Structures for a bipolar junction transistor and methods of fabricating a structure for a bipolar junction transistor. The structure includes a first base layer, a second base layer, a first terminal positioned between the first base layer and the second base layer, a second terminal, and a third terminal. The first base layer, the second base layer, and the first terminal are positioned between the second terminal and the third terminal. For example, the first terminal may be positioned in a vertical direction between the first and second base layers.

A power semiconductor device includes a semiconductor wafer, a thyristor structure, and a bipolar junction transistor. The thyristor structure includes a first emitter layer of a first conductivity type adjacent the first main side, a first base layer of a second conductivity type, a second base layer of the first conductivity type, a second emitter layer of the second conductivity type, a gate electrode, a first main electrode, and a second main electrode arranged. The bipolar junction transistor includes a base electrode electrically separated from the gate electrode, a third main electrode arranged on the first main side and a fourth main electrode arranged on the second main side. The first main electrode is electrically connected to the third main electrode and the second main electrode is electrically connected to the fourth main electrode.

A method includes forming a deep well region of a first conductivity type in a substrate, implanting a portion of the deep well region to form a first gate, and implanting the deep well region to form a well region. The well region and the first gate are of a second conductivity type opposite the first conductivity type. An implantation is performed to form a channel region of the first conductivity type over the first gate. A portion of the deep well region overlying the channel region is implanted to form a second gate of the second conductivity type. A source/drain implantation is performed to form a source region and a drain region of the first conductivity type on opposite sides of the second gate. The source and drain regions are connected to the channel region, and overlap the channel region and the first gate.

Vertical bipolar junction transistors (VBJTs), each with one or more resistors connected in a circuit in different circuit configurations, are disclosed. The VBJT has an emitter substructure that includes an emitter layer, a collector, an intrinsic base, one or more doped epitaxy regions, and one or more resistors. The intrinsic base, the doped epitaxy region(s), and the resistor(s) are stacked upon one another in a channel between the emitter layer and the collector. Various circuit configurations and structures are described including a common-collector circuit, a common-emitter circuit, and an emitter-degenerate circuit. Methods of making these configuration/structures are disclosed.

Structures for a bipolar junction transistor and methods of fabricating a structure for a bipolar junction transistor. The structure includes a first base layer, a second base layer, a first terminal positioned between the first base layer and the second base layer, a second terminal, and a third terminal. The first base layer, the second base layer, and the first terminal are positioned between the second terminal and the third terminal. For example, the first terminal may be positioned in a vertical direction between the first and second base layers.

A method includes forming a deep well region of a first conductivity type in a substrate, implanting a portion of the deep well region to form a first gate, and implanting the deep well region to form a well region. The well region and the first gate are of a second conductivity type opposite the first conductivity type. An implantation is performed to form a channel region of the first conductivity type over the first gate. A portion of the deep well region overlying the channel region is implanted to form a second gate of the second conductivity type. A source/drain implantation is performed to form a source region and a drain region of the first conductivity type on opposite sides of the second gate. The source and drain regions are connected to the channel region, and overlap the channel region and the first gate.

A semiconductor device is described including a substrate and a plurality of layers. The semiconductor device includes a cascode arrangement of a first bipolar transistor and a second bipolar transistor. A first-bipolar-transistor-collector of the first bipolar transistor and a second-bipolar-transistor-emitter of the second bipolar transistor are at least partially located in a common region in the same layer of the semiconductor device.

A method includes forming a deep well region of a first conductivity type in a substrate, implanting a portion of the deep well region to form a first gate, and implanting the deep well region to form a well region. The well region and the first gate are of a second conductivity type opposite the first conductivity type. An implantation is performed to form a channel region of the first conductivity type over the first gate. A portion of the deep well region overlying the channel region is implanted to form a second gate of the second conductivity type. A source/drain implantation is performed to form a source region and a drain region of the first conductivity type on opposite sides of the second gate. The source and drain regions are connected to the channel region, and overlap the channel region and the first gate.

Certain embodiments include a cubic boron nitride (c-BN) device. The c-BN device includes a n/n+ Schottky diode and a n/p/n+ bipolar structure. The n/n+ Schottky diode and the /p/n+ bipolar structure are on a single-crystal diamond platform.

A current source includes a substrate, a base region of a first doping type formed in the substrate, an emitter region of a second doping type formed in the substrate and surrounding the base region, a first collector region of the second doping type formed in the base region, and at least one second collector region of the second doping type formed in the base region, wherein the emitter region includes a deep-well portion and an extending portion, the deep-well portion situated beneath the base region, the extending portion laterally surrounding the base region, the extending portion joined at its bottom to the deep-well portion, the extending portion being flush at its top with a top surface of the substrate. A method of forming the current source is also disclosed.