A method for manufacturing an epitaxial wafer comprising a silicon carbide substrate and a silicon carbide voltage-blocking-layer, the method includes: epitaxially growing a buffer layer on the substrate, doping a main dopant for determining a conductivity type of the buffer layer and doping an auxiliary dopant for capturing minority carriers in the buffer layer at a doping concentration less than the doping concentration of the main dopant, so that the buffer layer enhances capturing and extinction of the minority carriers, the minority carriers flowing in a direction from the voltage-blocking-layer to the substrate, so that the buffer layer has a lower resistivity than the voltage-blocking-layer, and so that the buffer layer includes silicon carbide as a main component; and epitaxially growing the voltage-blocking-layer on the buffer layer.

A semiconductor device includes an anode doping region of a diode structure arranged in a semiconductor substrate. The anode doping region has a first conductivity type. The semiconductor device further includes a second conductivity type contact doping region having a second conductivity type. The second conductivity type contact doping region is arranged at a surface of the semiconductor substrate and surrounded in the semiconductor substrate by the anode doping region. The anode doping region includes a buried non-depletable portion. At least part of the buried non-depletable portion is located below the second conductivity type contact doping region in the semiconductor substrate.

A semiconductor device includes first and second pads separated from each other, first and second test elements connected to the first and second pads and connected to each other in parallel between the first and second pads, a first diode connected to the first test element in series, and a second diode connected to the second test element in series.

A semiconductor device includes first and second pads separated from each other, first and second test elements connected to the first and second pads and connected to each other in parallel between the first and second pads, a first diode connected to the first test element in series, and a second diode connected to the second test element in series.

A semiconductor device includes: an n− type layer disposed on a first surface of an n+ type silicon carbide substrate; a first trench and a second trench formed in the n− type layer and separated from each other; an n+ type region disposed between a side surface of the first trench and the side surface of the second trench and disposed on the n− type layer; a gate insulating layer disposed inside the first trench; a source insulating layer disposed inside the second trench; a gate electrode disposed on the gate insulating layer; an oxide layer disposed on the gate electrode; a source electrode disposed on the oxide layer, the n+ type region, and the source insulating layer; and a drain electrode disposed on a second surface of the n+ type silicon carbide substrate.

A terminal structure of a power device includes a substrate and a plurality of field limiting rings disposed on a first surface of the substrate. The substrate includes a drift layer and a doped layer. The doped layer is formed through diffusion inward from the first surface of the substrate. The doped layer and the drift layer are a first conductivity type, and an impurity concentration of the doped layer is greater than an impurity concentration of the drift layer. The field limiting rings are a second conductivity type. In the terminal structure, lateral diffusion of impurities in the field limiting rings is limited through a design of the doped layer.

A semiconductor device includes a cooling base board and an insulated circuit substrate. On a front surface of an insulated board on the insulated circuit substrate, a high potential circuit pattern on which a semiconductor chip is mounted, an intermediate potential circuit pattern on which a semiconductor chip is mounted, a low potential circuit pattern, and a control circuit pattern are disposed so as to straddle a center line of the cooling base board. The intermediate potential circuit pattern includes a second chip mounting region, an output wiring connection region and an interconnect wiring region that form a U-shaped portion in which the high potential circuit pattern having a semiconductor chip thereon is disposed. The control circuit pattern is disposed so as to straddle the center line and faces the opening of the U-shaped portion.

The present disclosure has an object of providing a silicon carbide semiconductor device with high productivity which prevents characteristic degradation occurring when a large current is applied to a body diode. A structure including a SiC substrate, a buffer layer, and a drift layer is classified into an active region through which a current flows with application of a voltage to the SiC-MOSFET, and a breakdown voltage support region around a periphery of the active region in a plan view. The active region is classified into a first active region in a center portion, and a second active region between the first active region and the breakdown voltage support region in the plan view. Lifetimes of minority carriers in the second active region and the breakdown voltage support region are shorter than that in the first active region.

An electrostatic discharge (ESD) protection device includes a first clamping circuit, a second clamping circuit, and a diode circuit. The first clamping circuit is coupled between a first power rail and a second power rail. The second clamping circuit is coupled between a third power rail and the second power rail. The diode circuit is configured to steer an ESD current from an input/output pad to at least one of the first clamping circuit or the third power rail. The first power rail receives a first voltage, the second power rail receives a second voltage, the third power rail receives a third voltage, the third voltage is higher than the first voltage, and the first voltage is higher than the second voltage.

An electrostatic discharge (ESD) protection device includes a first clamping circuit, a second clamping circuit, and a diode circuit. The first clamping circuit is coupled between a first power rail and a second power rail. The second clamping circuit is coupled between a third power rail and the second power rail. The diode circuit is configured to steer an ESD current from an input/output pad to at least one of the first clamping circuit or the third power rail. The first power rail receives a first voltage, the second power rail receives a second voltage, the third power rail receives a third voltage, the third voltage is higher than the first voltage, and the first voltage is higher than the second voltage.