Disclosed examples provide fabrications methods and integrated circuits with back ballasted NPN bipolar transistors which include an n-type emitter in a P doped region, a p-type base with a first side facing the emitter, and an n-type collector laterally spaced from a second side of the base, where the collector includes a first side facing the second side of the base, an opposite second side, a silicided first collector portion and a silicide blocked second collector portion covered with a non-conductive dielectric that extends laterally between the first collector portion and the second side of the collector to provide back side ballasting for lateral breakdown and low current conduction via a deep N doped region while the vertical NPN turns on at a high voltage.

A method includes providing a semiconductor structure having an active region and an isolation structure adjacent to the active region, the active region having source and drain regions sandwiching a channel region for a transistor, the semiconductor structure further having a gate structure over the channel region. The method further includes etching a trench in one of the source and drain regions, wherein the trench exposes a portion of a sidewall of the isolation structure, epitaxially growing a first semiconductor layer in the trench, epitaxially growing a second semiconductor layer over the first semiconductor layer, changing a crystalline facet orientation of a portion of a top surface of the second semiconductor layer by an etching process, and epitaxially growing a third semiconductor layer over the second semiconductor layer after the changing of the crystalline facet orientation.

The current disclosure describes techniques for forming gate-all-around (GAA) devices from stacks of separately formed nanowire semiconductor strips. The separately formed nanowire semiconductor strips are tailored for the respective GAA devices. A trench is formed in a first stack of epitaxy layers to define a space for forming a second stack of epitaxy layers. The trench bottom is modified to have determined or known parameters in the shapes or crystalline facet orientations. The known parameters of the trench bottom are used to select suitable processes to fill the trench bottom with a relatively flat base surface.

A bipolar transistor is described. In accordance with one aspect of the present invention the bipolar transistor comprises a semiconductor body including a collector region and a base region arranged on top of the collector region. The base region has a first crystalline structure and is at least partly doped with dopants of a first doping type. The collector region is laterally enclosed by a trench isolation and is doped with dopants of a second doping type. The transistor further comprises a conductive base contact layer laterally enclosing the base region which is doped with dopants of the first doping type. The base contact layer comprises a part with the first crystalline structure and a part with a second crystalline structure, wherein the part with the second crystalline structure laterally encloses the part with the first crystalline structure. The transistor further comprises an emitter region arranged on the base region, wherein the emitter region is doped with dopants of the second doping type and forming a pn-junction with the base region.

A method includes providing a semiconductor structure having an active region and an isolation structure adjacent to the active region, the active region having source and drain regions sandwiching a channel region for a transistor, the semiconductor structure further having a gate structure over the channel region. The method further includes etching a trench in one of the source and drain regions, wherein the trench exposes a portion of a sidewall of the isolation structure, epitaxially growing a first semiconductor layer in the trench, epitaxially growing a second semiconductor layer over the first semiconductor layer, changing a crystalline facet orientation of a portion of a top surface of the second semiconductor layer by an etching process, and epitaxially growing a third semiconductor layer over the second semiconductor layer after the changing of the crystalline facet orientation.

The present disclosure relates to semiconductor structures and, more particularly, to a bipolar transistor and methods of manufacture. The structure includes: a collector region in a semiconductor substrate; a base region adjacent to the collector region; and an emitter extending above the base region and comprising semiconductor material and a hardmask surrounding a lower portion of the semiconductor material.

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.

A bipolar junction transistor includes an extrinsic collector region buried in a semiconductor substrate under an intrinsic collector region. Carbon-containing passivating regions are provided to delimit the intrinsic collector region. An insulating layer on the intrinsic collector region includes an opening within which an extrinsic base region is provided. A semiconductor layer overlies the insulating layer, is in contact with the extrinsic base region, and includes an opening with insulated sidewalls. The collector region of the transistor is provided between the insulated sidewalls.

A transistor module includes a substrate; a transistor on the substrate; a dielectric layer disposed over the transistor and the substrate; a metal layer disposed over the dielectric layer and the transistor, the metal layer contacting a portion of the transistor; a metal pillar disposed over the metal layer; and a dielectric cushion disposed between the metal layer and the metal pillar over the transistor. The dielectric cushion includes dielectric material that is softer than the metal pillar, for reducing strain on semiconductor junctions when at least one of tensile or compressive stress is exerted on the metal pillar with respect to the substrate. The transistor module may further include at least one buttress formed between the metal layer and the substrate, adjacent to the transistor, for further reducing strain on the semiconductor junctions by providing at least one corresponding alternative stress path that substantially bypasses the transistor.

Disclosed examples provide fabrications methods and integrated circuits with back ballasted NPN bipolar transistors which include an n-type emitter in a P doped region, a p-type base with a first side facing the emitter, and an n-type collector laterally spaced from a second side of the base, where the collector includes a first side facing the second side of the base, an opposite second side, a silicided first collector portion and a silicide blocked second collector portion covered with a non-conductive dielectric that extends laterally between the first collector portion and the second side of the collector to provide back side ballasting for lateral breakdown and low current conduction via a deep N doped region while the vertical NPN turns on at a high voltage.