Optoelectronic component

Abstract

Optoelectronic device (100) comprising: - a semiconductor chip (4) capable of emitting primary radiation from the blue spectral range, - a conversion element (10) comprising exactly three phosphors, each capable of converting the primary radiation into secondary radiation, - wherein the first phosphor (1) is capable of emitting secondary radiation from the green spectral range, - wherein the second phosphor (2) is capable of emitting secondary radiation from the red spectral range, - wherein the third phosphor (3) is a potassium silicon fluoride phosphor and is capable of emitting secondary radiation from the red spectral range, - wherein the device (100) has a predetermined Ra value of at least 80 and a predetermined R9 value of at least 75, and wherein the device (100) is capable of emitting mixed white radiation.- wherein the specified Ra value and the specified R9 value are none other than a respective maximum that could be maximally achieved by varying the concentration of the third phosphor (3) relative to the total proportion of the proportions of the second and third phosphors (2,3), and - wherein exactly as much of the third phosphor (3) is added as is necessary to achieve the specified Ra value and the specified R9 value.

Description

The present invention relates to an optoelectronic component Optoelectronic components contain at least one conversion element that includes phosphors. For example, for the application of optoelectronic components in general lighting, it is advantageous if the CRI range is between CRI 80 and CRI 100. It is also beneficial if the phosphors exhibit the narrowest possible emission. In particular, narrowband phosphors that emit radiation from the red spectral range are advantageous. One possible narrowband phosphor is, for example, a potassium silicon fluoride phosphor. In combination with another phosphor that emits radiation from the green spectral range, a CRI 80 / 90 system can be assembled. However, this potassium silicon fluoride phosphor has disadvantages that can negatively impact its application. For example, at high excitation intensities, the potassium silicon fluoride phosphor exhibits saturation effects, leading to changes in parameters such as color coordinates, CRI, or R9. Compared to conventional phosphors, potassium silicon fluoride phosphor exhibits a long rise time to emission when the optoelectronic device is operated in PWM dimming mode (pulse-width modulation; rectangular pulses, for example, between zero current and the operating current, for brightness dimming, as an alternative to operation at low currents). This results in lower aging stability compared to optoelectronic devices with conventional phosphors, leading to more rapid aging of the optoelectronic device. Furthermore, such an optoelectronic device, which uses potassium silicon fluoride as the red component, has the disadvantage, particularly in the high CRI range (CR90+), that the CRI / R9 setting is difficult to achieve and may limit the usable CCT range. Documents US 2017 / 0 179 347 A1, US 2015 / 0 295 144 A1, JP 2016-027 644 A, EP 2 629 341 A1 and DE 10 2015 202 159 A1 each disclose a light-emitting component. One challenge to be solved is to provide an optoelectronic component that overcomes the disadvantages described above. This problem is solved by the subject matter with the features of independent claim 1. Advantageous embodiments and further developments of the subject matter are specified in the dependent claims and will become apparent from the following description and the drawings. The optoelectronic component comprises a semiconductor chip. The semiconductor chip is capable of emitting primary radiation from the blue spectral range. The optoelectronic component comprises a conversion element. The conversion element comprises exactly three phosphors. Each phosphor is capable of converting the primary radiation into secondary radiation. The three phosphors are a first phosphor, a second phosphor, and a third phosphor. The first phosphor is capable of emitting secondary radiation from the green spectral range. The second phosphor is capable of emitting secondary radiation from the red spectral range. The third phosphor is a potassium silicon fluoride phosphor. The third phosphor is capable of emitting radiation from the red spectral range. The component has an Ra value and an R9 value. The Ra value is at least 80. The R9 value is at least 75.The component is capable of emitting mixed white radiation. In particular: For an Ra value of 80, an R9 value of > 0. For an Ra value of 90, an R9 value of > 90, especially R9 > 95. For an Ra value of 97, an R9 value of > 90, especially R9 > 95. In this context, "capable" means that, particularly during operation of the optoelectronic component, it emits mixed white radiation. In other words, the primary radiation from the semiconductor chip is not completely converted into secondary radiation; rather, the mixed white radiation is a sum of the primary and secondary radiation from the three phosphors. The fact that the phosphors are capable of emission means that they are designed to absorb and / or transmit primary radiation and emit secondary radiation. They emit the secondary radiation, in particular, during the operation of the optoelectronic component. It should be noted here that the term component refers not only to finished components, such as light-emitting diodes (LEDs) or laser diodes, but also to substrates and / or semiconductor layers. Thus, for example, a composite of a copper layer and a semiconductor layer can already constitute a component and be part of a larger, higher-level component, which may, for example, also have electrical connections. The optoelectronic component according to the invention can, for example, be a thin-film semiconductor chip, in particular a thin-film LED chip. Here and in the following, color specifications relating to emitting phosphors refer to the respective spectral range of electromagnetic radiation. The fact that the first phosphor is capable of emitting secondary radiation from the green spectral range refers here in particular to wavelengths or peak wavelengths in the range of 500 nm to 580 nm. The fact that the second and / or third phosphor is / are capable of emitting secondary radiation from the red spectral range refers here in particular to wavelengths or peak wavelengths between 580 nm and 650 nm. The fact that the semiconductor chip is capable of emitting primary radiation from the blue spectral range refers in particular to wavelengths or peak wavelengths from 430 nm to 470 nm. The component is capable of emitting white mixed radiation. Mixed radiation here refers specifically to the sum of primary and secondary radiation. The component thus exhibits partial conversion. Here and in the following, white mixed radiation can be defined as light with a color coordinate that corresponds to that of a Planckian blackbody radiator or deviates from the color coordinate of a Planckian blackbody radiator by less than 0.07, and preferably by less than 0.05, for example, 0.03, in Cx and / or Cy color coordinates. Furthermore, a luminous impression, here and in the following, can be produced by light having a color rendering index (CRI) of greater than or equal to 70, preferably greater than or equal to 80, and particularly preferably greater than or equal to 90 or 95, as is known to those skilled in the art. According to at least one embodiment, the optoelectronic component is an inorganic light-emitting diode, or LED for short. According to at least one embodiment, the optoelectronic device comprises a semiconductor chip. The semiconductor chip is capable of emitting primary radiation from the blue spectral range. In particular, the semiconductor chip emits primary radiation from the blue spectral range during operation of the device. The semiconductor chip comprises, in particular, a sequence of semiconductor layers. The sequence of semiconductor layers comprises semiconductor materials. The sequence of semiconductor layers is preferably based on a III-V compound semiconductor material. The semiconductor material is, for example, a nitride compound semiconductor material such as AlnIn1-n-mGamN, where 0 ≤ n ≤ 1, 0 ≤ m ≤ 1, and n + m ≤ 1. Preferably, for at least one layer or for all layers of the semiconductor layer sequence, the following apply: 0 < n ≤ 0.8, 0.4 ≤ m < 1, and n + m ≤ 0.95, as well as 0 < k ≤ 0.5. The semiconductor layer sequence can contain dopants as well as additional components.For the sake of simplicity, however, only the essential components of the crystal lattice of the semiconductor layer sequence, i.e. Al, Ga, In or N, are specified, even though these may be partially replaced and / or supplemented by small amounts of other substances. The semiconductor layer sequence can, for example, have a conventional pn junction, a double heterostructure, a single quantum well structure, or a multiple quantum well structure as its active region. In addition to the active region, the semiconductor layer sequence can include further functional layers and regions, such as p- or n-doped charge carrier transport layers (i.e., electron or hole transport layers), p- or n-doped confinement or cladding layers, buffer layers, and / or electrodes, as well as combinations thereof. Such structures in the active region or the further functional layers and regions are known to those skilled in the art, particularly with regard to their structure, function, and design, and are therefore not described in detail here. According to at least one embodiment, the component includes a conversion element. The conversion element comprises at least three phosphors. In particular, the conversion element comprises exactly three phosphors. The three phosphors are a first phosphor, a second phosphor, and a third phosphor. Each of the phosphors is capable of converting the primary radiation emitted by the semiconductor chip into secondary radiation. In other words, the respective phosphors are configured to convert the primary radiation emitted by the semiconductor chip into secondary radiation during operation of the component. Preferably, the conversion element is arranged in the primary radiation path. The conversion element is capable of partial conversion. In other words, the primary radiation is not completely converted into secondary radiation, but rather the total radiation emitted from the component is a sum of primary and secondary radiation.In particular, the total radiation is white mixed radiation. According to at least one embodiment, the component has a Ra value. The color rendering index Ra (or CRI) is a metric used to describe the quality of color rendering by light sources. The subscript 'a' in the formula symbol represents the general color rendering index, which is calculated as the average of the first eight test colors. According to at least one embodiment, the Ra value is at least 80. In particular, the Ra value is greater than or equal to 90, preferably greater than or equal to 91, 92, 93, 94, 95, 96, 97, 98 and / or 99. Additionally, the component has an R9 value. Of the 14 test colors specified in DIN, only the first eight (mixed colors) are included in the RA (CRI). The ninth test color is saturated red. The R9 value is therefore a measure of the red component in the spectrum. The R9 value indicates a higher color rendering index for saturated red. According to at least one embodiment, the R9 value is at least 75. Preferably, the R9 value is greater than or equal to 90, 91, 92, 93, 94, 95, 96, 97, 98 or 99. According to at least one embodiment, the dominance wavelength λdom of the blue spectral region of the semiconductor chip is smaller than 455 nm, 450 nm, 454 nm, or 445 nm. The dominance wavelength can also be the peak wavelength λpeak. The dominance wavelength, or dominant wavelength, is specifically the wavelength that results from the intersection of the spectral color line of the CIE standard chromaticity diagram with a straight line, where this straight line, originating from the white point in the CIE standard chromaticity diagram, passes through the actual chromaticity point of the radiation. In general, the dominant wavelength, or dominance wavelength, is different from the principal peak wavelength. According to at least one embodiment, the conversion element comprises a first phosphor. The first phosphor is capable of emitting secondary radiation from the green spectral range. According to at least one embodiment, the first phosphor is selected from the following group or combinations thereof: yttrium aluminum gallium garnet, lutetium aluminum garnet, lutetium aluminum gallium garnet, lutetium yttrium aluminum garnet, orthosilicate, nitridorthosilicate. The yttrium aluminum gallium garnet phosphor can, for example, be YaGaG. The yttrium aluminum gallium garnet phosphor can have the structural formula Y3(Al,Ga)5O12:Ce. Lutetium aluminum garnet can be LuAG. Lutetium aluminum garnet can have the structural formula Lu3Al5O12:Ce. Lutetium aluminum gallium garnet can, for example, be LuAGaG. Lutetium aluminum gallium garnet can have the structural formula Lu3(Al,Ga)5O12:Ce. Lutetium-yttrium aluminum garnet can be, for example, LuYAG. Lutetium-yttrium aluminum garnet can have the structural formula (Lu,Y)3Al5O12:Ce. Nitrido orthosilicates can be, for example, AE2-x-aRExEuaSiO4-xNx or AE2-x-aRExEuaSi1-yO4-x-2yNx with RE = rare earth metal and AE = alkaline earth metal or (Ba,Sr,Ca,Mg)2SiO4:Eu2+. The first, second and / or third phosphor is preferably selected from the following group, provided that these phosphors exhibit emission in the corresponding spectral range: Eu2+-doped nitrides such as (Ca,Sr)AlSiN3:Eu2+, Sr(Ca,Sr)Si2Al2N6:Eu2+, (Sr,Ca)AlSiN3*Si2N2O:Eu2+, (Ca,Ba,Sr)2Si5N8:Eu2+, (Sr,Ca)[LiA13N4]:Eu2+; Garnets from the general system (Gd,Lu,Tb,Y)3(Al,Ga,D)5(O,X)12:RE with X = halide, N or divalent element, D = trivalent or tetravalent element and RE = rare earth metals such as Lu3(All-xGax)5Ol2:Ce3+, Y3(Al1-xGax)5O12:Ce3+; Eu2+-doped sulfides such as (Ca,Sr,Ba)S:Eu2+; Eu2+-doped SiONe such as (Ba,Sr,Ca)Si2O2N2:Eu2+; SiAlONe from the system LixMyLnzSi12-(m+n)Al(m+n)OnN16-n; beta-SiAlONe from the system Si6-xAlzOyN8-y:REz with RE = rare earth metals; Nitrido orthosilicates such as AE2-x-aRExEuaSiO4-xNx or AE2-x-aRExEuaSi1-yO4-x-2yNx with RE = rare earth metal and AE = alkaline earth metal or like (Ba,Sr,Ca,Mg)2SiO4:Eu2+; chlorosilicates such as Ca8Mg(SiO4)4Cl2:Eu2+;Chlorophosphates such as (Sr,Ba,Ca,Mg)10(PO4)6Cl2:Eu2+; BAM phosphors from the BaO-MgO-Al2O3 system such as BaMgAl10O17:Eu2+; halophosphates such as M5(PO4)3(Cl,F):(Eu2+,Sb2+,Mn2+); SCAP phosphors such as (Sr,Ba,Ca)5(PO4)3Cl:Eu2+. Furthermore, so-called quantum dots can also be incorporated as converter material. Quantum dots in the form of nanocrystalline materials containing a group II-VI compound and / or a group III-V compound and / or a group IV-VI compound and / or metal nanocrystals are preferred. The phosphor can also have a quantum well structure and be epitaxially grown. According to at least one embodiment, the conversion element comprises a second phosphor. The second phosphor is capable of emitting radiation from the red spectral range. In particular, the second phosphor is M₂Si₅N₈ or a strontium calcium aluminum silicon nitride. M comprises at least Eu and additionally Ca, Sr, and / or Ba. In particular, M is a combination of Ca, Sr, Ba, and Eu. M can also be Ca, Sr, or Ba, wherein M additionally has a doping, for example, with Eu or Ce. The phosphor is doped. The doping is particularly with Eu. The strontium calcium aluminum silicon nitride phosphor can be an Eu²⁺-doped nitride, such as (Ca,Sr)AlSiN₃:Eu²⁺, Sr(Ca,Sr)Si₂Al₂N₆:Eu²⁺, or (Sr,Ca)AlSiN₃*Si₂N₂O:Eu²⁺. According to at least one embodiment, the component includes a third phosphor. The third phosphor is a potassium silicon fluoride phosphor. In particular, the potassium silicon fluoride phosphor is K₂SiF₆:Mn. According to at least one embodiment, the second phosphor has a wider half-value width than the third phosphor. In particular, the second phosphor is broadband, whereas the third phosphor is narrowband. According to at least one embodiment, the second phosphor has a half-width between 60 nm and 90 nm. According to at least one embodiment, the third phosphor has a half-width between 20 nm and 50 nm. A narrowband phosphor, in particular, has half-widths in the range of 20 nm and 50 nm. The potassium silicon fluoride (KSF) phosphor has a line-like spectrum consisting of several emission lines, each with a half-width of only a few nm. An imaginary envelope encompassing all individual lines would have a spectral width of approximately 30 nm. Potassium silicon fluoride phosphors exhibit negative intrinsic properties. While these negative properties can be improved, they cannot be completely eliminated. Therefore, potassium silicon fluoride phosphors are currently used only to a limited extent, as their application in optoelectronic components is limited by operating currents and temperatures. The inventors have now recognized that these disadvantages of the potassium silicon fluoride phosphor can be reduced or avoided by adding a second phosphor that also emits radiation from the red spectral range. Specifically, this second phosphor is a stable nitride phosphor. By adding a second phosphor, the majority of the conversion in the red spectral range can be handled by the second phosphor, which does not exhibit the described negative properties of the potassium silicon fluoride phosphor. In particular, only the amount of potassium silicon fluoride phosphor required to meet the CRI / R9 requirement is added. This dilution effect also reduces the impact of the negative properties of the third phosphor on the overall phosphor system. The addition of a broadband second phosphor does not contradict the aforementioned advantages of narrowband third phosphors. Using narrowband third phosphors as the long-wavelength red component is advantageous in terms of efficiency, as, for example, less red is present in the low-lumen range. The additional, short-wavelength red phosphor can certainly be broadband. Furthermore, the addition of the second phosphor increases flexibility in the selection of the first phosphor and the semiconductor chip used, particularly in high-CRI applications. The inventors recognized that without the second phosphor, only a few systems could achieve the claimed Ra and R9 values. Compared to components with exactly two phosphors, for example, a first phosphor and a third phosphor (a potassium strontium fluoride phosphor), such components require semiconductor chips with primary radiation in the long blue spectral range. This is because a single phosphor cannot completely bridge the spectral gap between the blue semiconductor chip emission and the red-emitting potassium silicon fluoride phosphor. The resulting spectral gap prevents high Ra values ​​(CRI). This can only be achieved by combining a long-wavelength green-emitting first phosphor with a very long-wavelength blue-emitting semiconductor chip. The inventors have now realized that by adding a second phosphor emitting radiation from the red spectral range, virtually unlimited combination possibilities arise between the phosphors, potassium silicon fluoride, and a semiconductor chip emitting radiation from the blue spectral range. The second phosphor fills the spectral gap between the first and third phosphors, thus allowing the use of short-wavelength first phosphors and correspondingly short-wavelength semiconductor chips. With the optoelectronic component described here according to the invention, high Ra / R9 values ​​with spectral efficiencies can be achieved that are significantly higher than those of conventional optoelectronic components. According to at least one embodiment, the proportion of the potassium silicon fluoride phosphor is between 55 wt% and 82 wt%, in particular between 55 wt% and 60 wt%, based on the total proportion of the second and third phosphors. However, a more highly doped KSF derivative is also conceivable, the absorption of which would then be higher and thus lower the concentrations required. According to at least one embodiment, the proportion of the potassium silicon fluoride phosphor is between 80 wt-% and 84 wt-% based on the total proportion of the second and third phosphors. According to at least one embodiment, the minimum proportion of the potassium silicon fluoride phosphor is between 53 wt% and 67 wt%, based on the total proportion of the second and third phosphors. Here, "minimal proportion" means the proportion of the third phosphor in the red component required to generate the necessary Ra and R9 values ​​of the component. Regarding the proportion of the third phosphor in the system, while its mass fraction is high, its spectral contribution to the white spectrum is rather small. This is primarily due to the poor absorption properties of the third phosphor. According to at least one embodiment, the first phosphor is a yttrium aluminum gallium garnet and the second phosphor is either M2Si5N8 or a strontium calcium aluminum silicon nitride. According to at least one embodiment, the first phosphor is a lutetium yttrium aluminum garnet and the second phosphor is either M2Si5N8 or a strontium calcium aluminum silicon nitride. According to at least one embodiment, the first phosphor is a lutetium aluminum gallium garnet and the second phosphor is either M2Si5N8 or a strontium calcium aluminum silicon nitride. According to at least one embodiment, the first phosphor is a lutetium aluminum garnet and the second phosphor is either M2Si5N8 or a strontium calcium aluminum silicon nitride. In these embodiments, the third phosphor is in particular the potassium silicon fluoride phosphor (KSF). According to at least one embodiment, the first phosphor is an orthosilicate and the second phosphor is either M2Si5N8 or a strontium calcium aluminum silicon nitride. According to at least one embodiment, the first phosphor is a nitridodoorthosilicate and the second phosphor is either M2Si5N8 or a strontium calcium aluminum silicon nitride. In comparison to a binary system, for example a system consisting of a lutetium yttrium aluminum garnet as the green component and a potassium silicon fluoride (KSF) phosphor as the red component, the optoelectronic device described here has the advantageous properties described here. Further advantages and advantageous embodiments and further developments of the subject matter according to the invention will become apparent from the exemplary embodiments described below in conjunction with the figures. The figures show: Fig. 1A a schematic side view of an optoelectronic component according to one embodiment, Fig. 1B a schematic side view of an optoelectronic component according to one embodiment, Fig. 1C a schematic side view of an optoelectronic component according to one embodiment, Fig. 1D a schematic side view of an optoelectronic component according to one embodiment, Fig. 1E a schematic side view of an optoelectronic component according to one embodiment, Fig. 2 the LER as a function of Ra of a comparative and exemplary embodiment, Fig. 3 the illustration of the efficiency advantage of comparative and exemplary embodiments, Fig. 4A the dependence of R9 on Ra of a comparative example, Fig. 4B the dependence of R9 on Ra of exemplary embodiments, Fig. 5A the dependence of Ra on the concentration of the third phosphor according to one embodiment, Fig.5B the dependence of R9 on the concentration of the third phosphor according to an embodiment, Fig. 5C the efficiency advantages depending on the concentration of the third phosphor, and Fig. 6 a potassium silicon fluoride emission spectrum. In the exemplary embodiments and figures, identical or equivalent components are identified by the same reference numerals. The depicted elements and their relative sizes are not to be considered to scale. Furthermore, identical embodiments of phosphors are identified by the same abbreviated designations. Table 1 shows components according to several embodiments and a binary comparison example. These examples can be part of the embodiments shown in the following figures. Table 1 YAGaGM2Si5N8KSF YAGaGSCASNKSF> 445 LuAGM2Si5N8KSF LuAGSCASNKSF LuAGaGM2Si5N8KSF LuAGaGSCASNKSF> 445 LuYAGM2Si5N8KSF LuYAGSCASNKSF> 455 Orthosilicate M2Si5N8KSF Orthosilicate SCASNKSF Comparison LuYAG-KSF> 455 Fig. 1 shows a schematic side view of an optoelectronic component according to one embodiment. According to Fig. 1A, the optoelectronic component 100 has a conductor frame 9. Furthermore, the optoelectronic component has a support or substrate 5. A semiconductor chip 4 is arranged on the conductor frame 9. The semiconductor chip 4 has a sequence of semiconductor layers. The semiconductor chip is configured to emit radiation from the blue spectral range, for example, with a dominant wavelength of 450 nm. The semiconductor chip 4 is arranged within a recess 7. The recess 7 is part of a housing 6. The recess 7 can be filled with a potting compound. The potting compound can have a matrix material 8. The first phosphor, the second phosphor, and the third phosphor can be embedded in the matrix material. The embedding can be homogeneous or inhomogeneous. Furthermore, other particles can be embedded in the potting compound. These other particles can be, for example, scattering particles (not shown here).The matrix material can be silicone or epoxy resin. The conversion element surrounds the semiconductor chip 4 in a materially and form-fitting manner and converts at least partially the primary radiation emitted by the semiconductor chip 4 into secondary radiation. The first phosphor 1 emits the primary radiation as secondary radiation from the green spectral range, the second phosphor 2 emits the primary radiation as secondary radiation from the red spectral range, in particular into broadband red spectral radiation, and the third phosphor 3 is in particular a potassium silicon fluoride phosphor. Narrowband can mean a full width at half maximum (FWHM) of 20 nm to 50 nm. The third phosphor 3 emits primary radiation as secondary radiation from the red spectral range, preferably in narrowband spectral radiation. The total radiation emitted from the component 100 is white mixed radiation 11. The component has a Ra value of at least 80 and an R9 value of at least 75. The R9 value of 75 refers in particular to a high-Ra solution with Ra > 90. For CRI 80, an R9 limit of > 0 is also practical. Figure 1B shows a schematic side view of an optoelectronic device according to one embodiment. Here, the semiconductor chip 4 is arranged on a support or substrate 5. The substrate can, for example, comprise one or more materials in the form of a layer, a plate, a film, or a laminate, selected from glass, quartz, plastic, metal, silicon, or a wafer. In particular, the substrate is a silicon wafer. The conversion element 10 is arranged on the main radiation surface 12 of the semiconductor chip 4. The conversion element 10 can comprise a matrix material 8 and the three phosphors 1, 2, and 3. The conversion element 10 can, for example, be prefabricated and applied to the main radiation surface 12 of the semiconductor chip 4 in a so-called pick-and-place process. Preferably, the side surfaces 13 of the semiconductor chip 4 are free of the conversion element of the device 100. Figure 1C shows a schematic side view of an optoelectronic component according to one embodiment. The semiconductor chip 4 is arranged on a substrate 5. The substrate can, for example, be a ceramic. The conversion element 10 surrounds the semiconductor chip 4 on all sides. The conversion element 10 can comprise at least three phosphors 1, 2, and 3. The conversion element 10 can be made of ceramic. Alternatively, the three phosphors 1, 2, and 3 are embedded in a matrix material 8, for example, silicone. Figure 1D shows a schematic side view of an optoelectronic component 100 according to one embodiment. Here, the semiconductor chip 4 is arranged on the substrate 5. A conversion element 10 is arranged in the beam path of the semiconductor chip 4. The conversion element has at least two sublayers. The first sublayer is located directly downstream of the semiconductor chip 4. The first sublayer comprises the first phosphor 1. The first phosphor 1 can be present without a matrix material 8 or embedded in a matrix material. In particular, the first sublayer is arranged directly on the main radiation surface 12 of the semiconductor chip 4. A second sublayer can follow the first sublayer. The second sublayer can comprise a mixture of a second phosphor 2 and a third phosphor 3. The second sublayer can be a ceramic, or the second and third phosphors can be dispersed in a matrix material 8, for example, silicone.The second sublayer is preferably directly subordinate to the first sublayer. Alternatively, the order of the first and second sublayers can also be reversed. In other words, the second sublayer can directly follow semiconductor chip 4, and the first sublayer then directly follows the second sublayer. Fig. 1E shows a schematic side view of an optoelectronic component 100 according to one embodiment. The semiconductor chip 4 is arranged on a substrate 5. The conversion element 10 has three sublayers. The first sublayer contains the first phosphor 1. The second sublayer contains the second phosphor 2. The third sublayer contains the third phosphor 3. The sublayers can be arranged sequentially away from the semiconductor chip 4 as follows: first sublayer, second sublayer, and third sublayer. Alternatively, the sequence in the direction away from the semiconductor chip can be: second sublayer, third sublayer, first sublayer. Alternatively, the sequence in the direction away from the semiconductor chip can be: third sublayer, first sublayer, second sublayer. Figure 2 shows the dependence of the efficiency LER (with the unit lumens per optical watt) on the Ra value. Comparative examples and embodiments are shown. Section 20 shows the comparative examples, and section 21 shows the optoelectronic component according to one embodiment. The comparison examples are specifically components that contain only two phosphors: a green-emitting phosphor and a red-emitting phosphor. None of the comparison examples contain a potassium silicon fluoride phosphor. The component according to the invention comprises at least three phosphors and was simulated at 4000 K, with peak wavelengths of 445, 450 and 455 nm. Compared to the comparative examples, the component according to the invention described here exhibits high light quality combined with high efficiency. Figure 3 shows the LER as a function of R9 as a simulation. The efficiency advantages of comparative examples (322) and embodiments (311, x) are shown. The comparative examples do not contain potassium silicon fluoride phosphor. The embodiments include potassium silicon fluoride. The simulation was performed at 4000 K, with a peak wavelength of 445 nm and a CRI greater than 92. The component according to the invention shows a high quality and a high LER value compared to the respective comparison example (see arrow 31 compared to arrow 32). Fig. 4A shows a simulation of R9 as a function of the R8 value of comparison examples at wavelengths of 445 nm, 450 nm and 455 nm. Furthermore, the "target square" is defined, i.e., the area that has an Ra value of at least 80 and an R9 value of at least 75. Here, a simulation of phosphor solutions with potassium silicon fluoride as the red component is shown in Fig. 4A, and for comparison, an optoelectronic component according to an embodiment shown in Fig. 4B. Fig. 4B shows the dependence of the R9 value on Ra at wavelengths of 445 nm, 450 nm and 455 nm for exemplary embodiments. A comparison of the two graphs in Fig. 4A and Fig. 4B clearly shows that a component according to the invention enables more and better combination possibilities of phosphor systems compared to the reference example with the required Ra and R9 values. Furthermore, the usable chip wavelength range is increased by the component according to the invention described here. Figures 5A to 5B show the dependence of the Ra value on the concentration of the third phosphor, c KSF, in %. Potassium silicon fluoride (KSF) is given here as the third phosphor in %. The percentage c KSF refers to the total proportion of the second and third phosphors. Figure 5C shows the efficiency LER as a function of the concentration of the third phosphor KSF in percent. Here, a conversion element 10 of an optoelectronic component 100, comprising a first, second, and third phosphor, was simulated. Figures 5A and 5B clearly show that a concentration of 100% KSF in the mixture is not necessary for sufficient color rendering. Equivalent color rendering can also be achieved with approximately 60 wt-% KSF and 40 wt-% of the second phosphor, with the added benefit of increased efficiency (see Figure 5C). Figure 5A shows a minimum KSF concentration of approximately 50 wt-%. The Ra value is maximum at approximately 80 wt-% KSF, based on the total proportion of the second and third phosphors. Fig. 5B shows the minimum KSF concentration of 65 wt-% for R9 = 80 and a maximum KSF concentration of 80 wt-% at a maximum R9 value of approximately 100. The graph in Fig. 5C shows that the lower the concentration of the third phosphor, the higher the spectral efficiency LER. Figure 6 shows a potassium silicon fluoride (KSF) emission spectrum. The intensity is shown as a function of wavelength. The inventors have recognized that maximum efficiency can be achieved by using a minimal concentration of the third phosphor in the optoelectronic component according to the embodiment. The embodiments and their features described in connection with the figures can also be combined with one another according to further embodiments, even if such combinations are not explicitly shown in the figures. Furthermore, the embodiments described in connection with the figures can have additional or alternative features as described in the general section. Reference symbol list 100 optoelectronic component 1 first phosphor 2 second phosphor 3 third phosphor 4 semiconductor chip 5 carrier or substrate 6 package 7 recess 8 matrix material 9 conductor frame 10 conversion element 11 total radiation, mixed radiation 12 main radiation face of the semiconductor chip 13 side faces of the semiconductor chip

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