The present disclosure relates to semiconductor structures and, more particularly, to a lateral bipolar transistor and methods of manufacture. The structure includes: an extrinsic base having at least one sidewall with a gradient concentration of semiconductor material; an emitter on a first side of the extrinsic base; and a collector on a second side of the extrinsic base.

The present disclosure relates to semiconductor structures and, more particularly, to a lateral bipolar transistor and methods of manufacture. The structure includes a lateral bipolar junction transistor including an extrinsic base region and a bilayer dielectric spacer on sidewalls of the extrinsic base region, and a p-n junction positioned under the bilayer dielectric spacer between the extrinsic base region and at least an emitter region.

Structures for a bipolar junction transistor and methods of forming a structure for a bipolar junction transistor. The structure includes a substrate having a well, a first terminal including a first raised semiconductor layer, a second terminal including 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 base layer has an overlapping arrangement with the well. The structure further includes a dielectric layer positioned in a vertical direction between the first terminal and the substrate, the second terminal and the substrate, and the base layer and the substrate.

A disclosed structure includes a bipolar junction transistor (BJT) and a method of forming the structure. The structure includes a semiconductor layer on an insulator layer. The BJT includes a base region positioned laterally between emitter and collector regions. The emitter region includes an emitter portion of the semiconductor layer and an emitter semiconductor layer, which is within an emitter cavity in the insulator layer, which extends through an emitter opening in the emitter portion, and which covers the top of the emitter portion. The collector region includes a collector portion of the semiconductor layer and a collector semiconductor layer, which is within a collector cavity in the insulator layer, which extends through a collector opening in the collector portion, and which covers the top of the collector portion. Optionally, the structure also includes air pockets within the emitter and collector cavities.

The present disclosure relates to semiconductor structures and, more particularly, to a bipolar transistor with a collector contact and methods of manufacture. The structure includes: a lateral bipolar transistor which includes an emitter, a base and a collector; an emitter contact to the emitter; a base contact to the base; and a collector contact to the collector and extending to an underlying substrate underneath the collector.

Structures for a bipolar junction transistor and methods of forming a structure for a bipolar junction transistor. The structure comprises a first terminal including a first raised semiconductor layer, a second terminal including 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 comprises a modulator including a semiconductor layer in direct contact with the base layer. The base layer has a first conductivity type, and the semiconductor layer has a second conductivity type opposite to the first conductivity type.

An article of manufacture, having a semiconductor layer and a dielectric layer. The semiconductor layer comprising a first surface and a second surface. The dielectric layer located adjacent to the first surface of the semiconductor layer. One or more base portions of the semiconductor in direct contact with and extending from the dielectric layer. One or more collector portions of the semiconductor in direct contact with and extending from the dielectric layer. One or more emitter portions of the semiconductor in direct contact with and extending from the dielectric layer. The one or more collector portions are spaced apart from the one or more emitter portions by the one or more base portions.

After forming an epitaxial germanium layer over a germanium-on-insulator substrate including an insulator layer and a doped germanium layer overlying the insulator layer, the doped germanium layer is selectively removed and a passivation layer is formed within a space between the epitaxial germanium layer and the insulator layer that is formed by removal of the doped germanium layer. A lateral bipolar transistor is subsequently formed in the epitaxial germanium layer.

The disclosure provides a bipolar transistor structure with multiple bases, and related methods. A bipolar transistor structure includes a first emitter/collector (E/C) material above an insulator. The first E/C material has first sidewall and a second sidewall over the insulator. A first base is above the insulator adjacent the first sidewall of the first E/C material. A second base is above the insulator adjacent the second sidewall of the first E/C material. A second E/C material is above the insulator and adjacent the first base. A width of the first base between the first E/C material and the second E/C material is less than a width of the first E/C material, and the first base protrudes horizontally outward from an end of the first E/C material and an end of the second E/C material.

Aspects of the disclosure provide an integrated circuit (IC) structure with a bipolar transistor stack within a substrate. The bipolar transistor stack may include: a collector, a base on the collector, and an emitter on a first portion of the base. A horizontal width of the emitter is less than a horizontal width of the base, and an upper surface of the emitter is substantially coplanar with an upper surface of the substrate. An extrinsic base structure is on a second portion of the base of the bipolar transistor stack, and horizontally adjacent the emitter. The extrinsic base structure includes an upper surface above the upper surface of the substrate.