Optoelectronic semiconductor body and method for manufacturing an optoelectronic semiconductor body

Abstract

Optoelectronic semiconductor body (100), comprising - a semiconductor layer sequence (1) comprising a first layer (10) of a first conductivity type, a second layer (12) of a second conductivity type and an active layer (11) arranged between the first layer (10) and the second layer (12), which absorbs or emits electromagnetic radiation during intended operation, - a plurality of injection areas (2) arranged side by side in a lateral direction, which are superimposed on the semiconductor layer sequence (1) wherein within each injection area (2) the semiconductor layer sequence (1) is doped such that within the entire injection area (2) the semiconductor layer sequence (1) has the same conductivity type as the first layer (10), wherein - each injection area (2) starting from the first layer (10) completely penetrates the active layer (11) and at least partially extends into the second layer (12) and each injection area (2) is laterally surrounded by a continuous band of the active layer (11) in which the active layer (11) is less or oppositely doped than in the injection area (2), - during operation, charge carriers at least partially move from the first layer (10) into the injection areas (2) and from there are injected directly into the active layer (11), where each injection area (2) a doping concentration of at least 10 18 dopants per cm 3 exhibits, and wherein the active layer (11) has a quantum well structure with at least one quantum well layer (110).

Description

[0001] An optoelectronic semiconductor body is described. Furthermore, a method for manufacturing an optoelectronic semiconductor body is described.

[0002] Publication US 2007 / 0057249A1 discloses a light-emitting semiconductor device with lateral current injection in the light-emitting region. Publication JP H05-251743A relates to a light-emitting device.

[0003] One problem to be solved is to specify an optoelectronic semiconductor body in which the injection of charge carriers into the active layer is particularly effective. Another problem to be solved is to specify a method for fabricating such an optoelectronic semiconductor body.

[0004] These tasks are solved by the subject matter and the method according to the independent patent claims. Advantageous embodiments and further developments are the subject of the dependent patent claims.

[0005] According to at least one embodiment, the optoelectronic semiconductor body comprises a sequence of semiconductor layers with a first layer of a first conductivity type, a second layer of a second conductivity type, and an active layer arranged between the first layer and the second layer.

[0006] The active layer is designed to emit or absorb electromagnetic radiation during normal operation and then convert it, for example, into an electronic or optical signal. The first layer can be, for example, a p-doped layer with holes as charge carriers. The second layer is then, for example, an n-doped layer with electrons as charge carriers. Alternatively, the two layers can also be doped in the opposite way or with the same doping, for example, n- or p-doped. The conductivity type, as used here and in the following, refers to the majority charge carriers, i.e., electrons in n-doped layers and holes in p-doped layers.

[0007] The first and / or second layer can each refer to a sequence of several individual layers. For example, the first layer comprises all semiconductor layers between the first main face of the semiconductor layer sequence and the active layer. The second layer can, for example, comprise all layers between the second main face of the semiconductor layer sequence, opposite the first main face, and the active layer.

[0008] The semiconductor layer sequence is based, for example, on a III / V compound semiconductor material. This semiconductor material could be, for instance, a nitride compound semiconductor material such as Al. n In 1-n-m Ga m N, or a phosphide compound semiconductor material, such as Al n In 1-n-m Ga m P, or also an arsenide compound semiconductor material, such as Al n In 1-n-m Ga m As or Aln In 1-n-m Ga m AsP, where 0 ≤ n ≤ 1, 0 ≤ m ≤ 1, and m + n ≤ 1. The semiconductor layer sequence can contain dopants and additional components. For simplicity, however, only the essential components of the crystal lattice of the semiconductor layer sequence, i.e., Al, As, Ga, In, N, or P, are specified, even though these may be partially replaced and / or supplemented by small amounts of other substances. Preferably, the semiconductor layer sequence is based on AlInGaN.

[0009] The active layer of the semiconductor layer sequence includes, in particular, at least one pn junction and / or at least one quantum well structure. Radiation generated by the active layer during operation lies, in particular, in the spectral range between 400 nm and 800 nm inclusive.

[0010] The semiconductor body comprises a plurality of injection regions arranged side by side in a laterally oriented direction. Within each injection region, the semiconductor layer sequence is doped such that the semiconductor layer sequence exhibits the same conductivity type as the first layer throughout the entire injection region. The injection region is thus a doped subregion of the semiconductor layer sequence, for example, a p-doped region if the first layer is also p-doped. The lateral direction is understood to mean, in particular, a direction parallel to a principal orientation of the semiconductor layer sequence.

[0011] Each injection region extends from the first layer into the active layer and completely penetrates it. Preferably, each injection region is laterally surrounded by a continuous band of the active layer, in which the active layer is less or oppositely doped than in the injection region itself. Thus, the injection region is bounded or defined laterally by a transition from a doped region to a less or oppositely doped region.

[0012] In a cross-sectional view along the active layer, the injection area can, for example, have circular, oval, hexagonal, or rectangular cross-sectional shapes. In this view, the injection area is preferably completely and uninterruptedly surrounded by the active layer.

[0013] Preferably, each injection region differs from the surrounding semiconductor layer sequence, particularly from the surrounding active layer, only in its degree or type of doping. The material composition of the semiconductor layer sequence and the injection regions are then, for example, identical, except for the concentration of the dopant. Furthermore, the geometric orientation of the layers of the semiconductor layer sequence is preferably not influenced by the injection region.

[0014] However, it is also possible that the high doping level alters the concentration of essential components of the crystal lattice within the injection area. In particular, the high doping level can cause the migration of essential components of the crystal lattice, such as indium in an AlInGaN semiconductor layer sequence, to the surrounding area. This process is called segregation. The indium content within an injection area is then higher or lower compared to the indium content of the adjacent semiconductor layer sequence, for example, by at least 10% or 50%.

[0015] According to at least one embodiment, during operation of the semiconductor body, charge carriers migrate at least partially from the first layer into the injection areas and are injected from there directly into the active layer. The injection areas and the adjacent active layer are therefore in direct electrical contact with each other and are not separated or electrically isolated by any further layers, such as insulating layers.

[0016] In at least one embodiment, the optoelectronic semiconductor body comprises a sequence of semiconductor layers with a first layer of a first conductivity type, a second layer of a second conductivity type, and an active layer arranged between the first and second layers, which absorbs or emits electromagnetic radiation during intended operation. The semiconductor body contains a plurality of injection areas arranged laterally adjacent to one another, wherein within each injection area the sequence of semiconductor layers is doped such that the semiconductor layer sequence within the entire injection area has the same conductivity type as the first layer. Each injection area extends at least partially through the active layer, starting from the first layer.Furthermore, each injection region is laterally surrounded by a continuous band of the active layer, in which the active layer is less doped or oppositely doped than in the injection region. During operation of the semiconductor body, charge carriers migrate at least partially from the first layer into the injection regions and are injected directly from there into the active layer. The invention described here is based, among other things, on the finding that the internal quantum efficiency, particularly of nitride-based LEDs, is reduced by poor hole transport. Poor hole transport into the active layer is often inhibited by the barrier height of the quantum wells within the active layer. However, the presence of polarization charges also inhibits hole transport.

[0017] The invention described here utilizes, among other things, the idea of ​​selectively doping the active layer so that charge carriers, especially holes, can migrate from the first layer into the doped regions of the active layer and from there be effectively injected into the active layer, particularly across its entire thickness. When using a multi-quantum well structure, this enables charge carriers to be injected preferentially and uniformly into all quantum wells. This increases the efficiency of the entire semiconductor body.

[0018] The injection regions are superimposed on the grown semiconductor layer sequence. This means the semiconductor layer sequence is initially grown completely; only after growth are the injection regions introduced via a doping process. This has the particular consequence that the geometric orientation, especially of the active layer, is not influenced by the position and shape of the injection regions. The injection regions are therefore doped sub-regions within the semiconductor layer sequence, superimposed on the semiconductor layer sequence.

[0019] As a consequence, the positions of the injection areas are, on average, uncorrelated with the positions of any crystal defects within the semiconductor layer sequence. Such crystal defects can, for example, be in the form of lattice dislocations. Lattice dislocations arise, for instance, during the growth of the semiconductor layer sequence due to the adaptation of the lattice constant to the growth substrate. Preferably, these crystal defects or lattice dislocations are purely statistically distributed, meaning they do not exhibit a regular geometric arrangement within the semiconductor layer sequence.

[0020] For GaN-based semiconductor materials, the lattice dislocation density when growing on a sapphire substrate is typically 10 7 up to 10 9 per cm 2 , however, when growing on a GaN substrate, the lattice dislocation density can be several orders of magnitude lower.

[0021] Particularly in nitride-based semiconductor materials, V-shaped indentations, so-called V-pits, occur in the active layer due to such lattice dislocations. These indentations in the active layer typically have depths perpendicular to the main direction of extension of the active layer of at least 30 nm or at least 100 nm.

[0022] In the invention described here, the V-pits that arise during the growth of the semiconductor layer sequence preferably bear no correlation whatsoever to the injection areas. That is, the position of the V-pits is, on average, uncorrelated with the position of the injection areas.

[0023] According to at least one embodiment, the probability of a lattice dislocation of the semiconductor layer sequence, in particular a V-pit, being found within an injection area is at most 50% or at most 10% or at most 1%.

[0024] According to at least one embodiment, the active layer is planar throughout at least 50%, 90%, or 99% of the injection areas. In this context, "planar throughout" means that the active layer has no steps, structures, or indentations within the entire injection area whose depth perpendicular to the main direction of extension of the active layer exceeds 10 nm or 20 nm. Alternatively or additionally, on average, at least 50%, 90%, or 99% of the area of ​​the active layer within each injection area is planar.

[0025] Each injection area has a doping concentration of at least 10 18 or 10 19 or 10 20 or 10 21 dopants per cm 3 Such a doping concentration is preferably present within the entire injection area.

[0026] According to at least one embodiment, the doping concentration within the active layer outside the injection areas is at least twice, five times, or ten times lower than in the injection areas, or opposite to that in the injection areas. For example, in GaN-based semiconductor materials, the active layer is lightly n-doped, while the injection areas are preferably p-doped.

[0027] The active layer has a quantum well structure with at least one or more quantum well layers. Between two adjacent quantum well layers, for example, at least one barrier layer is arranged. The band gaps between the valence band and conduction band are smaller in the quantum well layer region than in the barrier layer region. The wavelength of the radiation emitted during recombination within the quantum well layer can be adjusted by the width of the quantum well layer and the band gap present in the quantum well layer. The principal orientations of the barrier layers and the quantum well layers are essentially parallel to the principal orientation of the active layer. The width is measured perpendicular to the principal orientation.

[0028] The presence of injection areas within the quantum well structure enables, for example, the injection of charge carriers from the first layer to be distributed evenly across all quantum well layers during operation, thereby increasing the quantum efficiency of the device compared to devices without injection areas.

[0029] According to at least one embodiment, the injection areas taper in a direction away from the first layer. For example, the injection areas can be pyramid-shaped, conical, or dome-shaped. Hemispheres or semi-ellipsoids of rotation are also conceivable.

[0030] The injection areas completely penetrate the active layer and extend at least partially into the second layer. Preferably, the injection areas extend at least 50 nm, 100 nm, or 150 nm into the second layer. Alternatively or additionally, the injection areas extend at most 300 nm, 250 nm, or 200 nm into the second layer.

[0031] According to at least one embodiment, the semiconductor layer sequence is based on a nitride compound semiconductor material; in particular, all layers of the semiconductor layer sequence are based on a nitride compound semiconductor material.

[0032] According to at least one embodiment, the first layer and the injection areas are p-doped and have holes as the first conductivity type.

[0033] The active layer can, for example, have a quantum well structure based on AlGaInN.

[0034] According to at least one embodiment, the injection areas are arranged on grid points of a regular grid when viewed from above on the active layer. In particular, the injection areas are then distributed along the active layer in a matrix-like or hexagonal pattern. The arrangement of the injection areas along the active layer is therefore preferably not arbitrary, but follows a pattern and is periodic or regular.

[0035] According to at least one embodiment, the injection areas within the active layer have a diameter or width, measured in the lateral direction, of at least 100 nm, at least 150 nm, or at least 200 nm. Alternatively or additionally, the diameter or width of the injection areas is at most 500 nm, at most 250 nm, or at most 200 nm. The diameter or width is, for example, the maximum or average diameter or the maximum or average width.

[0036] According to at least one embodiment, the first layer has a thickness perpendicular to the main direction of extension of the semiconductor layer sequence of at most 1 µm, preferably at most 0.5 µm. The thickness of the second layer is preferably in the range between 3 µm and 6 µm inclusive. The thickness of the active layer is, for example, between 50 nm and 200 nm inclusive and can, for example, comprise five to ten quantum well layers.

[0037] According to at least one embodiment, the area coverage of the injection areas along the entire active layer is at least 0.5%, at least 1%, or at least 2%. Alternatively or additionally, the area coverage is at most 30%, at most 10%, or at most 3%. By choosing such an area coverage density, effective injection of the charge carriers into the active layer is enabled on the one hand, while on the other hand, enough area of ​​the active layer remains free of injection areas to guarantee a high light yield.

[0038] According to at least one embodiment, the doping concentration is homogeneous and constant within each entire injection area. Alternatively, the doping concentration within the injection areas can also exhibit a gradient, such that the doping concentration decreases continuously from the inside out in a lateral direction. A gradient of the doping concentration perpendicular to the main direction of extension of the active layer is also conceivable. For example, the doping concentration then decreases in the direction away from the first layer within the injection area.

[0039] According to at least one embodiment, the semiconductor layer sequence is deposited on a substrate. The substrate can be located on either the side of the semiconductor layer sequence facing away from or towards the first layer. In particular, the substrate can be the growth substrate for the semiconductor layer sequence or a subsequently applied auxiliary substrate. The substrate serves, in particular, to stabilize and mechanically support the semiconductor layer sequence. For example, the semiconductor body is then designed as a self-supporting surface emitter or volume emitter. It is possible, for instance, that the semiconductor body is a sapphire chip or a thin-film chip.

[0040] Furthermore, a method for manufacturing an optoelectronic semiconductor body is disclosed. This method is particularly suitable for manufacturing the optoelectronic semiconductor body described herein. That is to say, all features disclosed in connection with the optoelectronic semiconductor body are also disclosed for the method, and vice versa.

[0041] According to at least one embodiment, the method for manufacturing an optoelectronic semiconductor body comprises a step A in which a semiconductor layer sequence of a first layer of a first conductivity type, a second layer of a second conductivity type and an active layer arranged between the first layer and the second layer is provided, wherein, in intended operation, electromagnetic radiation is absorbed or emitted by the active layer.

[0042] In a subsequent step B, the semiconductor layer sequence is then selectively doped in at least one laterally defined and laterally bounded injection region. In step B, the doping is carried out such that the semiconductor layer sequence exhibits the same conductivity type as the first layer throughout the entire injection region. Preferably, the resulting injection region extends from the first layer at least partially through the active layer. After doping in step B, the injection region is then, for example, laterally partially or completely surrounded by a continuous and uninterrupted path of the active layer, in which the active layer is less densely doped or doped in the opposite direction than in the injection region.

[0043] According to at least one embodiment, in step B a mask is applied to the side of the first layer facing away from the active layer. The mask preferably has at least one window through which the semiconductor layer sequence is exposed. Areas of the semiconductor layer sequence outside the window are covered by the mask.

[0044] According to at least one embodiment, doping is carried out by an ion implantation process, wherein dopant atoms are injected onto the mask from a side of the mask facing away from the active layer. Doping of the semiconductor layer sequence then takes place in the region of the window, preferably exclusively in the region of the window. Doping below the mask is preferably suppressed by the mask, and in particular completely suppressed.

[0045] According to at least one embodiment, a mask layer is first applied to the semiconductor layer sequence for the production of the mask. Subsequently, the mask is structured using a lithography process, such as a stepper process or a nanoimprint lithography process, thereby creating at least one window in the mask layer.

[0046] According to at least one embodiment, the mask comprises or consists of a metal such as gold, silver, aluminum, titanium, or steel. It is also conceivable that the mask is made of or contains a photoresist.

[0047] According to at least one embodiment, after the ion implantation process for doping the injection area, the semiconductor layer sequence is subjected to a thermal annealing process. During this annealing process, some defects or lattice flaws generated by the ion implantation process can regress or heal. This, in turn, can increase the optical efficiency of the semiconductor body. For the annealing process, the semiconductor layer sequence is heated, for example, to a temperature of at least 1000 °C.

[0048] According to at least one embodiment, the semiconductor layer sequence is grown on a growth substrate before step A, with the second layer being grown first, then the active layer, and then the first layer. Subsequently, in step B, the semiconductor layer sequence is doped from a side facing away from the growth substrate, for example, by ion implantation. After step B, an auxiliary carrier is applied to the side of the semiconductor layer sequence facing away from the growth substrate, and the growth substrate is removed. In this way, for example, a thin-film semiconductor chip with the injection areas mentioned above can be produced. Alternatively, the growth substrate can remain in the semiconductor body, and an auxiliary carrier can be omitted. In this way, for example, a bulk semiconductor chip such as a sapphire chip could be produced.The growth substrate can be, for example, a silicon, GaAs, GaN, SiC, or sapphire growth substrate.

[0049] The following section provides a more detailed explanation of an optoelectronic semiconductor body and a method for its fabrication, with reference to the drawings and exemplary embodiments. Identical reference numerals indicate identical elements in the individual figures. However, the figures are not to scale; rather, individual elements may be exaggerated for clarity.

[0050] They show: Fig. 1A, Fig. 4A and Fig. 4B Exemplary embodiments of an optoelectronic semiconductor body in top view, Fig. 1B, Fig. 1C and Fig. 2 Examples of an optoelectronic semiconductor body in cross-sectional view and Fig. 3A to 3C Examples of process steps for the production of an optoelectronic semiconductor body in cross-sectional view.

[0051] In Fig. Figure 1A shows a top view of an optoelectronic semiconductor body 100, specifically an active layer 11 of a semiconductor layer sequence 1 of the optoelectronic semiconductor body 100. The active layer 11 is interspersed with injection areas 2, which are arranged regularly in a rectangular or square matrix pattern. The injection areas 2 have a circular or elliptical cross-sectional area. In particular, in Fig. 1A the injection areas 2 are not randomly distributed within the semiconductor layer sequence 1, but are arranged on fixed lattice points of a regular lattice.

[0052] Fig. Figure 1B shows an embodiment of an optoelectronic semiconductor body 100 along the line AA' from Fig. 1A. It can be seen that the semiconductor body 100 has a support 13 on which a semiconductor layer sequence 1 is deposited. The semiconductor layer sequence 1 can, for example, be grown on a main surface of the support 13. The support 13 is, for example, the growth substrate for the semiconductor layer sequence 1. The support 13 is, for example, a sapphire support, and the semiconductor layer sequence 1 is, for example, based on AlInGaN.

[0053] The semiconductor layer sequence 1 comprises a first layer 10 of a first conductivity type, an active layer 11, and a second layer 12 of a second conductivity type, wherein the active layer 11 is arranged between the first layer 10 and the second layer 12, and the second layer 12 faces the support 13. In this case, the first layer 10 is, for example, p-doped, and the second layer 12 is, for example, n-doped. The active layer 11 can be undoped or, for example, lightly n-doped.

[0054] In Fig. 1B is also the cross-section of the injection area 2 from the Fig. 1A is recognizable. The injection area 2 is a doped subregion of the semiconductor layer sequence 1, the doping being chosen such that the entire injection area 2 exhibits the same conductivity type as the first layer 10. For example, the injection area 2, like the first layer 10, is p-doped and has holes as the majority charge carriers. The doping concentration within the injection area 2 is, for example, at least 10 18 dopants per cm 3 The dopant atoms are, for example, Mg.

[0055] The injection area 2 is superimposed on the semiconductor layer sequence 1 in such a way that the position and geometric shape of the injection area 2 have no influence on the orientation of the layers within the semiconductor layer sequence 1. In particular, the injection area 2 is based on the same substrate material as the semiconductor layer sequence 1 and is only additionally or more heavily doped compared to the rest of the semiconductor layer sequence 1. The active layer 11 is planar throughout the entire injection area 2 and has no steps or indentations with a vertical extent of more than 20 nm. Vertical here refers to a direction perpendicular to the main orientation of the active layer 11. In particular, there is no lattice defect, for example in the form of a V-pit 4, within the injection area 2.The probability of finding any lattice defect, such as a lattice dislocation or a V-pit 4, within an injection area 2 is preferably at most 50%. A V-pit 4 is located laterally next to the injection area 2. In cross-sectional view, the V-pit 4 is a V-shaped indentation in the active layer 11.

[0056] Injection area 2 extends into Fig. 1B extends through the entire first layer 10 and the entire active layer 11 and partially, for example at least 50 nm, into the second layer 12. The injection area 2 tapers away from the first layer 10. Laterally, that is, parallel to a principal direction of extension of the semiconductor layer sequence 1, the injection area 2 is completely surrounded by a continuous and uninterrupted path of the active layer 11, in which the doping level is opposite to or at least two orders of magnitude lower than in the region of the injection area 2. In this case, the cross-sectional shape of the injection area 2 is dome-shaped.

[0057] In Fig. 1C is a cross-sectional view through the semiconductor body 100 along line BB' from the Fig. Figure 1A shows that line BB' does not cross injection area 2 of semiconductor layer sequence 1. The layer structure of semiconductor layer sequence 1 is identical to that of [the other figure], except for injection area 2. Fig. 1B. In particular, the geometric profile of the active layer 11 in Fig. 1B and Fig. 1C except for the random one in Fig. The V-pit 4 appearing in 1B is identical. This illustrates that the course of the active layer 11 is not influenced by the position and shape of the injection area 2.

[0058] In Fig. Figure 2 shows an embodiment of the semiconductor body 100, again in cross-sectional view. Here, the active layer 11 is formed from a quantum well structure with a plurality of quantum well layers 110 and barrier layers 111, which are stacked alternately on top of each other. The active layer 11 has, for example, a thickness between 50 nm and 200 nm inclusive. The quantum well layers 110 each have, for example, a thickness between 2 nm and 10 nm inclusive. The quantum well structure of the Fig. 2 is based, for example, on AlInGaN and has between ten and 20 quantum well layers 110. The band gaps within the quantum well layers 110 are preferably smaller than within the barrier layers 111.

[0059] Furthermore, it shows Fig. 2. The flow of charge carriers within the layers of the semiconductor layer sequence 1 during the operation of the semiconductor body 100. Initial charge carriers, for example holes, are injected from the first layer 10 into the injection region 2. From the injection region 2, the initial charge carriers can directly enter the active layer 11. The initial charge carriers are distributed across all quantum well layers 110, so that initial charge carriers are injected into each quantum well layer 110.

[0060] The first charge carriers are thus preferentially distributed across all quantum well layers 110, and in particular, distributed uniformly. Furthermore, second charge carriers, for example electrons, are also injected from the second layer 12 into the active layer 11 and the associated quantum well layers 110. Within the quantum well layers 110, recombination of electrons and holes can then occur, resulting in the generation of electromagnetic radiation, preferably in the UV or visible range. The injection area 2 enables radiation generation to take place in all quantum well layers 110, thus increasing the quantum efficiency of the semiconductor body 100 compared to semiconductor bodies without injection areas.

[0061] In the exemplary embodiments of the Fig. Figures 3A to 3C show various process steps for the fabrication of an optoelectronic semiconductor body 100. The semiconductor body 100 is shown in cross-sectional view in each case.

[0062] In Fig. 3A initially provides a semiconductor layer sequence 1 on a support 13. The sequence of the individual layers of the semiconductor layer sequence 1 corresponds to the sequence from the Fig. 1C. A mask 3, for example made of a metal such as aluminum, silver, or gold, is also applied to a side of the first layer 10 facing away from the support 13. The mask 3 further has a window 30 through which the side of the semiconductor layer sequence 1 facing away from the support 13 is exposed. The remainder of the semiconductor layer sequence 1 is covered by the mask 3.

[0063] Furthermore, it illustrates Fig. 3A the start of an ion implantation process in which, for example, ionized magnesium atoms are shot onto a side of the mask 3 facing away from the carrier 13.

[0064] In Fig. Figure 3B shows a process step after the doping process by ion implantation has been completed. The doping process has created an injection area 2 in the region of window 30, in which the semiconductor layer sequence 1 is doped. Below mask 3, in areas outside window 30, the semiconductor layer sequence 1 is either not doped or only minimally doped. Mask 3 has therefore shielded or trapped the ions from the ion implantation process.

[0065] In Fig. 3C is the same embodiment as in Fig. Figure 3B shows the process; only mask 3 was removed after the doping process. What remains is the finished optoelectronic semiconductor body 100.

[0066] Fig. 4A and Fig. Figure 4B shows further embodiments of an optoelectronic semiconductor body 100 in a top view of the active layer 11 of the semiconductor layer sequence 1. Fig. 4A the injection areas 2 are arranged in a regular hexagonal pattern, in Fig. In 4B, the injection areas 2 are arranged in a square matrix pattern. Fig. 4A the injection areas 2 have a round or oval cross-sectional shape, whereas in Fig. 4B the injection areas 2 have square cross-sectional shapes. The arrangement of the injection areas 2 as well as the geometric cross-sectional shape of the injection areas 2 can be determined via the geometric shape and the arrangement of the windows 30 in the mask 3.

[0067] Furthermore, it shows Fig.4A represents a plurality of lattice dislocations 4 in the form of V-pits 4, which have arisen due to growth in the semiconductor layer sequence 1. The V-pits 4 are randomly and not regularly or periodically distributed in the semiconductor layer sequence 1. In particular, the positions of the injection regions 2 do not correlate with the positions of the V-pits 4. Reference symbol list 1 Semiconductor layer sequence 2 Injection area 3 Mask 4 lattice dislocations / V-pits 10 first shift 11 active layer 12 second shift 13 carriers 30 windows 100 optoelectronic semiconductor bodies 110 quantum well layer 111 Barrier layer

Claims

[1] Optoelectronic semiconductor body (100), comprising - a semiconductor layer sequence (1) comprising a first layer (10) of a first conductivity type, a second layer (12) of a second conductivity type and an active layer (11) arranged between the first layer (10) and the second layer (12), which absorbs or emits electromagnetic radiation during intended operation, - a plurality of injection areas (2) arranged side by side in a lateral direction, which are superimposed on the semiconductor layer sequence (1) wherein within each injection area (2) the semiconductor layer sequence (1) is doped such that within the entire injection area (2) the semiconductor layer sequence (1) has the same conductivity type as the first layer (10), wherein - each injection area (2) starting from the first layer (10) completely penetrates the active layer (11) and at least partially extends into the second layer (12) and each injection area (2) is laterally surrounded by a continuous band of the active layer (11) in which the active layer (11) is less or oppositely doped than in the injection area (2), - during operation, charge carriers at least partially move from the first layer (10) into the injection areas (2) and from there are injected directly into the active layer (11), where each injection area (2) a doping concentration of at least 10 18 dopants per cm 3 exhibits, and wherein the active layer (11) has a quantum well structure with at least one quantum well layer (110). [2] Optoelectronic semiconductor body (100) according to claim 1, wherein - the injection areas (2) of the The semiconductor layer sequence (1) is superimposed in such a way that, on average, the positions of the injection areas (2) are uncorrelated with the positions of any crystal defects in the semiconductor layer sequence (1). [3] Optoelectronic semiconductor body (100) according to claim 1 or 2, wherein - the probability of finding a lattice dislocation of the semiconductor layer sequence (1) within an injection area (2) is at most 50%, - the active layer (11) is planar throughout at least 50% of the injection areas (2). [4] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - the doping concentration within the active layer (11) outside the injection areas (2) is at least two orders of magnitude lower or opposite to that in the injection areas (2). [5] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - at least one barrier layer (111) is arranged between each of two adjacent quantum well layers (110), - a band gap between the valence band and the conduction band in the region of the quantum well layer (110) is smaller than in the region of the barrier layer (111), - The main extension directions of the barrier layer (111) and the quantum well layer (110) run parallel to a main extension direction of the semiconductor layer sequence (1). [6] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - the injection areas (2) taper towards the outside of the first layer (10), - the injection areas (2) extend at least 50 nm and at most 300 nm into the second layer (12). [7] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - the semiconductor layer sequence (1) is based on a nitride compound semiconductor material, - the first layer (10) and the injection areas (2) are p-doped and have holes as the first conductivity type. [8] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - in top view of the active layer (11) the injection areas (2) are arranged on grid points of a regular grid. [9] Optoelectronic semiconductor body (100) according to any one of the preceding claims, where the injection areas (2) within the active layer (11) have a diameter in the lateral direction of at least 100 nm and at most 500 nm. [10] Optoelectronic semiconductor body (100) according to any one of the preceding claims, where the area coverage density of the injection areas (2) along the entire active layer (11) is between 0.5% and 30% inclusive. [11] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - the injection areas (2) taper towards the outside of the first layer (10) and are dome-shaped, - within the injection areas (2) the doping concentration decreases continuously from the inside out in a lateral direction. [12] Optoelectronic semiconductor body (100) according to any one of the preceding claims, wherein - the semiconductor layer sequence (1) is applied to a substrate (13), - the carrier (13) is applied to one of the sides of the semiconductor layer sequence (1) facing away from or towards the first layer (10), - the semiconductor body (100) is designed as a surface emitter or volume emitter. [13] Optoelectronic semiconductor body (100) according to any one of the preceding claims, where the semiconductor layer sequence (1) is an AlInGaN semiconductor layer sequence and the indium content within an injection area (2) is increased or reduced compared to the indium content of the adjacent semiconductor layer sequence (1). [14] Method for manufacturing an optoelectronic semiconductor body (100) comprising the steps: A) Providing a semiconductor layer sequence (1) comprising a first layer (10) of a first conductivity type, a second layer (12) of a second conductivity type and an active layer (11) arranged between the first layer (10) and the second layer (12), which absorbs or emits electromagnetic radiation during intended operation and which has a quantum well structure with at least one quantum well layer (110); B) targeted doping of the semiconductor layer sequence (1) in a plurality of laterally defined and laterally bounded injection areas (2) of the semiconductor layer sequence (1), wherein each injection area (2) has a doping concentration of at least 10 18 dopants per cm 3 exhibits and wherein - in step B) is doped such that within the entire injection area (2) the semiconductor layer sequence (1) has the same conductivity type as the first layer (10), - the injection area (2) starting from the first layer (10) completely penetrates the active layer (11) and extends at least partially into the second layer (12), - after doping in step B) the injection area (2) is laterally surrounded by a continuous path of the active layer (11) in which the active layer (11) is less or oppositely doped than in the injection area (2). [15] Method according to claim 14, wherein - before step B) a mask (3) is applied to the side of the first layer (10) facing away from the active layer (11), - the mask (3) has at least one window (30) in which the semiconductor layer sequence (1) is exposed, - the doping is carried out by an ion implantation process, whereby doping atoms are shot onto the mask (3) from a side of the mask (3) facing away from the active layer (11), - the semiconductor layer sequence (1) is doped in the area of ​​the window (30), - doping of the semiconductor layer sequence (1) below the mask (3) is suppressed by the mask (3). [16] Method according to claim 15, wherein - for the production of the mask (3) a mask layer is first applied to the semiconductor layer sequence (1), - subsequently, at least one window (30) is created in the mask layer using a lithography process or a nano-embossing lithography process, - the mask (3) contains a metal. [17] Method according to claim 15 or 16, wherein after the ion implantation process the semiconductor layer sequence (1) is subjected to a thermal curing process. [18] Method according to any one of claims 14 to 17, wherein - the semiconductor layer sequence (1) is grown on a growth substrate (4) prior to step A), whereby first the second layer (12), then the active layer (11) and then the first layer (10) is grown, - the doping of the semiconductor layer sequence (1) in step B) is carried out from a side facing away from the growth substrate (4), - after step B) an auxiliary carrier is applied to the side of the semiconductor layer sequence (1) facing away from the growth substrate (4) and the growth substrate (4) is removed.

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