The present disclosure relates to a semiconductor device with a contact structure and a method for preparing the semiconductor device. The semiconductor device includes a source/drain structure disposed over a semiconductor substrate, and a dielectric layer disposed over the source/drain structure. The semiconductor device also includes a polysilicon stack disposed over the source/drain structure and surrounded by the dielectric layer. The polysilicon stack includes a first polysilicon layer and a second polysilicon layer disposed over the first polysilicon layer. The first polysilicon layer is undoped, and the second polysilicon layer is doped. The semiconductor device further includes a contact structure disposed directly over the polysilicon stack and surrounded by the dielectric layer.

A power SiC MOSFET with a built-in Schottky rectifier provides advantages of including a Schottky rectifier, such as avoiding bipolar degradation, while reducing a parasitic capacitive charge and related power losses, as well as system cost. A lateral built-in channel layer may enable lateral spacing of the MOSFET gate oxide from a high electric field at the Schottky contact, while also providing current limiting during short-circuit events.

An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor.

A method for forming a semiconductor device includes: forming, in a silicon carbide layer of a first conductivity type having a first side, a first silicon carbide region and a second silicon carbide region that forms a pn-junction with the first silicon carbide region; forming a contact region that forms an Ohmic contact with the second silicon carbide region; forming a barrier-layer on the contact region and the first silicon carbide region so that a Schottky-junction is formed between the barrier-layer and the first silicon carbide region and so that an Ohmic connection is formed between the barrier-layer and the contact region, the barrier-layer comprising molybdenum nitride; and forming a first metallization on the barrier-layer, and in Ohmic connection with the barrier-layer.

An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor.

An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor.

An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor.

A method for forming a semiconductor device includes: forming, in a silicon carbide layer of a first conductivity type having a first side, a first silicon carbide region and a second silicon carbide region that forms a pn-junction with the first silicon carbide region; forming a contact region that forms an Ohmic contact with the second silicon carbide region; forming a barrier-layer on the contact region and the first silicon carbide region so that a Schottky-junction is formed between the barrier-layer and the first silicon carbide region and so that an Ohmic connection is formed between the barrier-layer and the contact region, the barrier-layer comprising molybdenum nitride; and forming a first metallization on the barrier-layer, and in Ohmic connection with the barrier-layer.

A charge balance (CB) field-effect transistor (FET) device may include a CB layer defined in a first epitaxial (epi) layer having a first conductivity type. The CB layer may include a set of CB regions having a second conductivity type. The CB FET device may further include a device layer defined in a device epi layer having the first conductivity type disposed on the CB layer. The device layer may include a highly-doped region having the second conductivity type. The CB FET device may also include a CB bus region having the second conductivity type that extends between and electrically couples a CB region of the set of CB regions of the CB layer to the highly-doped region of the device layer.

A semiconductor device includes a semiconductor body having a first silicon carbide region and a second silicon carbide region which forms a pn-junction with the first silicon carbide region, a first metallization on a front side of the semiconductor body, a contact region that forms an Ohmic contact with the second silicon carbide region, and a barrier-layer between the first metallization and the contact region and that is in Ohmic connection with the first metallization and the contact region. The barrier-layer forms a Schottky-junction with the first silicon carbide region, and includes molybdenum nitride or tantalum nitride. Additional semiconductor device embodiments and corresponding methods of manufacture are described.