Optoelectronic device and method for discriminating an optoelectronic device

Abstract

An optoelectronic component is proposed. According to one embodiment, the optoelectronic component comprises: a semiconductor chip, which is arranged to emit primary radiation having a first wavelength range during operation of the optoelectronic component; a component, which comprises an optically active material, wherein the component is at least partially arranged in a beam path of the semiconductor chip; and the optically active material is not arranged to be excited by the primary radiation having the first wavelength range. Furthermore, a method for identifying an optoelectronic component is proposed.

Description

Technical Field

[0001] An optoelectronic device is proposed. Furthermore, a method for identifying the optoelectronic device is proposed. Summary of the Invention

[0002] The objective is to provide an optoelectronic device that can be identified particularly easily. Another objective is to provide a method for identifying optoelectronic devices, which enables the identification of identifiable optoelectronic devices.

[0003] An optoelectronic device is proposed. For example, an optoelectronic device that emits radiation.

[0004] According to at least one embodiment, the optoelectronic device includes a semiconductor chip configured to emit primary radiation having a first wavelength range during operation of the optoelectronic device. The semiconductor chip can include an active layer sequence containing active regions capable of generating primary radiation during operation of the optoelectronic device. Herein and hereinafter, primary radiation refers to electromagnetic radiation of a first wavelength or first wavelength range emitted by the semiconductor chip. The semiconductor chip is, for example, a light-emitting diode (LED) chip or a laser diode (laser diode) chip.

[0005] According to at least one embodiment, the optoelectronic device includes a component comprising an optically active material. Specifically, the component comprises an optically active material and a matrix material. In particular, the optically active material is surrounded by the matrix material. The optically active material is particularly capable of being configured to absorb electromagnetic radiation, convert the wavelength or wavelength range of electromagnetic radiation, and emit electromagnetic radiation of the converted wavelength or wavelength range. For example, the optically active material includes or is composed of a luminescent material. In particular, the optically active material has a specific optical signature. The specific optical signature is, for example, a specific emission spectrum.

[0006] According to at least one embodiment, the component is at least partially disposed in the beam path of the semiconductor chip. In other words, at least a portion of the primary radiation emitted by the semiconductor chip strikes a portion of the component. Here, the component can be disposed directly downstream of the radiation exit surface of the semiconductor chip, such that the radiation from the semiconductor chip strikes the component directly. Here, the component can be disposed in direct contact with the semiconductor chip. Alternatively, the component and the semiconductor chip can be disposed spaced apart from each other. Here, the radiation from the semiconductor chip can be deflected by an optical element, for example, before striking the component.

[0007] According to at least one embodiment, the optically active material is not configured to be excited by primary radiation having a first wavelength range. In other words, the first wavelength range does not overlap with or substantially does not overlap with the absorption band of the optical material. Therefore, the optical material cannot or substantially cannot absorb the primary radiation of the semiconductor chip, and thus is not excited and does not emit electromagnetic radiation after being excited with wavelengths in the first wavelength range. In particular, the optically active material is characterized by having a wavelength-dependent reflectance or diffuse reflectance R(λ) of greater than or equal to 80%, preferably greater than or equal to 90%, and particularly preferably greater than or equal to 95% in the first wavelength range.

[0008] Alternatively or additionally, optically active materials exhibit low values ​​of the Kubelka-Munk function for wavelengths within a first wavelength range. The Kubelka-Munk function is a method for describing the relative absorption intensity of optically active and luminescent materials at different wavelengths. The Kubelka-Munk function can be derived from measurements of diffuse reflectance or reflectance. The results of diffuse reflectance measurements are converted into the Kubelka-Munk function KMF(λ) according to the following rule:

[0009] KMF(λ) = K(λ) / S(λ) = (1-R(λ)) 2 / (2R(λ)),

[0010] Where K(λ) describes the absorption of the luminescent material at wavelength λ, S(λ) describes the scattering properties of the luminescent material at wavelength λ, and R(λ) is the diffuse reflectance or reflectance measured at wavelength λ. In this context, a low value of KMF(λ) implies low absorption and low excitability of the optically active material.

[0011] According to at least one embodiment, the optoelectronic device includes: a semiconductor chip configured to emit primary radiation having a first wavelength range during operation of the optoelectronic device; and a component comprising an optically active material, wherein the component is at least partially disposed in the beam path of the semiconductor chip, and the optically active material is not configured to be excited by the primary radiation having the first wavelength range.

[0012] This optoelectronic device has a component containing an optically active material that is not activated by primary radiation from the semiconductor chip. Therefore, the optical properties of the optoelectronic device, particularly its emission spectrum and brightness, as well as its stability, remain unaffected within normal manufacturing tolerances. By using an optically active material in the optoelectronic device, its optical signature can be verified through subsequent spectral examination, thus enabling easy re-identification or authentication of the device. Furthermore, this optoelectronic device can be manufactured simply and at low cost.

[0013] According to at least one embodiment, the semiconductor chip emits primary radiation in the visible wavelength range. The first wavelength range therefore includes wavelengths from the visible wavelength range. In other words, the semiconductor chip emits primary radiation in the wavelength range from 365 nm to 750 nm, particularly from 415 nm to 750 nm. For example, the semiconductor chip emits primary radiation in the blue wavelength range, the green wavelength range, or the red wavelength range. For example, the semiconductor chip emits blue primary radiation with a wavelength of 450 nm.

[0014] According to at least one embodiment, the component includes at least one light-emitting material configured to at least partially convert primary radiation from a semiconductor chip into secondary radiation. Specifically, the light-emitting material converts the primary radiation from the semiconductor chip into secondary radiation having a wavelength range that is at least partially, and particularly quite different from, the first wavelength range of the primary radiation from the semiconductor chip. For example, the light-emitting material converts blue primary radiation into green, red, or yellow secondary radiation, or into secondary radiation in the near-infrared range.

[0015] The component can have exactly one, two, or more light-emitting materials that convert primary radiation from the semiconductor chip into secondary radiation. In particular, partial or complete conversion is possible. Therefore, the radiation emitted by the optoelectronic device can consist of primary and secondary radiation, or only secondary radiation. The color impression of the optoelectronic device can be modulated by the appropriate mixing of primary and / or secondary radiation.

[0016] According to at least one embodiment, the optoelectronic device emits radiation in the visible wavelength range during operation. The radiation emitted by the optoelectronic device during operation consists, for example, primary radiation from a semiconductor chip and secondary radiation from at least one light-emitting material. For example, the optoelectronic device emits blue primary radiation and / or red and / or green and / or yellow secondary radiation. In particular, the optoelectronic device emits white mixed light consisting of blue primary radiation and red and / or yellow and / or green secondary radiation.

[0017] According to at least one embodiment, the component includes, or is a semiconductor chip, an optical element, a vertices, a conversion layer, or a passivation layer.

[0018] Components shaped as optical elements are, for example, lenses, which can be used to focus or defocus radiation emitted by optoelectronic devices.

[0019] A component formed as a potting compound at least partially, and especially completely, surrounds a semiconductor chip. The potting compound serves to protect the semiconductor chip from external influences. In particular, the potting compound can be formed as a conversion potting compound. In other words, the potting compound can have one or more light-emitting materials.

[0020] The component formed as a conversion layer includes one or more light-emitting materials. The conversion layer can be directly disposed on the semiconductor chip or disposed spaced apart from the semiconductor chip.

[0021] Components forming passivation layers for semiconductor chips are particularly directly disposed on the semiconductor chip. Passivation layers are used to protect the semiconductor chip. For example, passivation layers do not contain light-emitting materials.

[0022] According to at least one embodiment, the optoelectronic device does not contain a semiconductor chip or an optically active element configured to excite the optically active material. In particular, the optoelectronic device does not contain a semiconductor chip or an optically active element configured to excite the optically active material. For example, the optically active element is an emitter or luminescent material that emits radiation (e.g., in the green or red wavelength range), especially secondary radiation. In other words, the optoelectronic device does not have a semiconductor chip and does not have an optically active element that emits wavelengths that the optically active material can absorb during operation of the optoelectronic device. Therefore, during operation of the optoelectronic device, no electromagnetic radiation with wavelengths capable of stimulating the optically active element is generated in the optoelectronic device. Thus, the optically active material is not activated during operation of the optoelectronic device and advantageously, the optical properties of the optoelectronic device are not affected.

[0023] According to at least one embodiment, the optically active material substantially does not absorb radiation in the visible spectrum.

[0024] The word “basically” here and below is particularly useful in indicating that the presence of optically active materials is imperceptible to human observers.

[0025] In other words, the optically active material has a wavelength-dependent reflectance or diffuse reflectance R(λ) of greater than or equal to 80%, preferably greater than or equal to 90%, and particularly preferably greater than or equal to 95% in the visible spectrum. Therefore, the optically active material is advantageously suitable for: not affecting the optical properties of optoelectronic devices that emit radiation in the visible spectrum.

[0026] According to at least one embodiment, the optically active material is substantially transparent to radiation emitted by the optoelectronic device during operation. In other words, the optically active material transmits all wavelengths emitted by the optoelectronic device during its operation, which are present in the optoelectronic device. In particular, the radiation emitted by the optoelectronic device during operation is substantially not absorbed, reflected, and / or scattered by the optically active material. The optically active material is therefore advantageously suited to: not affecting the optical properties of the optoelectronic device that emits radiation in the visible spectrum.

[0027] According to at least one embodiment, the optically active material substantially does not affect the optical properties of the optoelectronic device. In particular, the optically active material cannot be activated by radiation emitted by the optoelectronic device during operation, thus the emission spectrum of the optoelectronic device remains unaffected during operation. Specifically, the emission spectrum of the optoelectronic device neither deforms nor degrades system efficiency during operation. Furthermore, the optically active material has substantially no effect on scattering in the optoelectronic device. In particular, by introducing the optically active material into the components of the optoelectronic device, a small amount of scattering is induced, thereby the color coordinates and brightness of the optoelectronic device remain unaffected.

[0028] According to at least one embodiment, the optically active material is configured to absorb radiation in a second wavelength range and convert it into secondary radiation. Specifically, the optically active material converts radiation in the second wavelength range into secondary radiation having a wavelength range that is at least partially, and particularly, entirely different from the second wavelength range. Specifically, the optically active material has a wavelength-dependent reflectance or diffuse reflectance R(λ) of less than or equal to 70%, preferably less than or equal to 50%, and particularly preferably less than or equal to 30% in the second wavelength range. Alternatively or additionally, the optically active material has a high value of the Kuberca-Monk function for the wavelengths in the second wavelength range. In this context, a high value of KMF(λ) implies high absorption and high excitability of the optically active material.

[0029] According to at least one embodiment, the ratio of the Kubelka-Munk function of the optically active material in the second wavelength range to that in the first wavelength range is greater than or equal to 10, particularly greater than or equal to 100, and preferably greater than or equal to 1000. This Kubelka-Munk function ratio means that the Kubelka-Munk function of the optically active material in the second wavelength range is much larger than that in the first wavelength range. In other words, the absorption of the optically active material is significantly stronger in the second wavelength range compared to the first wavelength range.

[0030] According to at least one embodiment, the second wavelength range is at least partially, and in particular completely, different from the first wavelength range of the primary radiation from the semiconductor chip. According to at least one further embodiment, the second wavelength range is at least partially, and in particular completely, different from the radiation emitted by the optoelectronic device during operation. Therefore, the optically active material is configured to convert wavelengths not emitted by the optoelectronic device during operation.

[0031] According to at least one embodiment, the second wavelength range is shorter than the first wavelength range, and the optically active material converts radiation in the second wavelength range into radiation with a longer wavelength. In other words, a downconversion of the radiation in the second wavelength range occurs. For example, the optically active material converts radiation in the blue or ultraviolet wavelength range into radiation in the visible and / or near-infrared wavelength range, particularly into radiation in the green, yellow, and / or red wavelength range.

[0032] According to at least one embodiment, the optically active material converts radiation with wavelengths less than 415 nm into radiation in the visible wavelength range.

[0033] According to at least one embodiment, the optically active material converts radiation with wavelengths less than 365 nm, especially less than 300 nm, into radiation in the visible wavelength range.

[0034] Optically active materials that convert radiation in the second wavelength range into radiation with longer wavelengths are preferably excited only by ultraviolet radiation and exhibit emission in the visible range. However, when radiation is emitted during the operation of optoelectronic devices, especially in the visible wavelength range, such optically active materials are not excited and the optical properties of the optoelectronic devices are thus unaffected.

[0035] According to at least one embodiment, the second wavelength range is longer than the first wavelength range, and the optically active material converts radiation in the second wavelength range into radiation with shorter wavelengths. In other words, an upconversion occurs in the radiation of the second wavelength range. In particular, the optically active material converts infrared radiation into radiation in the visible wavelength range. For example, the optically active material converts radiation with wavelengths greater than 750 nm into radiation in the visible wavelength range. Such an optically active material is excited only by infrared radiation and exhibits emission in the visible range. However, when radiation is emitted during the operation of the optoelectronic device, especially radiation in the visible wavelength range, this optically active material is not excited, and thus the optical properties of the optoelectronic device are unaffected.

[0036] According to at least one embodiment, the optically active material has a re-identifiable emission spectrum. The emission spectrum of the optically active material has at least one, and particularly at least two, characteristic emission bands that have a high re-identification value by means of spectroscopic methods. In particular, the optically active material has a line spectrum. The line spectrum has multiple characteristic emission bands, and particularly multiple narrow emission bands. Therefore, line emitters are particularly advantageously suitable as optically active materials.

[0037] According to at least one embodiment, the proportion of the optically active material in the component is from 0.004 wt% to 1 wt% (including boundary values), particularly greater than or equal to 0.05 wt% and less than or equal to 1 wt%, for example 0.05 wt%, 0.25 wt%, or 1 wt%. Due to the low concentration of the optically active material in the component, the optically active material has virtually no effect on scattering in the optoelectronic device and does not affect the color coordinates and brightness of the optoelectronic device.

[0038] According to at least one embodiment, the optically active material is selected from: CeMgAl 11 O 19 :Tb、BaMgAl 10 O 17 :Eu、LaPO4:Tm、YBO3:Tm、LaPO4:Ce,Tb、LaMgB5O 10 Ce,Tb,LaMgAl 11 O 19 Ce, Tb, Y₂O₃:Eu, (Y,Gd)BO₃:Eu, YVO₄:Eu, and combinations thereof. These materials exhibit good miscibility with standard luminescent and matrix materials, and are therefore particularly compatible with established methods and processes used to manufacture optoelectronic devices. Furthermore, these materials are stable and low-cost.

[0039] According to at least one embodiment, the optically active material includes CeMgAl 11 O 19 :Tb、BaMgAl 10 O 17 Eu and / or Y₂O₃:Eu or CeMgAl 11 O 19 :Tb、BaMgAl 10 O 17 Composed of Eu and / or Y₂O₃:Eu. Optically active material CeMgAl 11 O 19 :Tb、BaMgAl 10 O 17 Eu and Y₂O₃:Eu exhibits significantly higher wavelength-dependent reflectance or diffuse reflectance R(λ) exceeding 95% across the entire wavelength range of 450 nm to 700 nm. BaMgAl 10 O 17 Eu exhibits a reflectivity of less than 70% for wavelengths below 410 nm, CeMgAl 11 O 19Tb exhibits less than 70% reflectance for wavelengths below 320 nm, and Y₂O₃:Eu exhibits less than 70% reflectance for wavelengths below 270 nm. Therefore, these optically active materials are particularly advantageously configured to not affect the optical properties of optoelectronic devices during operation while maintaining good excitation capability for wavelengths in the ultraviolet range.

[0040] A method for identifying optoelectronic devices is also proposed. Preferably, the method described herein is used to identify optoelectronic devices according to the above embodiments. In particular, all embodiments for optoelectronic devices are also applicable to the method, and vice versa.

[0041] According to at least one embodiment, a method for identifying an optoelectronic device includes providing the optoelectronic device. The features of the optoelectronic device have been described in conjunction with the optoelectronic device itself, and are also applicable to the optoelectronic device in the method for identifying the optoelectronic device.

[0042] According to at least one embodiment, the method includes irradiating the optoelectronic device from the outside with electromagnetic radiation in a second wavelength range. Irradiation of the optoelectronic device from the outside is performed, in particular, via an external radiation source disposed outside the optoelectronic device. Specifically, the external radiation source is not a component, part, or element of the optoelectronic device. The external radiation source is positioned relative to the optoelectronic device such that the radiation from the external radiation source strikes at least a part of the optoelectronic device. In other words, at least a part of the optoelectronic device is disposed in the beam path of the external radiation source. For example, the external radiation source is an ultraviolet lamp or an infrared lamp.

[0043] According to at least one embodiment, the method includes detecting secondary radiation emitted by an optoelectronic device. The secondary radiation emitted by the optoelectronic device includes or consists of secondary radiation generated by converting radiation in a second wavelength range through an optically active material in the optoelectronic device. Optionally, the secondary radiation emitted by the optoelectronic device may also include secondary radiation generated by a luminescent material. If the method for identifying the optoelectronic device is performed during operation of the device, it is additionally possible that the secondary radiation emitted by the optoelectronic device also includes primary radiation from a semiconductor chip.

[0044] The emitted secondary radiation is detected, particularly via an external detection element located outside the optoelectronic device. In particular, the external detection element or detector is configured such that the emitted secondary radiation strikes or is guided onto the detector.

[0045] According to at least one embodiment, a method for identifying an optoelectronic device includes providing the optoelectronic device, irradiating the optoelectronic device from the outside with electromagnetic radiation in a second wavelength range, and detecting secondary radiation emitted by the optoelectronic device.

[0046] This method is particularly suitable for: spectrally verifying optoelectronic devices via optical signatures of optically active materials in the components of the device. In particular, this method can be performed with exceptional simplicity.

[0047] According to at least one embodiment, the second wavelength range is shorter than the first wavelength range. In particular, the external radiation source emits radiation in the blue or ultraviolet wavelength range. For example, the second wavelength range includes wavelengths less than 415 nm or less than 365 nm, especially less than 300 nm. Specifically, the optically active material converts the short-wavelength radiation of the second wavelength range into longer-wavelength radiation, particularly into radiation in the visible and / or near-infrared wavelength range. Therefore, optoelectronic devices can be identified by irradiation, for example, with ultraviolet radiation.

[0048] According to at least one embodiment, the second wavelength range is longer than the first wavelength range. In particular, the external radiation source emits radiation in the infrared wavelength range. For example, the second wavelength range includes wavelengths greater than 750 nm. Specifically, the optically active material converts the long-wavelength radiation of the second wavelength range into shorter-wavelength radiation, particularly into radiation in the visible wavelength range. Therefore, optoelectronic devices can be identified by irradiation, for example, with infrared radiation.

[0049] According to at least one embodiment, optoelectronic devices can be identified based on secondary radiation. Here, the secondary radiation includes an optical signature of the optically active material. Based on this optical signature, the optoelectronic device can be assigned. In particular, the optical signature includes a characteristic emission band of the optically active material, which is generated only by radiative excitation in a second wavelength range. For example, the characteristic emission band of the optically active material is a line in a line spectrum.

[0050] It is feasible for the secondary radiation to include additional emission bands, such as the emission band of a similarly excited luminescent material in an optoelectronic device. This would result in the emission band overlapping with the characteristic emission band of the optically active material, where the characteristic emission band of the optically active material can be clearly assigned in the overlapping spectrum.

[0051] If the method for identifying optoelectronic devices is performed during the operation of the optoelectronic devices, the secondary radiation emitted by the optoelectronic devices includes, in addition to the characteristic emission bands of the optically active materials, secondary radiation emitted during the operation of the optoelectronic devices, which consists, for example, the primary radiation from the semiconductor chip and the secondary radiation from the conversion. In this case, the characteristic emission bands of the optically active materials can also be clearly assigned in the overlapping spectrum.

[0052] According to at least one embodiment, the method for identifying the optoelectronic device is not performed during the operation of the optoelectronic device. In other words, the optoelectronic device is turned off during identification. In a turned-off optoelectronic device, the total proportion of emitted radiation is significantly lower. This results in a better signal-to-noise ratio and improved identification efficiency.

[0053] According to at least one embodiment, the optically active material converts radiation in a second wavelength range into radiation in the visible wavelength range, particularly in the green, yellow, and / or red wavelength range. Therefore, the detection of secondary radiation can be particularly simple and low-cost.

[0054] Other advantageous embodiments, designs, and improvements of optoelectronic devices and methods for identifying optoelectronic devices are derived from the following embodiments illustrated in conjunction with the accompanying drawings. Attached Figure Description

[0055] Figures 1 to 3 Schematic diagrams of optoelectronic devices according to different embodiments are shown.

[0056] Figure 4 A structure for identifying optoelectronic devices according to one embodiment is shown.

[0057] Figure 5 The optically active material CeMgAl is shown. 11 O 19 The absorption and emission spectra of Tb

[0058] Figure 6A and Figure 6B The emission spectra of optoelectronic devices after external excitation are shown according to different embodiments and comparative examples.

[0059] Figure 7A and Figure 7B A comparison of the integrated emission spectra of optoelectronic devices after external excitation according to different embodiments is shown.

[0060] Figure 8 The color coordinates of optoelectronic devices according to different embodiments and comparative examples are shown.

[0061] Figure 9 The relative brightness of optoelectronic devices according to different embodiments is shown.

[0062] Figure 10 The color rendering index and R9 value of optoelectronic devices according to different embodiments are shown.

[0063] Figure 11 The emission spectra of optoelectronic devices according to different embodiments are shown.

[0064] Figures 12A to 12C The emission spectrum after external excitation is shown according to one embodiment of a method for identifying optoelectronic devices.

[0065] Figure 13 The reflection curves of the optically active materials according to different embodiments are shown, and

[0066] Figure 14 The relative Kuberca-Monk function of optically active materials according to different embodiments and comparative examples is shown.

[0067] Identical, similar, or functionally equivalent elements are given the same reference numerals in the accompanying drawings. The size proportions of the elements shown in the drawings should not be considered to be proportional. Rather, for better visibility and / or better understanding, individual elements, especially layer thicknesses, may be shown exaggeratedly. Detailed Implementation

[0068] Figure 1-3 Schematic cross-sectional views of optoelectronic device 1 are shown. Optoelectronic device 1 includes a semiconductor chip 2 having an active layer sequence and an active region (not explicitly shown) that emits primary radiation in a first emission wavelength range during operation of optoelectronic device 1. Specifically, the primary radiation is electromagnetic radiation in the visible wavelength range. Semiconductor chip 2 emits, for example, in the blue wavelength range, such as a wavelength of 450 nm. The primary radiation is emitted through the radiation exit surface 3 of semiconductor chip 2 and forms a beam path.

[0069] Figure 1-3 The optoelectronic device further includes components 4. Components 4 are respectively disposed in the beam path of the primary radiation of the semiconductor chip 2, such that at least a portion of the primary radiation hits component 4. Therefore, component 4 can be directly applied to the semiconductor chip 2, particularly to the radiation exit surface 3. Figure 1 and 2 ), or spaced apart from semiconductor chip 2 ( Figure 3 ). Figure 1 Component 4 can be, for example, a passivation layer or a conversion layer of the semiconductor chip 2. Figure 2 In this part, component 4 is formed into a potting compound. This potting compound can also be a conversion potting compound. Figure 3 The components can be, for example, optical elements (such as a conversion layer or lens spaced apart from the semiconductor chip 2).

[0070] Component 4 includes an optically active material that is not configured to be excited by primary radiation from the semiconductor chip 2 within a first wavelength range. Specifically, the optically active material has a wavelength-dependent reflectance or diffuse reflectance R(λ) greater than or equal to 80%, preferably greater than or equal to 90%, and particularly preferably greater than or equal to 95% within the first wavelength range, especially in the visible wavelength range. The optically active material is particularly selected from CeMgAl. 11 O 19 :Tb、BaMgAl 10 O 17 :Eu、LaPO4:Tm、YBO3:Tm、LaPO4:Ce,Tb、LaMgB5O 10 Ce,Tb,LaMgAl 11 O 19 Ce,Tb, Y₂O₃:Eu, (Y,Gd)BO₃:Eu, YVO₄:Eu, and combinations thereof. For example, optically active materials include CeMgAl. 11 O 19 :Tb or is composed of it.

[0071] In particular, component 4 also includes a matrix material in which an optically active material is embedded. Optionally, component 4 may include one or more luminescent materials configured to convert primary radiation in a first wavelength range into secondary radiation.

[0072] Figure 4 The structure of the method for identifying optoelectronic devices is shown below. Figure 2 The optoelectronic device 1 of the embodiment. An external radiation source 5 emitting electromagnetic radiation in a second wavelength range is disposed outside the optoelectronic device 1. The external radiation source 5 is disposed relative to the optoelectronic device 1 such that the radiation from the external radiation source 5 strikes at least onto a component 4 of the optoelectronic device 1. In other words, at least a component 4 of the optoelectronic device 1 is disposed in the beam path of the external radiation source 5. For example, the external radiation source 5 is an ultraviolet lamp or an infrared lamp.

[0073] Furthermore, the optoelectronic device 1 has an external detection element 6, which is configured to detect secondary radiation emitted by the component 4 after irradiation by the external radiation source 5 with radiation in the second wavelength range. The external detection element 6 is configured relative to the optoelectronic device 1 such that the emitted secondary radiation strikes or is guided onto the external detection element 6.

[0074] In the method for identifying optoelectronic device 1, radiation in the second wavelength range is absorbed by the optically active material in component 4 and converted into radiation in the visible wavelength range. This radiation is then emitted as secondary radiation by optoelectronic device 1 and can be detected. Based on the characteristic emission band of the optically active material, it can be definitively determined that the optically active material is present in optoelectronic device 1. Therefore, optoelectronic devices without optically active materials can be distinguished from optoelectronic devices 1 that have optically active materials.

[0075] Figure 5 The optically active material CeMgAl is shown. 11 O 19 The absorption spectrum (dashed line) and emission spectrum (solid line) of Tb are shown. The relationship between relative energy ΔE (as a percentage) and wavelength λ (in nm) is plotted. Optically active material CeMgAl 11 O 19 Tb exhibits a dominant absorption band below 350 nm and can be excited particularly effectively using wavelengths below 300 nm. In particular, significant excitation is not possible using light around 450 nm. Optically active material CeMgAl 11 O 19 The emission spectrum of Tb shows characteristic lines in the green spectral range.

[0076] Figure 6A This demonstrates the optically active materials CeMgAl with different proportions in a converter-silicone mixture after external excitation with 280 nm ultraviolet radiation in an integrating sphere (Ulbrichtkugel). 11 O 19 Emission spectrum of optoelectronic device 1 with Tb. The relationship between intensity I in arbitrary units (au) and wavelength λ in nm is plotted. Emission spectra of optoelectronic devices without active materials (0% CAT) and pure CeMgAl are also shown. 11 O 19 The emission spectrum of Tb(CAT) is shown as a comparative example. Figure 6B The differential spectrum of optoelectronic device 1 with optically active material is shown, wherein the comparative spectrum of optoelectronic device without optically active material is subtracted.

[0077] exist Figure 6A and 6B In the spectrum of optoelectronic device 1 with 0.25% CAT and 1% CAT after external excitation, the optically active material CeMgAl can be clearly seen. 11 O 19 The characteristic emission band of Tb. A residual signal can also be observed upon close examination in the spectrum of optoelectronic device 1 with 0.05% CAT.

[0078] Figure 7A The following diagrams are shown for the wavelength ranges from 510 nm to 530 nm and from 530 nm to 560 nm. Figure 6B The calculated area under the emission curve was plotted. The area under curve A in arbitrary units (au) and the area of ​​the optically active material CeMgAl in weight percentage (wt%) were plotted. 11 O 19 The relationship with Tb concentration. Under no circumstances is emission expected in the wavelength range of 510 nm to 530 nm. Therefore, the area under the emission curve is close to zero. Optically active materials CeMgAl exist in the wavelength range of 530-560 nm. 11 O 19 :Tb's strong emission band. In Figure 7A It can be clearly seen that within this wavelength range, the area under the emission curve increases with the increase of the concentration of the optically active material. Figure 7B Showing from Figure 7A Part of it, in which it can be clearly seen: in the optically active material CeMgAl 11 O 19 A residual signal was already observable when the concentration of Tb was 0.05% by weight.

[0079] Figure 8 The CIE color diagram shows the optically active materials CeMgAl with different proportions in the converter-silicone mixture, emitting a wavelength of 450 nm. 11 O 19 The color coordinates of the optoelectronic device 1 with semiconductor chip 2 of Tb and the color coordinates of a comparative example without optically active material (0% CAT) are shown. Within normal manufacturing tolerances, the direct effect of the concentration of optically active material on the color coordinates cannot be determined. Therefore, the optically active material (especially due to its low concentration in the potting mix) has only a very small effect on scattering in the optoelectronic device. Furthermore, slight deviations in the color coordinates may also be caused by the manual dispensing process and variations in potting mix height within normal manufacturing tolerances.

[0080] Figure 9 This study illustrates the optically active material CeMgAl with different proportions in a converter-silicone mixture, emitting a 450 nm wavelength. 11 O 19 The relative brightness of the optoelectronic device 1 on semiconductor chip 2 (Tb) is plotted. Brightness B is shown as a percentage, and the relative brightness of the optically active material CeMgAl is shown as a weight percentage (wt%). 11 O 19The relationship between Tb concentration and its content is independent of the proportion of optically active materials in optoelectronic devices, and the brightness loss is less than one percentage point.

[0081] Figure 10 This study illustrates the optically active material CeMgAl with different proportions in a converter-silicone mixture, emitting a 450 nm wavelength. 11 O 19 The color rendering index (CRI) and R9 values ​​of the optoelectronic device 1 based on the semiconductor chip 2 of Tb are plotted. The reduction amount L in arbitrary units (au) and the optically active material CeMgAl in weight percentage (wt%) are also plotted. 11 O 19 The relationship between Tb concentration and the actual concentration. For the optically active material concentrations shown, there is almost no effect on the color rendering index of optoelectronic devices. The effect on the R9 value is also minimal.

[0082] It should be noted that for typical white conversion LEDs, the precise values ​​of CRI, and especially R9, fluctuate slightly depending on the precise color coordinates. The fluctuations in CRI and R9 observed in the experiments are within the expected and typical range.

[0083] Figure 11 The study demonstrates an optically active material CeMgAl with an emission wavelength of 450 nm and a converter-silicone mixture comprising 0.004 wt% or 1 wt% of the material. 11 O 19 The emission spectrum of the optoelectronic device 1 using the semiconductor chip 2 (Tb) is shown. The emission spectrum reveals the primary radiation of the semiconductor chip with a 450 nm band and the secondary radiation of the conversion material in the visible wavelength range. In the spectrum, the differences between the different proportions of the optically active material are essentially undetectable. Therefore, the optically active material does not affect the emission spectrum of the optoelectronic device during operation.

[0084] Figures 12A to 12C An emission spectrum is shown according to one embodiment of a method for identifying optoelectronic devices. Figure 12A The reference spectrum of the empty scaffold (leere Halterung) after excitation with 280 nm is shown. Figure 12B This demonstrates the optically active material CeMgAl on a scaffold (Halterung) after external excitation at 280 nm. 11 O 19 :Tb optoelectronic device 1 data spectrum, Figure 12C The difference spectrum obtained by subtracting the reference spectrum from the data spectrum is shown. Figure 12C The optical material CeMgAl can be clearly seen in the differential spectrum. 11 O 19The characteristic emission band of the line spectrum of Tb (simultaneously with) Figure 5 (Comparison).

[0085] Figure 13 The optically active material CeMgAl is shown. 11 O 19 :Tb(CAT), BaMgAl 10 O 17 The reflection curves of Eu(BAM) and Y₂O₃:Eu(YOE) are shown. It can be clearly seen that the optically active material has a wavelength-dependent reflectance or diffuse reflectance R(λ) well over 95% across the entire wavelength range of 450 nm to 700 nm. BaMgAl 10 O 17 Eu exhibits a reflectivity of less than 70% for wavelengths below 410 nm, CeMgAl 11 O 19 Tb exhibits less than 70% reflectivity for wavelengths below 320 nm, and Y2O3:Eu exhibits less than 70% reflectivity for wavelengths below 270 nm.

[0086] Figure 14 The optically active material CeMgAl is shown. 11 O 19 :Tb(CAT), BaMgAl 10 O 17 The relative Kubelka-Monk function at 450 nm is normalized for the values ​​of Eu(BAM) and Y2O3:Eu(YOE) and the luminescent materials YAG:Ce, LuAGaG:Ce, QL1, QL2, and CASN. These materials are commonly used in white-emitting optoelectronic devices with blue-emitting semiconductor chips. YAG:Ce and LuAGaG:Ce here represent Y3A with blue-green to orange-yellow emission. l5 O 12 :Ce or Lu3(Al,Ga)5O 12 Ce-type luminescent materials. Both of these have the more common molecular formula (Y,Gd,Tb,Lu)3(Al,Ga)5O 12 The :Ce garnet luminescent materials are typical representatives of the material family. QL1 and QL2 represent two representatives of the material family Sr(Sr,Ca)Si2Al2N6:Eu with orange-red to deep red emission. CASN represents the material family (Sr,Ca)AlSiN3:Eu with orange-red to deep red emission.

[0087] The relative Kuberca-Monk functions of the luminescent materials YAG:Ce, LuAGaG:Ce, QL1, QL2, and CASN did not show an increase for wavelengths below 450 nm, while the optically active materials CAT, BAM, and YOE had relative Kuberca-Monk functions greater than 1 for wavelengths below 450 nm. The optically active material BAM showed a relative Kuberca-Monk function greater than 100 below 415 nm. The optically active material YOE showed a relative Kuberca-Monk function greater than 1000 below 365 nm, and the optically active material CAT showed a relative Kuberca-Monk function greater than 1000 below 300 nm. Therefore, the absorption of these optically active materials is stronger in these wavelength ranges than at 450 nm.

[0088] According to other embodiments, the features and embodiments described in conjunction with the accompanying drawings can be combined with each other, even if not all combinations are explicitly described. Furthermore, the embodiments described in conjunction with the accompanying drawings can alternatively or additionally have other features as described in the overview section.

[0089] The present invention is not limited to the embodiments described herein. Rather, the invention includes any new features and any combination of features, particularly any combination of features in the claims, even if the feature or combination itself is not expressly stated in the claims or embodiments.

[0090] This patent application claims priority to German patent applications DE 10 2020 123 707.3 and DE 10 2020 126 112.8, the disclosure of which is incorporated herein by reference.

[0091] List of reference numerals

[0092] 1 Optoelectronic devices

[0093] 2 Semiconductor chips

[0094] 3 Radiation exit surface

[0095] 4 components

[0096] 5. External radiation sources

[0097] 6 External detection elements

Claims

1. An optoelectronic device (1), comprising - A semiconductor chip (2), which is configured to emit primary radiation having a first wavelength range during operation of the optoelectronic device (1), - Component (4), which includes optically active materials. in - The component (4) is at least partially disposed in the beam path of the semiconductor chip (2), The optically active material is not configured to be excited by primary radiation having a first wavelength range, and The proportion of the optically active material in the component is from 0.004% to 1% by weight, including boundary values. The optoelectronic device (1) does not contain a semiconductor chip or optically active element configured to excite the optically active material, and The optically active material is configured to absorb radiation in a second wavelength range from outside the optoelectronic device and convert it into secondary radiation.

2. The optoelectronic device (1) according to claim 1. The semiconductor chip (2) therein emits primary radiation in the visible wavelength range.

3. The optoelectronic device (1) according to claim 1 or 2. The component (4) includes at least one light-emitting material configured to convert at least part of the radiation from the semiconductor chip (2) into secondary radiation.

4. The optoelectronic device (1) according to claim 1 or 2. The optoelectronic device (1) therein emits radiation in the visible wavelength range during operation.

5. The optoelectronic device (1) according to claim 1 or 2. The component (4) therein includes, or is an optical element, potting compound, conversion layer or passivation layer of the semiconductor chip (2).

6. The optoelectronic device (1) according to claim 1 or 2. The optically active material described therein does not absorb radiation in the visible spectrum.

7. The optoelectronic device (1) according to claim 1 or 2. The optically active material is transparent to radiation emitted by the optoelectronic device (1) during operation.

8. The optoelectronic device (1) according to claim 1 or 2. The optically active material therein does not affect the optical properties of the optoelectronic device (1).

9. The optoelectronic device (1) according to claim 1, wherein the second wavelength range is shorter than the first wavelength range, and wherein the optically active material converts radiation of the second wavelength range into radiation of a longer wavelength.

10. The optoelectronic device (1) according to claim 1. The second wavelength range is longer than the first wavelength range, and the optically active material converts radiation in the second wavelength range into radiation with a shorter wavelength.

11. The optoelectronic device (1) according to claim 1 or 2. The optically active material described therein has a re-identifiable emission spectrum.

12. The optoelectronic device (1) according to claim 1 or 2. The optically active material includes CeMgAl 11 O 19 :Tb、BaMgAl 10 O 17 Eu and / or Y₂O₃:Eu or CeMgAl 11 O 19 :Tb、BaMgAl 10 O 17 It consists of Eu and / or Y2O3:Eu.

13. A method for identifying optoelectronic devices (1), comprising: - Provide an optoelectronic device (1) according to any one of claims 1 to 12. - Irradiate the optoelectronic device from the outside with electromagnetic radiation in the second wavelength range (1). -Detect secondary radiation generated by converting radiation in the second wavelength range through the optically active material.

14. The method according to claim 13, The second wavelength range is shorter than the first wavelength range.

15. The method according to claim 13, The second wavelength range is longer than the first wavelength range.

16. The method according to any one of claims 13 to 15, The optoelectronic device (1) can be identified based on the secondary radiation.

17. The method according to any one of claims 13 to 15, The optically active material converts radiation in the second wavelength range into radiation in the visible wavelength range.

18. An optoelectronic device (1), comprising - Semiconductor chip (2), which is configured to emit primary radiation having a first wavelength range during operation of the optoelectronic device (1); - Component (4), which includes optically active materials. in - The component (4) is at least partially disposed in the beam path of the semiconductor chip (2), The optically active material is not configured to be excited by primary radiation having a first wavelength range, and -The optoelectronic device (1) does not contain a semiconductor chip or optically active element configured to excite the optically active material.

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