Abstract: A method of defect reduction for a SiC layer includes activating dopants disposed in the SiC layer, depositing a carbon-rich layer on the SiC layer after activating the dopants, tempering the carbon-rich layer so as to form graphite on the SiC layer, and diffusing carbon from the graphite into the SiC layer. Carbon diffused from the graphite fills carbon vacancies in the SiC layer.

Abstract: A method of forming a contact structure includes providing a silicon-carbide substrate having a highly doped silicon-carbide contact region formed in the substrate and extending to a main surface of the substrate. A carbon-based contact region is formed which is in direct contact with the highly doped silicon-carbide contact region and which extends to the main surface. A conductor is formed on the carbon-based contact region such that the carbon-based contact region is interposed between the conductor and the highly doped silicon-carbide contact region. A thermal budget for forming the carbon-based contact region is maintained below a level that induces metal silicidization of the highly doped silicon-carbide contact region.

Abstract: A semiconductor device includes trench gate structures in a semiconductor body with hexagonal crystal lattice. A mean surface plane of a first surface is tilted to a <1-100> crystal direction by an off-axis angle, wherein an absolute value of the off-axis angle is in a range from 2 degree to 12 degree. The trench gate structures extend oriented along the <1-100> crystal direction. Portions of the semiconductor body between neighboring trench gate structures form transistor mesas. Sidewalls of the transistor mesas deviate from a normal to the mean surface plane by not more than 5 degree.

Abstract: A silicon-carbide substrate that includes a doped contact region and a dielectric layer is provided. A protective layer is formed on the dielectric layer. A structured mask is formed on the protective layer. Sections of the protective layer and the dielectric layer that are exposed by openings in the mask are removed. The structured mask is removed. A metal layer is deposited such that a first portion of the metal layer directly contacts the doped contact region and a second portion of the metal layer lines the remaining sections of the protective layer and the dielectric layer. A first rapid thermal anneal process is performed. After performing the first rapid thermal anneal process, the second portion of the metal layer and the remaining section of the protective layer are removed without removing the first portion of the metal layer.

Abstract: A method of manufacturing a vertical junction field effect transistor (JFET) includes forming a drain in a semiconductor substrate, forming a compound semiconductor epitaxial layer on the semiconductor substrate, and forming a source, a gate, a drift region, and a body diode all in the same compound semiconductor epitaxial layer. The drain is vertically spaced apart from the source and the gate by the drift region. The body diode is connected between the drain and the source.

Abstract: A SIC transistor device includes a silicon-carbide semiconductor substrate having a plurality of first doped regions laterally spaced apart from one another and beneath a main surface of the substrate, a second doped region extending from the main surface to a third doped region that is above the first doped regions, and a plurality of fourth doped regions in the substrate extending from the main surface to the first doped regions. The second doped region has a first conductivity type. The first, third and fourth doped regions have a second conductivity type opposite the first conductivity type. A gate trench extends through the second and third doped regions. The gate trench has sidewalls, a bottom and rounded corners between the bottom and the sidewalls.

Abstract: A trench is formed that extends from a main surface into a crystalline silicon carbide semiconductor layer. A mask is formed that includes a mask opening exposing the trench and a rim section of the main surface around the trench. By irradiation with a particle beam a first portion of the semiconductor layer exposed by the mask opening and a second portion outside of the vertical projection of the mask opening and directly adjoining to the first portion are amorphized. A vertical extension of the amorphized second portion gradually decreases with increasing distance to the first portion. The amorphized first and second portions are removed.

Abstract: A beam modifier device is provided that includes scattering portions in which particles vertically impinging on an exposure surface of the beam modifier device are deflected from a vertical direction. A total permeability for the particles changes along a lateral direction parallel to the exposure surface.

Abstract: A silicon-carbide semiconductor substrate having a plurality of first doped regions being laterally spaced apart from one another and beneath a main surface, and a second doped region extending from the main surface to a third doped region that is above the first doped regions is formed. Fourth doped regions extending from the main surface to the first doped regions are formed. A gate trench having a bottom that is arranged over a portion of one of the first doped regions is formed. A high-temperature step is applied to the substrate so as to realign silicon-carbide atoms along sidewalls of the trench and form rounded corners in the gate trench. A surface layer that forms along the sidewalls of the gate trench during the high-temperature step from the substrate is removed.

Abstract: A transistor cell includes a drift region, a source region, and a body region arranged between the source region and the drift region in a semiconductor body. A drain region is below the drift region. An insulated gate trench extends into the drift region. A diode region extends deeper into the drift region than the insulated gate trench and partly under the insulated gate trench so as to form a pn junction with the drift region below a bottom of the insulated gate trench. The body region adjoins a first sidewall of the insulated gate trench and the diode region adjoins a second sidewall of the insulated gate trench opposite the first sidewall so that the body region of the transistor cell and a channel region including a region of the body region extending along the first sidewall are separated from the diode region by the insulated gate trench.

Abstract: A silicon-carbide semiconductor substrate having a plurality of first doped regions being laterally spaced apart from one another and beneath a main surface, and a second doped region extending from the main surface to a third doped region that is above the first doped regions is formed. Fourth doped regions extending from the main surface to the first doped regions are formed. A gate trench having a bottom that is arranged over a portion of one of the first doped regions is formed. A high-temperature step is applied to the substrate so as to realign silicon-carbide atoms along sidewalls of the trench and form rounded corners in the gate trench. A surface layer that forms along the sidewalls of the gate trench during the high-temperature step from the substrate is removed.

Abstract: A semiconductor device includes a semiconductor body and at least one device cell integrated in the semiconductor body. Each device cell includes: a drift region, a source region, and a body region arranged between the source and drift regions; a diode region and a pn junction between the diode and drift regions; a trench having a first sidewall, a second sidewall opposite the first sidewall, and a bottom, the body region adjoining the first sidewall, the diode region adjoining the second sidewall, and the pn junction adjoining the bottom; a gate electrode in the trench and dielectrically insulated from the body, diode and drift regions by a gate dielectric. The diode region has a lower diode region arranged below the trench bottom, and the lower diode region has a maximum of a doping concentration distant to the trench bottom. A corresponding method of manufacturing the device also is provided.

Abstract: A semiconductor device includes trench gate structures in a semiconductor body with hexagonal crystal lattice. A mean surface plane of a first surface is tilted to a <1-100> crystal direction by an off-axis angle, wherein an absolute value of the off-axis angle is in a range from 2 degree to 12 degree. The trench gate structures extend oriented along the <1-100> crystal direction. Portions of the semiconductor body between neighboring trench gate structures form transistor mesas. Sidewalls of the transistor mesas deviate from a normal to the mean surface plane by not more than 5 degree.

Abstract: A semiconductor device includes trench structures that extend from a first surface into a semiconductor body. The trench structures include a gate structure and a contact structure that extends through the gate structure, respectively. Transistor mesas are between the trench structures. Each transistor mesa includes a body zone forming a first pn junction with a drift structure and a second pn junction with a source zone. Diode regions directly adjoin one of the contact structures form a third pn junction with the drift structure, respectively.

Abstract: A semiconductor device includes a semiconductor body with a first main crystal direction parallel to a horizontal plane. Longitudinal axes of trench gate structures are tilted to the first main crystal direction by a tilt angle of at least 2 degree and at most 30 degree in the horizontal plane. Mesa portions are between neighboring trench gate structures. First sidewall sections of first mesa sidewalls are main crystal planes parallel to the first main crystal direction. Second sidewall sections tilted to the first sidewall sections connect the first sidewall sections.

Abstract: A semiconductor body has a drift region layer, a body region layer adjoining the drift region layer, and a source region layer adjoining the body region layer and forming a first surface of the semiconductor body. At least two diode regions extend from the first surface through the source and body region layers into the drift region layer. Each diode region and the drift region layer form one pn-junction. At least two trenches have first and second opposing sidewalls and a bottom such that each trench adjoins the body region layer on one sidewall, one diode region on the second sidewall and one pn-junction on the bottom. In each trench, a gate dielectric dielectrically insulates a gate electrode from the semiconductor body. Sections of the source and body region layers remaining after forming the diode regions form source regions and body regions, respectively.

Abstract: A silicon-carbide semiconductor substrate having a plurality of first doped regions being laterally spaced apart from one another and beneath a main surface, and a second doped region extending from the main surface to a third doped region that is above the first doped regions is formed. Fourth doped regions extending from the main surface to the first doped regions are formed. A gate trench having a bottom that is arranged over a portion of one of the first doped regions is formed. A high-temperature step is applied to the substrate so as to realign silicon-carbide atoms along sidewalls of the trench and form rounded corners in the gate trench. A surface layer that forms along the sidewalls of the gate trench during the high-temperature step from the substrate is removed.

Abstract: A semiconductor device includes a semiconductor body and a device cell in the semiconductor body. The device cell includes: drift, source, body and diode regions; a pn junction between the diode and drift regions; a trench with first and second opposing sidewalls and a bottom, the body region adjoining the first sidewall, the diode region adjoining the second sidewall, and the pn junction adjoining the trench bottom; a gate electrode in the trench and dielectrically insulated from the source, body, diode and drift regions by a gate dielectric; a further trench extending from a first surface of the semiconductor body into the semiconductor body; a source electrode arranged in the further trench adjoining the source and diode regions. The diode region includes a lower diode region arranged below the trench bottom. The lower diode region has a maximum of a doping concentration distant to the trench bottom.

Abstract: A semiconductor device includes at least two device cells integrated in a semiconductor body. Each device cell includes a drift region, a source region, a drain region arranged between the source region and the drift region, a diode region, a pn junction between the diode region and the drift region, and a trench with a first sidewall, a second sidewall opposite the first sidewall, and a bottom. The body region adjoins the first sidewall, the diode region adjoins the second sidewall, and the pn junction adjoins the bottom of the trench. Each device cell further includes a gate electrode arranged in the trench and dielectrically insulated from the body region, the diode region and the drift region by a gate dielectric. The diode regions of the at least two device cells are distant in a lateral direction of the semiconductor body.

Abstract: A method of manufacturing a vertical junction field effect transistor (JFET) includes forming a drain in a semiconductor substrate, forming a compound semiconductor epitaxial layer on the semiconductor substrate, and forming a source, a gate, a drift region, and a body diode all in the same compound semiconductor epitaxial layer. The drain is vertically spaced apart from the source and the gate by the drift region. The body diode is connected between the drain and the source.