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.

A bipolar transistor includes a collector layer, a base layer, and an emitter layer that are formed in this order on a compound semiconductor substrate. The emitter layer is disposed inside an edge of the base layer in plan view. A base electrode is disposed on partial regions of the emitter layer and the base layer so as to extend from an inside of the emitter layer to an outside of the base layer in plan view. An insulating film is disposed between the base electrode and a portion of the base layer, with the portion not overlapping the emitter layer. An alloy layer extends from the base electrode through the emitter layer in a thickness direction and reaches the base layer. The alloy layer contains at least one element constituting the base electrode and elements constituting the emitter layer and the base layer.

A device includes a substrate, a first well doped with dopants of a first conductivity type defined in the substrate, and a second well doped with dopants of a second conductivity type different than the first conductivity type defined in the substrate adjacent the first well to define a PN junction. The second well includes a silicon alloy portion displaced from the PN junction. A collector region contacts one of the first or second wells and has a dopant concentration higher than its contacted well. An emitter region contacts the other of the first or second wells and is doped with dopants of the first or second conductivity type different than the first or second well contacted by the emitter region. A base region contacts the other of the first or second well and has a dopant concentration higher than the first or second well contacted by the base region.

A semiconductor device includes a single semiconductor substrate on which an IGBT region including an IGBT element and an FWD region including a FWD element are formed. In the semiconductor device, a cathode layer is formed with a carrier injection layer, which is electrically connected to a second electrode and has a PN junction with a field stop layer. When a first carrier in the FWD element passes through the field stop layer on the carrier injection layer and flows into the cathode layer in a situation where a forward-biased current is cut off from a state in which the forward-biased current is flowing through the FWD element, a second carrier is injected from the second electrode into a drift layer through the carrier injection layer.

Thermally-sensitive structure and methods for sensing the temperature in a region of a bipolar junction transistor (BJT) during device operation are described. The region may be at or near a region of highest temperature attained in the BJT. Metal resistance thermometry (MRT) can be implemented to assess a peak operating temperature of a BJT.

Structures for a cascode integrated circuit and methods of forming such structures. A field-effect transistor of the structure includes a gate electrode finger, a first source/drain region, and a second source/drain region. A bipolar junction transistor of the structure includes a first terminal, a base layer with an intrinsic base portion arranged on the first terminal, and a second terminal that includes one or more fingers arranged on the intrinsic base portion of the base layer. The intrinsic base portion of the base layer is arranged in a vertical direction between the first terminal and the second terminal. The first source/drain region is coupled with the first terminal, and the first source/drain region at least partially surrounds the bipolar junction transistor.

A bipolar junction transistor having a relatively reduced size and an improved current gain and a method of manufacturing the same are disclosed. The bipolar junction transistor includes a plurality of emitter regions disposed in a substrate, a plurality of base regions disposed in the substrate and configured to surround the emitter regions, respectively, and a collector region disposed in the substrate and configured to surround the base regions. The plurality of emitter and base regions may be arranged in a matrix.

On a single-crystal semiconductor substrate with an upper surface including a first direction in which an inverted mesa step extends and a second direction in which a forward mesa step extends in response to anisotropic etching in which an etching rate depends on crystal plane orientation, a bipolar transistor including a collector layer, a base layer, and an emitter layer that are epitaxially grown, and a base wire connected to the base layer are arranged. A step is provided at an edge of the base layer, and the base wire is extended from inside to outside of the base layer in a direction intersecting the first direction in a plan view. An intersection of the edge of the base layer and the base wire has a disconnection prevention structure that makes it difficult for step-caused disconnection of the base wire to occur.

A device includes a substrate, a first well doped with dopants of a first conductivity type defined in the substrate, and a second well doped with dopants of a second conductivity type different than the first conductivity type defined in the substrate adjacent the first well to define a PN junction. The second well includes a silicon alloy portion displaced from the PN junction. A collector region contacts one of the first or second wells and has a dopant concentration higher than its contacted well. An emitter region contacts the other of the first or second wells and is doped with dopants of the first or second conductivity type different than the first or second well contacted by the emitter region. A base region contacts the other of the first or second well and has a dopant concentration higher than the first or second well contacted by the base region.

It is prevented that when a predetermined number of semiconductor chips having transistors are manufactured from one semiconductor wafer, manufacturing cost of a semiconductor device is increased due to excess semiconductor chips manufactured from the semiconductor wafer. A first bipolar transistor including a first emitter region having a first area is formed in a first chip formation region in an exposure region that can be exposed by one exposure step, and a second bipolar transistor including a second emitter region having a second area different from the first area is formed in a second chip formation region in the exposure region.