A method for manufacturing a silicon carbide semiconductor device, includes the steps of preparing a silicon carbide substrate, depositing an insulating film on one principal surface of the silicon carbide substrate, forming a contact hole in the insulating film, and exposing the one principal surface at a bottom surface of the contact hole, forming a Si film on the bottom surface and a side surface of the contact hole, and a top surface of the insulating film, removing the Si film on the bottom surface of the contact hole, and exposing the one principal surface, depositing a Ni film on the bottom surface of the contact hole, and the Si film, and performing a heat treatment after depositing the Ni film, wherein the heat treatment forms a first alloy layer, which becomes an ohmic electrode, at the bottom surface of the contact hole by Si included in the silicon carbide substrate and the Ni film, and forms a second alloy layer at the top surface of the insulating film by the Si film and the Ni film.

A device for detecting UV radiation, comprising: a SiC substrate having an N doping; a SiC drift layer having an N doping, which extends over the substrate; a cathode terminal; and an anode terminal. The anode terminal comprises: a doped anode region having a P doping, which extends in the drift layer; and an ohmic-contact region including one or more carbon-rich layers, in particular graphene and/or graphite layers, which extends in the doped anode region. The ohmic-contact region is transparent to the UV radiation to be detected.

An SBD of a JBS structure has on a front side of a semiconductor substrate, nickel silicide films in ohmic contact with p-type regions and a FLR, and a titanium film forming a Schottky junction with an n.sup.−-type drift region. A thickness of each of the nickel silicide films is in a range from 300 nm to 700 nm. The nickel silicide films each has a first portion protruding from the front surface of the semiconductor substrate in a direction away from the front surface of the semiconductor substrate, and a second portion protruding in the semiconductor substrate from the front surface of the semiconductor substrate in a depth direction. A thickness of the first portion is equal to a thickness of the second portion. A width of the second portion is wider than a width of the first portion.

A semiconductor device includes a semiconductor layer made of SiC. A transistor element having an impurity region is formed in a front surface portion of the semiconductor layer. A first contact wiring is formed on a back surface portion of the semiconductor layer, and defines one electrode electrically connected to the transistor element. The first contact wiring has a first wiring layer forming an ohmic contact with the semiconductor layer without a silicide contact and a second wiring layer formed on the first wiring layer and having a resistivity lower than that of the first wiring layer.

Contact structures for semiconductor devices are disclosed. Contact structures that include a metal layer and a substrate of a semiconductor device may be annealed to provide suitable contact resistance. Localized annealed regions may be formed in a pattern within the contact structure to provide a desired contact resistance while reducing exposure of other portions of the semiconductor device to anneal conditions. The annealed regions may be formed in patterns that reduce intersections between annealed regions and fracture planes of the substrate, thereby improving mechanical robustness of the semiconductor device. The patterns may include annealed regions formed in lines that are nonparallel with fracture planes of the substrate. The patterns may also include annealed regions formed in lines that are nonparallel with peripheral edges of the substrate.

A method for producing a silicon carbide semiconductor device includes a step of preparing a silicon carbide substrate, a step of forming an insulating film on one main surface of the silicon carbide substrate, a step of forming a contact hole in the insulating film and exposing the one main surface of the silicon carbide substrate at a bottom surface of the contact hole, a step of forming an Si film on the bottom surface of the contact hole, a step of forming an Ni film on the Si film, a step of performing a first heat treatment at a first temperature at which Ni and Si react, after the step of forming the Ni film, a step of removing an unreacted portion of the Ni film that does not react with the Si film by wet etching after the first heat treatment, and a step of performing a second heat treatment at a second temperature higher than the first temperature after the step of removing the unreacted portion.

A silicon carbide device includes a silicon carbide substrate, a contact layer including nickel, silicon and aluminum, a barrier layer structure including titanium and tungsten, and a metallization layer including copper. The contact layer is located on the silicon carbide substrate. The contact layer is located between the silicon carbide substrate and at least a part of the barrier layer structure. The barrier layer structure is located between the silicon carbide substrate and the metallization layer.

An SiC semiconductor device includes an SiC chip having a first main surface at one side and a second main surface at another side, a first main surface electrode including a first Al layer and formed on the first main surface, a pad electrode formed on the first main surface electrode and to be connected to a lead wire, and a second main surface electrode including a second Al layer and formed on the second main surface.

A semiconductor device of an embodiment includes: a silicon carbide layer including a first silicon carbide region of n-type containing one metal element selected from a group consisting of nickel (Ni), palladium (Pd), platinum (Pt), and chromium (Cr) and a second silicon carbide region of p-type containing the metal element; and a metal layer electrically connected to the first silicon carbide region and the second silicon carbide region. Among the metal elements contained in the first silicon carbide region, a proportion of the metal element positioned at a carbon site is higher than a proportion of the metal element positioned at an interstitial position. Among the metal elements contained in the second silicon carbide region, a proportion of the metal element positioned at an interstitial position is higher than a proportion of the metal element positioned at a carbon site.

A method for manufacturing a semiconductor device includes: providing a semiconductor substrate having first and second sides; forming at least one doping region at the first side; forming a first metallization structure at the first side on and in contact with the at least one doping region; and subsequently forming a second metallization structure at the second side, the second metallization structure forming at least one silicide interface region with the semiconductor substrate and at least one non-silicide interface region with the semiconductor substrate.