METHOD FOR MANUFACTURING A SEMICONDUCTOR COMPONENT

Abstract

A method for manufacturing a semiconductor device comprising: introducing at least one first dopant into a semiconductor body (102) through a first surface (104) of the semiconductor body (102); and subsequently performing one or more proton implantations; introducing a second dopant into the semiconductor body (102) through the second surface (106) using a plasma-based ion implantation method, wherein the plasma-based ion implantation method is carried out with a complex of the second dopant and hydrogen as the process gas, and hydrogen of the complex is introduced into the semiconductor body (102) through the second surface (106) in addition to the second dopant, wherein the hydrogen is introduced into the semiconductor body in addition to the one or more proton implantations; and activating hydrogen-correlated donors.

Description

TECHNICAL AREA The application relates to a method for manufacturing a semiconductor device. BACKGROUND In the manufacture of semiconductor devices, e.g., power semiconductor devices such as insulated-gate bipolar transistors (IGBTs) or power diodes, compromises must be made in the required device properties. This is because, for example, a change in one device parameter can have different effects on the device properties, such as improving one property while simultaneously deteriorating another. Furthermore, the underlying technology for manufacturing the semiconductor device can lead to limitations in wafer processing, e.g., when processing thin or thinned wafers. For examples related to devices and manufacturing processes, see US 2016 / 0300938A1, US 2014 / 0073105A1, and Qin, S.; Chan, C.: An evaluation of contamination from plasma immersion ion implantation on silicon device characteristics.Referenced in: Journal of Electronic Materials, Vol. 23, 1994, No. 3, pp. 337-340. Against this background, this application deals with the improvement of a method for manufacturing a semiconductor device. SUMMARY The invention is defined in main claim 1. Further developments are the subject of the dependent claims. The present disclosure relates to a method for manufacturing a semiconductor device. The method comprises introducing at least one first dopant into a semiconductor body through a first surface of the semiconductor body. Subsequently, one or more proton implantations are performed. The method further comprises introducing a second dopant into the semiconductor body through a second surface opposite the first surface using a plasma-based ion implantation method, wherein the plasma-based ion implantation method is carried out with a complex of the second dopant and hydrogen as the process gas. The present disclosure also relates to a semiconductor device. The semiconductor device comprises a drift zone of a first conductivity type in a semiconductor body having opposing first and second surfaces. The semiconductor device also comprises a doped field-stop zone of the first conductivity type between the drift zone and the second surface, the field-stop zone being produced by introducing the second dopant according to the method described above. Further features and advantages of the disclosed item will become apparent to the person skilled in the art from the following detailed description and from the drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a schematic flowchart illustrating an exemplary process for manufacturing a semiconductor device with process features M10, M20, and M30. Fig. 2 shows a schematic cross-sectional view of a semiconductor body to illustrate process feature M10 of the embodiment shown in Fig. 1. Fig. 3 shows a schematic cross-sectional view of the semiconductor body to illustrate process feature M20 of the embodiment shown in Fig. 1. Fig. 4 shows a schematic representation of the semiconductor body to illustrate process feature M30 of the embodiment shown in Fig. 1. Fig. 5 is a schematic diagram illustrating concentration profiles that can be set using the process of the embodiment shown in Fig. 1. Fig. 6 is a schematic cross-sectional view of a semiconductor body manufactured using the process shown in Fig. 1.can be produced as shown in the exemplary embodiment 1. DETAILED DESCRIPTION The following detailed description refers to the accompanying drawings, which form part of the disclosure and show specific embodiments for illustrative purposes. In this context, directional terminology such as "top," "bottom," "front," "back," "front," "back," etc., refers to the orientation of the figures just described. Since the components of the embodiments can be positioned in different orientations, this directional terminology serves only for explanation and is in no way to be considered limiting. The terms "have," "contain," "comprise," "exhibit," and the like are, in the following, open terms that indicate the presence of the aforementioned elements or characteristics, but do not exclude the presence of further elements or characteristics. The indefinite and definite articles include both the plural and the singular, unless the context clearly indicates otherwise. The term "electrically connected" describes a permanent, low-resistance connection between electrically connected elements, for example, a direct contact between the elements in question or a low-resistance connection via a metal and / or a highly doped semiconductor. The term "electrically coupled" implies that one or more intermediate elements suitable for signal transmission may be present between the electrically coupled elements, for example, elements that are controllable to temporarily provide a low-resistance connection in a first state and a high-resistance electrical decoupling in a second state. Insulated-gate field-effect transistors (IGFETs) are voltage-controlled devices, such as metal-oxide-semiconductor FETs (MOSFETs). MOSFETs also include FETs with gate electrodes based on doped semiconductor material and / or gate dielectrics that are not based on an oxide, or not exclusively so. The term "horizontal," as used in this description, is intended to describe an orientation essentially parallel to a first or main surface of a semiconductor substrate or body. This could be, for example, the surface of the wafer or a die or chip. The term “vertical”, as used in the present description, is intended to describe an orientation that is essentially perpendicular to the first surface, i.e. parallel to the normal direction of the first surface of the semiconductor substrate or body. When a physical quantity is defined within a range of values ​​by specifying one or two limit values, the prepositions "from" and "to" include the respective limit values. A specification of the form "from ... to" is therefore understood as "from at least ... to at most". Figure 1 shows a schematic flowchart 100 for the fabrication of a semiconductor device according to an exemplary embodiment. The semiconductor device can be, for example, a power semiconductor device such as an IGFET, a MOSFET, an IGBT, a diode, or a thyristor. Flowchart 100 comprises process features, each of which can include one or more processing steps. During the manufacturing of the semiconductor device, further processing steps can occur, for example, before, between, or after the process features shown. Likewise, further processing steps can be performed between the processing steps assigned to a process feature or together with the described processing steps. Processing steps of different process features can also be performed together or in different sequences. For example, process feature M30, described below, can be performed before or after process feature M20. A process feature M10 comprises the introduction of at least one first dopant into a semiconductor body through a first surface of the semiconductor body. The first dopant is a dopant species that can be activated in the semiconductor body as p-type or n-type doping, e.g., a p-type dopant in silicon such as boron (B), indium (In), aluminum (Al), or gallium (Ga), or an n-type dopant in silicon such as phosphorus (P), arsenic (As), or antimony (Sb) in a semiconductor body made of, for example, silicon (Si). The semiconductor body can, for example, comprise a semiconductor substrate, e.g., a wafer made of a single-crystal semiconductor material such as silicon (Si), silicon germanium (SiGe), silicon carbide (SiC), or a III-V semiconductor material. The semiconductor body can also comprise zero, one, or multiple semiconductor layers, which, for example, are formed on the semiconductor substrate. The initial dopant can be introduced into the semiconductor body, for example, by ion implantation, diffusion from a diffusion source, or in-situ doping during layer deposition. Naturally, multiple diffusion steps, ion implantation steps, or a combination of both can be used for doping. A depth distribution of the initial dopant can be achieved, for example, by ion implantation at different energies or by a process in which epitaxy and implantation alternate multiple times (so-called "multi-epi / multi-implant" method). By introducing the initial dopant through the first surface into the semiconductor body, a functional semiconductor region of the n- or p-type can be formed, e.g.,a source, body or body terminal region of an IGFET, a junction FET (JFET) or an IGBT, a cathode or anode region of a diode or a thyristor, an emitter, base or collector region of a bipolar junction transistor (BJT), a doped region of an edge termination structure such as a junction termination extension (JTE) or a variation of lateral doping (VLD), a junction isolation structure, a resistor. A process feature M20 includes performing one or more proton implantations. The one or more proton implantations can be performed, for example, through the first surface and / or through a second surface of the semiconductor body opposite the first surface. The second surface can be, for example, the surface located on the back side of the semiconductor device, and the first surface can be, for example, the surface located on the front side of the semiconductor device. The semiconductor body can be connected, for example, via the second surface to a semiconductor substrate of a chip package, such as a leadframe, e.g., by a solder or low-temperature connection.A first load terminal and, depending on the device type, a control terminal can be formed on the first surface of the semiconductor body, and a second load terminal can be formed on the second surface of the semiconductor body. Thus, the semiconductor device can, for example, be a vertical power semiconductor device, where the term "vertical" refers to a current direction that runs essentially perpendicular to the first and second surfaces in the case of load current. In the case of a semiconductor device designed as an IGBT or BJT, the first load terminal can be an emitter terminal. In the case of a semiconductor device configured as a FET or JFET, the first load terminal can be a source terminal. In the case of a semiconductor device configured as a diode or thyristor, the first load terminal can be an anode (cathode) terminal. In the case of a semiconductor device configured as an IGBT or BJT, the second load terminal can be a collector terminal. Similarly, in the case of a semiconductor device configured as a FET or JFET, the second load terminal can be a drain terminal. In the case of a semiconductor device configured as a diode or thyristor, the second load terminal can be a cathode (anode) terminal. In the case of a semiconductor device configured as a FET, IGBT, or thyristor, the control terminal can be a gate terminal. In the case of a semiconductor device configured as a BJT, the control terminal can be a base terminal. The one or more proton implantations serve, for example, to form a field stop zone with one or more peaks in the dopant profile. A process feature M30 comprises the introduction of a second dopant into the semiconductor body through the second surface using a plasma-based ion implantation process, wherein the plasma-based ion implantation process is carried out with a complex of the second dopant and hydrogen as the process gas. Plasma-based ion implantation processes are known by a variety of names and abbreviations, which, without limitation, include the following: PSII (Plasma Source Ion Implantation), PIII or PI3 (Plasma Immersion Ion Implantation), PII or PI2 (Plasma Ion Implantation), PIP (Plasma Ion Plating), PIIID (Plasma Immersion Ion Implantation and Deposition), MePIIID (Metal Plasma Immersion Ion Implantation and Deposition), IonClad, PLAD (Plasma Doping), and PIIP (Plasma Ion Immersion Processing). Some of these names or abbreviations are synonymous; others emphasize a particular aspect, such as the presence of metal ions.Plasma-based ion implantation methods enable comparatively cost-effective high-dose implantation at low implantation energies. The technical approach described above is advantageous in several respects. In proton doping, doping, in simplified terms, occurs through the attachment of a hydrogen atom to crystal defects, such as those generated by implantation, particularly vacancies in the crystal lattice of the semiconductor. If insufficient hydrogen is available, the unsaturated crystal defects can lead to leakage currents or compensation of the hydrogen donors, which in turn can necessitate an increase in the implanted proton dose. Comparatively high proton doses may be required for proton-induced field stop zones, which can lead to an increase in manufacturing costs, especially when multiple peaks need to be implanted.If the number of required implantation steps at different energies is limited for cost reasons, this can lead, depending on the field stop design, to the hydrogen reservoirs introduced by the implantation along the corresponding projected ranges being widely spaced. At the same time, the thermal budget available for activating the hydrogen-related donors (HDs) can be limited, on the one hand due to the thermal stability of the precursor species, and on the other hand due to the thermal stability of the processed first surface, e.g., the wafer front (see, for example, process feature M10). This can lead to the regions between the implantation peaks sometimes not being adequately supplied with hydrogen (H), in which case insufficient n-doping can develop, which in extreme cases can even lead to a flip to a p-doped region. This undesirable effect can be counteracted by using plasma-based ion implantation, a comparatively cost-effective high-dose implantation method with first dopants consisting of a complex of the second dopant atom with hydrogen atoms. These hydrogen atoms, thus provided, can enhance the desired doping effect of the proton implantation. In the case of boron-doped semiconductor regions such as emitters, a complex of B₂H₆ can be selected as the process gas, for example, and for n-doped semiconductor regions such as emitters or contact areas, a complex of PH₃ or AsH₃ can be used as the process gas. In the following, the complexes are abbreviated as YHx, insofar as the statement applies to all complexes. In addition to the second dopant atom designated Y, another atom Z or further atoms, e.g., fluorine (F) or chromium (Cr), can also be present in the complex. During plasma-based ion implantation, the original process gas is ionized in a plasma above the semiconductor wafer, forming, for example, a complex YHx-1+, which is accelerated from the plasma onto the semiconductor wafer by a controlled voltage. Upon impact with the semiconductor wafer and interaction with its lattice atoms, the complex dissociates, leaving the doping species Y (e.g., B, P, As) and hydrogen radicals H in the wafer. Thus, a co-implantation of the doping species, i.e., the second dopant of process feature M30, and hydrogen atoms takes place. The doping species is used, for example, to form an n- or p-doped semiconductor region, such as a backside contact or backside emitter. The co-implantation of hydrogen atoms contributes to improved activation of the doping in the semiconductor region produced by proton implantation using process feature M20, e.g., a field stop zone. For a multi-stage proton-induced field stop zone, it is advantageous, for instance, to convert the p-doped region located between the end-ofranges of the individual proton peaks into an n-doped region in order to avoid undesired pn junctions, which can lead to increased leakage currents and conduction losses. This requires a sufficient concentration of hydrogen atoms, which are introduced into these regions, for example, by diffusion.Since plasma-based ion implantation provides a sufficiently high number of hydrogen atoms, the proton implantation dose can be reduced, particularly for the shallowest peak of a field stop zone, thus lowering proton implantation costs. Because the plasma-based ion implantation of the complex in process feature M30, for example, occurs at comparatively low implantation energies, e.g., between 1 keV and 30 keV, this implantation method, in addition to the improved activation of the proton doping described above in process feature M20, also achieves good ohmic contact by providing the second dopant atoms, which may, for example, be only partially activated. According to one embodiment, the method further comprises thinning the semiconductor body from the second surface after the introduction of the first dopant through the first surface and before the introduction of the second dopant. The semiconductor body can be thinned, for example, by 5% to 95% of its original thickness. According to one embodiment, the thinning includes mechanical thinning, e.g., grinding, polishing, lapping, or a combination thereof. During the thinning process, the semiconductor substrate, e.g., a wafer, can first be deposited onto a suitable support wafer to ensure sufficient mechanical stability during thinning. The mechanical thinning by grinding can, for example, initially be performed as coarse grinding at high speed in the range of one to several hundred µm / min, followed by fine grinding at a comparatively lower speed in the range of one to several tens of µm / min.According to another embodiment, mechanical thinning is followed by etching of the semiconductor body. This reduces defects and stresses in the semiconductor body caused by grinding, which can impair mechanical stability. Etching can be performed, for example, using a chemical wet etching and / or dry etching process such as plasma-based dry etching (RIE, Reactive Ion Etching). Optional polishing to reduce surface roughness can follow. Finally, the support wafer can be removed. According to one embodiment, after the introduction of the second dopant, a thermal annealing process is carried out at temperatures in the range of 300 °C to 420 °C, or also in the range of 370 °C to 410 °C. According to one embodiment, the duration of the thermal annealing process is 10 minutes to 5 hours or between 30 minutes and 4 hours. The thermal annealing process serves to heal the crystal of the semiconductor body, e.g., silicon wafer, from damage caused by previous implantations, as well as to activate stationary and stable hydrogen-correlated donors. According to one embodiment, the thermal annealing process is the final thermal treatment of the semiconductor body, with a maximum temperature of 420 °C, before the semiconductor device is completed. Thus, for example, the formation of any doped regions within the semiconductor body is already completed by introducing the first dopants through the first surface. Likewise, the introduction and thermal activation of the first dopants through the second surface into the semiconductor body, e.g., the formation of a back-side emitter region of an IGBT, is already completed. According to one embodiment, the plasma-based ion implantation process for introducing the second dopant is downstream of all processes for introducing first dopants into the semiconductor body through the first surface. Consequently, the semiconductor regions to be formed in the semiconductor body via the first surface, e.g., a source region, a body region, a body contact region, are already formed before the second dopant is introduced into the semiconductor body through the second surface using the plasma-based ion implantation process. According to one embodiment, the semiconductor device is designed as an IGBT. The single or multiple proton implantations in process feature M20 serve, for example, to form a field stop zone between a drift zone and a backside emitter. According to one embodiment, the process gas contains B2H6. Thus, using process feature M30, boron as a doping species for the formation of a backside emitter and hydrogen atoms to improve the activation of the proton doping according to process feature M20 can, for example, be introduced into the semiconductor body by co-implantation. According to one embodiment, the semiconductor device is configured as an IGFET or a diode. The single or multiple proton implantations in process feature M20 serve, for example, to form a field stop zone between a drift zone and a backside contact of the IGFET or the diode. According to one embodiment, the process gas contains PH3 or AsH3. Thus, using process feature M30, for example, phosphorus or arsenic can be introduced into the semiconductor body as dopant species to form a backside contact, and hydrogen atoms to improve the activation of the proton doping from process feature M20 can be introduced by co-implantation. The described plasma-based ion implantation process can, of course, also provide for the implantation of complexes comprising other dopant atoms such as antimony, bismuth, aluminum, gallium, or indium. According to one embodiment, the implantation energy of the plasma-based ion implantation process is set between 0.5 keV and 30 keV, or in particular between 4 and 12 keV. Thus, the second dopant is introduced only near the surface of the semiconductor body at the second surface. According to one embodiment, the method comprises forming an n-doped field stop zone, wherein at least two proton implantations are performed at different implantation energies, and the implanted protons are thermally activated to become hydrogen-correlated donors. For example, two, three, four, or even five proton implantations are performed at different implantation energies. According to one embodiment, the proton implantations exhibit a decreasing implantation dose with increasing implantation energy, i.e., increasing penetration depth into the semiconductor body. This allows, for example, a desired field stop zone profile to be advantageously set in the direction of the drift zone. According to one embodiment, after the introduction of the second dopant using the plasma-based ion implantation method, a diffusion barrier is formed on the second surface. The diffusion barrier prevents or hinders the diffusion of hydrogen atoms, in particular, from the semiconductor body through the second surface and can consist of a material or material combination suitable for acting as a barrier to hydrogen atoms. Silicon nitride is an example of a diffusion barrier material. According to a further embodiment, an implantation mask is formed on the second surface before the second dopant is introduced using the plasma-based ion implantation process. This mask serves as the implantation mask for the plasma-based ion implantation process. Similarly, according to another embodiment, an implantation mask can be formed on the first surface. This mask serves as the implantation mask for a further plasma-based ion implantation process using a complex of a dopant and hydrogen as the process gas. This allows the dopant to be masked and introduced into the semiconductor body via the first surface, for example, to form source or body regions. The hydrogen introduced by co-implantation can, for example, be used to saturate interfacial states of oxides located on the first surface.The complex for plasma-based ion implantation through the first surface can, for example, also include fluorine and / or chlorine atoms. The above embodiments are further illustrated with reference to Figs. 2, 3, 4, 5 to 6. With reference to the schematic cross-sectional view of Fig. 2, the introduction of a first dopant into a semiconductor body 102, as described, for example, in connection with process feature M10 of Fig. 1, is illustrated by way of example. The introduction of the first dopant is schematically indicated by arrows in Fig. 2. The information given in connection with the above embodiments regarding process feature M10 applies accordingly. For example, the semiconductor body can be thinned from a second surface 106, which leads to a reduction in the thickness d of the semiconductor body 102. With reference to the schematic cross-sectional view of Fig. 3, the execution of one or more proton implantations through the second surface 106 of the semiconductor body 102, opposite the first surface 104, as described, for example, in connection with process feature M20 of Fig. 1, is illustrated by way of example. The one or more proton implantations are schematically indicated by arrows in Fig. 3, and a concentration profile of hydrogen (H) resulting after implantation along a vertical direction y is schematically illustrated in the right part of Fig. 3 using two proton implantations of different energies. Of course, more than two proton implantations at different energies can also be carried out. A simplified representation of a device 110 for performing plasma-based ion implantation, as described, for example, in connection with process feature M30, is shown schematically in Fig. 4. The device 110 can be, for example, a process chamber or a reactor. The doping process is described using phosphorus as an example. Accelerating electrons into a plasma 111 causes bonds of the complexes in the plasma 111 to break. The dopant species accelerated onto the semiconductor body 102 can be changed by the length of the accelerating voltage pulse—and thus the length of the electron bombardment of the plasma 111. With very short pulses, for example, predominantly or exclusively H+ is deposited onto the semiconductor body 102, since H+ has the lowest inertia relative to the second dopant ions in the plasma. Thus, the length orThe ratio between introduced hydrogen and conventional dopants – phosphorus in the illustrated example – is adjusted by a sequence of successive pulses, depending on the application. The semiconductor body 102 is fixed to a substrate support 114, e.g., a wafer chuck. An acceleration source is simplified by being denoted by a "+" relative to the grounded substrate support 114. The co-doping of the method is explained by way of example using the activation of a field stop profile with reference to the diagram shown in Fig. 5. Hydrogen introduced near the surface by plasma-based ion implantation using process feature M30 according to the embodiment in Fig. 1 is shown as curve cH0. The profile broadened after thermal curing is shown as curve cH1. The introduced hydrogen leads to improved activation of hydrogen-correlated donors and, in particular, to the avoidance of undesirable p-doped zones between the proton-induced field stop peaks. This is illustrated by the dopant profiles cFS0 and cFS1 of a field stop zone. The dopant concentration profile cFS0 results from two proton implantations at different energies, as described, for example, in process feature M20, but without the use of process feature M30.However, the process feature M30, due to the additional hydrogen input, leads to improved activation of hydrogen-correlated donors, particularly in region B between peaks P0 and P1 of the field stop zone. This allows for a substantially constant dopant concentration in region B between peaks P0 and P1 in the illustrated example. The lower proton peaks, such as peak P1, whose crystal damage significantly defines the doping level, can remain unchanged and be adjusted as usual to adapt the vertical field stop doping profile. Since the dose of the lower peaks (e.g., peak P1 in Fig. 5) is generally lower than that of the shallower peak (e.g., peak P0 in Fig. 5), the required implantation time and thus the associated costs are not significant.Since plasma-based ion implantation according to process feature M30 provides a sufficiently high number of hydrogen atoms, the proton implantation dose can be reduced, especially for the flattest peak, cf. e.g. peak P0 in Fig. 5, and thus the proton implantation costs can be advantageously reduced. With reference to the schematic cross-sectional view of Fig. 6, an embodiment of a semiconductor device 101 is explained, which can be manufactured, for example, using the method according to Fig. 1. The semiconductor device 101 comprises a drift zone 116 of a first conductivity type in the semiconductor body 102, which has opposing first and second surfaces 104, 106. The semiconductor device 101 also comprises a doped field-stop zone 118 of a first conductivity type between the drift zone 116 and the second surface 106, wherein the field-stop zone 118, as illustrated, for example, by the concentration profile cFS1 in Fig. 5, has a dopant concentration peak P0 located at a vertical distance l from the second surface 106. A hydrogen concentration decreases along the vertical direction y from the second surface 106 over a length of at least 25% of the vertical distance l, cf., for example, the hydrogen concentration profile cH1 in the region 0.25xl in Fig. 5. The further details given in connection with the above embodiments, e.g.The first and second load connections L1, L2 and an optional control connection C, which depends on the component type, can be transferred to the embodiment in Fig. 6. Depending on the type of semiconductor component, a component head 119 can have different characteristics in a region of the semiconductor body adjacent to the first surface 104. A doped semiconductor region 120, e.g., a contact region or a back-side emitter, borders the second surface 106. The first conductivity type can, for example, be an n-type or a p-type. According to one embodiment, the semiconductor device 101 is a power semiconductor device configured to carry a load current of more than 1A between the first load terminal L1 and the second load terminal L2. According to one embodiment, the semiconductor device 101 has a doped semiconductor region adjacent to the second surface 106, e.g., the doped semiconductor region 120 shown in Fig. 6. According to this embodiment, the dopant concentration of a dopant species in the doped semiconductor region 120 decreases along the vertical direction y, and the dose of the dopant species resulting from the two-order-of-magnitude decrease in the dopant concentration along the vertical direction y is x times a hydrogen dose resulting from the two-order-of-magnitude decrease in the hydrogen concentration along the vertical direction y, where x is an integer greater than one. The correlation in the doses is due to the fact that, in plasma-based ion implantation with complexes (see, e.g., Fig. 4), hydrogen is present as an integer multiple of the introduced dopant species.

Claims

A method for manufacturing a semiconductor device comprising: introducing at least one first dopant into a semiconductor body (102) through a first surface (104) of the semiconductor body (102); and subsequently performing one or more proton implantations; introducing a second dopant into the semiconductor body (102) through the second surface (106) using a plasma-based ion implantation method, wherein the plasma-based ion implantation method is carried out with a complex of the second dopant and hydrogen as the process gas, and hydrogen of the complex is introduced into the semiconductor body (102) through the second surface (106) in addition to the second dopant, wherein the hydrogen is introduced into the semiconductor body in addition to the one or more proton implantations; and activating hydrogen-correlated donors. The method according to claim 1, further comprising: after the introduction of the at least one first dopant through the first surface (104) and before the introduction of the second dopant, thinning of the semiconductor body from the second surface (106). Method according to claim 2, wherein the thinning comprises mechanical thinning. Method according to claim 3, wherein after mechanical thinning a thinning is carried out by etching the semiconductor body (102). Method according to one of the preceding claims, wherein a thermal curing process is carried out at temperatures in the range of 300°C to 420°C to activate the hydrogen-correlated donors after the introduction of the second dopant. Method according to claim 5, wherein the duration of the thermal healing process is 10 minutes to 5 hours. Method according to one of claims 5 or 6, wherein the thermal curing process is the final thermal treatment of the semiconductor body (102) at a maximum temperature of 420°C before completion of the semiconductor device. Method according to one of the preceding claims, wherein the plasma-based ion implantation method for introducing the second dopant is downstream of all processes for introducing the at least first dopant materials into the semiconductor body (102) through the first surface (104). Method according to one of the preceding claims, wherein the semiconductor device is an IGBT, Insulated Gate Bipolar Transistor. Method according to one of the preceding claims, wherein the process gas comprises B2H6. Method according to any one of claims 1 to 8, wherein the semiconductor device is an IGFET, Insulated Gate Field Effect Transistor or a diode. Method according to one of claims 1 to 8 or 11, wherein the process gas comprises at least one PH3 or AsH3. Method according to one of the preceding claims, wherein the implantation energy of the plasma-based ion implantation method is set between 0.5 keV and 30 keV. A method according to one of the preceding claims, further comprising: forming an n-doped field stop zone (118), wherein at least two proton implantations are carried out at different implantation energies, and the implanted protons are thermally activated to become hydrogen-correlated donors. Method according to one of the preceding claims, wherein after the introduction of the second dopant using the plasma-based ion implantation method a diffusion barrier is formed on the second surface (106). Method according to one of the preceding claims, wherein, prior to the introduction of the second dopants using the plasma-based ion implantation method, an implantation mask is formed on the second surface (106), which serves as an implantation mask for the plasma-based ion implantation method.

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