Abstract: Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed to be in contact with at least one piezoelectric substrate. The method further includes forming a micro-electro-mechanical structure (MEMS) comprising a MEMS beam in which, upon actuation, the MEMS beam will turn on the at least one piezoelectric filter structure by interleaving electrodes in contact with the piezoelectric substrate or sandwiching the at least one piezoelectric substrate between the electrodes.

Abstract: Device structures for a field-effect transistor with a body contact and methods of forming such device structures. An opening is formed that extends through a device layer of a silicon-on-insulator (SOI) substrate and into a buried oxide layer of the silicon-on-insulator substrate. The buried oxide layer is laterally etched at the location of the opening to define a cavity in the buried oxide layer. The cavity is located partially beneath a section of the device layer, and the cavity is filled with a semiconductor material to form a body contact. A well is formed in the section of the device layer, and the body contact is coupled with a portion of the well.

Abstract: Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed on a piezoelectric substrate. The method further includes forming a micro-electro-mechanical structure (MEMS) comprising a MEMS beam formed above the piezoelectric substrate and at a location in which, upon actuation, the MEMS beam shorts the piezoelectric filter structure by contacting at least one of the plurality of electrodes.

Abstract: A method for fabricating a backside device contact using a silicon-on-insulator substrate that includes a device layer, a buried insulator layer, and a handle wafer, includes forming a trench in the device layer. The trench is filled with a contact plug. The backside device contact includes the contact plug. After the trench is filled with the contact plug, the handle wafer is removed to reveal the buried insulator layer. The buried insulator layer is partially removed to expose the trench containing the contact plug. A final substrate is connected to the buried insulator layer such that the contact plug contacts metallization of the final substrate. A device structure is formed using the device layer.

Abstract: A back-side device structure with a silicon-on-insulator substrate that includes: a first dielectric layer that includes a first via that communicates with a trench, a contact plug that fills the trench, and a first contact formed in a second dielectric layer. The first contact fills the first via and connects with the contact plug and a wire formed in a third dielectric layer. A final substrate is connected to a buried insulator layer of the silicon-on-insulator substrate such that the contact plug contacts metallization of the final substrate.

Abstract: A method for fabricating a backside device contact using a silicon-on-insulator substrate that includes a device layer, a buried insulator layer, and a handle wafer, includes forming a trench in the device layer. A trench is formed in the device layer. A sacrificial plug is formed in the trench. The handle wafer is removed to reveal the buried insulator layer. The buried insulator layer is partially removed to expose the sacrificial plug at a bottom of the trench. The sacrificial plug is removed. Backside processing of the buried insulator layer is performed. The trench is filled with a conductor to form a contact plug. A final substrate is connected to the buried insulator layer such that the contact plug contacts metallization of the final substrate.

Abstract: Photodiode structures and methods of manufacture are disclosed. The method includes forming a waveguide structure in a dielectric layer. The method further includes forming a Ge material in proximity to the waveguide structure in a back end of the line (BEOL) metal layer. The method further includes crystallizing the Ge material into a crystalline Ge structure by a low temperature annealing process with a metal layer in contact with the Ge material.

Abstract: A field effect transistor (FET) with an underlying airgap and methods of manufacture are disclosed. The method includes forming an amorphous layer at a predetermined depth of a substrate. The method further includes forming an airgap in the substrate under the amorphous layer. The method further includes forming a completely isolated transistor in an active region of the substrate, above the amorphous layer and the airgap.

Abstract: A method for fabricating a backside contact using a silicon-on-insulator substrate that includes a device layer, a buried insulator layer, and a handle wafer. The method includes forming a first switch and a second switch in the device layer. An electrically-conducting connection is formed in a trench. The handle wafer is removed. After the handle wafer is removed, the buried insulator layer is partially removed to expose the electrically-conducting connection. After the buried insulator layer is partially removed, a final substrate is connected to the buried insulator layer such that the electrically-conducting connection contacts the final substrate.

Abstract: A field effect transistor (FET) with an underlying airgap and methods of manufacture are disclosed. The method includes forming an amorphous layer at a predetermined depth of a substrate. The method further includes forming an airgap in the substrate under the amorphous layer. The method further includes forming a completely isolated transistor in an active region of the substrate, above the amorphous layer and the airgap.

Abstract: A device structure with a backside contact includes a silicon-on-insulator substrate including a device layer, a buried insulator layer, and an electrically-conducting connection in a trench. A final substrate is connected to the buried insulator layer such that the electrically-conducting connection contacts the final substrate.

Abstract: A method for fabricating a backside contact using a silicon-on-insulator substrate that includes a device layer, a buried insulator layer, and a handle wafer. The method includes forming an electrically-conducting connection in a trench. The handle wafer is removed. After the handle wafer is removed, the buried insulator layer is partially removed to expose the electrically-conducting connection. After the buried insulator layer is partially removed, a final substrate is connected to the buried insulator layer such that the electrically-conducting connection contacts the final substrate.

Abstract: A back-side device structure with a silicon-on-insulator substrate that includes a device layer, a buried insulator layer, a trench that extends through the device layer and that partially extends through the buried insulator layer, at least one dielectric layer that is formed on the device layer and includes a first opening that communicates with the trench and a contact plug that fills the trench. A final substrate is connected to the buried insulator layer such that the contact plug contacts metallization of the final substrate. The contact plug is externally connected with a source to provide signals to the back-side device structure through a wire formed in the at least one dielectric layer.

Abstract: Assemblies including a device layer of a silicon-on-insulator (SOI) substrate and a replacement substrate replacing a handle wafer of the SOI substrate, and methods for transferring the device layer of the SOI substrate from the handle wafer to the replacement substrate. A device structure is formed in a first section of the handle wafer, and a second section of the handle wafer adjoining the first section of the handle wafer is removed to expose a surface of the buried dielectric layer of the silicon-on-insulator substrate. A permanent substrate is attached to the surface of the buried dielectric layer. When the permanent substrate is attached to the surface of the buried dielectric layer, the section of the handle wafer is received inside a cavity defined in the permanent substrate.

Abstract: Device structures and fabrication methods for a backside contact to a final substrate. An electrically-conducting connection is formed that extends through a device layer of a silicon-on-insulator substrate and partially through a buried insulator layer of the silicon-on-insulator substrate. After the electrically-conducting connection is formed, a handle wafer of the silicon-on-insulator substrate is removed. After the handle wafer is removed, the buried insulator layer is partially removed to expose the electrically-conducting connection. After the buried insulator layer is partially removed, a final substrate is coupled to the buried insulator layer such that the electrically-conducting connection is coupled with the final substrate.

Abstract: Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed to be in contact with at least one piezoelectric substrate. The method further includes forming a micro-electro-mechanical structure (MEMS) comprising a MEMS beam in which, upon actuation, the MEMS beam will turn on the at least one piezoelectric filter structure by interleaving electrodes in contact with the piezoelectric substrate or sandwiching the at least one piezoelectric substrate between the electrodes.

Abstract: A design structure for an integrated radio frequency (RF) filter on a backside of a semiconductor substrate includes: a device on a first side of a substrate; a radio frequency (RF) filter on a backside of the substrate; and at least one substrate conductor extending from the front side of the substrate to the backside of the substrate and electrically coupling the RF filter to the device.

Abstract: Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed to be in contact with at least one piezoelectric substrate. The method further includes forming a micro-electro-mechanical structure (MEMS) comprising a MEMS beam in which, upon actuation, the MEMS beam will turn on the at least one piezoelectric filter structure by interleaving electrodes in contact with the piezoelectric substrate or sandwiching the at least one piezoelectric substrate between the electrodes.

Abstract: Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed on a piezoelectric substrate. The method further includes forming a fixed electrode with a plurality of fingers on the piezoelectric substrate. The method further includes forming a moveable electrode with a plurality of fingers over the piezoelectric substrate. The method further includes forming actuators aligned with one or more of the plurality of fingers of the moveable electrode.

Abstract: A semiconductor device may include a transistor gate in a device layer; an interconnect layer over the device layer; and an air gap extending through the interconnect layer to contact an upper surface of the transistor gate. The air gap provides a mechanism to reduce both on-resistance and off-capacitance for applications using SOI substrates such as radio frequency switches.