An integrated circuit includes an NMOS transistor, a PMOS transistor and a vertical bipolar transistor. The vertical bipolar transistor has an intrinsic base with a band barrier at least 25 meV high at a surface boundary of the intrinsic base, except at an emitter-base junction with an emitter, and except at a base-collector junction with a collector. The intrinsic base may be laterally surrounded by an extrinsic base with a higher dopant density than the intrinsic base, wherein a higher dopant density provides the band barrier at lateral surfaces of the intrinsic base. A gate may be disposed on a gate dielectric layer over a top surface boundary of the intrinsic base adjacent to the emitter. The gate is configured to accumulate the intrinsic base immediately under the gate dielectric layer, providing the band barrier at the top surface boundary of the intrinsic base.

Device structures, fabrication methods, and design structures for a bipolar junction transistor. A trench isolation region is formed in a substrate. The trench isolation region is coextensive with a collector in the substrate. A base layer is formed on the collector and on a first portion of the trench isolation region. A dielectric layer is formed on the base layer and on a second portion of the trench isolation region peripheral to the base layer. After the dielectric layer is formed, the trench isolation region is at least partially removed to define an air gap beneath the dielectric layer and the base layer.

An electrostatic discharge (ESD) protection device is disclosed including at least an NPN transistor and a PNP transistor coupled between a first node and a second node, wherein the ESD protection device may be configured to sink current from the first node to the second node in response to an ESD event. The transistors may be coupled such that a collector of the NPN may be coupled to the first node. A collector of the PNP may be coupled to the second node. A base of the NPN may be coupled to the emitter of the PNP. An emitter of the NPN may be coupled to a base of the PNP.

Methods of maintaining a state of a memory cell without interrupting access to the memory cell are provided, including applying a back bias to the cell to offset charge leakage out of a floating body of the cell, wherein a charge level of the floating body indicates a state of the memory cell; and accessing the cell.

Provided is a semiconductor element having, while maintaining the same integratability as a conventional MOSFET, excellent switch characteristics compared with the MOSFET, that is, having the S-value less than 60 mV/order at room temperature. Combining the MOSFET and a tunnel bipolar transistor having a tunnel junction configures a semiconductor element that shows an abrupt change in the drain current with respect to a change in the gate voltage (an S-value of less than 60 mV/order) even at a low voltage.

A heterojunction bipolar transistor (HBT) amplifier device includes transistor fingers arranged in parallel on a substrate. Each transistor finger includes a base/collector mesa stripe shaving a trapezoidal shaped cross-section with sloping sides, and having a base stacked on a collector; a set of emitter mesa stripes arranged on the base/collector mesa stripe; and emitter metallization formed over the set of emitter mesa stripes and the base/collector mesa. The emitter metallization includes a center portion for providing electrical and thermal connectivity to the emitter mesa stripes and extended portions extending beyond the base and overlapping onto the sloping sides of the base/collector mesa stripe for increasing thermal coupling to the collector. A common conductive pillar is formed over the transistor fingers for providing electrical and thermal conductivity. Also, thermal shunts are disposed on the substrate between adjacent transistor fingers, where the thermal shunts are electrically isolated from the transistor fingers.

Aspects of the present disclosure provides a device comprising a P-type semiconductor substrate, an N-type tub above the semiconductor substrate, a P-type region provided in the N-type tub isolated by one or more P-type isolation structures, and an N-type punch-through stopper provided under the P-type regions isolated by the isolation structure(s). The punch-through stopper is heavily doped compared to the N-type tub. The P-type region has a width between the two isolation structures that is equal to or less than that of the N-type punch-through stopper.

Methods, systems, circuits, and devices for power-packet-switching power converters using bidirectional bipolar transistors (BTRANs) for switching. Four-terminal three-layer BTRANs provide substantially identical operation in either direction with forward voltages of less than a diode drop. BTRANs are fully symmetric merged double-base bidirectional bipolar opposite-faced devices which operate under conditions of high non-equilibrium carrier concentration, and which can have surprising synergies when used as bidirectional switches for power-packet-switching power converters. BTRANs are driven into a state of high carrier concentration, making the on-state voltage drop very low.

A semiconductor memory cell includes a floating body region configured to be charged to a level indicative of a state of the memory cell selected from at least first and second states. A first region of the memory cell is in electrical contact with the floating body region. A second region of the memory cell is spaced apart from the first region and is also in electrical contact with the floating body region. A gate is positioned between the first and second regions. A back-bias region is configured to generate impact ionization when the memory cell is in one of the first and second states, and the back-bias region is configured so as not to generate impact ionization when the memory cell is in the other of the first and second states.

A method of making a graphene base transistor with reduced collector area comprising forming an electron injection region, forming an electron collection region, and forming a base region wherein the base region comprises one or more sheets of graphene and wherein the base region is intermediate the electron injection region and the electron collection region and forms electrical interfaces therewith.