Infineon Technologies Ag

Gerald Unegg

Romain Esteve

Ravi Keshav Joshi

Roland Rupp

Markus Kahn

Dethard Peters

Wolfgang Bergner

Thomas Aichinger

Juergen Steinbrenner

Daniel Kueck

Kurt Pekoll

Victorina Poenariu

Gerald Reinwald

Francisco Javier Santos Rodriguez

A semiconductor device includes a silicon carbide semiconductor body and a metal contact structure. Interface particles including a silicide kernel and a carbon cover on a surface of the silicide kernel are formed directly between the silicon carbide semiconductor body and the metal contact structure. Between neighboring ones of the interface particles, the metal contact structure directly adjoins the silicon carbide semiconductor body.

Forming a metal contact layer on silicon carbide and semiconductor device with metal contact structure

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.

Method of manufacturing a silicon carbide semiconductor device by removing amorphized portions

A silicon-carbide substrate that includes: a doped silicon-carbide contact region directly adjoining a main surface of the substrate, and a dielectric layer covering the main surface is provided. A protective layer is formed on the silicon-carbide substrate such that the protective layer covers the dielectric layer and exposes the doped silicon-carbide contact region at the main surface. A metal layer that conforms to the protective layer and directly contacts the exposed doped silicon-carbide contact region is deposited. A first rapid thermal anneal process is performed. A thermal budget of the first rapid thermal anneal process is selected to cause the metal layer to form a silicide with the doped silicon-carbide contact region during the first rapid thermal anneal process without causing the metal layer to form a silicide with the protective layer during the first rapid thermal anneal process.

Self aligned silicon carbide contact formation using protective layer

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.

Carbon based contact structure for silicon carbide device technical field

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.

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Villach, Austria

Gerald Unegg