Method for manufacturing an optoelectronic semiconductor component

Abstract

A method for manufacturing an optoelectronic semiconductor component (1) is described herein. The method comprises the step of providing a semiconductor body (10) having an active region (101) configured to emit an electromagnetic radiation through an emission surface (10A) on a first side of the semiconductor body (10). Further, a photosensitive material (20) is applied on the first side of the semiconductor body (10) to form a cavity (200) laterally surrounding the emission surface (10A). The method comprises a further step of at least partially filling the cavity (200) with a wavelength converter material (30) comprising converter particles and a matrix material by using a screen printing mask (40) defining a printing region (401).

Description

[0001] - 1 –Description METHOD FOR MANUFACTURING AN OPTOELECTRONIC SEMICONDUCTOR COMPONENT The present application relates to a method for manufacturing an optoelectronic semiconductor component. In particular, the optoelectronic semiconductor component is configured to emit and / or detect electromagnetic radiation, for example light that is perceptible to the human eye. It is an object of the present disclosure to provide a method for manufacturing an optoelectronic semiconductor component having improved optical characteristics and efficiency.This object is achieved by a method according to theindependent patent claim. Advantageous embodiments and further developments of the method are the subject of thedependent patent claims and will furthermore become apparentfrom the following description and the figures.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, themethod comprises a step of providing a semiconductor bodyhaving an active region configured to emit an electromagnetic radiation through an emission surface on a first side of the semiconductor body. The semiconductor body is in particular formed as a monolithic body comprising several epitaxially grown layers of different compositions. For example, the semiconductor body comprises a first region of a first conductivity and a second region of a second conductivity, wherein the active- 2 –region is arranged between the first region and the second region. The first conductivity type is, for example, an n-type conductivity and the second conductivity type is, for example, a p-type conductivity or vice versa. For example, the first region is doped with a first doping material andthe second region is doped with a second doping material. Thefirst and / or second region can also comprise a plurality of doping materials. The active region advantageously comprises a pn junction, a double heterostructure, a single quantum well (SQW), or a multiple quantum well (MQW) structure for generating or detecting electromagnetic radiation. The radiation is in particular emitted by the semiconductor body through the emission surface. The emission surface is preferably oriented parallel to a main plane of extension of the semiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, themethod comprises a step of applying a photosensitive materialon the first side of the semiconductor body to form a cavity laterally surrounding the emission surface. The photosensitive material is in particular a photoresist material. For example, the photosensitive material is formedwith an organic material such as a polymer. Thephotosensitive material can be formed with an epoxy. Inparticular, the photosensitive material comprises thefollowing components: a resin that provides physical- 3 –properties such as adhesion and / or chemical resistance, asensitizer which has a photoactive compound. Such a material is called a dry resist. Alternatively, if the photosensitivematerial further comprises a solvent which keeps the resistliquid, it is a so called wet resist. Moreover, the photosensitive material can be formed as apositive resist, wherein light will weaken the resist andcreate a hole in the illuminated regions, or as a negativeresist, wherein light will strengthen the resist and createan etch resistant mask in the illuminated regions.The cavity is formed by the photosensitive material on the side of the semiconductor body on which the emission surface is arranged. In particular, the photosensitive material laterally delimits the cavity. Preferably, the photosensitive material is shaped in the form of a dam structure surrounding the emission surface.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, themethod comprises a step of at least partially filling thecavity with a wavelength converter material comprisingconverter particles and a matrix material by using a screenprinting mask defining a printing region. The cavity is inparticular configured to delimit a lateral extension of the wavelength converter material. In particular, the wavelengthconverter material has a filling degree of at least 50 wt%,preferably of at least 60 wt% and particularly preferably ofat least 70 wt%. The filling degree is to be understood as aweight ratio of the converter particles in the wavelength converter material comprising converter particles and matrix material.- 4 –The wavelength converter material is configured to at least partially convert an electromagnetic radiation of a first wavelength which is entering the converter material into electromagnetic radiation of a second wavelength. In particular, the second wavelength is greater than the first wavelength. Preferably, the wavelength converter material emits electromagnetic radiation of the first and / or second wavelength. The wavelength converter material preferably comprisesconverter particles. The converter particles are particularlyformed with a phosphor, for example a ceramic phosphor and / ora quantum dot phosphor. The converter particles preferablycomprise a crystalline, for example ceramic, host lattice into which foreign elements are introduced as activator elements. The phosphor may be a ceramic material, for example. For example, a combination of different phosphor materials can be used as a conversion element. Preferably, the ceramic phosphor comprises a garnet phosphor. Particularly preferably, the garnet phosphor is a YAGphosphor having the chemical formula Y3(Al,Ga)5O12:Ce or aLUAG phosphor having the chemical formula Lu3(Al,Ga)5O12:Ce. Furthermore, the ceramic phosphor may also comprise a nitride and / or an oxynitride phosphor. The nitride or oxynitride phosphor may be, for example, an alkaline earth silicon (oxy- )nitride, an oxynitride, an aluminum oxynitride, a silicon nitride or a Sialon. Preferably, the ceramic phosphors are selected from the following group:- 5 –Ce3+doped garnets such as YAG and LuAG, for example (Y,Lu,Gd,Tb)3(Al1-x,Gax)5O12:Ce3+; Eu2+ / and or Ce3+doped nitrides, such as (Ca,Sr)AlSiN3:Eu2+ / Ce3+, Sr(Ca,Sr)Si2Al2N6:Eu2+ / Ce3+(SCASN), (Sr,Ca)AlSiN3*Si2N2O:Eu2+ / Ce3+, (Ca,Ba,Sr)2Si5N8:Eu2+ / Ce3+, SrLiAl3N4:Eu2+ / Ce3+, SrLi2Al2O2N2:Eu2+ / Ce3+, (Ca,Sr)Al(1-3)Si(1+x)N3:Eu / Ce (x = 0.2 – 0.5 + 2+ 3+4x / 3 ), (La,Y)3Si6N11:Ce ; Eu / Cedoped sulphides, (Ba,Sr,Ca)Si2O2N2:Eu2+ / Ce3+, SiAlONs, nitrido- orthosilicates (for example AE2-x-aRExEuaSi1-yO4-x-2yNx), orthosilicates (Ba,Sr,Ca)2SiO4:Eu2+; chlorosilicates (e.g. Ca8Mg(SiO4)4Cl2:Eu2+); Mn4+doped fluorides, for example (K,Na)2(Si,Ti)F6:Mn4+; Eu2+or Ce3+doped litho-silicates, such as (Li,Na,K,Rb,Cs)(Li3SiO4):E with E as Eu2+, Ce3+, or (Sr,Li)Li3AlO4:Eu2+ / Ce3+or SrLi3AlO4:Eu2+ / Ce3+. Particularly preferably, the ceramic phosphors are selected from the following group:Ce3+ doped garnets such as YAG and LuAG, for example(Y,Lu,Gd,Tb) (Al ,Ga ) O :Ce3+; Ce3+3 1-x x 5 12 doped nitrides, such as(Ca,Sr)AlSiN3:Ce3+, Sr(Ca,Sr)Si2Al2N6:Ce3+(SCASN), (Sr,Ca)AlSiN3*Si2N2O:Ce3+, (Ca,Ba,Sr)2Si5N8:Ce3+, SrLiAl3N4:Ce3+,SrLi 3+ 3+2Al2O2N2:Ce ; Ce doped nitrides, for example (Ca,Sr)Al(1-4x / 3)Si(1+x)N3:Ce; (x = 0.2 – 0.5),(La,Y)3Si6N11:Ce3+;(Ba,Sr,Ca)Si2O2N2:Eu2+, SiAlONs, nitrido-orthosilicates (for example AE2-x-aRExEuaSi1-yO4-x-2yNx),orthosilicates (Ba,Sr,Ca)2SiO4:Eu2+; chlorosilicates (e.g.Ca8Mg(SiO4)4Cl2:Eu2+); or Ce3+ doped litho-silicates, such as(Li,Na,K,Rb,Cs)(Li SiO ):E wi 2+ 3+3 4 th E as Eu , Ce , or(Sr,Li)Li AlO :Eu2+ / Ce3+ or SrLi A 2+ 3+3 4 3 lO4:Eu / Ce .Other possible materials for the phosphors include, in particular, the following aluminum-containing and / or silicon- containing phosphor particles:- 6 –(Ba1-x-ySrxCay)SiO4:Eu2+ (0 ^ x ^ 1, 0 ^ y ^ 1), (Ba1-x-ySrxCay)3SiO5:Eu2+ (0 ^ x ^ 1, 0 ^ y ^ 1), Li2SrSiO4:Eu2+, Oxo-nitrides such as (Ba1-x-ySrxCay)Si2O2N2:Eu2+ (0 ^ x ^ 1; 0 ^ y ^1), SrSiAl O N :Eu2+, Ba Ca Si 2+2 3 2 4-x x 6ON10:Eu (0 ^ x ^ 1), (Ba1-Sr )Y Si Al O N :E 2+ 2+x x 2 2 2 2 5 u (0 ^ x ^ 1), SrxSi(6-y)AlyOyN(8-y):Eu (0.05^ x ^ 0.5; 0.001 ^ y ^ 0.5), Ba Si O N :Eu2+, Si Al O N :Eu2+3 6 12 2 6-z z z 8-z(0 ^ z ^ 0.42), MxSi12-m-nAlm+nOnN16-n:Eu2+ (M = Li, Mg, Ca, Y; x= m / v; v = valence of M, x ^ 2), M 3+xSi12-m-nAlm+nOnN16-n:Ce , AE2-x-aRExEuaSi1-yO4-x-2yNx(AE = Sr, Ba, Ca, Mg; RE = rare earth elements), AE2-x-aRExEuaSi1-yO4-x-2yNx (AE = Sr, Ba, Ca, Mg; RE =rare earth elements), or nitrides such as (La,Y) 3+3Si6N11:Ce ,(Ba Sr Ca ) Si N :Eu2+, (Ca Sr Ba )A 2+1-x-y x y 2 5 8 1-x-y x y lSiN3:Eu (0 ^ x ^ 1; 0^ y ^ 1), Sr(Sr 2+1-xCax)Al2Si2N6:Eu (0 ^ x ^ 0.2), Sr(Sr1-Ca )A 3+ 2+x x l2Si2N6:Ce (0 ^ x ^ 0.2) SrAlSi4N7:Eu , (Ba1-x-Sr Ca )SiN :Eu2+ (0 ^ x ^ 1; 0 ^ y 3+y x y 2 ^ 1), (Ba1-x-ySrxCay)SiN2:Ce(0 ^ x ^ 1; 0 ^ y ^ 1), (Sr1-xCax)LiAl3N4:Eu2+ (0 ^ x ^ 1),(Ba x-ySrxCay)Mg2Al 2+1- 2N4:Eu (0 ^ x ^ 1; 0 ^ y ^ 1), (Ba1-x-Sr Ca )Mg3S 2+y x y iN4:Eu (0 ^ x ^ 1; 0 ^ y ^ 1).In particular, the wavelength converter material is providedin the form of a slurry. The form of a slurry facilitates the application of the wavelength converter material in a defined way. For example, the matrix material is a polysiloxane or anepoxy which can be cured after being applied. Preferably, thematrix material comprises or is formed from a silicone, an epoxy, or a mixture of these materials. The screen printing mask is for example formed with a mesh.Partial areas of the screen printing mask are madeimpermeable to the wavelength converter material, for example- 7 –by a blocking stencil or a mask formed with photosensitivematerial, to define the printing region. In particular, theprinting region is located in areas of the screen printing mask which are not blocked and thus permeable to the wavelength converter material.Subsequently, a blade or squeegee can be moved across thescreen printing mask to fill the open mesh apertures withwavelength converter material, and a reverse stroke thencauses the screen printing mask to touch the semiconductorbody underneath the screen printing mask momentarily along aline of contact. Alternatively, the screen printing masktouches the semiconductor body underneath the screen printingmask momentarily along a line of contact during the forwardstroke. This causes the wavelength converter material to wetthe semiconductor body and be pulled out of the meshapertures as the screen printing mask springs back after theblade has passed. The use of the screen printing mask enables a precise application of wavelength converter material to the cavity defined on the emission surface of the semiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, themethod comprises the steps of:- providing a semiconductor body having an active regionconfigured to emit an electromagnetic radiation through an emission surface on a first side of the semiconductor body,- applying a photosensitive material on the first side of thesemiconductor body to form a cavity laterally surrounding the emission surface,- 8 –- at least partially filling the cavity with a wavelengthconverter material comprising converter particles and amatrix material by using a screen printing mask defining a printing region.A method for manufacturing an optoelectronic semiconductorcomponent described herein is, inter alia, based on thefollowing considerations: For manufacturing an optoelectronicsemiconductor component emitting electromagnetic radiation ofcertain colors like "amber" for example, a high conversionratio is advantageous. The conversion ratio refers to a ratio of electromagnetic radiation having a first wavelengthentering the converter material and the convertedelectromagnetic radiation having a second wavelength. In particular for cost-effective manufacturing, a simultaneous process on a wafer level is preferable, for example whereinthe wavelength converter material is simultaneously appliedon a plurality of optoelectronic semiconductor components connected together in a wafer compound. However, theapplication of wavelength converter material on a wafer levelworks particularly well for thin layers which allow for a sufficient control of the lateral extension of the applied converter material. On the other hand, a thin layer ofwavelength converter material makes it difficult to achieve asufficiently high conversion ratio.The method for manufacturing an optoelectronic semiconductorcomponent described herein, inter alia, makes use of the ideaof using a photosensitive material to define a cavity intowhich the wavelength converter material is filled and ofusing a screen printing method to precisely apply the wavelength converter material into the cavity. Furthermore,the process may be repeated to add a second layer of- 9 –wavelength converter material to enable an emission of awider variety of colors. Moreover, a filling degree of thewavelength converter material can be increased by acentrifugal process. Furthermore, anti-cracking robustness isstrongly dependent on the filling degree because matrixmaterial can show significant shrinking rates after curing,which can cause cracks in the converter material.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, thesemiconductor body comprises a bondpad region which is located adjacent to the cavity and is thus not filled withthe converter material. The bondpad region in particularcomprises a metal element configured to inject chargecarriers into the semiconductor body. The use of a screenprinting technique in combination with a photosensitivematerial can advantageously restrict the application of wavelength converter material to the cavity above the emission surface and spare other parts of the chip surface inwhich for example bondpad regions are arranged. Thus, thebondpad region remains accessible for probing. Probing inparticular means the electrical connection of the semiconductor body in order to measure optical characteristics such as a color point of an electromagnetic radiation emitted by the semiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, alateral extension of the printing region is smaller than alateral extension of the cavity. In particular, a lateralextension of the printing region is at least 10 µm smaller,preferably at least 20 µm and particularly preferably atleast 30 µm smaller than the lateral extension of the cavity.- 10 –Advantageously, this reduces the precision required toposition the printing region of the mask relative to thecavity.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, acentrifugal process laterally distributes the wavelengthconverter material evenly in the cavity. In particular, adirection of a centripetal acceleration is oriented parallel to a normal vector of the optoelectronic semiconductor component. In other words, the centrifugal process is configured in such a way that a centripetal acceleration is aligned in a direction parallel to a stacking direction ofthe semiconductor body. The stacking direction refers to adirection in which the different semiconductor layers of the semiconductor are epitaxially grown above each other.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, thecentrifugal process causes a sedimentation in the wavelengthconverter material. Depending on a duration of thecentrifugal process and the amount of centripetal acceleration, the converter particles and the matrix materialof the wavelength converter material will be separated fromeach other. In particular, the centrifugal process causes asedimentation of wavelength converter particles towards theemission surface of the semiconductor body, because theconverter particles have a higher specific weight than thematrix material. Sedimentation of the phosphor particles canbe done even with very high filling degrees in the wavelengthconverter material of 60 wt% or more.- 11 –A subsequent removal of unfilled matrix material on the upperpart of the wavelength converter material layer can furtherincrease the filling degree to over 90 wt%. Advantageously, sedimentation leads to a thinner wavelength convertermaterial and inter alia contributes to a higher contrast, ahigher thermal conductivity, higher efficacy, and thepossibility to remove the remaining unfilled matrix materialabove the sedimented phosphors. If a distance betweendirectly neighboring phosphor particles is very small,cracking and aging processes are reduced and the convertermaterial can withstand a lifetime of as much as 6000 hourswithout any shift of a color point. A centrifugalsedimentation together with a grinding process can reduce athickness of the wavelength converter material to at most15 µm.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, thematrix material is partially removed from the wavelengthconverter material by a solvent or plasma matrix materialremoval. The removal of matrix material can avoid anynegative influences by the matrix materials such as asubsequent formation of cracks in the converter material, forexample.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, alateral extension of the printing region is equal to a lateral extension of the semiconductor component and extendsbeyond the bondpad region. This enables a particularly evendistribution of wavelength converter material.- 12 –According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, thestep of applying the converter material is repeated and asecond layer of converter material is subsequently depositedon top of a first layer of converter material. The secondlayer can be applied by using a screen printing mask, stencilprinting, jetting, dispensing, mask spray coating or water screen printing.Such a multilayered converter material enables enhancedspectral characteristics and can lead to higher efficacy.Application and curing of several thin layers of wavelengthconverter material can advantageously reduce the formation ofcracks.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, thesemiconductor body is stored under a controlled atmosphere between the steps of applying the different layers ofconverter material without curing. In particular, theconverter material is not subjected to thermal, chemical and / or optical curing conditions between the steps ofapplying the different layers of converter material. If keptin a controlled atmosphere, preferably a protectiveatmosphere having reduced moisture, for example, a colorcorrection can be done after probing the semiconductor body.The measured color point of emitted electromagnetic radiationcan be manipulated by applying dry phosphor, phosphor insolvent / light oil or phosphor in siloxane to thesemiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component,- 13 –spectral emission characteristics of the semiconductor component are measured after applying the converter material by contacting the bondpad region with a probing needle.Advantageously, probing after the screen printing process isenabled because the lithographically defined opening of thewavelength converter material in the bondpad region can beused for a probing needle to electrically contact thesemiconductor body.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, theconverter material is partially removed by using one of thefollowing methods: polishing, grinding. A removal bypolishing or grinding can precisely adjust the color point of emitted electromagnetic radiation.According to at least one embodiment of the method formanufacturing an optoelectronic semiconductor component, aforced-siloxane crack-in is performed on the convertermaterial by exposing the converter material to UVC radiation.In particular, the illumination with UVC radiation is performed such that the semiconductor body emits an electromagnetic radiation having a desired color point. Furthermore, a method for manufacturing a plurality of optoelectronic semiconductor components is disclosed.According to at least one embodiment of the method formanufacturing a plurality of optoelectronic semiconductorcomponents, the method steps of the preceding embodiments arecarried out on a wafer level and the semiconductor componentsare subsequently singulated. Advantageously, this enables toperform the steps of manufacturing simultaneously on a- 14 –plurality of semiconductor bodies. Thus, the effective costs for manufacturing a semiconductor body are reduced.According to at least one embodiment of the method formanufacturing a plurality of optoelectronic semiconductorcomponents, the bondpad regions are exposed before thesemiconductor components are singulated. In particular, thebondpad regions are exposed by a mechanical process. Byexposing the bondpad regions before the semiconductorcomponents are singulated, a photosensitive material arranged on the bondpad regions is accessible and can thus be removed. The accessible bondpad regions enable a process of electrically contacting each semiconductor body using a probing needle before the singulation.According to at least one embodiment of the method formanufacturing a plurality of optoelectronic semiconductorcomponents, the semiconductor components are singulated usinga sawing process. Sawing is an advantageously widespread andfast method for singulating semiconductor components.According to at least one embodiment of the method formanufacturing a plurality of optoelectronic semiconductor components, the semiconductor components are singulated usinga stealth dicing process. In particular, a laser focus islocated internally of the semiconductor components and formsa starting point for cracking inside the material. Advantageously, the outer surface remains intact.According to at least one embodiment of the method formanufacturing a plurality of optoelectronic semiconductor components, the semiconductor components are singulated usinga laser ablation process. In particular, the semiconductor- 15 –components are singulated using laser dicing. For example, the semiconductor components are singulated using a combined scribe and break process, wherein a laser ablation is used to define a separation line and mechanical force is used to singulate the devices along the separation line.An optoelectronic semiconductor component manufactured in aprocess described herein is particularly suitable for use in high-power converted light emitting diodes for the visible spectrum. Preferably, the semiconductor component describedherein is used in automotive applications, lighting,projection devices or signal devices.Moreover, the method is in particular suitable formanufacturing micro-LEDs. For µLEDs with sizes of40 µm x 80 µm, a thickness of the converter material of morethan 30 µm can cause bending due to thermal expansion of thematrix material. Thus, a reduction of a thickness of theconverter material to an absolute minimum is advantageous toget efficient, low complex and reliable micro-LEDs.As a broad definition, a micro-LED could be seen as any lightemitting diode (LED) - generally not a laser - with aparticularly small size. A growth substrate can be removedfrom micro-LEDs, so that typical heights of such micro-LEDsare in the range of 1.5 µm to 10 µm, for example. Inprinciple, 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 in which, in plan view of the layers of the layer stack, any lateral extent of the radiation emission surface is less thanor equal to 100 µm or less than or equal to 70 µm.- 16 –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-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, in particular regarding the use in data communication or pixelated 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 therelevant literature. According to at least one embodiment, the optoelectronic semiconductor component is a micro-LED. Further advantages and advantageous designs and further developments of the optoelectronic semiconductor component will become apparent from the following exemplary embodiments, which are described below in association with the figures. In the figures:Figures 1A to 1E show schematic cross-sectional views of anoptoelectronic semiconductor component described- 17 –herein according to different steps of a method for its manufacturing according to a first exemplaryembodiment,Figures 2A to 2C show schematic cross-sectional views of anoptoelectronic semiconductor component described herein according to different steps of a method for its manufacturing according to a second exemplaryembodiment,Figures 3A, 3B, 4A, 4B, 5A, 5B, 6A and 6B show schematic topviews and schematic cross-sectional views of anoptoelectronic semiconductor component described herein according to different steps of a method for its manufacturing according to a third exemplaryembodiment,Figures 7A to 7G show schematic cross-sectional views of anoptoelectronic semiconductor component described herein according to different steps of a method for its manufacturing according to a fourth exemplaryembodiment, andFigures 8A to 8D show schematic cross-sectional views of anoptoelectronic semiconductor component described herein according to different steps of a method for its manufacturing according to a fifth 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,- 18 –individual elements may be oversized for better representability and / or comprehensibility.Figures 1A to 1E show schematic cross-sectional views of anoptoelectronic semiconductor component 1 described hereinaccording to different steps of a method for itsmanufacturing according to a first exemplary embodiment.Figure 1A shows a schematic cross-sectional view of a wafer 2 comprising a plurality of optoelectronic semiconductorcomponents 1 in a first step of a method for theirmanufacturing according to a first exemplary embodiment. Every semiconductor component 1 of the wafer 2 comprises a semiconductor body 10 having an active region 101 and a bondpad region 102. The active region 101 is configured to emit an electromagnetic radiation through an emission surface 10A on a first side of the semiconductor body 10. The semiconductor body 10 is in particular formed as a monolithic body comprising several epitaxially depositedlayers of different compositions. The semiconductor body 10comprises a first region 103 of a first conductivity and a second region 104 of a second conductivity, wherein the active region 101 is arranged between the first region 103and the second region 104.The layers of the semiconductor body 10 are stacked above each other along a stacking direction. The vertical directionY is oriented parallel to the stacking direction, and thelateral direction X refers to a direction orientedperpendicular to the vertical direction Y.- 19 –The first conductivity type is, for example, an n-type conductivity and the second conductivity type is, for example, a p-type conductivity or vice versa. For example, the first region 103 is doped with a first doping material and the second region 104 is doped with a second doping material.The active region 101 comprises a pn junction, a doubleheterostructure, a single quantum well (SQW), or a multiple quantum well (MQW) structure for generating or detecting electromagnetic radiation. The radiation is in particular emitted by the semiconductorbody 10 through the emission surface 10A. The emissionsurface 10A is preferably oriented parallel to a main planeof extension of the semiconductor body 10.A photosensitive material 20 is applied on the first side ofthe semiconductor body 10 to form a cavity 200 laterallysurrounding the emission surface 10A. The photosensitivematerial 20 is in particular a photoresist material. For example, the photosensitive material 20 is formed with an organic material such as a polymer or an epoxy. In particular, the photosensitive material 20 comprises thefollowing components: a resin that provides physicalproperties such as adhesion and / or chemical resistance, asensitizer which has a photoactive compound and a solventwhich keeps the resist liquid. The photosensitive material 20can be formed as a dry resist or a wet resist. Moreover, thephotosensitive material 20 can be formed as a positiveresist, wherein light will weaken the resist and create ahole in the illuminated regions, or as a negative resist,- 20 –wherein light will strengthen the resist and create an etchresistant mask in the illuminated regions.The cavity 200 is formed by the photosensitive material 20 onthe first side of the semiconductor body 10, on which theemission surface 10A is arranged. In particular, thephotosensitive material 20 laterally delimits the cavity 200.The photosensitive material 20 is shaped in the form of a damstructure surrounding the emission surface 10A.The cavity 200 is at least partially filled with a firstlayer 310 of wavelength converter material 30 comprisingconverter particles and a matrix material by using a screenprinting mask 40 defining a printing region 401. The cavity200 is in particular configured to delimit a lateralextension of the wavelength converter material 30.The wavelength converter material 30 is configured to atleast partially convert an electromagnetic radiation of afirst wavelength which is entering the converter material 30into electromagnetic radiation of a second wavelength. In particular, the second wavelength is greater than the firstwavelength. Preferably, the wavelength converter material 30emits electromagnetic radiation of the first and / or second wavelength. The wavelength converter material 30 is provided in the form of a slurry. The form of a slurry facilitates the application of the wavelength converter material 30 in a defined way. For example, the matrix material is a polysiloxane or an epoxywhich can be cured after being applied.- 21 –The screen printing mask 40 is for example formed with amesh. Partial areas of the screen printing mask 40 are madeimpermeable to the wavelength converter material 30, forexample by a blocking stencil, to define the printing region401. In particular, the printing region 401 is located inareas of the screen printing mask 40 which are not blocked bya blocking stencil and thus permeable to the wavelengthconverter material 30. A lateral extension of the printingregion 401 is equal to or smaller than a lateral extension ofthe emission surface 10A. Advantageously, this reduces theprecision required to position the printing region 401 of thescreen printing mask 40 relative to the cavity 200.Subsequently, a blade 402 or squeegee can be moved across thescreen printing mask 40 to fill the open mesh apertures withwavelength converter material 30, and a reverse stroke thencauses the screen printing mask 40 to touch the semiconductorbody 10 underneath the screen printing mask 40 momentarilyalong a line of contact. This causes the wavelength convertermaterial 30 to wet the semiconductor body 10 and be pulledout of the mesh apertures as the screen printing mask 40springs back after the blade 402 has passed. The use of the screen printing mask 40 enables a precise application of wavelength converter material 30 to the cavity 200 defined on the emission surface 10A of the semiconductorbody 10.Figure 1B shows a schematic cross-sectional view of a wafer 2 comprising a plurality of optoelectronic semiconductorcomponents 1 in a further step of a method for theirmanufacturing according to a first exemplary embodiment.- 22 –The cavities 200 are filled with the wavelength convertermaterial 30, and the screen printing mask 40 is removed.Figure 1C shows a schematic cross-sectional view of a wafer 2 comprising a plurality of optoelectronic semiconductorcomponents 1 in a further step of a method for theirmanufacturing according to a first exemplary embodiment. The step of applying wavelength converter material 30 is repeated and thus a second layer 320 of wavelength converter material 30 is applied to the first layer of 310 of wavelength converter material 30. The second layer 320 of wavelength converter material 30 is applied in a similar way as the first layer 310.Such a multilayered converter material 30 enables enhancedspectral characteristics and can lead to higher efficacy.Application and curing of several thin layers 310, 320 ofwavelength converter material 30 can advantageously reducethe formation of cracks. Preferably, the semiconductor body 10 is stored under a protective atmosphere between the steps of applying thedifferent layers 310, 320 of converter material 30. If keptin a protective atmosphere having reduced moisture, forexample, a color correction can be done after probing thesemiconductor body 10. The measured color point of emittedelectromagnetic radiation can be manipulated by applying dryphosphor, phosphor in solvent / light oil or phosphor insiloxane to the semiconductor body 10. Figure 1D shows a schematic cross-sectional view of a wafer 2 comprising a plurality of optoelectronic semiconductor- 23 –components 1 in a further step of a method for theirmanufacturing according to a first exemplary embodiment. The second layer 320 of the wavelength converter material 30 is applied to the side of the first layer 310 facing away from the semiconductor body 10. The screen printing mask 40is removed. The photosensitive material 20 protecting thebondpad regions 102 is freely accessible. Figure 1E shows a schematic cross-sectional view of a wafer 2 comprising a plurality of optoelectronic semiconductorcomponents 1 in a further step of a method for theirmanufacturing according to a first exemplary embodiment. The photosensitive material 20 protecting the bondpad regions102 is removed by a solvent, for example. The bondpad regions102 are freely accessible. Subsequently, the wafer 2 comprising a plurality of semiconductor components 1 is divided into a plurality of semiconductor components 1. In particular, the wafer 2 is singulated by sawing along the singulation lines T located between adjacent semiconductor components 1.Figures 2A to 2C show schematic cross-sectional views of anoptoelectronic semiconductor component 1 described herein according to different steps of a method for itsmanufacturing according to a second exemplary embodiment.The second exemplary embodiment is essentially equal to the first embodiment as shown in Figure 1C. In contrast to the first embodiment, the printing region 401 of the screen printing mask 40 extends over the entire surface of the wafer- 24 –2. Thus, the second layer 320 of wavelength convertermaterial 30 also extends over the entire surface of the wafer2 and also covers the bondpad regions 102. Figure 2B shows a further step of the method for manufacturing an optoelectronic semiconductor component 1,wherein the second layer 320 of the converter material 30 isat least partially removed by a grinding or sawing process. Thus, the photosensitive material 20 is freely accessible. Alternatively, the second layer 320 of the converter material 30 is at least partially removed by a laser cutting process. Figure 2C shows a further step of the method for manufacturing an optoelectronic semiconductor component 1, wherein the photosensitive material 20 is removed und the bondpad regions 102 are freely accessible.Figures 3A, 3B, 4A, 4B, 5A, 5B, 6A and 6B show schematic topviews and schematic cross-sectional views of anoptoelectronic semiconductor component 1 described herein according to different steps of a method for itsmanufacturing according to a third exemplary embodiment.Figure 3A shows a schematic top view of a wafer 2 comprisinga plurality of optoelectronic semiconductor components 1.Figure 3B in particular shows a detailed view of an optoelectronic semiconductor component 1 of the wafer 2according to Figure 3A. The optoelectronic semiconductorcomponent 1 comprises a semiconductor body 10 having anactive region 101 arranged between a first region 103 and a second region 104. Electromagnetic radiation generated in the- 25 –active region 101 is emitted through an emission surface 10A of the semiconductor body 10. Figure 4A shows a schematic top view of a wafer 2 comprisinga plurality of optoelectronic semiconductor components 1. Aphotosensitive material 20 is applied to a first main surface of the wafer 2. The photosensitive material 20 forms a plurality of cavities 200. Each cavity 200 is surrounding an emission surface 10A of an optoelectronic semiconductor component 1. Figure 4B in particular shows a detailed view of an optoelectronic semiconductor component 1 of the wafer 2according to Figure 4A. The photosensitive material 20 isarranged at the edges of the semiconductor body 10 andsurrounds the emission surface 10A. In particular, thephotosensitive material 20 has an aspect ratio of 1:1. The aspect ratio defines a ratio between an extension in the vertical direction Y relative to the extension in the lateral direction X. Preferably, the photosensitive material 20 has avertical extension of at least 45 µm.Figure 5A shows a schematic top view of a wafer 2 comprisinga plurality of optoelectronic semiconductor components 1. Ascreen printing mask 40 is arranged above the wafer 2. The screen printing mask 40 may extend over the entire wafer in the lateral directions. However, to have a better visibilityof the wafer 2 underneath the screen printing mask 40, thescreen printing mask 40 is drawn slightly smaller. Figure 5B in particular shows a detailed view of an optoelectronic semiconductor component 1 of the wafer 2according to Figure 5A. The screen printing mask 40 has a- 26 –defined printing region 401 in which it is permeable towavelength converter material 30.Subsequently, a blade 402 or squeegee can be moved across thescreen printing mask 40 to fill the open mesh apertures withwavelength converter material 30, and a reverse stroke thencauses the screen printing mask 40 to touch the semiconductorbody 10 underneath the screen printing mask 40 momentarilyalong a line of contact. This causes the wavelength convertermaterial 30 to wet the semiconductor body 10 and be pulledout of the mesh apertures as the screen printing mask 40 springs back after the blade 402 has passed. The use of the screen printing mask 40 enables a precise application of wavelength converter material 30 to the cavity 200 defined on the emission surface 10A of the semiconductor body 10. Figure 6A shows a schematic top view of a wafer 2 comprisinga plurality of optoelectronic semiconductor components 1. Thewavelength converter material 30 is filled into the cavities200 of all semiconductor components 1 of the wafer 2. Figure 6B in particular shows a detailed view of an optoelectronic semiconductor component 1 of the wafer 2according to Figure 6A. The wavelength converter material 30is distributed evenly in the cavity 200, and the screenprinting mask 40 is removed. For example, the wavelengthconverter material 30 is subsequently cured. Additionally,the photosensitive material 20 can be removed after thewavelength converter material 30 is applied.- 27 –Figures 7A to 7G show schematic cross-sectional views of anoptoelectronic semiconductor component 1 described herein according to different steps of a method for itsmanufacturing according to a fourth exemplary embodiment.The steps shown in Figures 7A to 7D are essentially equal to the steps as described in Figures 3A,B to 6A,B. In contrast, the semiconductor body 10 comprises a bondpad region 102. Thebondpad region 102 in particular comprises a metal elementconfigured to inject charge carriers into the semiconductorbody 10.Figure 7B shows a further step of the method according to which the photosensitive material 20 is arranged such that the bondpad region 102 is laterally surrounded by the photosensitive material 20. The bondpad region 102 is locatedadjacent to the cavity 200 and is thus not filled with theconverter material.The use of a screen printing mask 40 in combination with aphotosensitive material 20 can advantageously restrict the application of wavelength converter material 30 to the cavity200 above the emission surface 10A and spare other parts ofthe chip surface in which for example the bondpad region 102is arranged. Thus, the bondpad region 102 remains accessiblefor probing. Figure 7C shows a further step of the method according towhich a wavelength converter material 30 is applied to thesemiconductor body 10 using a screen printing mask 40. Figure 7D shows a further step of the method according towhich a probing using a probing needle 50 to electrically- 28 –connect the semiconductor body 10 is performed. This enablesthe measurement of optical emission characteristics such as acolor point of an electromagnetic radiation emitted by thesemiconductor body 10.In particular, the spectral emission characteristics of the semiconductor component 10 are measured after applying the first layer 310 and / or the second layer 320 of convertermaterial 30.Figure 7E shows a further step of the method according towhich a repeated step of applying a second layer 320 ofwavelength converter material 30 is performed. By theadditional application of wavelength converter material 30,the color point of emitted radiation can be further adjusted.Figure 7F shows a further step of the method according to which the probing needle 50 is electrically connected to the bondpad region 102 to inject charge carriers into the semiconductor body 10. Figure 7G shows a further step of the method according towhich the wavelength converter material 30 is partiallyremoved by using a grinding device 60. A removal by polishing or grinding can precisely adjust the color point of emittedelectromagnetic radiation. Furthermore, a protection layer 70is arranged on the bondpad region 102 to protect the bondpad from any damages. The protection layer 70 is in particular formed with one of the following materials: water-soluble resist, photo resist, grease, thin metal.Figures 8A to 8D show schematic cross-sectional views of anoptoelectronic semiconductor component 1 described herein- 29 –according to different steps of a method for itsmanufacturing according to a fifth exemplary embodiment.Figure 8A shows a step of the method in which a first layer310 of a wavelength converter material 30 is applied to acavity 200 on a semiconductor body 10. The screen printing mask 40 has a printing region 401 which is smaller than the lateral extension 200X of the cavity 200. In particular, side surfaces of the cavity 200 are at a distance D to theprinting region 401 of at least 5 µm, preferably of at least10 µm and particularly preferably of at least 15 µm. In otherwords, a lateral extension of the printing region 401 is atleast 10 µm smaller, preferably at least 20 µm andparticularly preferably at least 30 µm smaller than thelateral extension 200X of the cavity 200. Figure 8B shows a further step of the method according towhich the wavelength converter material 30 is only applied toa central area of the cavity 200. In other words, afterapplication the wavelength converter material 30 is arrangedat a distance D from the photosensitive material 20. Figure 8C shows a further step of the method after a centrifugal process was performed. The centrifugal processlaterally distributes the wavelength converter material 30evenly in the cavity. In particular, a direction of a centripetal acceleration is oriented parallel to a normalvector of the optoelectronic semiconductor component 1. Inother words, the centrifugal process is configured in such a way that a centripetal acceleration is aligned in the vertical direction Y.- 30 –As can be seen from the gradual change in shading inside thewavelength converter material 30, the centrifugal processcaused a sedimentation. Depending on a duration of thecentrifugal process and the amount of centripetal acceleration, the converter particles and the matrix materialof the wavelength converter material 30 will separate fromeach other. In particular, the centrifugal process causes asedimentation of wavelength converter particles towards theemission surface 10A of the semiconductor body 10, becausethe converter particles have a higher specific weight than the matrix material. In particular, the screen printing mask 40 can remain attached to the semiconductor component 1 while the centrifugal process is performed. Thus, the screen printing mask 40 can be cleaned from residues of the wavelengthconverter material simultaneously.Subsequently, the matrix material concentrated on a side ofthe wavelength converter material 30 facing away from thesemiconductor body 10 can be at least partially removed. Forexample, the matrix material is removed by a solvent orplasma matrix material removal. The removal of matrixmaterial can avoid any negative influences of the matrix materials such as a subsequent formation of cracks in theconverter material, for example. By removal of the matrixmaterial, the filling degree is increased to at least 90 wt%,preferably to at least 95 wt%. Figure 8D shows a further step of the method according towhich a second layer 320 of wavelength converter material 30is applied to the first layer 310 of wavelength convertermaterial 30. The first layer 310 can either be cured before- 31 –the second layer 320 is applied or be applied directly to the wet material of the first layer 310. 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. This patent application claims the priority of the German patent application 102024109595.4, the disclosure content of which is hereby incorporated by reference.

[0002] - 32 –References1 optoelectronic semiconductor component2 wafer10 semiconductor body101 active region102 bondpad region103 first region104 second region20 photosensitive material200 cavity30 wavelength converter material310 first layer of converter material320 second layer of converter material40 screen printing mask401 printing region402 blade50 probing needle60 grinding device70 protection layer10A emission surface200X lateral extension of the cavityT singulation linesX lateral directionY vertical direction

Claims

- 33 –Claims1. Method for manufacturing an optoelectronic semiconductorcomponent (1), comprising the steps of:- providing a semiconductor body (10) having an active region(101) configured to emit an electromagnetic radiation through an emission surface (10A) on a first side of thesemiconductor body (10),- applying a photosensitive material (20) on the first sideof the semiconductor body (10) to form a cavity (200)laterally surrounding the emission surface (10A),- at least partially filling the cavity (200) with awavelength converter material (30) comprising converterparticles and a matrix material by using a screen printingmask (40) defining a printing region (401).

2. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to the preceding claim, wherein- the semiconductor body (10) comprises a bondpad region(102) which is located adjacent to the cavity (200) and isthus not filled with the converter material (30).

3. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- a lateral extension of the printing region (401) is smallerthan a lateral extension of the cavity (200X).

4. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- a centrifugal process laterally distributes the wavelengthconverter material (30) evenly in the cavity (200).- 34 –5. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to the preceding claim, wherein- the centrifugal process causes a sedimentation in thewavelength converter material (30).

6. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- the matrix material is partially removed from thewavelength converter material (30) by a solvent or plasmamatrix material removal.

7. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- a lateral extension of the printing region (401) is equalto a lateral extension of the semiconductor component (1) andextends beyond the bondpad region (102).

8. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- the step of applying the converter material (30) isrepeated and a second layer (320) of converter material (30)is subsequently deposited on top of a first layer (310) ofconverter material (30).

9. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to the preceding claim, wherein- the semiconductor body (10) is stored under a controlledatmosphere between the steps of applying the different layersof converter material (30) without curing.- 35 –10. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- spectral emission characteristics of the semiconductorcomponent (1) are measured after applying the convertermaterial (30) by contacting the bondpad region (102) with aprobing needle (50).

11. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- the converter material (30) is partially removed by usingone of the following methods: polishing, grinding.

12. Method for manufacturing an optoelectronic semiconductorcomponent (1) according to one of the preceding claims, wherein- a forced-siloxane crack-in is performed on the convertermaterial (30) by exposing the converter material to UVCradiation.

13. Method for manufacturing a plurality of optoelectronicsemiconductor components (1) according to one of thepreceding claims, wherein- the method steps of the preceding claims are carried out ona wafer level and the semiconductor components (1) aresubsequently singulated.

14. Method for manufacturing a plurality of optoelectronicsemiconductor components (1) according to the precedingclaim, wherein- 36 –- the bondpad regions (102) are exposed before thesemiconductor components (1) are singulated.

15. Method for manufacturing a plurality of optoelectronicsemiconductor components (1) according to one of the preceding claims, wherein- the semiconductor components (1) are singulated using asawing process.

16. Method for manufacturing a plurality of optoelectronicsemiconductor components (1) according to one of the preceding claims, wherein- the semiconductor components (1) are singulated using astealth dicing process.

17. Method for manufacturing a plurality of optoelectronicsemiconductor components (1) according to one of the preceding claims, wherein- the semiconductor components (1) are singulated using alaser ablation process.

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