The present disclosure relates to semiconductor structures and, more particularly, to bipolar transistors and methods of manufacture. The structure includes: a base region composed of a semiconductor on insulator material; an emitter region above the base region; and a collector region under the base region and within a cavity of a buried insulator layer.

A semiconductor device includes a plurality of unit transistors that are arranged on a surface of a substrate in a first direction. Input capacitive elements are arranged so as to correspond to the unit transistors. An emitter common wiring line is connected to emitter layers of the unit transistors. A via-hole extending from the emitter common wiring line to a back surface of the substrate is disposed at a position overlapping the emitter common wiring line. A collector common wiring line is connected to collector layers of the unit transistors. The input capacitive elements, the emitter common wiring line, the unit transistors, and the collector common wiring line are arranged in this order in a second direction. Base wiring lines that connect the input capacitive elements to base layers of the corresponding unit transistors intersect the emitter common wiring line without physical contact.

A semiconductor device includes a semiconductor substrate, a first semiconductor region of a first semiconductor type, formed within the semiconductor substrate, wherein the first semiconductor region includes a first doped region formed in a lower portion of the first semiconductor region and a second doped region formed over the first doped region in an upper portion of the first semiconductor region. A defect layer having an upper surface formed in an upper portion of the first doped region. A second semiconductor region of a second semiconductor type is formed over the first semiconductor region.

Structures for a bipolar junction transistor and methods of forming a structure for a bipolar junction transistor. The structure includes a dielectric layer having a cavity, a first semiconductor layer on the dielectric layer, a collector including a portion on the first semiconductor layer, an emitter including a portion on the first semiconductor layer, and a second semiconductor layer that includes a first section in the cavity and a second section. The second section of the second semiconductor layer is laterally positioned between the portion of the collector and the portion of the emitter.

A semiconductor device and a method of making a semiconductor device are described. The device includes an emitter. The device also includes a collector. The device further includes a base stack. The base is located between the emitter and the collector. The base stack includes an intrinsic base region. The device further includes a base electrode. The base electrode comprises a silicide. The silicide of the base electrode may be in direct contact with the base stack. The device may be a heterojunction bipolar transistor.

Structures for a bipolar junction transistor and methods of forming a structure for a bipolar junction transistor. The structure includes a first terminal having a first raised semiconductor layer having a top surface and a side surface, a second terminal having a second raised semiconductor layer, and a base layer positioned in a lateral direction between the first raised semiconductor layer of the first terminal and the second raised semiconductor layer of the second terminal. The structure further includes a contact positioned to overlap with the top surface and the side surface of the first raised semiconductor layer.

The present disclosure relates to semiconductor structures and, more particularly, to transistor with wrap-around extrinsic base and methods of manufacture. The structure includes: a substrate; a collector region within the substrate; an emitter region over the substrate and which comprises silicon based material; an intrinsic base; and an extrinsic base overlapping the emitter region and the intrinsic base; an extrinsic base overlapping the emitter region and the intrinsic base; and an inverted “T” shaped spacer which separates the emitter region from the extrinsic base and the collector region from the emitter region.

The present disclosure relates to semiconductor structures and, more particularly, to transistor with wrap-around extrinsic base and methods of manufacture. The structure includes: a substrate; a collector region within the substrate; an emitter region over the substrate and which comprises mono-crystal silicon based material; an intrinsic base under the emitter region and comprising semiconductor material; and an extrinsic base surrounding the emitter and over the intrinsic base.

Structures for a bipolar junction transistor and methods of fabricating a structure for a bipolar junction transistor. The structure includes a collector having a first semiconductor layer, an emitter having a second semiconductor layer, an intrinsic base including nanosheet channel layers positioned with a spaced arrangement in a layer stack, and a base contact laterally positioned between the first and second semiconductor layers. Each nanosheet channel layer extends laterally from the first semiconductor layer to the second semiconductor layer. Sections of the base contact are respectively positioned in spaces between the nanosheet channel layers. The structure further includes first spacers laterally positioned between the sections of the base contact and the first semiconductor layer, and second spacers laterally positioned between the sections of the base contact and the second semiconductor layer.

Structures for a bipolar junction transistor and methods of fabricating a structure for a bipolar junction transistor. The structure includes a first terminal having a first raised semiconductor layer, a second terminal having a second raised semiconductor layer, and a base layer positioned laterally between the first raised semiconductor layer and the second raised semiconductor layer. The structure further includes a spacer positioned laterally positioned between the first raised semiconductor layer and the base layer. The spacer includes a dielectric material and an airgap surrounded by the dielectric material.