The subject disclosure relates to high mobility complementary metal-oxide-semiconductor (CMOS) devices and techniques for forming the CMOS devices with fins formed directly on the insulator. According to an embodiment, a method for forming such a high mobility CMOS device can comprise forming, via a first epitaxial growth of a first material, first pillars within first trenches formed within a dielectric layer, wherein the dielectric layer is formed on a silicon substrate, and wherein the first pillars comprise first portions with defects and second portions without the defects. The method can further comprise forming second trenches within a first region of the dielectric layer, and further forming second pillars within the second trenches via a second epitaxial growth of one or more second materials using the second portions of the first pillars as seeds for the second epitaxial growth.

Various embodiments of the present disclosure are directed towards a method for forming a bipolar junction transistor (BJT). A dielectric film is deposited over a substrate and comprises a lower dielectric layer, an upper dielectric layer, and an intermediate dielectric layer between the lower and upper dielectric layers. A first semiconductor layer is deposited over the dielectric film and is subsequently patterned to form an opening exposing the dielectric film. A first etch is performed into the upper dielectric layer through the opening to extend the opening to the intermediate dielectric layer. Further, the first etch stops on the intermediate dielectric layer and laterally undercuts the first semiconductor layer. Additional etches are performed to extend the opening to the substrate. A lower base structure and an emitter are formed stacked in and filling the opening, and the first semiconductor layer is patterned to form an upper base structure.

The present disclosure relates to semiconductor structures and, more particularly, to a heterojunction bipolar transistor having an emitter base junction with a silicon-oxygen lattice interface and methods of manufacture. The device includes: a collector region buried in a substrate; shallow trench isolation regions, which isolate the collector region buried in the substrate; a base region on the substrate and over the collector region; an emitter region composed of a single crystalline of semiconductor material and located over with the base region; and an oxide interface at a junction of the emitter region and the base region.

The present disclosure relates to semiconductor structures and, more particularly, to a device with a marker layer and methods of manufacture. The device includes: a collector region; an intrinsic base region above the collector region; an emitter region comprising emitter material and a marker layer vertically between the intrinsic base region and the emitter material; and an extrinsic base region in electrical contact with the intrinsic base region.

Transistor-based sensors and fabrication methods for a transistor-based sensor. A semiconductor layer is arranged over a substrate, and an interconnect structure is arranged over the semiconductor layer and the substrate. The semiconductor layer includes first sections composed of a semiconductor material, second sections composed of the semiconductor material, and cavities. The first sections have an alternating arrangement with the second sections in a lateral direction. The semiconductor material of the first sections is polycrystalline, and the semiconductor material of the second sections is single-crystal. First and second openings each extend in a vertical direction through the metallization levels of the interconnect structure to the semiconductor layer or through the substrate to the semiconductor layer. The first opening defines a first fluid inlet coupled to the cavities, and the second opening defines a first fluid outlet coupled to the cavities.

The present disclosure relates to semiconductor structures and, more particularly, to virtual bulk in semiconductor on insulator technology and methods of manufacture. The structure includes a heterojunction bipolar transistor formed on a semiconductor on insulator (SOI) wafer with a doped sub-collector material in a buried insulator region under a semiconductor substrate of the SOI wafer.

Structures for a heterojunction bipolar transistor and methods of forming a structure for a heterojunction bipolar transistor. A collector layer includes an inclined side surface, and a dielectric layer is positioned in a lateral direction adjacent to the inclined side surface of the collector layer. An intrinsic base is disposed over the collector layer, and an emitter is disposed over the intrinsic base. An airgap is positioned between the dielectric layer and the inclined side surface of the collector layer in the lateral direction, and an extrinsic base is positioned in the lateral direction adjacent to the intrinsic base. The extrinsic base is positioned over the airgap.

Structures for a heterojunction bipolar transistor and methods of forming a structure for a heterojunction bipolar transistor. A first heterojunction bipolar transistor includes a first emitter, a first collector, and a first base layer having a portion positioned between the first emitter and the first collector. A second heterojunction bipolar transistor includes a second emitter, a second collector, and a second base layer having a portion positioned between the second emitter and the second collector. The first and second base layers each comprise silicon-germanium, the first base layer includes a first germanium profile, and the second base layer includes a second germanium profile that is identical to the first germanium profile.

Structures for a heterojunction bipolar transistor and methods of forming a structure for a heterojunction bipolar transistor. A collector layer includes an inclined side surface, and a dielectric layer is positioned in a lateral direction adjacent to the inclined side surface of the collector layer. An intrinsic base is disposed over the collector layer, and an emitter is disposed over the intrinsic base. An airgap is positioned between the dielectric layer and the inclined side surface of the collector layer in the lateral direction, and an extrinsic base is positioned in the lateral direction adjacent to the intrinsic base. The extrinsic base is positioned over the airgap.

One illustrative device disclosed herein includes a semiconductor substrate, a bipolar junction transistor (BJT) device that comprises a collector, a base and an emitter, at least one piezoelectric structure comprising a piezoelectric material positioned adjacent the BJT device, and at least first and second conductive contact structures that are conductively coupled to the piezoelectric structure.