Abstract: The present disclosure relates to semiconductor structures and, more particularly, to switches in a bulk substrate and methods of manufacture. The structure includes: at least one active device having a channel region of a first semiconductor material; a single air gap under the channel region of the at least one active device; and a second semiconductor material being coplanar with and laterally bounding at least one side of the single air gap, the second semiconductor material being different material than the first semiconductor material.

Abstract: A structure includes a semiconductor-on-insulator (SOI) substrate including a semiconductor substrate, a buried insulator layer over the semiconductor substrate, and an SOI layer over the buried insulator layer. At least one polycrystalline active region fill shape is in the SOI layer. A polycrystalline isolation region may be in the semiconductor substrate under the buried insulator layer. The at least one polycrystalline active region fill shape is laterally aligned over the polycrystalline isolation region, where provided. Where provided, the polycrystalline isolation region may extend to different depths in the semiconductor substrate.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to photodiodes and/or PIN diode structures and methods of manufacture. The structure includes: at least one vertical pillar feature within a trench; a photosensitive semiconductor material extending laterally from sidewalls of the at least one vertical pillar feature; and a contact electrically connecting to the photosensitive semiconductor material.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to gate structures and methods of manufacture. The structure includes: a gate structure comprising a horizontal portion and a substantially vertical stem portion; and an air gap surrounding the substantially vertical stem portion and having a curved surface under the horizontal portion.

Abstract: Disclosed is an integrated circuit (IC) structure that includes a through-metal through-substrate interconnect. The interconnect extends essentially vertically through a device level metallic feature on a frontside of a substrate, extends downward from the device level metallic feature into or completely through the substrate (e.g., to contact a backside metallic feature below), and extends upward from the device level metallic feature through interlayer dielectric (ILD) material (e.g., to contact a BEOL metallic feature above). The device level metallic feature can be, for example, a metallic source/drain region of a transistor, such as a high electron mobility transistor (HEMT) or a metal-insulator-semiconductor high electron mobility transistor (MISHEMT), which is formed on the frontside of the substrate. The backside metallic feature can be a grounded metal layer. The BEOL metallic feature can be a metal wire in one of the BEOL metal levels. Also disclosed is an associated method.

Abstract: A photodetector array includes a substrate, and an array of pixels over the substrate. Each pixel includes a set of diffraction gratings directly on a semiconductor photodetector. A pitch of the set of diffraction gratings associated with each pixel in the array of pixels are different to enable each pixel to detect a specific wavelength of light different than other pixels of the array of pixels. An air cavity may be provided in the substrate under the germanium photodetector to improve light absorption. A method of forming the photodetector array is also disclosed.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to field effect transistors and methods of manufacture. The structure includes: at least one gate structure having source/drain regions; at least one isolation structure within the source/drain regions in a substrate material; and semiconductor material on a surface of the at least one isolation structure in the source/drain regions.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to photodetectors used with a broadband signal and methods of manufacture. The structure includes: a first photodetector; a second photodetector adjacent to the first photodetector; a first airgap of a first size under the first photodetector structured to detect a first wavelength of light; and a second airgap of a second size under the second photodetector structured to detect a second wavelength of light.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to switches in a bulk substrate and methods of manufacture. The structure includes: at least one active device having a channel region of a first semiconductor material; a single air gap under the channel region of the at least one active device; and a second semiconductor material being coplanar with and laterally bounding at least one side of the single air gap, the second semiconductor material being different material than the first semiconductor material.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to photodetectors used with a broadband signal and methods of manufacture. The structure includes: a first photodetector; a second photodetector adjacent to the first photodetector; a first airgap of a first size under the first photodetector structured to detect a first wavelength of light; and a second airgap of a second size under the second photodetector structured to detect a second wavelength of light.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to a waveguide structure with attenuator and methods of manufacture. The structure includes: a waveguide structure including semiconductor material; an attenuator underneath the waveguide structure; an airgap structure vertically aligned with and underneath the waveguide structure and the attenuator; and shallow trench isolation structures on sides of the waveguide structure and merging with the airgap structure.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to airgap structures in a doped region under one or more transistors and methods of manufacture. The structure includes: a semiconductor material comprising a doped region; one or more sealed airgap structures breaking up the doped region of the semiconductor material; and a field effect transistor over the one or more sealed airgap structures and the semiconductor material.

Abstract: Disclosed are a transistor and a method for forming the transistor. The method includes concurrently forming gate and source/drain openings through an uppermost layer (i.e., a dielectric layer) in a stack of layers. The method can further include: depositing and patterning gate conductor material so that a first gate section is in the gate opening and a second gate section is above the gate opening and so that the source/drain openings are exposed; extending the depth of the source/drain openings; and depositing and patterning source/drain conductor material so that a first source/drain section is in each source/drain opening and a second source/drain section is above each source/drain opening. Alternatively, the method can include: forming a plug in the gate opening and sidewall spacers in the source/drain openings; extending the depth of source/drain openings; depositing and patterning the source/drain conductor material; and subsequently depositing and patterning the gate conductor material.

Abstract: A structure includes an active device over an area of a substrate, and a heat spreading isolation structure adjacent the active device. The isolation structure includes a dielectric layer above a heat-conducting layer. The heat-conducting layer may include polycrystalline graphite. The heat-conducting layer provides a heat sink, which provides a high thermal conductivity path for heat with low electrical conductivity. The heat-conducting layer may extend into the substrate. The substrate may include an SOI substrate in which case the heat-conducting layer may extend through the buried insulator thereof.

Abstract: Disclosed is a structure with ultralow-K (ULK) dielectric-gap wrapped contact(s). The structure includes an opening, which extends through a dielectric layer and is aligned above a device. A contact is within the opening and electrically connected to the device. Instead of the contact completely filling the opening, a ULK dielectric-gap (e.g., an air or gas-filled gap or a void) at least partially separates the contact from the sidewall(s) of the contact opening and further wraps laterally around the contact. Also disclosed is a method for forming the structure and, particularly, for forming a ULK dielectric-gap by etching back an exposed top end of an adhesive layer initially lining a contact opening to form a gap between the sidewall(s) of the opening and the contact and then capping the gap with an additional dielectric layer such that the gap is filled with air or gas or is under vacuum.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to a waveguide structure with attenuator and methods of manufacture. The structure includes: a waveguide structure including semiconductor material; an attenuator underneath the waveguide structure; an airgap structure vertically aligned with and underneath the waveguide structure and the attenuator; and shallow trench isolation structures on sides of the waveguide structure and merging with the airgap structure.

Abstract: A photodetector array includes a substrate, and an array of pixels over the substrate. Each pixel includes a set of diffraction gratings directly on a semiconductor photodetector. A pitch of the set of diffraction gratings associated with each pixel in the array of pixels are different to enable each pixel to detect a specific wavelength of light different than other pixels of the array of pixels. An air cavity may be provided in the substrate under the germanium photodetector to improve light absorption. A method of forming the photodetector array is also disclosed.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to an avalanche photodiode and methods of manufacture. The structure includes: a substrate material having a trench with sidewalls and a bottom composed of the substrate material; a first semiconductor material lining the sidewalls and the bottom of the trench; a photosensitive semiconductor material provided on the first semiconductor material; and a third semiconductor material provided on the photosensitive semiconductor material.

Abstract: The present disclosure relates to semiconductor structures and, more particularly, to photodiodes and/or PIN diode structures and methods of manufacture. The structure includes: at least one fin including substrate material, the at least one fin including sidewalls and a top surface; a trench on opposing sides of the at least one fin; a first semiconductor material lining the sidewalls and the top surface of the at least one fin, and a bottom surface of the trench; a photosensitive semiconductor material on the first semiconductor material and at least partially filling the trench; and a third semiconductor material on the photosensitive semiconductor material.

Abstract: Disclosed is a bulk semiconductor structure that includes a semiconductor substrate with a multi-level polycrystalline semiconductor region that includes one or more first-level portions (i.e., buried portions) and one or more second-level portions (i.e., non-buried portions). Each first-level portion can be within the semiconductor substrate some distance below the top surface (i.e., buried), can be aligned below a monocrystalline semiconductor region and/or a trench isolation region, and can have a first maximum depth. Each second-level portion can be within the semiconductor substrate at the top surface, can be positioned laterally adjacent to a trench isolation region, and can have a second maximum depth that is less than the first maximum depth. Also disclosed herein are method embodiments for forming the bulk semiconductor structure wherein the first-level and second-level portions of the multi-level polycrystalline semiconductor region are concurrently formed (e.g., using a single module).