Abstract: The embodiments relate to a method for producing a solar cell having a rear-side contact with a tunnel barrier. A monocrystalline wafer having a front side and a rear side may be provided with silicon and a dopant. A tunnel barrier is produced on the wafer, and a polycrystalline or amorphous layer is deposited on the tunnel barrier. The polycrystalline or amorphous layer includes silicon and a dopant. The polycrystalline or amorphous layer is removed on the front side by gas-phase etching.

Abstract: A sealing unit for a turbocharger for sealing a transition from a bearing housing into a compressor housing, and a method for producing a sealing unit of this type. The sealing unit includes a sealing bush which is designed for common rotation with a shaft of a turbocharger, a slide ring, and first and second groove rings. The first and second groove rings are designed for common rotation with the sealing bush and are arranged on the sealing bush. The slide ring is arranged between the first and second groove rings in the axial direction so that radially extending sealing gaps are formed on both sides of the slide ring between the slide ring and the respective groove ring.

Abstract: A sealing unit for a turbocharger for sealing a transition from a bearing housing into a compressor housing, and a method for producing a sealing unit of this type. The sealing unit includes comprises a sealing bush which is designed for common rotation with a shaft of a turbocharger, a slide ring, and first and second groove rings. The first and second, wherein the two groove rings are designed for common rotation with the sealing bush and are arranged on the sealing bush. The slide ring is arranged between the first and second two groove rings in the axial direction so that radially extending sealing gaps are formed on both sides of the slide ring between the slide ring and the respective groove ring.

Abstract: A regulating flap arrangement (1) of an exhaust-gas turbocharger (3) having a flap shaft (5), which is guided by means of a bushing (10) in the turbine housing (2). A shaped sealing ring (13), as viewed in cross section, has at least one cavity (14). The shaped sealing ring (13) bears simultaneously against the first sealing surface (11) and against the second sealing surface (12), and in order to impart its sealing action, is compressed and deformed in the axial direction (15) of the flap shaft (5).

Abstract: An exhaust-gas turbocharger (1) with a bearing housing (2), a shaft (3) mounted in the bearing housing (2), a compressor wheel (5) arranged on the shaft (3) and a turbine wheel (4) arranged on the shaft (3), a housing component (7) which surrounds the compressor wheel (5) or the turbine wheel (4), and a sealing ring (14) between the bearing housing (2) and the housing component (7), wherein the sealing ring (14) is, in order to impart its sealing action, compressed in a direction perpendicular to the shaft (3).

Abstract: A regulating flap arrangement (1) of an exhaust-gas turbocharger (3) having a flap shaft (5), which is guided by means of a bushing (10) in the turbine housing (2). A shaped sealing ring (13), as viewed in cross section, has at least one cavity (14). The shaped sealing ring (13) bears simultaneously against the first sealing surface (11) and against the second sealing surface (12), and in order to impart its sealing action, is compressed and deformed in the axial direction (15) of the flap shaft (5).

Abstract: A method for producing a photovoltaic solar cell, including the following steps: A. texturizing a front (2) of a semiconductor substrate; B. generating a selective emitter doping on the front (2) of the semiconductor substrate by generating on the front (2) a first low-doped region (4) and a local high-doped region (3) within the first low-doped region; and C. applying at least one metal emitter contact structure to the front (2) of the semiconductor substrate, at least in the regions of local high doping, wherein, between method steps B and C, a respective silicon oxide layer (5a, 5b) is generated in a method step B1 simultaneously on the front and back of the semiconductor substrate via thermal oxidation.

Abstract: An exhaust-gas turbocharger (1) with a bearing housing (2), a shaft (3) mounted in the bearing housing (2), a compressor wheel (5) arranged on the shaft (3) and a turbine wheel (4) arranged on the shaft (3), a housing component (7) which surrounds the compressor wheel (5) or the turbine wheel (4), and a sealing ring (14) between the bearing housing (2) and the housing component (7), wherein the sealing ring (14) is, in order to impart its sealing action, compressed in a direction perpendicular to the shaft (3).

Abstract: A method for producing a selective doping structure in a semiconductor substrate in order produce a photovoltaic solar cell. The method includes the following steps: A) applying a doping layer (2) to the emitter side of the semiconductor substrate, B) locally heating a melting region of the doping layer (2) and a melting region of the semiconductor substrate lying under the doping layer (2) in such a way that dopant diffuses from the doping layer (2) into the melted semiconductor substrate via liquid-liquid diffusion, so that a high doping region (3) is produced after the melt mixture solidifies, C) producing the planar low doping region by globally heating the semiconductor substrate, D) removing the doping layer (2) and E) removing or converting a layer of the semiconductor substrate on the doping side in such a way that part of the low doping region and of the high doping region close to the surface is removed or is converted into an electrically non-conducting layer.

Abstract: A method for producing a selective doping structure in a semiconductor substrate in order produce a photovoltaic solar cell. The method includes the following steps: A) applying a doping layer (2) to the emitter side of the semiconductor substrate, B) locally heating a melting region of the doping layer (2) and a melting region of the semiconductor substrate lying under the doping layer (2) in such a way that dopant diffuses from the doping layer (2) into the melted semiconductor substrate via liquid-liquid diffusion, so that a high doping region (3) is produced after the melt mixture solidifies, C) producing the planar low doping region by globally heating the semiconductor substrate, D) removing the doping layer (2) and E) removing or converting a layer of the semiconductor substrate on the doping side in such a way that part of the low doping region and of the high doping region close to the surface is removed or is converted into an electrically non-conducting layer.

Abstract: A method for producing a photovoltaic solar cell, including the following steps: A. texturizing a front (2) of a semiconductor substrate; B. generating a selective emitter doping on the front (2) of the semiconductor substrate by generating on the front (2) a first low-doped region (4) and a local high-doped region (3) within the first low-doped region; and C. applying at least one metal emitter contact structure to the front (2) of the semiconductor substrate, at least in the regions of local high doping, wherein, between method steps B and C, a respective silicon oxide layer (5a, 5b) is generated in a method step B1 simultaneously on the front and back of the semiconductor substrate via thermal oxidation.

Abstract: A method for producing a solar cell from a silicon wafer, including the following process steps: A) texturizing one side of the silicon substrate (1) for improving the absorption or removing saw damage on one side of the silicon substrate (1); B) generating an emitter area (2) on one side of the silicon substrate (1) by diffusing in a doping material for forming a pn transition; C) removing a glass layer which comprises the doping material; D) applying a masking layer (3) which is a dielectric layer; E) removing one part of the material of the silicon substrate (1); F) applying metal structures (5, 6) for electrically contacting the solar cell. It is significant that thermal oxidation is performed between the process steps E and F for forming an oxide layer (4) and that the masking layer (3) and the oxide layer (4) remain on the silicon substrate (1) in the subsequent process steps.