Optoelectronic semiconductor body, optoelectronic semiconductor chip with same, and method of producing said optoelectronic semiconductor body

Abstract

An optoelectronic semiconductor body with a semiconductor layer sequence (2) based on a lll-V compound semiconductor material is specified, wherein: - the semiconductor layer sequence (2) comprises an n-doped layer (21) doped with a group VI dopant; - the semiconductor layer sequence (2) comprises an active region (20) configured to emit and / or absorb radiation; - the semiconductor layer sequence (2) comprises an interlayer (23) between the active region (20) and the n-doped semiconductor layer (21); and - the interlayer (23) comprises phosphorus (P) and at least one further group V material, preferably arsenic (As). An optoelectronic semiconductor chip (1) comprising the same is also specified. Finally, methods of producing the same are also specified.

Description

[0001] 2023PF01338 January 30, 2025 P2023,1492 WO N - 1 - Description OPTOELECTRONIC SEMICONDUCTOR BODY, OPTOELECTRONIC SEMICONDUCTOR CHIP AND METHOD OF PRODUCING A SEMICONDUCTOR BODY The present application relates to an optoelectronic semiconductor body, to an optoelectronic semiconductor chip and to a method of producing an optoelectronic semiconductor body. In optoelectronic semiconductor chips such as light-emitting diodes (LEDs) or lasers, high doping levels in the n-side of the pn-junction are preferred in order to obtain a good n- contact and / or efficient current spreading and / or minimize carrier leakage out of the active region. However, the active region of the semiconductor chips may be negatively affected if the dopants diffuse and / or segregate into the active region where they may act as unintended defects. An object is to provide a way to improve efficiency. This object is achieved, inter alia, by an optoelectronic semiconductor body, an optoelectronic semiconductor chip and a method according to the independent claims. Further configurations and developments are subject of the dependent claims. An optoelectronic semiconductor body with a semiconductor layer sequence is specified. In particular the semiconductor layer sequence is based on a III-V-compound semiconductor material. For example, the semiconductor layer sequence forming the semiconductor body is epitaxially grown. 2023PF01338 January 30, 2025 P2023,1492 WO N - 2 - For example, the semiconductor layer sequence is based onAlxInyGa1-x-yPuAsvSb1-u-vwith 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, x + y ≤1, 0 ≤ u ≤ 1, 0 ≤ v ≤ 1, u + v ≤ 1. All layers of the semiconductor layer sequence may be formed from this material. However, this material does not necessarily have to have a mathematically exact composition according to the above formula. Rather, it may comprise, for example, one or more dopants as well as additional constituents. For the sake of simplicity, however, the above formula includes only the essential constituents of the crystal lattice (Al, Ga, In, P, As, Sb), even if these may be partially replaced and / or supplemented by small amounts of other substances. According to at least one embodiment of the optoelectronic semiconductor body, the semiconductor layer sequence comprises an n-doped layer doped with a group VI dopant. The n-doped layer may be a single layer or comprise a plurality of sublayers. High carrier concentrations may be obtained by means of group VI dopants, in particular compared to a group IV dopant such as silicon. For example, a maximum carrier concentration of the n-doped layer or of a sublayer thereof is at least 5 * 1017cm-3or at least 1 * 1018cm-3. or at least 2 * 1018cm-3. According to at least one embodiment of the optoelectronic semiconductor body, the semiconductor layer sequence comprises an active region configured to emit and / or absorb radiation. For example, the active region is configured to emit or absorb radiation in the visible or near infrared spectral range. For example, a peak emission wavelength of the active region is at least 500 nm or at least 550 nm 2023PF01338 January 30, 2025 P2023,1492 WO N - 3 - and / or at most 1200 nm or at most 900 nm. In particular, the active region may be arranged between the n-doped layer and a p-doped layer, so that the active region is arranged in a pn- junction. According to at least one embodiment of the optoelectronic semiconductor body, the semiconductor layer sequence comprises an interlayer between the active region and the n-doped semiconductor layer. For example, the interlayer is part of a weakly doped region between the active region and the n-doped semiconductor layer. The semiconductor layer sequence may also comprise two or more interlayers. For example, the interlayers may be part of a superlattice. For example, the interlayers may be separated by further superlattice layers having a larger electronic bandgap than the interlayers. According to at least one embodiment of the optoelectronic semiconductor body, the interlayer comprises phosphorus and at least one further group V material. Thus, the interlayer is not a pure phosphide layer. According to at least one embodiment of the optoelectronic semiconductor body, the interlayer comprises arsenic. The interlayer may be a pure arsenide layer comprising arsenic as group V material only. Alternatively, the interlayer may comprise at least one further group V material such as phosphorous in addition to arsenic. In at least one embodiment a semiconductor body with a semiconductor layer sequence is based on a III-V-compound semiconductor material, wherein the semiconductor layer sequence comprises an n-doped layer doped with a group VI 2023PF01338 January 30, 2025 P2023,1492 WO N - 4 - dopant and an active region configured to emit and / or absorb radiation. The semiconductor layer sequence further comprises an interlayer between the active region and the n-doped semiconductor layer, the interlayer comprising phosphorus and at least one further group V material. For example, the interlayer is the only layer on the n-side of the active region that comprises the further group V material. It has been found that the interlayer comprising more than one group V material may act as a segregation barrier layer for the group VI dopant. Compared to a pure phosphide layer, the incorporation of the group VI dopant adsorbed to the wafer surface during the epitaxial growth is strongly enhanced. The enhanced segregation suppression can be leveraged to decrease defect densities in the active region and / or to optimize epitaxial designs, in particular for optoelectronic devices in the visible and the near infrared spectral range. In at least one embodiment a semiconductor body with a semiconductor layer sequence is based on a III-V-compound semiconductor material, wherein the semiconductor layer sequence comprises an n-doped layer doped with a group VI dopant wherein the n-doped layer is based on phosphide compound semiconductor material. The semiconductor layer sequence further comprises an active region configured to emit and / or absorb radiation. The semiconductor layer sequence further comprises an interlayer between the active region and the n-doped semiconductor layer, the interlayer comprising arsenic. The interlayer may be a pure arsenide semiconductor layer. In particular, the interlayer may be a pure arsenide layer free of phosphorous. Alternatively, the 2023PF01338 January 30, 2025 P2023,1492 WO N - 5 - interlayer may comprise phosphorous as further group V material in addition to arsenic. It has been found that the interlayer comprising at least arsenic as group V material may act as a segregation barrier layer for the group VI dopant of an n-doped layer based on phosphide compound semiconductor material. By means of the interlayer, the incorporation of the group VI dopant adsorbed to the wafer surface during the epitaxial growth is strongly enhanced. The enhanced segregation suppression can be leveraged to decrease defect densities in the active region and / or to optimize epitaxial designs, in particular for optoelectronic devices in the visible and the near infrared spectral range. The n-doped layer may have a comparably large electronic band gap, in particular a higher band gap than AlAs, which is the arsenide material having the highest band gap. Further, the n-doped layer that is nominally free of arsenic is superior to AlAs since AlAs and AlGaAs alloys with an aluminum content of more than 0.95 are prone to oxidation. The n-doped layer itself can be nominally free of arsenic so that a comparably high band gap can be obtained. Further high carrier concentrations can be obtained using a group VI dopant, wherein the interlayer helps to reduce the concentration of the group VI dopant in the subsequently grown active region so that the defect density in the active region may be reduced. It is noted that a III-V-compound semiconductor material comprising more than two group V materials, for instance P and As, is unusual for the n-side of optoelectronic 2023PF01338 January 30, 2025 P2023,1492 WO N - 6 - semiconductor bodies because the same band gap and lattice constant range can be covered by compound semiconductor material where the group III components such as gallium, indium, or aluminum are varied. These group III mixed crystal alloys can be controlled during production in a much easier and more precise manner than group V mixed crystal alloys since III-V-compound semiconductor materials are typically grown using very high V / III ratios so that the group III supply is limiting the growth rate. This facilitates the control of the ratios while a high group V excess supply makes it more difficult to achieve precise alloys. However, it has turned out that the segregation stopping properties of the interlayer formed from a mixed random alloy comprising more than one group V material result in superior properties of the optoelectronic semiconductor body. Further, it has been found that comparably low thicknesses of the interlayer are sufficient to suppress the segregation of the group VI dopant towards the active region. For example, the thickness of the interlayer is at least 1 nm and / or at most 300 nm or at most 200 nm. In particular, the thickness of the interlayer may be at least 2 nm and / or at most 20 nm. This helps to reduce unintended absorption of radiation in the visible spectral range in the n-side of the semiconductor layer sequence. According to at least one embodiment of the optoelectronic semiconductor body, the further group V material is arsenic. For example the interlayer comprises exactly two group V materials, namely phosphorus and arsenic. Alternatively, antimonide may be present as a further group V material or as an additional group V material in addition to phosphorus and arsenic as further group V materials. 2023PF01338 January 30, 2025 P2023,1492 WO N - 7 - It has been found that an interlayer comprising phosphorus and arsenic as group V materials may represent a highly efficient segregation barrier for the group VI dopant. According to at least one embodiment of the optoelectronic semiconductor body, at least 1% of the group V lattice sites is occupied with the further group V material, such as arsenic. In other words, the concentration of arsenic v is at least 0.01. According to at least one embodiment of the optoelectronic semiconductor body, the group V dopant is tellurium, selenium, or sulfur. The semiconductor body may also comprise more than one of these group VI dopants. By using one or more of these group VI dopants, high carrier concentrations can be obtained for the n-doped layer. In particular, tellurium has proven to be particularly suited as an n-dopant. According to at least one embodiment of the optoelectronic semiconductor body, a concentration of the group VI dopant has a local maximum in the interlayer. The concentration in the local maximum may be small compared to the concentration of the group VI dopant in the n-doped layer. In other words, the concentration of the group VI dopant in the interlayer is higher than in a material directly adjoining the interlayer on a side of the interlayer facing away from the n-doped semiconductor layer and higher than in 2023PF01338 January 30, 2025 P2023,1492 WO N - 8 - the material directly adjoining the interlayer on a side of the interlayer facing the n-doped semiconductor layer. However, such a local maximum in the interlayer does not necessarily have to occur. For example, it may be the case that a local maximum is not present, if a pure arsenide or an arsenide-phosphide-compound semiconductor layer is grown right after a Te-doped pure phosphide layer in such a way that Te supply is turned off at the same time as the growth is switched from a pure phosphide growth to a growth of an As comprising layer. This may result in a much faster decay of the Te-doping concentration compared to the decay that would occur if the growth were continued with a pure phosphide compound semiconductor material. Thus, during production of the optoelectronic semiconductor layer sequence, the group VI dopant present at the surface of the epitaxial material is efficiently incorporated into the interlayer. This helps to suppress the dopant density below an acceptable level prior to the growth of the active region where the segregated group VI dopants would act as defects. For example, the concentration of the group VI dopant in the local maximum is smaller than in the n-doped layer, for instance by at least 1% or at least 10% or by a factor of at least 5 or by a factor of at least 10. However, the concentration in the local maximum may also be equal to or even higher than in the n-doped layer. According to at least one embodiment of the semiconductor layer sequence, the semiconductor layer sequence comprises a weakly doped region between the active region and the n- conducting semiconductor layer. In this context "weakly 2023PF01338 January 30, 2025 P2023,1492 WO N - 9 - doped" in particular means that a dopant concentration is at least in regions at most 5 * 1017cm-3or at most 1 * 1017cm-3. In particular, the term “weakly doped” also includes the case that no dopant is intentionally provided during the growth of the respective semiconductor material. In other words, the weakly doped layer may also be nominally undoped. Alternatively or in addition, the group VI dopant of the n-doped layer may be present in the weakly doped region due to segregation effects, for example. For example, a minimum dopant concentration in the weakly doped region is at least by a factor of 5 or a factor of 10 lower than a maximum dopant concentration in the n-doped layer. In particular the interlayer is part of the weakly doped region. For example, the interlayer is located within the weakly doped region so that material of the weakly doped region is present on both sides of the interlayer. For example, the interlayer is the only layer of the weakly doped region that comprises arsenic. According to at least one embodiment of the optoelectronic semiconductor body, a concentration of the group VI dopant in the weakly doped region continuously decreases at least in regions in a direction from the n-doped layer towards the interlayer. This decreasing incorporation of the group VI dopant into the weakly doped region may be due to the comparably slow decay of the surface accumulation of the group VI dopant after the group VI dopant supply has been switched off. 2023PF01338 January 30, 2025 P2023,1492 WO N - 10 - According to at least one embodiment of the optoelectronic semiconductor body, the n-doped layer comprises phosphorus as group V material. For example, the phosphorus content u is at least 0.1 or at least 0.25 or at least 0.5. A large electronic band gap may be obtained by means of phosphorus, in particular compared to arsenide or antimonide compound semiconductor material. According to at least one embodiment of the optoelectronic semiconductor body, the n-doped layer is based on phosphide compound semiconductor material. Thus, the n-doped layer isbased on AlxInyGa1-x-yP. For example, the condition x + y = 1applies so that the material is free of gallium. In particular, the indium content y may be 0.49 with a toleranceof at most + / - 0.03, so that the lattice constant mismatchcompared to gallium arsenide, which may be used as a growth substrate, is sufficiently small in order to enable a critical layer thickness larger than the epitaxial stack.Alternatively, germanium may be used as a growth substrate,as germanium has has a sufficiently small enough lattice constant mismatch, similar to gallium arsenide. According to at least one embodiment of the optoelectronic semiconductor body, a lattice mismatch of the n-doped layer and of the interlayer is at most + / - 9000 ppm with respect to a growth substrate of the semiconductor layer sequence. A lattice mismatch m is defined as m = (g – g0) / g0 where g is the intrinsic, unstrained lattice constant of the epitaxial material to be grown and g0 is the lattice constant of the substrate. 2023PF01338 January 30, 2025 P2023,1492 WO N - 11 - For a quaternary material comprising two group III materials and two group V materials, formulas for lines of a constant strain may be given. If for example the material systemAlaIn1-aAs1-bPbis considered, a mismatch close to 0 ppm isobtained if the following condition is met: b = (29.2274 * (1.02049 – a)) / (a + 13.9975). It is noted that the material system AlInAsP may also be considered as an intermediate random alloy betweenAl0.51In0.49P and AlAs, wherein both materials are nearlylattice matched to gallium arsenide. Thus, the materialsystem can also be written as (Al0.51In0.49P)u(AlAs)1-uwith0 < u < 1. A mismatch close to -9000 ppm is obtained if the following condition is met: b = (29.2274 * (1.14859 – a)) / (a + 13.9975). A mismatch close to +9000 ppm is obtained if the following condition is met: b = (29.2274 * (0.892392 – a)) / (a + 13.9975). Similar conditions may be derived for other quaternary materials such as GaInAsP. According to at least one embodiment of the optoelectronic semiconductor body, the active region comprises a quantum structure with at least one active layer. In the context of the application, the term quantum structure comprises in particular any structure in which charge carriers can undergo a quantization of their energy states by confinement. In particular, the term quantum structure does 2023PF01338 January 30, 2025 P2023,1492 WO N - 12 - not imply any limitation on the dimensionality of the quantization. It thus includes, among others, quantum wells, quantum wires, quantum rods and quantum dots and any combination of these structures. Thus, the active layer may be a quantum well or a layer comprising quantum dots, for example. According to at least one embodiment of the optoelectronic semiconductor body, the active layer is based on phosphide compound semiconductor material. Thus, the active layer may be free of arsenic. This helps to obtain comparably large electronic transition energies within the active layer. According to at least one embodiment of the optoelectronic semiconductor body, wherein the active layer comprises arsenic and phosphorous as group V materials. The electronic transition energy within the active layer may be appropriately selected by means of the ratio between arsenic and phosphorous. According to at least one embodiment of the optoelectronic semiconductor body, a barrier layer of the active region is based on phosphide compound semiconductor material. A pure phosphide compound semiconductor layer free of arsenic may have a comparably large electronic bandgap. According to at least one embodiment of the optoelectronic semiconductor body, a distance between the active layer of the quantum structure closest to the n-doped layer and the n- doped layer is at least 50 nm and / or at most 1000 nm or at most 500 nm. By means of the interlayer, an unintended doping of the active region due to segregation of the group VI 2023PF01338 January 30, 2025 P2023,1492 WO N - 13 - dopant can be prevented with comparably low distances. In contrast, at least a few hundred nm of pure phosphide material such as InAlP would be required to suppress the dopant density below an acceptable level in the active region. A distance between the interlayer and the n-doped layer may be in a range from 0 nm to 600 nm, for example. A distance between the interlayer and the active layer of the quantum structure closest to the n-doped layer may be at least 0 nm or at least 10 nm and / or at most 300 nm or at most 200 nm, for example. According to at least one embodiment of the optoelectronic semiconductor body, a hole barrier layer is arranged between the interlayer and the active region. For example, the hole barrier has a higher band gap than the interlayer. For example, the hole barrier layer is free of arsenide. Further, an optoelectronic semiconductor chip comprising a semiconductor body as described above is specified. For example, the optoelectronic semiconductor chip is an LED, a laser such as an edge emitting semiconductor laser or a surface emitting laser, a photodetector or a solar cell. Further, a method of producing a semiconductor body is specified. In at least one embodiment of the method, the method comprises the steps of providing a growth substrate, growing an n-doped layer and doped with a group VI dopant, growing an interlayer on the n-doped layer, wherein the interlayer comprises phosphorus and at least a further group V material 2023PF01338 January 30, 2025 P2023,1492 WO N - 14 - and a step of growing an active region configured to emit and / or absorb radiation on the interlayer. In at least one embodiment of the method, the method comprises the steps of providing a growth substrate, growing an n-doped layer based on phosphide compound semiconductor material and doped with a group VI dopant, growing an interlayer on the n-doped layer, wherein the interlayer comprises arsenic and a step of growing an active region configured to emit and / or absorb radiation on the interlayer. After the growth of the n-doped layer, the supply of the group VI dopant is switched off or at least reduced. For example, a flux of the group VI is reduced at least by a factor of 2 or at least a factor of 5 or at least a factor of 10. Alternatively or in addition, the flux may be reduced to a flux corresponding to an equilibrium dopant density of at most 1 * 1017cm-3. The group VI dopant remaining as a surfactant on the growth surface during the epitaxial growth can be efficiently incorporated into the interlayer so that the interlayer acts as a segregation blocking layer. Thus, the interlayer reduces the amount of group VI dopants being incorporated into the active region, where they would act as defects that would negatively affect the generation or absorption of radiation by the active region. According to at least one embodiment of the method, the semiconductor body (2) is epitaxially grown by MOVPE (metalorganic vapor phase epitaxy) or MBE (molecular beam epitaxy) or CBE (chemical beam epitaxy). After the epitaxial growth, the produced epitaxial material may be processed into one or more semiconductor bodies and 2023PF01338 January 30, 2025 P2023,1492 WO N - 15 - singulated into one or more optoelectronic semiconductor chips. The method is particularly suited for the production of a semiconductor body as described above. Thus, features disclosed in connection with the optoelectronic semiconductor body may also apply for the method and vice versa. Features described above in connection with at least one embodiment of the method or the optoelectronic semiconductor body or the optoelectronic semiconductor chip can be combined with other features described in connection with at least one embodiment of the method or the optoelectronic semiconductor body or the optoelectronic semiconductor chip unless they are contradictory. In the exemplary embodiments and figures similar or similarly acting constituent parts are provided with the same reference signs. Generally, only the differences with respect to the individual exemplary embodiments are described. Unless specified otherwise, the description of a part or feature in one exemplary embodiment applies to a corresponding part or feature in another exemplary embodiment as well. In the Figures: Figure 1A shows an exemplary embodiment of an optoelectronic semiconductor body in sectional view; Figure 1B shows results of secondary ion mass spectrometry (SIMS) measurements for a semiconductor body as described above and for a reference sample; 2023PF01338 January 30, 2025 P2023,1492 WO N - 16 -Figures 2A and 2B show diagrams illustrating the band gap EGand the lattice constant d for binary and ternary III-V compound semiconductor materials, silicon, and germanium; Figure 3 shows an exemplary embodiment of an optoelectronic semiconductor chip; and Figure 4A to 4D show an exemplary embodiment of a method of producing an optoelectronic semiconductor body by way of intermediate steps shown in sectional view. The elements illustrated in the figures and their size relationships among one another are not necessarily true to scale. Rather, individual elements or layer thicknesses may be represented with an exaggerated size for the sake of better representability and / or for the sake of better understanding. The optoelectronic semiconductor body with a semiconductor layer sequence 2 illustrated in Figure 1A comprises an n- doped layer 21 doped with a group VI dopant. For example, the group VI dopant is tellurium, selenium or sulfur. The semiconductor layer sequence 2 further comprises an active region 20 configured to emit and / or absorb radiation. For example, the semiconductor layer sequence is configured to emit radiation in the visible or in the near infrared spectral range. The semiconductor layer sequence 2 further comprises an interlayer 23 between the active region 20 and the n-doped semiconductor layer 21. The interlayer 23 comprises phosphorus and at least one further group V material. For example, the further group V material may be arsenic. 2023PF01338 January 30, 2025 P2023,1492 WO N - 17 - Alternatively, the interlayer 23 may be free of phosphorous. For example, the interlayer 23 free of phosphorous may comprise arsenic as single group V material or a combination of arsenic and antimony as group V materials. As an example, Figure 1B shows SIMS measurements for a semiconductor body of an LED structure configured for a peak emission wavelength of 730 nm. The interlayer 23 is located within a weakly doped region 22 arranged between the active region 20 and the n-doped layer 21. In this example, the n- doped layer 21 is nominally free of arsenic. The n-doped layer 21 and the weakly doped region 22, except for the interlayer 23, are based on the ternary materialsystem AlxIn1-xP with an aluminum content of 0.51. Theinterlayer 23 is based on the quaternary material systemAlxIn1-xAsvP1-v.Curve 61 of Figure 1B illustrates the aluminum signal in arbitrary units as a function of the depth z in arbitrary units. Curve 62 illustrates the tellurium signal and curve 63 illustrates the arsenic signal. Further, Figure 1B shows corresponding measurements 61R, 62R, 63R for a reference sample that comprises essentially the same structure as the semiconductor body described in connection with Figure 1A, except that the interlayer 23 is omitted. In the exemplary embodiment of Figure 1A, the active region 20 comprises a multi quantum well (MQW) structure with a plurality of quantum wells as active layers 201 with barrier layers 202 arranged between adjacent active layers 201. 2023PF01338 January 30, 2025 P2023,1492 WO N - 18 - Alternatively, a single active layer 201 may also be sufficient. Further, the active region 20 may also include at least one active layer 201 comprising quantum dots. The active region 20, in particular the active layers 201 of the active region 20, are based on the quaternary material system Ga1-yInyAs1-uPu. For example, the active layers 201 may be based on pure phosphide compound semiconductor material (u = 1). Alteratively, the active layers may comprise arsenic and phosphorous as group V materials (u < 1). The barrier layers 202 of the active region 20 may be based on a phosphide compound semiconductor material, for example. As Figure 1B illustrates, the supply of the group VI dopant tellurium is shut off at a transition 28 between the n-doped layer 21 and the weakly doped region 22. Starting from the transition 28, the dopant concentration continuously decreases in a subregion 27 towards the active region 20 due to dopant segregation as the tellurium present at the surface of the epitaxial material after the deposition of the n-doped layer 21 is very slowly incorporated into the arsenic free n- doped layer 21. As curve 62R shows, the dopant segregation results in the reference sample in a local maximum 29R of the dopant concentration located within the active region 20. This is because the arsenic present in the material of the active region 20 strongly enhances the incorporation of the surface adsorbed Te dopants which are remaining from the tellurium segregation. These tellurium dopants in the active region 20 act as undesirable defects leading to a degraded efficiency. 2023PF01338 January 30, 2025 P2023,1492 WO N - 19 - In the semiconductor body with the semiconductor layer sequence 2 as described in connection with Figure 1A in contrast the surface adsorbed dopants are efficiently consumed during the growth of the interlayer 23. Thus, a local maximum 29 of the group VI dopant concentration occurs at the interlayer 23. This consumption of the surface adsorbed group VI dopants prior to the growth of the active region 20 results in a strongly reduced incorporation of the group VI dopant into the active region 20, in particular into the active layers 201 thereof. As the segregation of the group VI dopant can be efficiently blocked by means of the interlayer 23, a distance d1 between the active layer 201 of the active region 20 closest to the n-doped layer 21 and the n-doped layer 21 can be kept comparably small. For instance, the distance d1 is at least 50 nm. A distance d2 between the interlayer 23 and the active layer 201 closest to the interlayer 23 is at least 10 nm, for example. In the exemplary embodiment of Figure 1A the interlayer 23 is arranged in the weakly doped region 22 between a weakly doped layer 24 and a hole barrier layer 25. A comparably large band gap of the hole barrier layer 25 may help to efficiently block holes from reaching the n-side of the semiconductor layer sequence 2 during operation of the semiconductor body. However, the hole barrier layer 25 may also be dispensed with. A thickness of the interlayer 23 is in a range from 1 nm to 300 nm, for example. For example, the thickness of the interlayer 23 is 10 nm. 2023PF01338 January 30, 2025 P2023,1492 WO N - 20 - The arsenic content v is at least 1 % or at least 2 % or at least 5 %. In the exemplary embodiment shown in Figure 1B the arsenic content v is 0.12 together with an indium content y of 0.43 such that an Al1-yInyAsvP1-vlayer, which is nearly lattice matched with respect to gallium arsenide, can be obtained. In particular, the lattice mismatch is sufficiently small such that no dislocation defects are formed due to the layer thickness exceeding the critical layer thickness. However, other materials may also be used for the layers of the semiconductor layer sequence 2. The semiconductor layer sequence may also comprise two or more interlayers 23. For example, the interlayers may be part of a superlattice wherein the interlayers are separated from one another by further superlattice layers having a larger electronic bandgap than the interlayers. Figure 2A illustrates binary and ternary III-V compound semiconductor materials that can be obtained using aluminum, gallium and / or indium as group III element(s) and phosphorus, arsenic and / or antimony as group V element(s). The composition of the compound semiconductor material may be selected such that a lattice matched or pseudomorphic growth of the material on gallium arsenide as a growth substrate may be obtained. Line 70, illustrated in Figure 2A, refers to an exact lattice match with respect to gallium arsenide. Line 71 refers to a lattice mismatch of -9000 ppm (tensile strain). Line 72 refers to a lattice mismatch of +9000 ppm (compressive strain). 2023PF01338 January 30, 2025 P2023,1492 WO N - 21 - Region 7 illustrates a region that can be obtained by varying the concentration of the group III and the group V materials such that the lattice mismatch is at most + / - 9000 ppm. It is noted that germanium may also be used as a growth substrate. For comparison, region 75 illustrated in Figure 2B corresponds to the case where only the group III materials are varied, and phosphorus is used as the only group V element (InGaAlP). The growth of materials from this material system can be precisely controlled because the semiconductor material is typically grown using very high group V to group III ratios so that the group III supply is limiting the growth rate. Due to the strong segregation of group VI dopants, however, this pure phosphide material bears the risk of the n-dopant being unintentionally incorporated into the active region 20 of the semiconductor layer sequence 2. Therefore, the interlayer 23 based on the unusual compound semiconductor material comprising at least two group V materials results in more efficient devices even though compound semiconductor materials comprising more than one group V element are more difficult to control during epitaxial growth. As for the interlayer 23, the phosphorus content v may be in a range from 1 % to 99 %. The arsenic content v may be in a range from 0 % to 99 % or in a range from 0 % to 100 %. The content of antimony may be in a range from 0 % to 40 %. These percentages each refer to the group V lattice sites. 2023PF01338 January 30, 2025 P2023,1492 WO N - 22 - Alternatively, the interlayer 23 may be a pure arsenide layer free of phosphorous. As for the group III elements, the gallium content may be in a range from 0 % to 100 %, the aluminum content may be in a range from 0 % to 100 % and the indium content y may be in a range from 0 % to 60 %. These percentages each refer to the group III lattice sites. The material for the active region 20, in particular for the active layers 201, may be selected such that the desired transition energy is obtained. For example, the material system GaInAsP may be used for a light emission with a peak emission wavelength between 600 and 1000 nm. The active region may be free of arsenic for shorter wavelengths. Alternatively or in addition, the semiconductor body may also be used for the absorption of electromagnetic radiation. For example, the semiconductor body may convert the electromagnetic radiation into an electric current. An exemplary embodiment of an optoelectronic semiconductor chip 1 is illustrated in Figure 3. The optoelectronic semiconductor chip 3 comprises an optoelectronic semiconductor body 2 as described in connection with Figure 1A. The optoelectronic semiconductor chip 1 further comprises an n-contact 401 and a p-contact 402. In the exemplary embodiment shown, the n-contact 401 and the p-contact 402 are arranged on different sides of the semiconductor body with the semiconductor layer sequence 2. However, the p-contact 42 and the n-contact 41 may also be arranged on the same side of the semiconductor body. 2023PF01338 January 30, 2025 P2023,1492 WO N - 23 - Further, the growth substrate 3 is not required in the optoelectronic semiconductor chip 1. Rather, it can also be removed and replaced by a carrier which is different from the growth substrate 3. For example, the optoelectronic semiconductor chip 1 is an LED, a laser, a photodetector or a solar cell. Figures 4A to 4D illustrate an exemplary embodiment of a method of producing an optoelectronic semiconductor body. As illustrated in Figure 4A, a growth substrate 3 is provided. For example, the growth substrate is a gallium arsenide or germanium substrate. An n-doped layer 21 is grown as illustrated in Figure 4B on the growth substrate. During the growth of the n-doped layer, a group VI dopant is provided so that a highly doped n- conducting layer may be obtained. As illustrated in Figure 4C, an interlayer 23 is grown on the n-doped layer 21 wherein the interlayer comprises phosphorus and at least one further group V material. In the exemplary embodiment of Figure 4C the interlayer 23 is located within a weakly doped region 22 which is epitaxially grown after the supply of the group VI dopant has been turned off or reduced to a level corresponding to a dopant concentration smaller than 5 * 1017cm-3, for example. As described in connection with Figure 1B, the surface adsorbed group VI dopants gradually decay slowly during the growth of the weakly doped region 22. At the interlayer 23, however, the remaining group VI dopants are quickly 2023PF01338 January 30, 2025 P2023,1492 WO N - 24 - incorporated into the semiconductor material due to the further group V material, such as arsenic. This effect likewise occurs, if the interlayer 23 is a pure arsenide layer free of phosphorous. Subsequently, the active region 20 and a p-doped layer 26 are grown on the interlayer 23 as illustrated in Figure 4D. The strongly suppressed surface accumulation of the group VI dopant allows an active region 20 of high quality to be grown. In particular, a high material quality of the active region 20 is obtained even if the active region 20 comprises arsenic. This patent application claims the priority of German patent application 102024 103 298.7, the disclosure content of which is hereby incorporated by reference. The invention described herein is not restricted by the description given with reference to the exemplary embodiments. Rather, the invention encompasses any novel feature and any combination of features, including in particular any combination of features in the claims, even if this feature or this combination is not itself explicitly indicated in the claims or exemplary embodiments.

[0002] 2023PF01338 January 30, 2025 P2023,1492 WO N - 25 - References 1 optoelectronic semiconductor chip 2 optoelectronic semiconductor body with semiconductor layer sequence 20 active region 201 active layer 202 barrier layer 21 n-doped layer 22 weakly doped region 23 interlayer 24 weakly doped layer 25 hole barrier layer 26 p-doped layer 27 subregion 28 transition 29 local maximum 29R local maximum of reference sample 3 substrate 41 n-contact 42 p-contact 61 aluminum signal 61R aluminum signal of reference sample 62 tellurium signal 62R tellurium signal of reference sample 63 arsenic signal 63R arsenic signal of reference sample 7 region 70 line 71 line 72 line 2023PF01338 January 30, 2025 P2023,1492 WO N - 26 - 75 region d1 distance d2 distance

Claims

2023PF01338 January 30, 2025 P2023,1492 WO N - 27 - Claims 1. An optoelectronic semiconductor body with a semiconductor layer sequence (2) based on a III-V compound semiconductor material, wherein - the semiconductor layer sequence (2) comprises an n-doped layer (21) doped with a group VI dopant; - the semiconductor layer sequence (2) comprises an active region (20) configured to emit and / or absorb radiation; - the semiconductor layer sequence (2) comprises an interlayer (23) between the active region (20) and the n- doped semiconductor layer (21); and - the interlayer (23) comprises phosphorus and at least one further group V material.

2. The optoelectronic semiconductor body according to claim 1, wherein the further group V material is arsenic.

3. The optoelectronic semiconductor body according to claim 1 or 2, wherein at least 1% of the group V lattice sites is occupied with the further group V material.

4. The optoelectronic semiconductor body according to any one of the preceding claims, wherein the n-doped layer (21) is based on phosphide compound semiconductor material.

5. An optoelectronic semiconductor body with a semiconductor layer sequence (2) based on a III-V compound semiconductor material, wherein2023PF01338 January 30, 2025 P2023,1492 WO N - 28 - - the semiconductor layer sequence (2) comprises an n-doped layer (21) doped with a group VI dopant; - the n-doped layer (21) is based on phosphide compound semiconductor material; - the semiconductor layer sequence (2) comprises an active region (20) configured to emit and / or absorb radiation; - the semiconductor layer sequence (2) comprises an interlayer (23) between the active region (20) and the n- doped semiconductor layer (21); and - the interlayer (23) comprises arsenic.

6. The optoelectronic semiconductor body according to any one of the preceding claims, wherein the group VI dopant is tellurium, selenium, or sulfur.

7. The optoelectronic semiconductor body according to any one of the preceding claims, wherein a concentration of the group VI dopant has a local maximum (29) in the interlayer.

8. The optoelectronic semiconductor body according to any one of the preceding claims, wherein the semiconductor layer sequence (2) comprises a weakly doped region between the active region (20) and the n- doped semiconductor layer (21).

9. The optoelectronic semiconductor body according to claim 8, wherein a concentration of the group VI dopant in the weakly doped region (22) continuously decreases at least in a subregion (27) in a direction from the n-doped layer (21) towards the interlayer (23).2023PF01338 January 30, 2025 P2023,1492 WO N - 29 - 10. The optoelectronic semiconductor body according to any one of the preceding claims, wherein a lattice mismatch of the n-doped layer (21) and of the interlayer (23) is at most + / - 9000 ppm with respect to a growth substrate (3) of the semiconductor layer sequence (2).

11. The optoelectronic semiconductor body according to any one of the preceding claims, wherein the active region (20) comprises a quantum structure with at least one active layer (201).

12. The optoelectronic semiconductor body according to claim 11, wherein the active layer (201) (i) is based on phosphide compound semiconductor material or (ii) comprises arsenic and phosphorous as group V materials.

13. The optoelectronic semiconductor body according to any one of claims 11 to 12, wherein a barrier layer (202) of the active region (20) is based on phosphide compound semiconductor material.

14. The optoelectronic semiconductor body according to any one of claims 11 to 13, wherein a distance (d1) between the active layer (201) of the quantum structure closest to the n-doped layer and the n- doped layer is at least 50 nm.

15. The optoelectronic semiconductor body according to any one of the preceding claims, wherein a hole barrier layer (25) is arranged between the interlayer (23) and the active region (20).2023PF01338 January 30, 2025 P2023,1492 WO N - 30 - 16. An optoelectronic semiconductor chip (1) comprising a semiconductor body with a semiconductor layer sequence (2) according to any one of the preceding claims.

17. A method of producing an optoelectronic semiconductor body comprising the steps of: a) providing a growth substrate (3); b) growing an n-doped layer (21) that is doped with a group VI dopant; c) growing an interlayer (23) on the n-doped layer, wherein the interlayer (23) comprises phosphorus and at least one further group V material; d) growing an active region (20) configured to emit and / or absorb radiation on the interlayer.

18. A method of producing an optoelectronic semiconductor body comprising the steps of: a) providing a growth substrate (3); b) growing an n-doped layer (21) that is doped with a group VI dopant, wherein the n-doped layer (21) is based on a phosphide compound semiconductor material; c) growing an interlayer (23) on the n-doped layer, wherein the interlayer (23) comprises arsenic; d) growing an active region (20) configured to emit and / or absorb radiation on the interlayer.

19. The method according to claim 17 or 18, wherein the semiconductor body (2) is epitaxially grown by metal organic vapor phase epitaxy or molecular beam epitaxy or chemical beam epitaxy.2023PF01338 January 30, 2025 P2023,1492 WO N - 31 - 20. The method according to any one of claims 17 to 19, wherein a semiconductor body according to any one of claims 1 to 15 is produced.

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