A method forms a part of a power semiconductor device. The method includes homoepitaxially forming two silicon carbide layers on a first side of a silicon carbide substrate and forming a pattern of pits on a second side of the silicon carbide substrate. The two layers include a buffer layer, on the first side of the silicon carbide substrate, and have a same doping type of the silicon carbide substrate and a doping concentration equal to or greater than 10.sup.17 cm.sup.−3 in order to increase the quality of at least one subsequent SiC layer. The two layers include an etch stopper layer, being deposited on the buffer layer and has a same doping type as the buffer layer but a lower doping concentration in order to block a trenching process. The pattern of pits, obtained by electrochemical etching, extends completely thorough the silicon carbide substrate and the buffer layer.

A device for processing at least one semiconductor substrate. The device includes: a reactor with a wall which encloses a reaction chamber; a closing structure for loading the reaction chamber with at least one semiconductor substrate and for unloading the at least one semiconductor substrate from the reaction chamber and for hydrofluoric acid-tight closure of the reaction chamber; and a heating device designed to establish at least one specified temperature in at least one temperature range in the reaction chamber. The device further includes: a gas inlet designed to supply hydrofluoric acid in vapor form to the reaction chamber, and a gas outlet designed to remove hydrofluoric acid in vapor form from the reaction chamber; and a gas supply system which is coupled to the gas inlet and is designed to supply hydrofluoric acid in vapor form to the gas inlet at the specified temperature.

A semiconductor device includes a SiC substrate and a plurality of transistor cells formed in the SiC substrate and electrically connected in parallel to form a transistor. Each transistor cell includes a gate structure including a gate electrode and a gate dielectric stack separating the gate electrode from the SiC substrate. The gate dielectric stack includes a ferroelectric insulator. The transistor has a specified operating temperature range, and the ferroelectric insulator is doped with a doping material such that the Curie temperature of the ferroelectric insulator is in a range above the specified operating temperature range of the transistor. A corresponding method of producing the semiconductor device is also described.

Aspects of the disclosure provide a method of forming a semiconductor apparatus including a first portion and a second portion. The first portion is formed on a first substrate and includes at least one first semiconductor device. The second portion is formed on a second substrate including a bulk substrate material and includes at least one second semiconductor device. A carrier substrate is attached to the second portion. The bulk substrate material is removed from the second substrate. The first portion and the second portion are bonded to form the semiconductor apparatus where the at least one second semiconductor device is stacked above the at least one first semiconductor device along a Z direction substantially perpendicular to a substrate plane of the first substrate. The at least one first semiconductor device and the at least one second semiconductor device are positioned between the carrier substrate and the first substrate.

A semiconductor device has a substrate. The substrate can be multiple layers. A first semiconductor layer made of a first semiconductor material is disposed over the substrate. The first semiconductor material can be substantially defect-free silicon carbide. A second semiconductor layer made of a second semiconductor material dissimilar from the first semiconductor material is disposed over the first semiconductor layer. The second semiconductor material is silicon. A third layer can be disposed between the first semiconductor layer and second semiconductor layer. A semiconductor device is formed in the second semiconductor layer. The semiconductor device can be a power MOSFET or diode. The second semiconductor layer with the electrical component provides a first portion of a breakdown voltage for the semiconductor device and the first semiconductor layer and substrate provide a second portion of the breakdown voltage for the semiconductor device.

A manufacturing method of an electrochemical sensor comprises forming a graphene layer on a donor substrate, laminating a film of dry photoresist on the graphene layer, removing the donor substrate to obtain an intermediate structure comprising the film of dry photoresist and the graphene layer, and laminating the intermediate structure onto a final substrate with the graphene layer in electrical contact with first and second electrodes positioned on the final substrate. The film of dry photoresist is then patterned to form a microfluidic structure on the graphene layer and an additional dry photoresist layer is laminated over the structure. In one type of sensor manufactured by this process, the graphene layer acts as a channel region of a field-effect transistor, whose conductive properties vary according to characteristics of an analyte introduced into the microfluidic structure.

In a step of calculating formation conditions for the second silicon carbide layer, a formation time of the second silicon carbide layer is calculated as a value obtained by multiplying a value obtained by dividing the second thickness by the first thickness, by the first formation time, and a flow rate of a second ammonia gas in a step of forming the second silicon carbide layer by epitaxial growth is calculated as a value obtained by multiplying a value obtained by dividing the second concentration by the first concentration, by the first flow rate.

In a step of calculating formation conditions for the second silicon carbide layer, a formation time of the second silicon carbide layer is calculated as a value obtained by multiplying a value obtained by dividing the second thickness by the first thickness, by the first formation time, and a flow rate of a second ammonia gas in a step of forming the second silicon carbide layer by epitaxial growth is calculated as a value obtained by multiplying a value obtained by dividing the second concentration by the first concentration, by the first flow rate.

A method includes providing a layer of porous silicon carbide supported by a silicon carbide substrate, providing a layer of epitaxial silicon carbide on the layer of porous silicon carbide, forming a plurality of semiconductor devices in the layer of epitaxial silicon carbide, and separating the substrate from the layer of epitaxial silicon carbide at the layer of porous silicon carbide. Additional methods are described.

A semiconductor device includes a first electrode, a first semiconductor layer of a first conductivity type on the first electrode, a first pillar of a second conductivity type on the first semiconductor layer, the first pillar having a first average concentration of impurities, a second pillar of the first conductivity type on the first semiconductor layer, and including a first layer having a second average concentration of impurities lower than the first average concentration, and a second layer having a third average concentration of impurities higher than the first average concentration, a second semiconductor layer of the second conductivity type on the second pillar, a third semiconductor layer of the first conductivity type on the second semiconductor layer, a second electrode connected to the first pillar and the third semiconductor layer, a third electrode, and an insulating film disposed between the second semiconductor layer and the third electrode.