Method of producing an optoelectronic component and optoelectronic component

Abstract

A method of producing an optoelectronic component (1) comprises the following method steps. A wavelength distribution map (13) is generated comprising a spatially resolved distribution of wavelengths emitted at an emission face (9) of a converter material (8) arranged at an optoelectronic semiconductor chip (5). A thickness map (14) is generated based on the wavelength distribution map (13) comprising local changes of a converter material thickness dependent on variations of the wavelengths of the wavelength distribution map (13) with respect to a targeted colorimetric locus. At least a part of the converter material (8) is removed at its emission face (9) based on the thickness map (14).

Description

[0001] METHOD OF PRODUCING AN OPTOELECTRONIC COMPONENT AND OPTOELECTRONIC COMPONENT

[0002] DESCRIPTION

[0003] The present invention refers to a method of producing an optoelectronic component and an optoelectronic component .

[0004] This patent application claims the priority of German patent application 10 2023 135 608 . 9 , the disclosure content of which is hereby incorporated by reference .

[0005] Optoelectronic components such as light emitting diodes ( LEDs ) which are designed to emit electromagnetic radiation from speci fic wavelength ranges are known from the state of the art . Colour conversion of electromagnetic radiation is required in particular to achieve an emission of white light . Typically, blue light emitting optoelectronic semiconductor chips are j oint with a converter material which also can be called a phosphor . To achieve a certain colour point , a wavelength of electromagnetic radiation emitted by the optoelectronic semiconductor chip and a degree of conversion which is for example dependent on a convertor material amount need to match .

[0006] Today, for colour steering, conversion is done by attaching a conversion element on each optoelectronic semiconductor chip individually, after a die attach on a substrate . As both, the optoelectronic semiconductor chip and the conversion element are characterised before the attachment processes , a good colour match is possible . The costs for this approach are rather high and it bears additional reliability risks , both especially arising from the additional conversion element attachment process .

[0007] Wafer-level conversion is signi ficantly cheaper and can provide further benefits , while there is no local colour steering available yet . Current wafer-level conversion approaches comprise a grinding step which is globally applied on the whole wafer area and cannot yield a locally adj usted conversion level .

[0008] An obj ective of the present invention is to speci fy an improved method of producing an optoelectronic component and to provide an improved optoelectronic component . This obj ective is solved by a method of producing an optoelectronic component and an optoelectronic component according to the independent claims . Advantageous embodiments are speci fied in the dependent claims .

[0009] A method of producing an optoelectronic component comprises the following method steps . An optoelectronic arrangement arranged on a top side of carrier is provided comprising an optoelectronic semiconductor chip arranged at the top side of the carrier and a converter material arranged at the optoelectronic semiconductor chip . The optoelectronic semiconductor chip is designed to emit electromagnetic radiation from a first wavelength range at a first emission face . The converter material is arranged at the first emission face of the optoelectronic semiconductor chip and is designed to absorb electromagnetic radiation emitted by the optoelectronic semiconductor chip and to emit electromagnetic radiation from a second wavelength range at a second emission face . The optoelectronic arrangement is designed to emit electromagnetic radiation comprising a combined wavelength range composed of electromagnetic radiation from the first wavelength range and the second wavelength range . A wavelength distribution map of the optoelectronic arrangement is generated . The wavelength distribution map of the optoelectronic arrangement comprises a spatially resolved distribution of wavelengths of electromagnetic radiation emitted at the second emission face of the converter material . A thickness map is generated based on the wavelength distribution map . The thickness map comprises information about local changes of a converter material thickness with respect to the first emission face of the optoelectronic semiconductor chip dependent on variations of the wavelengths of the wavelength distribution map and with respect to a targeted colorimetric locus of the combined wavelength range . At least a part of the converter material is removed at the second emission face based on the thickness map .

[0010] The optoelectronic semiconductor chip comprises a sequence of thin films including especially semiconductor thin films . Due to the nature of a deposition technique , equipment and parameters used during a deposition of the thin films the optoelectronic semiconductor chip comprises a certain local varia- tion / inhomogeneity of the emission wavelength spectrum at the first emission face . E . g . , the thin films of the optoelectronic semiconductor chips can be deposited at least partially by epitaxy . An epitaxial deposition is characteri zed in that a structure of a material to be deposited is given by a structure of an underlying surface and that at least one crystallographic direction of the deposited material corresponds to a crystallographic direction of the underlying surface . A wavelength inhomogeneity can occur due to a non- uni form epitaxy process , e . g . due to locally fluctuating conditions .

[0011] A conversion ef ficiency of the conversion material is dependent on its thickness as the conversion depends on an absorption process followed by relaxation and reemission, wherein reemitted electromagnetic radiation can be absorbed again . As the converter material is removed locally based on the thickness map a local change of a degree of wavelength conversion is achieved which allows to adj ust and correct a spatial variation of the wavelength according to the wavelength distribution map in order to obtain an emission of light from the targeted colorimetric locus in sum . The targeted colorimetric locus can be represented as a point or an area in colour space and describes the colour of the combined wavelength spectrum of the optoelectronic arrangement . Here , a thickness reduction of the conversion layer can be carried out globally but especially locally . Based on the wavelength distribution map the degree of convertor material removal is locally matched with inhomogeneities of the emission spectrum of the first emission face of the optoelectronic semiconductor chip to obtain the targeted colour across the whole second emission face of the converter . As a result , the conversion is locally tuned by the thickness of the conversion material . Advantageously, the optoelectronic component thus comprises a smaller colour distribution and the colour yield is increased . Also , the optoelectronic component comprises a better colour over angle and in total superior colour steering .

[0012] In an embodiment removing of the converter material at the second emission face is performed by milling . In this case the thickness map can also be called a milling map . Compared to current global grinding approaches , besides the local colour steering, there is an additional advantage of less contaminations on the second emission face of the conversion material in contrast to grinding the second emission face as a mill does not comprise grinding particles fixed by an organic matrix which can cause residues of debris on the second emission face i f they become loose .

[0013] In an embodiment milling is performed by scanning a milling head across the second emission face . The local conversion degree - via convertor layer thickness - is tuned by milling of f excessive material using guided surface scanning, e . g . , CNC-guided scanning . With a CNC-based milling approach, the surface can be scanned based on the wavelength distribution map and hence the amount of converter material removal can be tuned accordingly . A dimension / diameter of the milling head can be chosen based on a required lateral resolution of the thickness map . Alternatively, the local milling can be applied after a global thinning step for a local correction step only . Advantageously, a high vertical precision can be achieved since the milling head does not wear much in the vertical dimension but more lateral in contrast to a grinding disc or similar .

[0014] In an embodiment the wavelength distribution map is generated by measuring photoluminescence intensities for di f ferent wavelengths at the second emission face spatially resolved and mapping a peak wavelength for di f ferent areas of the second emission face . Advantageously, such a photoluminescent setup allows to measure variations of the wavelength very precisely . Alternatively, a mean or a median wavelength may be mapped for di f ferent areas of the second emission face instead of a peak wavelength . A peak wavelength is the wavelength of electromagnetic radiation emitted in a certain area of the second emission face which comprises the maximum intensity .

[0015] In an embodiment the optoelectronic arrangement comprises a plurality of optoelectronic semiconductor chips arranged at the top side of the carrier each having a first emission face . Providing the optoelectronic arrangement comprises a step of arranging the converter material at the first emission faces of the optoelectronic semiconductor chips simultaneously . A separate wavelength distribution map and a separate thickness map, each thickness map being based on a wavelength distribution map, are generated for each combination of an optoelectronic semiconductor chip and the converter material and the removing of at least a part of the converter material at second emission faces of the converter material is performed based on the respective thickness maps . Advantageously, the colorimetric loci for each combination of optoelectronic semiconductor chip and converter material can be within a MacAdam ellipse , e . g . within a 5-step MacAdam ellipse , preferably a 3-step, ideally a 1-step MacAdam ellipse .

[0016] In this embodiment the carrier can also be called a wafer . This variant of the method represents an approach for local colour correction on a wafer level since the converter material is arranged in one method step for all optoelectronic semiconductor chips . When applying the convertor material on a wafer level , it is not possible to adj ust the conversion ef ficiency . Once the conversion layer is applied onto the chip wafer, its thickness is in quite uni form . Hence , a certain distribution of the colour is obtained instead of the targeted colour point for each optoelectronic semiconductor chip, resulting in a lower colour yield . Advantageously, a better colour steering for a plurality of optoelectronic semiconductor chips results in lower production and product costs . The converter material can for example be arranged by means of a dosing method . In another embodiment the converter material is not arranged simultaneously on the first emission faces of the optoelectronic semiconductor chips but successively . In this case , also a wafer-level approach is reali zed as the converter material can be arranged successively but in the same manner independent of the actual optoelectronic semiconductor chip and without having the conversion ef ficiency adj usted to each optoelectronic semiconductor chip .

[0017] In an embodiment providing the optoelectronic arrangement comprises the following steps : The optoelectronic semiconductor chip is arranged at the top side of the carrier . The optoelectronic semiconductor chip is embedded into a resist . The resist is structured such that a cavity is formed at the first emission face of the optoelectronic semiconductor chip and the first emission face is uncovered by the resist . The converter material is arranged in the cavity and at the first emission face of the optoelectronic semiconductor chip . In another embodiment a plurality of optoelectronic semiconductor chips is arranged at the top side of the carrier and embedded into the resist . The resist is structured such that cavities are formed at the first emission faces of the optoelectronic semiconductor chips and the first emission faces are uncovered by the resist . The converter material is arranged in the cavities and at the first emission faces of the optoelectronic semiconductor chips . Arranging of optoelectronic semiconductor chips can e . g . be performed by epitaxy . In another embodiment the resist can be used to protect elec- trical contacts of the optoelectronic semiconductor chip . In this case , the cavity is omitted and the resist is structured such it covers the electrical contacts while the first emission face remains uncovered by the resist in order to arrange the converter material at the emission face .

[0018] In an embodiment the method comprising the following additional steps . Converter material parts arranged above the cavity with respect to the top side of the carrier are grinded to uncover the resist . This step may be omitted i f the resist was uncovered by the converter material initially . The uncovered resist is removed from the carrier . This grinding step to uncover the resist may be a first grinding step within the production of the optoelectronic component . Removing the resist may expose electrical contact pads arranged at the top side of the carrier in order to electrically contact the optoelectronic semiconductor chips .

[0019] In an embodiment the method grinding the converter material globally at the second emission face is performed prior to removing the converter material at least partially at the second emission face based on the thickness map locally . In this case a second grinding step is performed, wherein the converter material is thinned globally first to hit a certain colour target range and to get rid of excessive converter material very quick . The second grinding step can be performed after the first grinding step and removing the resist from the carrier .

[0020] In an embodiment the converter material comprises at least one phosphor embedded into a matrix material or a ceramic phosphor . Ceramic converters allow high temperatures into the system . Ceramic converters are consequently essential when it comes to high power optoelectronic semiconductor chips . A phosphor embedded into a matrix comprises the advantage that typically a soft matrix material is used . The soft matrix material can easily be grinded and milled . In an embodiment the matrix material comprises polysiloxane . The matrix material may can also comprise another material , especially polymers and other plastics .

[0021] In an embodiment the thickness of the converter is reduced by up to 1pm during the removing of at least a part of the converter material at the second emission face based on the thickness map . However, the range within the thickness of the converter material is reduced may also be equal or larger than 1pm . The exact amount of converter material which needs to be removed locally e . g . , depends on the phosphor material which is used and its concentration within the matrix material . Typically, the thickness of the converter material will be reduced by an amount in the range of several hundreds nanometres to several micrometres .

[0022] An optoelectronic component comprises a carrier with a top side , an optoelectronic semiconductor chip arranged at the top side of the carrier and a converter material arranged at the optoelectronic semiconductor chip . The optoelectronic semiconductor chip is designed to emit electromagnetic radiation from a first wavelength range at a first emission face . The converter material is arranged at the first emission face of the optoelectronic semiconductor chip and is designed to absorb electromagnetic radiation emitted by the optoelectronic semiconductor chip and to emit electromagnetic radiation from a second wavelength range at a second emission face . The optoelectronic arrangement is designed to emit electromagnetic radiation comprising a combined wavelength range composed of electromagnetic radiation from the first wavelength range and the second wavelength range . The converter material comprises a thickness with respect to first emission face of the optoelectronic semiconductor chip which is modulated across the second emission face such that relative wavelength variations of electromagnetic radiation emitted in di f ferent areas of the first emission face are compensated by the converter material locally . The above-described properties , features and advantages of this invention and the way in which they are achieved will become clearer and more clearly understood in association with the following description of the exemplary embodiments which are explained in greater detail in association with the drawings . Here in schematic illustration in each case :

[0023] Fig . 1 : elements of an optoelectronic component in a side view;

[0024] Fig . 2 : an exemplary spectrum illustrating the principle of colour conversion with phosphors ;

[0025] Fig . 3 : an exemplary wavelength distribution map of the optoelectronic component before completing its production;

[0026] Fig . 4 : an exemplary thickness map generated based on the wavelength distribution map ;

[0027] Fig . 5 : a method step of a method of producing the optoelectronic component based on the thickness map ; and

[0028] Fig . 6 : further method steps of the method of producing the optoelectronic component .

[0029] Fig . 1 schematically shows elements of an optoelectronic component 1 in a side view . The optoelectronic component 1 can e . g . , be part of a lamp, for example a headlamp, or part of a display or any other optoelectronic device .

[0030] The optoelectronic component 1 comprises a carrier 2 . The carrier 2 comprises a top side 3 and a bottom side 4 opposite the top side 3 . The carrier 2 comprises silicon but the carrier 2 can alternatively or additionally comprise other materials , for example another carrier material , a dopant or additional layers . The optoelectronic component 1 comprises an optoelectronic semiconductor chip 5 arranged at the top side 3 of the carrier 2 . The optoelectronic semiconductor chip 5 comprises a first emission face 6 and a mount face 7 opposite the first emission face 6 . The optoelectronic semiconductor chip 5 is arranged with its mount face 7 at the top side 3 of the carrier 2 , while the first emission face 6 is facing away from the top side 3 of the carrier 2 .

[0031] The optoelectronic semiconductor chip 5 is designed to emit electromagnetic radiation at its first emission face 6 . The optoelectronic semiconductor chip 5 is exemplary designed as a light emitting diode ( LED) . However, the optoelectronic semiconductor chip 5 can alternatively be designed as a laser diode . The optoelectronic semiconductor chip 5 comprises a sequence of layers including semiconductor thin films which are arranged parallel to the top side 3 of the carrier 2 . The layers / thin films can be deposited by means of epitaxy . However, other deposition methods can also be used which are not based on an epitaxial relationship between a material to be deposited on an underlying surface .

[0032] The optoelectronic semiconductor chip 5 comprises an active region within which electromagnetic radiation is generated by recombination of charge carriers . The optoelectronic semiconductor chip 5 is designed to emit the generated electromagnetic radiation at the first emission face 6 . The optoelectronic semiconductor chip 5 can additionally be designed to emit electromagnetic radiation at its side faces extending between the mount face 7 and the first emission face 6 . The optoelectronic semiconductor chip 5 is designed to emit electromagnetic radiation from a first wavelength range . The first wavelength range depends on the materials used for the optoelectronic semiconductor chip 5 and its layers / thin films . As an example , the optoelectronic semiconductor chip 5 comprises InGaN and is designed to emit electromagnetic radiation from a wavelength range which corresponds to blue light . The deposition technique and parameters during the deposition also influence the wavelength rang of emitted electromagnetic radiation . A converter material 8 is arranged at the first emission face 6 of the optoelectronic semiconductor chip 5 . The converter material 8 is designed to absorb electromagnetic radiation emitted by the optoelectronic semiconductor chip 5 and to emit electromagnetic radiation from a second wavelength range at a second emission face 9 . The second emission face 9 is arranged opposite the first emission face 6 of the optoelectronic semiconductor chip 5 and facing away from it and the top side 3 of the carrier 2 . In other words , the optoelectronic semiconductor chip 5 I arranged between the carrier 2 and the converter material 8 with respect to a direction perpendicular to the top side 3 of the carrier 2 . The optoelectronic semiconductor chip 5 and the converter material 8 form an optoelectronic arrangement 10 arranged on the top side 3 of the carrier 2 .

[0033] The converter material 8 comprises at least one phosphor embedded into a matrix material . Exemplarily, the matrix material comprises polysiloxane or silicone . However, the matrix material can also comprise another material e . g . , a polymer or another plastic . The converter material 8 can comprise a plurality of layers comprising di f ferent matrix materials , wherein some of the layers may comprise similar matrix materials . At least one phosphor is embedded into each layer of matrix materials , wherein di f ferent layers can comprise di fferent phosphor materials . Alternatively, the converter material 8 can comprise at least one ceramic phosphor .

[0034] Fig . 2 schematically shows an exemplary spectrum which illustrates the principle of colour conversion by the conversion material 8 . The spectrum shows intensities plotted against the wavelength .

[0035] Fig . 2 shows a first spectrum 11 of the optoelectronic semiconductor chip 5 which represents electromagnetic radiation emitted from the first wavelength range at the first emission face 6 . Fig . 2 also shows a second spectrum 12 which repre- sents electromagnetic radiation emitted by the conversion material 8 from the second wavelength range , which is an emission spectrum of the phosphor embedded into the converter material 8 . The second spectrum 12 mostly comprises higher wavelengths than the first spectrum 11 because a relaxation of electrons in deeper energetic states occurs in the phosphor after absorbing electromagnetic radiation emitted by the optoelectronic semiconductor chip 5 from the first wavelength range .

[0036] At the second emission face 9 , the optoelectronic arrangement 10 is designed to emit electromagnetic radiation comprising a combined wavelength range composed of electromagnetic radiation from the first wavelength range and the second wavelength range . In other words , the optoelectronic arrangement 10 is designed to emit electromagnetic radiation with a total spectrum corresponding to a sum of the first spectrum 11 and the second spectrum 12 because electromagnetic radiation from the first spectrum 11 not only is absorbed by the phosphor but also can pass though the converter material 8 unconverted .

[0037] Fig . 2 shows the exemplary case where the first spectrum 11 corresponds to the spectrum of a blue light emitting diode , whereas the second spectrum 12 corresponds to the emission spectrum of a converter material 8 that comprises a yellow phosphor designed to achieve an emission of white light in sum at the second emission face 9 . An optoelectronic semiconductor chip 5 which is designed to emit blue light can for example comprise InGaN . In order to generate yellow light using blue incident light , the converter material 8 can for example comprise a Ce3+based phosphor .

[0038] In another embodiment the optoelectronic semiconductor chip 5 is designed to emit blue light whereas the converter material 8 comprises two phosphors which are designed to generate green and red light in order to emit white light in sum at the second emission face 6 . In another embodiment the optoe- lectronic semiconductor chip 5 is designed to emit UV-light whereas the converter material 8 comprises three phosphors which are designed to generate red, green and blue light in order to emit white light in sum at the second emission face 6 . In both cases , the converter material 8 can e . g . , comprise a Eu2+based or a Eu3+based phosphor . Di f ferent phosphor types are known and available for di f ferent spectral ranges . E . g . , CaSi2N2O2 : Eu can be used for a conversion with an emission maximum at 565nm while SrSiN2 : Eu can be used for a conversion with an emission maximum at 700nm .

[0039] A conversion ef ficiency is dependent on an amount of converter material 8 and a density of the at least one phosphor embedded into the matrix material . One ef fect that occurs for such optoelectronic arrangements 10 is that the wavelength of electromagnetic radiation emitted at the first emission face 6 of the optoelectronic semiconductor chip 5 can vary dependent on a location on the first emission face 6 due to inhomogeneities during the deposition process of the layers / thin films of the optoelectronic semiconductor chip 5 which can be caused by defects , impurities and / or fluctuating parameters across the top side 3 of the carrier 2 during the deposition . In other words , electromagnetic radiation emitted in di f ferent areas of the first emission face 6 can comprise di f ferent wavelengths which can be below or above a certain wavelength target .

[0040] After arranging the converter material 8 at the first emission face 6 of the optoelectronic semiconductor chip 5 , the converter material 8 comprises a rather homogenous thickness measured perpendicular to the top side 3 of the carrier 2 . Consequently, inhomogeneities with respect to the wavelength of electromagnetic radiation emitted at the first emission face 6 also occur for electromagnetic radiation emitted at the second emission face 9 .

[0041] Fig . 3 schematically shows an exemplary wavelength distribution map 13 across the second emission face 9 of the optoe- lectronic component 1 of Fig . 1 . Exemplarily, the second emission face 9 comprises a circular shape which is why the wavelength distribution map 13 also comprises a circular shape . Fig . 3 shows a distribution of wavelengths in a top view onto the optoelectronic component 1 and the second emission face 9 . The second emission face 9 can also comprise other geometric shapes .

[0042] The wavelength distribution map 13 of the optoelectronic arrangement 10 comprises a spatially resolved distribution of wavelengths of electromagnetic radiation emitted at the second emission face 9 of the converter material 8 . In the exemplary embodiment the wavelength distribution map 13 comprises wavelengths which comprise a blue shi ft and a red shi ft compared to a targeted colorimetric locus of electromagnetic radiation emitted at the second emission face 9 of the optoelectronic arrangement 10 . Note , that in Fig . 3 both, red shi fts and blue shi fts are represented with a grey scale . E . g . , at red shi fts and blue shi fts are present both at an edge of the second emission face 9 which both occur as dark regions in the wavelength distribution map 13 .

[0043] The wavelength distribution map 13 can be generated by measuring photoluminescence intensities for di f ferent wavelengths at the second emission face 9 spatially resolved and mapping a peak wavelength for di f ferent areas of the second emission face 9 . Alternatively, mean or median or other values of the wavelength can be mapped . In other words , the wavelength distribution map 13 comprises a partition of the second emission face 9 into pixels and a peak wavelength or some other suitable wavelength value for every pixel of the second emission face 9 , independent of the exact method the wavelength value has been acquired .

[0044] As can be seen in Fig . 3 , inhomogeneities with respect to the wavelength of electromagnetic radiation emitted at the first emission face 6 also occur at the second emission face 9 . Exemplarily, the wavelength distribution map 13 comprises a range of peak wavelengths ranging from 434nm to 453 , 5nm with a mean value of the peak wavelengths of the pixels of 443 , 8nm and a standard deviation of 0 , 732 % which corresponds to 3 , 25nm .

[0045] In the following, a method for producing the optoelectronic component 1 is described which allows to compensate the inhomogeneities of the wavelength distribution across the second emission face 9 . After providing the optoelectronic arrangement 10 the wavelength distribution map 13 of the optoelectronic arrangement 10 is generated . Afterwards , a thickness map 14 is generated based on the wavelength distribution map 13 . Fig . 4 schematically shows the generation of the thickness map 14 based on the wavelength distribution map 13 . The thickness map 14 comprises local changes of a converter material thickness measured with respect to the top side 3 of the carrier 2 which is dependent on the variations of the wavelengths of the wavelength distribution map 13 , e . g . of the peak wavelengths , with respect to a targeted colorimetric locus of the combined wavelength range of the optoelectronic arrangement . A thickness change of the thickness of the converter material 8 can e . g . , be some function of a wavelength variation . Fig . 4 shows an exemplary thickness map 9 which is based on the wavelength distribution map 13 of Fig . 3 .

[0046] Fig . 5 schematically shows a further method step of removing at least a part of the converter material 8 at the second emission face 9 based on the thickness map 14 .

[0047] Removing of the converter material 8 at the second emission face 9 can be performed by milling as illustrated in Fig . 5 exemplarily . The milling can be performed by scanning a milling head 15 across the second emission face . The thickness of the converter material 8 can be reduced by up to 1pm, for example . As a result , the converter material 8 comprises a thickness which is modulated across the second emission face 9 such that wavelength variations of electromagnetic radiation emitted in di f ferent areas of the first emission face 6 are compensated by the converter material 8 locally . In Fig . 5 , this is illustrated by a homogenous further wavelength distribution map 16 comprising a homogenous wavelength distribution of e . g . , peak wavelengths , while the thickness of the converter material 8 is modulated according to the thickness map 14 .

[0048] Fig . 6 schematically shows optional further method steps of the method of producing an optoelectronic component 1 prior to the removal of at least a part of the converting material 8 at the second emission face 9 i . e . , the optional method steps of Fig . 6 can be performed before the method step shown in Fig . 5 .

[0049] Fig . 6 exemplarily shows the case where the optoelectronic arrangement 10 of the produced optoelectronic component 1 comprises a plurality of optoelectronic semiconductor chips 5 arranged at the top side 3 of the carrier 3 each having a first emission face 6 facing away from the top side 3 of the carrier 2 . Exemplarily, two optoelectronic semiconductor chips 5 are provided .

[0050] Providing the optoelectronic arrangement 10 can comprises a step of arranging the converter material 8 at the first emission faces 6 of the optoelectronic semiconductor chips 5 simultaneously . In this case , a separate wavelength distribution 13 map and a separate thickness map 14 are generated for each combination of an optoelectronic semiconductor chip 5 and the converter material 8 . The removing of at least a part of the converter material 8 at second emission faces 9 of the converter material 8 is performed based on the respective thickness maps 14 .

[0051] In this case , a wafer-level approach is reali zed as the converter material 8 is arranged simultaneously at the first emission faces 6 . Even i f the converter material 8 is arranged successively, a wafer level approach is reali zed since the arrangement of the converter material 8 is performed in- dependent of underlying wavelength distribution maps 13 . Thus , the converter material 8 initially comprises a homogenous thickness above all optoelectronic semiconductor chips 5 . However, the converter material 8 is removed at least partially at each second emission face 9 of the optoelectronic arrangement 10 based on the thickness maps 14 . Thus , an optoelectronic component 1 can be provided with improved colour steering for all optoelectronic semiconductor chips 5 and second emission faces 9 .

[0052] The following description of the method steps of Fig . 6 also applies to the production of an optoelectronic component 1 comprising an optoelectronic arrangement 10 with only one optoelectronic semiconductor chip 5 .

[0053] According to Fig . 6 , providing the optoelectronic arrangement 10 comprises the following steps . The optoelectronic semiconductor chips 5 are arranged at the top side 3 of the carrier 2 . Afterwards , the optoelectronic semiconductor chips 5 are embedded into a resist 17 . The resist 17 is structured such that cavities 18 are formed at the first emission face 6 of the optoelectronic semiconductor chips 5 , wherein the first emission faces are uncovered by the resist 17 . In other words , the first emission faces 6 form bottoms of the cavities 18 . A state after structuring the resist 17 is shown on the very top of Fig . 6 . The resist 17 can be designed as a photoresist .

[0054] In a further method step the converter material 8 is arranged in the cavities 18 and at the first emission faces 6 of the optoelectronic semiconductor chips 5 . The converter material 8 is also beyond the cavities 18 such that the converter material 8 covers the structured resist 17 completely .

[0055] In a further method step the excessive converter material 8 arranged above the cavities 18 with respect to the top side 3 of the carrier 2 is grinded to uncover the resist 17 . This step may be called a first grinding step . In contrast to milling, grinding is performed globally . In a further method step the uncovered resist 17 is removed from the carrier 3 . Thus , electrical contact pads 19 which arranged at the top side 3 of the carrier 2 and intended to electrically contact the optoelectronic semiconductor chips 5 , and initially embedded into the resist 17 , can be uncovered . The optoelectronic semiconductor chips 5 can be connected to the contact pads 19 by wire bonding .

[0056] In a further method step, which can be called a second grinding step, grinding the converter material 8 is performed globally at the second emission faces 9 , whereby excessive converter material 8 is removed . In this step a certain wavelength of electromagnetic radiation emitted at the second emission faces 9 can already be targeted at least roughly .

[0057] The invention has been illustrated and described in detail with the aid of the preferred exemplary embodiments . Nevertheless , the invention is not restricted to the examples disclosed . Rather, other variants may be derived therefrom by a person skilled in the art without departing from the protective scope of the invention .

[0058] REFERENCE SYMBOLS

[0059] 1 optoelectronic component

[0060] 2 carrier

[0061] 3 top side of the carrier

[0062] 4 bottom side of the carrier

[0063] 5 optoelectronic semiconductor chip

[0064] 6 first emission face of the optoelectronic semiconductor chip

[0065] 7 mount face of the optoelectronic semiconductor chip

[0066] 8 converter material

[0067] 9 second emission face of the converter material

[0068] 10 optoelectronic arrangement

[0069] 11 first spectrum

[0070] 12 second spectrum

[0071] 13 wavelength distribution map

[0072] 14 thickness map

[0073] 15 milling head

[0074] 16 further wavelength distribution map

[0075] 17 resist

[0076] 18 cavity

[0077] 19 contact pads

Claims

CLAIMS1. A method of producing an optoelectronic component (1) comprising the following method steps:- providing an optoelectronic arrangement (10) arranged on a top side (3) of a carrier (2) and comprising an optoelectronic semiconductor chip (5) arranged at the top side (3) of the carrier (2) and a converter material (8) arranged at the optoelectronic semiconductor chip (5) , wherein the optoelectronic semiconductor chip (5) is designed to emit electromagnetic radiation from a first wavelength range at a first emission face (6) , wherein the converter material (8) is arranged at the first emission face (6) of the optoelectronic semiconductor chip (5) and is designed to absorb electromagnetic radiation emitted by the optoelectronic semiconductor chip (5) and to emit electromagnetic radiation from a second wavelength range at a second emission face (9) , wherein the optoelectronic arrangement (10) is designed to emit electromagnetic radiation comprising a combined wavelength range composed of electromagnetic radiation from the first wavelength range and the second wavelength range,- generating a wavelength distribution map (13) of the optoelectronic arrangement (10) , wherein the wavelength distribution map (13) of the optoelectronic arrangement (10) comprises a spatially resolved distribution of wavelengths of electromagnetic radiation emitted at the second emission face (9) of the converter material (8) ,- generating a thickness map (14) based on the wavelength distribution map (13) , wherein the thickness map (14) comprises information about local changes of a converter material thickness with respect to the first emission face (9) of the optoelectronic semiconductor chip (5) dependent on variations of the wavelengths of the wavelength distribution map (13) and with respect to a targeted colorimetric locus of the combined wavelength range,- removing at least a part of the converter material (8) at the second emission face (9) based on the thickness map (14) .

2. The method according to claim 1, wherein removing of the converter material (8) at the second emission face (9) is performed by milling.

3. The method according to claim 2, wherein milling is performed by scanning a milling head (15) across the second emission face (9) .

4. The method according to one of the previous claims, wherein the wavelength distribution map (13) is generated by measuring photoluminescence intensities for different wavelengths at the second emission face (9) spatially resolved and mapping a peak wavelength for different areas of the second emission face (9) .

5. The method according to one of the previous claims, wherein the optoelectronic arrangement (10) comprises a plurality of optoelectronic semiconductor chips (5) arranged at the top side (3) of the carrier (2) each having a first emission face ( 6 ) , wherein providing the optoelectronic arrangement (10) comprises a step of arranging the converter material (8) at the first emission faces (6) of the optoelectronic semiconductor chips (5) simultaneously, wherein a separate wavelength distribution map (13) and a separate thickness map (14) are generated for each combination of an optoelectronic semiconductor chip (5) and the converter material (8) and the removing of at least a part of the converter material (8) at second emission faces (9) of the converter material (8) is performed based on the respective thickness maps (14) .

6. The method according to one of the previous claims, wherein providing the optoelectronic arrangement (10) comprises the following steps:- arranging the optoelectronic semiconductor chip (5) at the top side (3) of the carrier (2) ,- embedding the optoelectronic semiconductor chip (5) into a resist ( 17 ) ,- structuring the resist (17) such that a cavity (18) is formed at the first emission face (6) of the optoelectronic semiconductor chip (5) , wherein the first emission face (6) is uncovered by the resist (17) ,- arranging the converter material (8) in the cavity (18) and at the first emission face (6) of the optoelectronic semiconductor chip (5) .

7. The method according to claim 6 comprising the following additional steps:- grinding converter material (8) parts arranged above the cavity (18) with respect to the top side (3) of the carrier (2) to uncover the resist (17) ,- remove the uncovered resist (17) from the carrier (2) .

8. The method according to one of the previous claims, wherein grinding the converter material (8) globally at the second emission face (9) is performed prior to removing the converter material (8) at least partially at the second emission face (9) based on the thickness map (14) locally.

9. The method according to one of the previous claims, wherein the converter material (8) comprises at least one phosphor embedded into a matrix material or a ceramic phosphor .

10. The method according to one of the previous claims, wherein the matrix material comprises polysiloxane.

11. Optoelectronic component (1) comprising a carrier (2) with a top side (3) , an optoelectronic semiconductor chip (5) arranged at the top side (3) of the carrier (2) and a converter material (8) arranged at the optoelectronic semiconductor chip (5) ,wherein the optoelectronic semiconductor chip (5) is designed to emit electromagnetic radiation from a first wavelength range at a first emission face (6) , wherein the converter material (8) is arranged at the first emission face (6) of the optoelectronic semiconductor chip (5) and is designed to absorb electromagnetic radiation emitted by the optoelectronic semiconductor chip (5) and to emit electromagnetic radiation from a second wavelength range at a second emission face (9) , wherein the optoelectronic arrangement (10) is designed to emit electromagnetic radiation comprising a combined wavelength range composed of electromagnetic radiation from the first wavelength range and the second wavelength range, wherein the converter material (8) comprises a thickness with respect to first emission face (9) of the optoelectronic semiconductor chip (5) which is modulated across the second emission face (9) such that relative wavelength variations of electromagnetic radiation emitted in different areas of the first emission face (6) are compensated by the converter material (8) locally.

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