the dielectric layer 31 is carried out in a directional deposition method. In particular, a directional depositionmethod results in the formation of slightly differentdeposits on the sidewalls of a trench as compared to thebottom of the trench or a hidden undercut. Preferably, thedeposition of the dielectric layer 31 deposits dielectric material on the back side 10B and the mirror region 202 of the contact protrusion 20. Moreover, the deposition of the dielectric layer 31 avoids deposition of dielectric material on the sidewall contact regions 201 of the contact protrusion 20.Figure 3G shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. A contact layer 32 is deposited on the semiconductor body 10.The contact layer 32 is arranged at the back side 10B of thesemiconductor body 10 and on the contact protrusion 20, wherein the contact layer 32 is electrically insulated from the semiconductor body 10 in the mirror region 202 and theback side 10B by the dielectric layer 31. In particular, thecontact layer 32 completely covers the back side 10B of the semiconductor body 10 and the contact protrusion 20.2023PF01228 January 22, 2025P2023,1296 WO N -25 -Preferably, the contact layer 32 is formed with a metal. The deposition of the contact layer 32 is carried out in an isotropic deposition method. For an isotropic depositionmethod a deposition rate is in particular uniform in alldirections. Preferably, the material of the contact layer 32 is deposited on the back side 10B, the mirror region 202 and the sidewall contact regions 201 of the contact protrusion 20.Figure 3H shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. Afterthe deposition of the contact layer 32, the optoelectroniccomponent 1 is annealed to lower an electrical contactresistance. The annealing is in particular achieved byheating the sidewall contact region 201 over a certain periodof time to form annealing regions 320. For example, thesidewall contact region 201 can be heated by a short laserillumination in a laser annealing process. Thus, anelectrical resistance of the sidewall contact region 201 can be reduced.Figures 4A – 4I show schematic cross-sections of anoptoelectronic semiconductor component 1 described herein indifferent steps of a method for its manufacturing accordingto a second exemplary embodiment.Figure 4A shows an optoelectronic semiconductor component 1in a first step of a method for its manufacturing. A growth substrate 60, a gradient layer 70 and a semiconductor body 10 are provided. Preferably, the semiconductor body 10 and the gradient layer 70 are formed by an epitaxial deposition method on the growth substrate 60 and deposited along a growth direction Y. The gradient layer 70 is grown before the2023PF01228 January 22, 2025P2023,1296 WO N -26 -semiconductor body 10 is deposited. Thus, the gradient layer 70 is arranged between the growth substrate 60 and thesemiconductor body 10. Advantageously, this reduces thermalstress on the sensitive active region 103 in the semiconductor body 10. This method is particularly preferable for the use of AlGaN as a semiconductor material for the semiconductor body 10, as this material is particularly sensitive to thermal stress.The growth substrate 60 can also be formed with a radiationimpermeable material. A back side 10B of the semiconductorbody 10 is oriented towards the growth substrate 60. Thus,the growth substrate 60 is arranged remote of an emissionside 10A of the semiconductor body 10.Figure 4B shows the optoelectronic semiconductor component 1in a further step of a method for its manufacturing. The growth substrate 60 is removed from the semiconductorcomponent 1. This enables the manufacture of a particularlysmall semiconductor body 10 having a smaller height compared to components with an attached growth substrate 60. Thus, this method is suitable for the manufacture of micro-LEDs. Figures 4C to 4I show essentially the same method steps as do Figures 3B to 3H. The invention described herein is not limited by the description given with reference to the exemplary embodiments. Rather, the invention encompasses any novel feature and any combination of features, including in particular any combination of features in the claims, even if this feature or this combination is not itself explicitly indicated in the claims or exemplary embodiments.2023PF01228 January 22, 2025P2023,1296 WO N -27 -This patent application claims the priority of the German patent application 102024102033.4, the disclosure content of which is hereby incorporated by reference.

[0002] 2023PF01228 January 22, 2025P2023,1296 WO N -28 -References1 optoelectronic semiconductor component10 semiconductor body101 first semiconductor region102 second semiconductor region103 active region20 contact protrusion201 sidewall contact region202 mirror region31 dielectric layer32 contact layer320 annealing region40 connection layer50 carrier60 substrate70 gradient layer80 mask layer90 electrical contactR reflected raysA aperture10A emission side of the semiconductor body10B back side of the semiconductor body20Y vertical extension of the contact protrusion20X lateral extension of the contact protrusionα side angle of the contact protrusionC center pointX lateral directionY growth direction

Claims

2023PF01228 January 22, 2025P2023,1296 WO N -29 -Claims1. Optoelectronic semiconductor component (1), comprising- a semiconductor body (10) having a contact protrusion (20)and an active region (103) arranged between a firstsemiconductor region (101) and a second semiconductor region(102), wherein- the active region (103) is configured to emitelectromagnetic radiation through an emission side (10A) of the semiconductor body (10),- the semiconductor body (10) extends into the contactprotrusion (20) on a back side (10B) facing away from theemission side (10A),- the contact protrusion (20) comprises a sidewall contactregion (201) and a mirror region (202), wherein- the sidewall contact region (201) is arranged between themirror region (202) and the back side (10B), and- the mirror region (202) forms an end face of the contactprotrusion (20) and is electrically insulated from thesemiconductor body (10).

2. Optoelectronic semiconductor component (1) according tothe preceding claim, wherein- the mirror region (202) is curved.

3. Optoelectronic semiconductor component (1) according tothe preceding claim, wherein- the mirror region (202) is curved in the shape of acircular arc having a center point (C) within the semiconductor body (10).

4. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein2023PF01228 January 22, 2025P2023,1296 WO N -30 -- a contact layer (32) is arranged at the back side (10B) ofthe semiconductor body (10) and on the contact protrusion(20), wherein the contact layer (32) is electricallyinsulated from the semiconductor body (10) in the mirrorregion (202) and the back side (10B) by a dielectric layer(31).

5. Optoelectronic semiconductor component (1) according tothe preceding claim, wherein- the dielectric layer (31) comprises a plurality ofdifferent layers having different refractive indices.

6. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein- a vertical extension (20Y) of the contact protrusion (20)is between and including 0.05 µm and 10 µm, preferablybetween and including 2 µm to 10 µm.

7. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein- a lateral extension (20X) of the contact protrusion (20) isbetween and including 0.05 µm and 30 µm, preferably betweenand including 3 µm to 30 µm.

8. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein- a side angle (α) of the contact protrusion (20) is betweenand including 15° and 85° and preferably between andincluding 30° to 60°.

9. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein- the contact protrusion (20) is formed with a semiconductor2023PF01228 January 22, 2025P2023,1296 WO N -31 -material comprising a first component and a second component,wherein a concentration of the first component and / or of the second component varies along a growth direction (Y).

10. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein- the semiconductor body (10) and the contact protrusion (20)are formed with SiGe, a III-V compound semiconductor materialor a II-VI compound semiconductor material, preferablyInGaAlP, AlGaN, AlGaAs, InGaAsP or MgZnCdO.

11. Optoelectronic semiconductor component (1) according toone of the preceding claims, comprising a plurality of contact protrusions (20).

12. Optoelectronic semiconductor component (1) according toone of the preceding claims, wherein the optoelectronicsemiconductor component is a micro-LED.

13. Method for manufacturing an optoelectronic semiconductorcomponent (1), comprising the following steps:- providing a growth substrate (60), a semiconductor body(10) and a gradient layer (70) formed with a semiconductormaterial comprising a first component and a second component, wherein a concentration of the first component and / or of the second component varies along a growth direction (Y),- structuring the gradient layer (70) via etching into acontact protrusion (20) having a sidewall contact region (201) and a mirror region (202),- depositing a dielectric layer (31) and a contact layer (32)on the semiconductor body (10), wherein the contact layer (32) is electrically insulated from the semiconductor body (10) in the mirror region (202) by the dielectric layer (31).2023PF01228 January 22, 2025P2023,1296 WO N -32 -14. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to the preceding claim, wherein- structuring the gradient layer (70) comprises at least twoseparate etch processes, wherein a first step is carried out via dry etching and a second step is carried out via wet etching.

15. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims,wherein- the deposition of the dielectric layer (31) is carried outin a directional deposition method.

16. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims,wherein- the deposition of the contact layer (32) is carried out inan isotropic deposition method.

17. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims,wherein- after the deposition of the contact layer (32), theoptoelectronic component (1) is annealed to lower anelectrical contact resistance.

18. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims,wherein- the semiconductor body (10) is arranged between the growthsubstrate (60) and the gradient layer (70).2023PF01228 January 22, 2025P2023,1296 WO N -<sub>33 -19. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of preceding claims 12 to 16,wherein- the gradient layer (70) is arranged between the growthsubstrate (60) and the semiconductor body (10).

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