Semiconductor component having a radiation conversion element and method for producing a radiation conversion element

Abstract

A semiconductor component (1) is provided, comprising a semiconductor chip (2) and a radiation conversion element (3), the radiation conversion element being arranged on the semiconductor chip, wherein the semiconductor chip has an active region (20) designed to generate primary radiation (5) having a peak wavelength; the radiation conversion element has a quantum structure (30), the peak wavelength of the primary radiation being in the infrared spectral range; and the quantum structure converting the primary radiation at least partially into secondary radiation (6), wherein the emission wavelength of the emission maximum of the secondary radiation is greater than the peak wavelength. In addition, a method for producing the radiation conversion element is provided.

Description

Technical Field

[0001] The present application relates to a semiconductor component having a radiation conversion element and a method for producing a radiation conversion element. Background Art

[0002] Light-emitting diodes emitting in the infrared spectral range have emission wavelengths above 1000 nm and can be produced on GaP substrates. However, these substrates are very expensive and only available in limited quantities, and known emitters also exhibit relatively large lateral emission, which makes optical imaging difficult. Summary of the invention

[0003] One object is to achieve efficient radiation generation in the infrared spectral range.

[0004] This object is achieved in particular by a semiconductor component according to one embodiment of the invention or by a method for producing a radiation conversion element according to one embodiment of the invention. Further configurations and expedients are the subject matter of exemplary embodiments of the invention.

[0005] According to at least one embodiment of the semiconductor component, the semiconductor component comprises a semiconductor chip. The semiconductor chip comprises in particular an active region which is designed to generate primary radiation having a peak wavelength. By applying a voltage to the semiconductor chip, charge carriers can be caused to pass from opposite sides into the active region during operation of the semiconductor component and recombine there to emit radiation.

[0006] According to at least one embodiment of the semiconductor component, the semiconductor component comprises a radiation conversion element. The radiation conversion element is in particular arranged, for example fixed, on the semiconductor chip.

[0007] According to at least one embodiment of the semiconductor device, the peak wavelength of the primary radiation lies in the infrared spectral range, for example, the peak wavelength lies between 900 nm and 1100 nm, inclusive, for example, the peak wavelength lies between 920 nm and 1080 nm, inclusive.

[0008] In accordance with at least one embodiment of the semiconductor component, the radiation conversion element has a quantum structure.

[0009] In the context of the present application, the term "quantum structure" includes in particular structures in which charge carriers can undergo a quantization of their energy states by confinement. In particular, the term "quantum structure" does not include any information about the dimensionality of the quantization. The term thus includes in particular quantum wells, quantum wires and quantum dots and any combinations of these structures.

[0010] For example, the quantum structure has a plurality of quantum layers, between which barrier layers are arranged. For example, the quantum layers and the barrier layers form a multi-quantum well (MQW) structure. The radiation conversion element, for example, has a substrate that is transparent to the primary radiation. The substrate is used in particular to mechanically stabilize the quantum structure. For example, the thickness of the substrate is at least twice, or at least five times, the thickness of the quantum structure. The substrate is, for example, a growth substrate for the quantum structure, for example, epitaxial deposition. Alternatively, the substrate may also be different from the growth substrate for the quantum structure. In addition, the radiation conversion element may also not have a substrate.

[0011] According to at least one embodiment of the semiconductor device, the quantum structure converts primary radiation at least partially into secondary radiation, wherein the emission wavelength of the emission maximum of the secondary radiation is greater than the peak wavelength. The emission maximum is, for example, a global maximum of the secondary radiation or a local maximum of the secondary radiation.

[0012] The radiation conversion element can generate radiation in a wavelength range that is not easily achievable with the material system for the active region of the semiconductor chip, for example, at least one emission maximum of the secondary radiation between 1000 nm and 1700 nm inclusive.

[0013] In at least one embodiment of the semiconductor device, the semiconductor device comprises a semiconductor chip and a radiation conversion element, wherein the radiation conversion element is arranged on the semiconductor chip. The semiconductor chip has an active region designed to generate primary radiation with a peak wavelength. The radiation conversion element has a quantum structure. The peak wavelength of the primary radiation is in the infrared spectral range. The quantum structure converts the primary radiation at least partially into secondary radiation, wherein the emission wavelength of the emission maximum of the secondary radiation is greater than the peak wavelength.

[0014] In accordance with at least one embodiment of the semiconductor component, the quantum structure comprises a plurality of quantum layers which are separated from one another by barrier layers, wherein the barrier layers have a band gap which is greater than the energy of the radiation having a peak wavelength.

[0015] In other words, the energy of the radiation having the peak wavelength is insufficient to excite charge carriers in the barrier layer from the valence band to the conduction band. Radiation absorption of the primary radiation in the radiation conversion element therefore takes place substantially directly within the quantum layer.

[0016] According to at least one embodiment of the semiconductor device, the quantum structure has at least two quantum layers, which differ from each other in their band gaps. In other words, the emission spectrum of the quantum structure has at least two emission bands, whose emission maxima are different from each other. For example, the spectral spacing between the two emission maxima of the secondary radiation is greater than the sum of the half-value widths of half of the emission maxima. The emission maxima are clearly distinguished in the emission spectrum. Alternatively, the spectral spacing between adjacent maxima can be so small that the superposition of the emission bands generally causes a broadened emission spectrum.

[0017] According to at least one embodiment of the semiconductor device, the quantum structure has a lattice constant of InP. Therefore, the semiconductor material for the quantum structure can be deposited epitaxially on a growth substrate having InP, for example by means of MBE or MOVPE. The material can be lattice-matched or tensioned, as long as the tensioning forces do not cause cracks in the crystal.

[0018] According to at least one embodiment of the semiconductor device, the quantum structure comprises at least one material from the following material system: Ga x In 1-x As y P 1-y 、In x Ga 1-x As y Sb 1-y 、In x Ga 1-x As、In x Ga 1-x P y Sb 1-y 、In x Al 1-x P y Sb 1-y , wherein x and y are each selected such that the lattice constant of the material corresponds to the lattice constant of InP. In this case, x≤1 and y≤1 apply in each case. In particular, direct band gaps can be achieved with the aid of the semiconductor material, so that efficient light absorption and emission are possible.

[0019] The lattice constant of the material corresponds to that of InP, meaning that the intrinsic lattice constant of the material is equal to that of InP or deviates at least only so small that the material grows tensionally onto InP without relaxation.

[0020] For example, the intrinsic lattice constant of the material used for the quantum structure differs from the lattice constant of InP by at most 2%, in particular by at most 1%.

[0021] Emission wavelengths between 1000 nm and 1700 nm inclusive can be reliably achieved with the aid of these materials.

[0022] According to at least one embodiment of the semiconductor device, in a top view of the semiconductor device, the radiation conversion element covers the active area of ​​the semiconductor chip by at least 90%. In particular, the radiation conversion element can also completely cover the active area. As a result, radiation emitted perpendicularly to the main extension plane of the active area cannot or can only be emitted in a relatively small proportion from the semiconductor device without previously passing through the radiation conversion element. This design is particularly suitable for semiconductor devices in which primary radiation in the emission spectrum of the semiconductor device is undesirable or at least not required.

[0023] According to at least one embodiment of the semiconductor device, in a top view of the semiconductor device, the radiation conversion element covers the active area of ​​the semiconductor chip by up to 80%. In this case, a major part of the primary radiation also emerges from the semiconductor device. As a result, the spectral width of the emission spectrum is increased overall. Semiconductor devices in which the primary radiation is also included in the total spectrum are particularly suitable for applications in which broadband emission is desired, for example for biosensor applications.

[0024] According to at least one embodiment of the semiconductor component, the radiation conversion element has a thickness of at most 200 μm. The thickness relates to the extent perpendicular to the main extension plane of the active region. The thinner the radiation conversion element is, the less radiation is emitted laterally from the radiation conversion element during operation of the semiconductor component. The radiation emitted in total can be shaped more easily by optical elements arranged downstream of the semiconductor component.

[0025] In accordance with at least one embodiment of the semiconductor component, the semiconductor chip comprises a carrier, wherein a mirror layer, in particular a metallic mirror layer, is arranged between the active region and the carrier.

[0026] In particular, the carrier is different from the growth substrate for the active region of the semiconductor chip. Such semiconductor chips are also referred to as thin-film semiconductor chips. In such thin-film semiconductor chips, lateral radiation is reduced in favor of increased radiation through the radiation exit surface of the semiconductor chip opposite the mirror layer.

[0027] In particular, thin-film semiconductor chips in combination with the described radiation conversion element are suitable for reducing lateral radiation of the semiconductor component and improving the optical imageability of the emitted radiation. Furthermore, the proportion of primary radiation that is emitted laterally from the semiconductor chip and thus does not impinge on the radiation conversion element can be reduced. As a result, the proportion of primary radiation in the emission spectrum can be increased, in particular at relatively large emission angles.

[0028] Furthermore, a method for producing a plurality of radiation conversion elements is specified.

[0029] In accordance with at least one embodiment of the method, the semiconductor layer sequence having the quantum structure is deposited on the substrate, for example by means of MBE or MOVPE.

[0030] The quantum structure is deposited, for example, as a single-crystalline layer in a lattice-matched manner on a substrate having InP. In particular, at least one deposition surface of the substrate is formed by InP. This makes it possible to achieve a high layer quality with optimal absorption and emission efficiencies particularly reliably.

[0031] According to at least one embodiment of the method, the semiconductor layer sequence is singulated into a plurality of radiation conversion elements. Thus, a plurality of radiation conversion elements can be produced simultaneously in a wafer assembly, wherein the radiation conversion elements are produced during the singulation of the assembly.

[0032] According to at least one embodiment of the method, the substrate is at least partially removed from the quantum structure, in particular before singulation. The substrate is therefore no longer present in the finished radiation conversion element or is only partially present, in particular with a reduced thickness.

[0033] According to at least one embodiment of the method, in order to remove the substrate at least partially from the quantum structure, a sacrificial layer is removed. The sacrificial layer is located between the quantum structure and the back side of the substrate facing away from the quantum structure, for example, between the quantum structure and the deposition surface of the substrate. The sacrificial layer is, for example, a layer that can be easily and reliably removed by chemical methods.

[0034] According to at least one embodiment of the method, a separation seed is introduced into the substrate and a portion of the substrate is separated along the separation seed. The separation seed can be introduced, for example, by ion implantation. The separation can be performed, for example, by means of heating the substrate.

[0035] According to at least one embodiment of the method, at least part of the substrate is further used in a further production cycle of the method for depositing a semiconductor layer sequence having a quantum structure. The production costs for the radiation conversion element can thereby be further reduced.

[0036] According to at least one embodiment of the method, the substrate is thinned before the division. This is done, for example, by mechanical methods, such as grinding, polishing or lapping. The more the substrate is thinned, the smaller the lateral emission from the radiation conversion element can be. During the deposition of the semiconductor layer sequence for the quantum structure, the substrate can have a greater thickness, so that the substrate has sufficient mechanical stability even at relatively high temperatures for the deposition of the semiconductor layer sequence.

[0037] The method described is particularly suitable for the production of the radiation conversion element described above. Therefore, features described in conjunction with the method can also be used for the radiation conversion element and vice versa.

[0038] The following effects can be achieved, in particular, by means of the described semiconductor component or the described method.

[0039] For the active region, a material system can be used by which primary radiation can be efficiently generated, in particular by electrical excitation. Thus, only relatively little technical effort is incurred, in particular compared to creating a new material system for the semiconductor chip, to generate radiation with the desired longer wavelength.

[0040] The manufacturing process for producing the semiconductor chips may be similar to established technologies for light sources that generate radiation, which generates radiation that appears white to the human eye or other radiation in the visible spectral range.

[0041] By means of a radiation conversion element with a quantum structure, the spectral characteristics of the radiation of the semiconductor component can be particularly easily and reliably adapted to predefined requirements, for example by means of a change in the layer thickness and / or band gap of the quantum layers of the quantum structure. In contrast, the emission spectrum of luminescent materials emitting in the infrared spectral range remains virtually unchanged. The emission wavelength of the secondary radiation can be adjusted over the entire spectral range of 1000 nm to 1800 nm.

[0042] Furthermore, multi-band emission and / or broad-spectrum emission can be easily achieved by modifying the quantum layers of the emission-converting element, if so desired.

[0043] Excitation can be performed by means of radiation of relatively long wavelength. Due to the small spectral spacing between the primary radiation and the secondary radiation, a high efficiency of the semiconductor component is achieved with a simultaneously small Stokes shift. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Further embodiments and suitable methods will be apparent from the following description of the exemplary embodiments in conjunction with the accompanying drawings.

[0045] The accompanying drawings show:

[0046] Figure 1A , 1B , 1C, 1D and 1E are schematic cross-sectional views of embodiments for semiconductor devices ( Figure 1A ) or schematic top view ( Figures 1B to 1E );

[0047] Figure 2A and 2B Schematic diagrams respectively showing embodiments of a band structure of a radiation conversion element;

[0048] Figure 3A , 3B 3C and 3D respectively show embodiments of emission spectra for semiconductor devices;

[0049] Figure 4 A diagram showing possible achievable emission wavelengths for different semiconductor material systems, where the band gap EG (left scale) and the associated radiation wavelength λ (right scale) are shown as a function of the lattice constant d;

[0050] Figure 5A Examples of measured data showing the intensity in arbitrary units in relation to the wavelength of different light emitting diodes;

[0051] Figure 5B Examples of measured data of the intensity as a function of the wavelength of a light-emitting diode at two different currents are shown in arbitrary units in a linear scale (on the left) and in a corresponding logarithmic scale (on the right).

[0052] Figure 5C shows an example of photoelectric intensity measurements in arbitrary units at two epitaxial substrates with different quantum structures as a function of wavelength;

[0053] Figures 6A to 6C , 7A to 7C, 8A to 8D and 9A to 9D each show an exemplary embodiment of a method for producing a radiation conversion element using schematically illustrated intermediate steps.

[0054] Elements that are identical, of the same type or have the same function are provided with the same reference symbols in the figures.

[0055] The figures are each schematic representations and are therefore not necessarily true to scale. Rather, relatively small elements and in particular layer thicknesses may be illustrated with an exaggerated size for the sake of clarity. DETAILED DESCRIPTION

[0056] exist Figure 1A Along the Figure 1B The sectional view along the line AA' shown in FIG. 1 shows an embodiment of a semiconductor device 1. The semiconductor device 1 has a semiconductor chip 2 having an active region 20 designed to generate primary radiation. The active region is located between a first semiconductor layer 21 and a second semiconductor layer 22 of the semiconductor chip. For example, the first semiconductor layer 21 is n-type and the second semiconductor layer 22 is p-type, or vice versa. By applying an external voltage between a contact 45 and a further contact 46 of the semiconductor chip, charge carriers can reach the active region 20 via the first semiconductor layer 21 and the second semiconductor layer 22 from opposite sides and recombine there to emit primary radiation.

[0057] A radiation conversion element 3 is arranged on the semiconductor chip 2. The radiation conversion element 3 is fixed to the semiconductor chip 2 by means of an adhesive layer 4. The adhesive layer contains silicon or epoxy, for example. The adhesive layer 4 is expediently transparent to the radiation generated in the active region 20.

[0058] The radiation conversion element 3 has a quantum structure 30. For the sake of simplicity, Figure 1A2 and 3. In FIG. 2 , two quantum layers 31 and two barrier layers 32 are shown. However, the number of quantum layers can vary within a wide range, for example between one quantum layer and 50 quantum layers (inclusive of the limit values).

[0059] The quantum structure 30 is arranged on a substrate 35 of the radiation conversion element 3. For example, the substrate is a growth substrate, in particular an epitaxial deposition, for the quantum structure 30. However, the growth substrate for the semiconductor layers of the quantum structure 30 does not have to be completely contained in the semiconductor component 1, but can be completely or partially removed during the production of the radiation conversion element 3.

[0060] The peak wavelength of the primary radiation lies, for example, in the infrared spectral range. For example, the peak wavelength is between 920 nm and 1070 nm, inclusive, in particular between 940 nm and 1000 nm, inclusive.

[0061] For example, the active region 20 of the semiconductor chip 2 is based on the material system In x Ga y Al 1-x-y As z P 1-z The parameters x, y and z of the material composition are selected in particular such that the material can be deposited in a monocrystalline manner on a GaAs substrate as a growth substrate.

[0062] In the exemplary embodiment shown, the semiconductor chip 2 is designed as a thin-film semiconductor chip, wherein a growth substrate for the semiconductor layer sequence having the active region 20 is no longer present in the finished semiconductor chip. The semiconductor layer sequence having the active region 20 is fixed to a carrier 29 by means of a connecting layer 26. The carrier 29 itself does not have to meet the high requirements for the crystal purity of the growth substrate. A mirror layer 25, in particular a metal, is also arranged between the active region 20 and the carrier 29, so that the radiation generated in the active region 20 and emitted in the direction of the carrier 29 is reflected and emerges at a radiation exit surface 200 of the semiconductor chip 2 opposite the carrier 29.

[0063] The primary radiation generated in the active region 20 is at least partially converted into secondary radiation in the quantum structure 30 of the radiation conversion element 3 .

[0064] The material composition of the barrier layer is preferably selected such that it has a band gap that is greater than the energy of the radiation having the peak wavelength of the primary radiation. Figure 2A According to the valence band E of quantum structure 30 V and conduction band E C The primary radiation 5 indicated by the arrow is not absorbed in the barrier layer 32 but in the quantum layer 31. The excitation 51 thus generated is illustrated by the arrow.

[0065] Subsequently, secondary radiation 6 with a longer wavelength, indicated by the arrow, can be emitted. This emission takes place, for example, from the ground state of the quantum well formed by the quantum layer. Thus, direct optical excitation of the quantum layer 31 and thus particularly efficient radiation conversion take place.

[0066] exist Figure 2A In the exemplary embodiment shown in , the band gaps of the quantum layers 31 do not differ from one another or differ only slightly from one another. This results in a spectrally narrowband emission spectrum.

[0067] Different from this, Figure 2B , an exemplary embodiment is shown in which at least two quantum layers 31 differ from one another in terms of their band gaps. By selecting material parameters for the quantum layers 31 of the quantum structure 30 , the emission spectrum of the semiconductor component can be easily and reliably adapted to a predetermined emission characteristic.

[0068] exist Figures 3A to 3D , various embodiments of the emission spectrum of a semiconductor component are shown, wherein the intensity in arbitrary units is shown as a function of the wavelength λ. Line 901 shows the primary radiation and line 902 shows the secondary radiation. Figure 3A In the embodiment shown in , the secondary radiation has exactly one emission maximum, which is a global maximum.

[0069] However, since the quantum layers are different from each other, as in Figure 3B As shown in , it is also possible to achieve an emission spectrum in which the secondary radiation has two or more emission bands spaced apart from one another, which have emission maxima 9021 or 9022 that are different from one another. For example, the spectral spacing between two emission maxima 9021, 9022 can be greater than the sum of the half widths at half maximum (full width at half maximum, HWHM) of the emission bands, so that the emission spectrum has emission maxima that are significantly different from one another in the secondary radiation.

[0070] Alternatively, the spacing between adjacent emission maxima can also be smaller, such as in Figure 3C In this case, emission maxima 9021, 9022 and 9023 can be superimposed to form a common spectrally broadened emission peak, so that the semiconductor component 1 is spectrally characterized by a particularly broad emission. Thus, by targeted modification of the quantum layers, the emission spectrum of the secondary radiation can be broadened.

[0071] The spectrum of the primary radiation 901 can also be, as in Figure 3D The diagram illustrates that there is more than one emission maximum, for example, emission maximum 9011 and another emission maximum 9012.

[0072] Particularly suitable for the quantum structure 30 are materials that can be epitaxially deposited onto InP.

[0073] For example, the quantum structure has at least one material selected from the following material systems: Ga x In 1-x As y P 1-y 、In x Ga 1-x As y Sb 1-y 、In x Ga 1-x As、In x Ga 1-x P y Sb 1-y 、In x Al 1-x P y Sb 1-y , wherein x and y are each selected such that the lattice constant of the material corresponds to or is at least close to the lattice constant of InP. A peak wavelength of at least 920 nm, for example at least 930 nm or at least 940 nm, is particularly suitable for the primary radiation, so that the primary radiation is not absorbed by the InP substrate 35 of the radiation conversion element 3 and the barrier layer 32 of the same material.

[0074] The proportion of the primary radiation in the emission spectrum of the semiconductor component 1 can also be adjusted by means of the degree of coverage of the radiation exit area 200 of the semiconductor chip 2 with the radiation conversion element 3. Figures 1B to 1E Graphic illustration. Figure 1B In the embodiment shown in FIG. 1 , the semiconductor chip 2 has a contact 45 on the front side in the corner region of the semiconductor chip 2 . The radiation conversion element 3 has a recess 39 so that the contact 45 is accessible for external electrical contacting of the semiconductor device 1 , for example by means of a wire bond connection. The active region 20 is completely or at least substantially completely covered, for example with a coverage of at least 90°. Therefore, the primary radiation emerging through the radiation exit surface 200 must pass through the radiation conversion element 3 before it emerges at the front side 10 of the semiconductor device 1 .

[0075] In contrast, the radiation conversion element 3 Figure 1C In the exemplary embodiment shown in FIG. 1 , the active region 20 of the semiconductor chip 2 is only partially covered, for example with a coverage of at most 80% or at most 50%. As a result, a major proportion of the primary radiation is emitted laterally from the radiation conversion element 3 at the front side 10 of the semiconductor component 1. This is particularly advantageous, in particular, if the primary radiation is desired in the emission spectrum of the semiconductor component 1.

[0076] exist Figure 1D and 1EEmbodiments and methods in Figure 1B and 1C The embodiment of FIG. 2 differs in that the contact 45 is no longer in the corner region but extends along the side surface 27 of the semiconductor chip 2 . Figure 1D In the embodiment shown in FIG. 1 , the radiation conversion element 3 , such as in combination with Figure 1C As described, the active region 20 of the semiconductor chip 2 is only partially covered, so that a major proportion of the radiation exit area of ​​the semiconductor chip 2 remains free of radiation conversion elements. Figure 1E In the exemplary embodiment shown in , the radiation exit area is completely or substantially completely covered by the radiation conversion element 3. For this purpose, the radiation conversion element can have a simple, for example rectangular, shape.

[0077] exist Figure 4 9 illustrates which emission wavelengths can be achieved with the aid of a specific material system. Lines 905 and 906 illustrate the lattice constants of gallium arsenide or indium phosphide. It can be seen from this that emission in the spectral range between 1000 nm and 1700 nm (inclusive of the limit values) cannot be easily achieved with the aid of the lattice constants of gallium arsenide. The material system of the nitride semiconductor 990 with the corner points InN, GaN and AlN does not grow in the zincite structure, but in the wurtzite structure, unlike the other material systems shown, and thus cannot be easily combined with the other material systems shown.

[0078] However, due to the lattice constant of InP, a spectral range between 1000 nm and 1700 nm inclusive can be achieved. This is illustrated graphically by the arrow 908 between the two lines 907 .

[0079] exist Figure 5A shows a measurement of the intensity of the radiation emitted by different light-emitting diodes, each of which was deposited on a GaAs substrate. Radiation with a peak wavelength between 950 nm and 1000 nm can be generated efficiently, while the intensity of the comparative samples with a peak wavelength above 1000 nm is significantly reduced. Therefore, the material system is not necessarily suitable for the direct radiation generation with a peak wavelength above 1000 nm.

[0080] exist Figure 5B The measurement of the intensity of the light-emitting diodes at two different operating currents as a function of the wavelength is shown in FIG. For these light-emitting diodes, the layer thickness is increased in some quantum layers in the active region. This results in two emission bands, which are spaced apart by approximately 15 nm. This results in a broadened emission spectrum. The described approach can also be transferred to the quantum structure of the radiation conversion element described and to other emission wavelengths, thereby enabling a broadened emission spectrum of the secondary radiation (see Figure 3C ).

[0081] exist Figure 5C , photoelectric measurements of two substrates are shown, on which two active regions are deposited respectively, which are electrically connected to each other via a tunnel junction. Curve 910 is based on a structure in which the first active region has a quantum layer for emission at 810 nm and a quantum layer for emission at 1020 nm. The second active region has a quantum layer for emission at 850 nm and a quantum layer for emission at 940 nm. The method can also be transferred to the quantum structure of the radiation conversion element described and to other emission wavelengths, thereby achieving an emission spectrum of secondary radiation with individual emission bands spaced apart from each other (see Figure 3D ).

[0082] Curve 920 is based on a modified structure in which some quantum layers of the emission bands at 810 nm and 850 nm are purposefully formed with greater layer thicknesses. This results in additional emission at slightly larger wavelengths. Thus, the spectrum has individual emission bands in which the emission peaks are partially purposefully broadened.

[0083] on the whole, Figure 5B and 5C The measurement results demonstrate the great flexibility in the design of the emission spectrum of quantum structures.

[0084] exist Figures 6A to 6C An embodiment of a method for manufacturing a radiation conversion element is described in Figure 6B , a semiconductor layer sequence 300 having a quantum structure 30 is epitaxially deposited. Singulation then takes place into a plurality of radiation conversion elements 3. The singulation is carried out, for example, mechanically, for example by sawing, chemically, for example by etching, or by means of laser separation.

[0085] Before or during singulation, cutouts for the radiation conversion elements to be produced can also be created. This makes it possible to produce radiation conversion elements in a simple manner which do not have a rectangular cross section (see Figure 1B ) The radiation conversion element 3 shown in FIG.

[0086] Otherwise, the radiation conversion element produced in this way can be designed as described in conjunction with the preceding figures and therefore not explained in detail at this point.

[0087] The singulated radiation conversion elements 3 can subsequently be placed on a semiconductor chip for the production of a semiconductor component and fixed thereto.

[0088] The dimensions of the substrate 35 for the radiation conversion element 3 are thus independent of the dimensions of the substrate on which the semiconductor chip is produced. Thus, for example, a more cost-effective 4" substrate can be used for the radiation conversion element even if the semiconductor chip is produced based on a 6" process.

[0089] exist Figures 7A to 7C The embodiment shown in Figures 6A to 6C The embodiment described differs in that the substrate 35 is deposited before the quantum structure 30 ( Fig. 7A ) is then thinned, for example by mechanical means such as grinding ( Figure 7B ) Thinning. Next, split ( Figure 7C ). As a result, the thickness of the substrate remaining in the radiation conversion element 3 can be reduced. The smaller the substrate thickness, the smaller the proportion of radiation which emerges laterally from the radiation conversion element can be.

[0090] By way of example, the radiation conversion element has a thickness of at most 200 μm after thinning.

[0091] exist Figures 8A to 8D The following method is described in detail, by means of which a radiation conversion element 3 can be produced without an initial substrate. For this purpose, a sacrificial layer 37 ( Figure 8B The sacrificial layer can then be removed, for example by selective etching, so that the quantum structure 30 and the substrate 35 are separated from each other ( Figure 8C ).

[0092] The separation of the quantum structure and the substrate is preferably performed in a split ( Fig.8D ), so that the substrate 35 can be reused in another production cycle to deposit the semiconductor layer sequence. By reusing the relatively expensive growth substrate in this way, the production costs for the radiation conversion element can be further reduced. In addition, particularly thin radiation conversion elements can be produced.

[0093] exist Figures 9A to 9D In the embodiment described in the above, the substrate 35 has a separate seed crystal 38. The separate seed crystal can be introduced into the substrate by ion implantation, for example, hydrogen ion implantation is suitable.

[0094] This has been done in the deposition of the semiconductor layer sequence for the quantum structure 30 ( Fig. 9B Alternatively, it is also conceivable to first deposit the quantum structure 30 and then form the separate seed crystal 38.

[0095] The substrate 35 may be split along the separation seed crystal 38, for example by thermal cleavage ( Fig. 9C ). This results in a separated portion 351 of the substrate.

[0096] Finally, segmentation can be performed as described in the above embodiment ( Fig.9D ).

[0097] Optionally, after preparing the surface of the substrate, such as by combining Figures 8A to 8D As described, the separated portion 351 is used again.

[0098] With the aid of the semiconductor component 1 described and the production method described, radiation in the infrared spectral range, in particular between 1000 nm and 1700 nm inclusive, can be generated in a particularly efficient manner. The emission spectrum can be easily adapted to the respective application for the semiconductor component, in particular by selecting the layer thickness and material composition of the quantum layers for the quantum structure.

[0099] For example, the semiconductor component is suitable as a light source for analytical applications, for example for water detection or humidity detection.The secondary radiation can form only the emission spectrum of the semiconductor component or be present in addition to the primary radiation.

[0100] It is also possible, in particular in conjunction with a semiconductor chip 2 designed as a thin-film semiconductor chip, to achieve a majority of the radiation emission at the front side of the semiconductor component, so that the spatial emission characteristic can be shaped in a simplified manner via optical elements arranged downstream.

[0101] Thin-film technology can be used for this purpose, in which the GaAs growth substrate is removed.

[0102] This patent application claims the priority of German patent application 10 2019 115 351.4, the disclosure content of which is incorporated herein by reference.

[0103] The invention is not restricted by the description based on the exemplary embodiments. Rather, the invention encompasses any novel feature and any combination of features, which in particular includes any combination of features in the claims, even if the feature or the combination itself is not described in detail in the claims or exemplary embodiments.

[0104] Reference numerals list

[0105] 1 Semiconductor devices

[0106] 10 Front

[0107] 2 Semiconductor Chips

[0108] 20 Active area

[0109] 200 Radiation exit surface

[0110] 21. First semiconductor layer

[0111] 22. Second semiconductor layer

[0112] 25 Mirror Layer

[0113] 26 Connection Layer

[0114] 27 Side

[0115] 29 Carrier

[0116] 3 Radiation conversion elements

[0117] 30 Quantum Structure

[0118] 300 Semiconductor layer sequence

[0119] 31 Quantum Layer

[0120] 32 Barrier layer

[0121] 35 Substrate

[0122] 351 Separation Part

[0123] 37 Sacrificial layer

[0124] 38 Separation of seed crystals

[0125] 39 blank space

[0126] 4 Adhesion layer

[0127] 45 Contact Department

[0128] 46 Other contact parts

[0129] 5 Primary Radiation

[0130] 51 Excite

[0131] 6 Secondary Radiation

[0132] 901 Curve

[0133] 9011 Maximum

[0134] 9012 Maximum

[0135] 902 Curve

[0136] 9021 Maximum

[0137] 9022 Maximum

[0138] 9023 Maximum

[0139] 905 line

[0140] 906 lines

[0141] Line 907

[0142] 908 Arrow

[0143] 910 Curve

[0144] 920 Curve

[0145] 990 Nitride Semiconductor Material System

Claims

1. A semiconductor component (1) comprising a semiconductor chip (2) and a radiation conversion element (3), the radiation conversion element being arranged on the semiconductor chip, wherein The semiconductor chip comprises an active region (20) which is designed to generate primary radiation (5) having a peak wavelength; - the radiation conversion element has a quantum structure (30); - the quantum structure has a plurality of quantum layers (31), the quantum layers being separated from each other by barrier layers (32); - the peak wavelength of the primary radiation is in the infrared spectral range; and - the quantum structure converts the primary radiation at least partially into secondary radiation (6), wherein the emission wavelength of the emission maximum of the secondary radiation is greater than the peak wavelength, wherein the quantum structure has at least two quantum layers, the at least two quantum layers differing from one another in terms of their band gaps, wherein the emission spectrum of the quantum structure has at least two emission bands, the emission maxima of the emission bands being different from each other, and The spectral spacing between adjacent emission maxima is so small that the superposition of the emission bands results in a broadened emission spectrum overall.

2. The semiconductor device according to claim 1, The barrier layer (32) has a band gap which is larger than the energy of radiation having a peak wavelength.

3. The semiconductor device according to claim 1 or 2, The quantum structure has a lattice constant of InP.

4. The semiconductor device according to claim 1 or 2, The quantum structure comprises at least one material from the following material systems: Ga x In 1-x As y P 1-y 、In x Ga 1- x As y Sb 1-y 、In x Ga 1-x As、In x Ga 1-x P y Sb 1-y 、In x Al 1-x P y Sb 1-y , where x and y are respectively selected so that the lattice constant of the material corresponds to the lattice constant of InP.

5. The semiconductor device according to claim 1 or 2, In this case, in a plan view of the semiconductor component, the radiation conversion element covers an active area of ​​the semiconductor chip by a maximum of 80%.

6. The semiconductor device according to claim 1 or 2, In this case, the radiation conversion element covers the active area of ​​the semiconductor chip to at least 90% in a plan view of the semiconductor component.

7. The semiconductor device according to claim 1 or 2, The radiation conversion element has a thickness of at most 200 μm.

8. The semiconductor device according to claim 1 or 2, The semiconductor chip comprises a carrier (29) and a mirror layer (25) is arranged between the active region and the carrier.

9. A method for producing a plurality of radiation conversion elements (3), comprising the following steps: a) depositing a semiconductor layer sequence (300) having a quantum structure (30) on a substrate (35); and b) dividing the semiconductor layer sequence into a plurality of radiation conversion elements, wherein the quantum structure has at least two quantum layers, the at least two quantum layers differing from one another in terms of their band gaps, wherein the emission spectrum of the quantum structure has at least two emission bands, the emission maxima of the emission bands being different from each other, and The spectral spacing between adjacent emission maxima is so small that the superposition of the emission bands results in a broadened emission spectrum overall.

10. The method according to claim 9, The substrate is at least partially removed from the quantum structure.

11. The method according to claim 10, The sacrificial layer (37) is removed.

12. The method according to claim 10, A separation seed crystal (38) is introduced into the substrate and a portion of the substrate is separated along the separation seed crystal.

13. The method according to any one of claims 9 to 12, Therein at least a portion of the substrate is reused in step a) in another production cycle of the method.

14. The method according to any one of claims 9 to 12, Therein, the substrate is thinned prior to step b).

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