Abstract: Disclosed herein are switching or other active FET configurations that implement a branch design with one or more interior FETs of a main path coupled in parallel with one or more auxiliary FETs of an auxiliary path. Such designs include a circuit assembly for performing a switching function that includes a branch with a plurality of main FETs coupled in series and an auxiliary FET coupled in parallel with an interior FET of the plurality of main FETs. The body nodes of the FETs can be interconnected and/or connected to a body bias network. The body nodes of the FETs can be connected to body bias networks to enable individual body bias voltages to be used for individual or groups of FETs.

Abstract: Disclosed herein are switching or other active FET configurations that implement a branch design with one or more interior FETs of a main path coupled in parallel with one or more auxiliary FETs of an auxiliary path. Such designs include a circuit assembly for performing a switching function that includes a branch with a plurality of main FETs coupled in series and an auxiliary FET coupled in parallel with an interior FET of the plurality of main FETs. The body nodes of the FETs can be interconnected and/or connected to a body bias network. The body nodes of the FETs can be connected to body bias networks to enable individual body bias voltages to be used for individual or groups of FETs.

Abstract: Disclosed herein are switching or other active field-effect transistor (FET) configurations that implement independently controlled main-auxiliary branch designs. Such designs include a circuit assembly for performing a switching function that includes a branch with a plurality of main FET devices in parallel with a plurality of auxiliary FET devices. The circuit assembly can include a plurality of gate bias networks where each controls one or more of the main FET devices. The circuit assembly includes a second plurality of gate bias networks that each controls one or more of the auxiliary FET devices.

Abstract: Disclosed herein are switching or other active FET configurations that implement a segmented main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a plurality of main-auxiliary pairs coupled in series, wherein each main-auxiliary pair includes a main field-effect transistor (FET) in parallel with an auxiliary FET. The circuit assembly also includes a gate bias network connected to the main FETs and configured to bias the main FETs in a strong inversion region. The circuit assembly also includes an auxiliary bias network connected to the auxiliary FETs and configured to bias the auxiliary FETs in a weak inversion region.

Abstract: Disclosed herein are switching or other active FET configurations that implement a main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a main path in parallel with a first auxiliary path and the main path in series with a second auxiliary path. The circuit assembly also includes a first gate bias network connected to the main path. The circuit assembly also includes a second gate bias network connected to the first auxiliary path. The circuit assembly also includes a third gate bias network connected to the second auxiliary path, the second gate bias network and the third gate bias network configured to improve linearity of the switching function.

Abstract: Field-effect transistor (FET) devices are described herein that include an insulator layer, a plurality of active field-effect transistors (FETs) formed from an active silicon layer implemented over the insulator layer, a substrate layer implemented under the insulator layer, and proximity electrodes for a plurality of the FETs that are each configured to receive a voltage and to generate an electric field between the proximity electrode and a region generally underneath a corresponding active FET. FET devices can be stacked wherein one or more of the FET devices in the stack includes a proximity electrode. The proximity electrodes can be biased together, biased in groups, and/or biased individually.

Abstract: The fabrication of field-effect transistor (FET) devices is described herein where the FET devices include one or more body contacts implemented between source, gate, drain (S/G/D) assemblies to improve the influence of a voltage applied at the body contact on the S/G/D assemblies. The FET devices can include source fingers and drain fingers interleaved with gate fingers. The source and drain fingers of a first S/G/D assembly can be electrically connected to the source and drain fingers of a second S/G/D assembly.

Abstract: A linearization circuit reduces intermodulation distortion in an amplifier that includes a first stage and a second stage. The linearization circuit receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency, generates an envelope signal based at least in part on a power level of the first signal, and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal, the first stage receives the adjusted signal, and the second stage does not receive the adjusted signal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation between the first frequency and the second frequency from the output of the amplifier.

Abstract: Disclosed herein are switching or other active FET configurations that implement a main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a main path in parallel with an auxiliary path. The circuit assembly also includes a gate bias network connected to the main path and to the auxiliary path, the main path and the auxiliary path each having different structures that are configured to improve linearity of the switching function.

Abstract: A linearization circuit that reduces intermodulation distortion in an amplifier output receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency. The linearization circuit generates an envelope signal based at least in part on a power level of the first signal and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal and the adjusted signal at a second terminal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation products that result from the intermodulation of the first frequency and the second frequency.

Abstract: Disclosed herein are switching or other active FET configurations that implement a segmented main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a plurality of main-auxiliary pairs coupled in series, wherein each main-auxiliary pair includes a main field-effect transistor (FET) in parallel with an auxiliary FET. The circuit assembly also includes a gate bias network connected to the main FETs and configured to bias the main FETs in a strong inversion region. The circuit assembly also includes an auxiliary bias network connected to the auxiliary FETs and configured to bias the auxiliary FETs in a weak inversion region.

Abstract: Disclosed herein are switching or other active FET configurations that implement a main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a main path in series with an auxiliary path. The circuit assembly also includes a first gate bias network connected to the main path. The circuit assembly also includes a second gate bias network connected to the auxiliary path, the second gate bias network configured to improve linearity of the switching function.

Abstract: Disclosed herein are systems and methods for reducing intermodulation distortion (IMD) in switches using distorter circuits and voltage buffers. A switch circuit can include a switch arm with a stack of field-effect transistors (FETs), a distorter arm that is configured to act as a compensation circuit to compensate for non-linearities in the switch arm, and a voltage buffer that is configured to protect the distorter arm from large voltage swings when transitioning between ON and OFF states. The gate width of the distorter arm can be orders of magnitude smaller than the gate widths of the switch FETs. The gate width of the voltage buffer FETs can be larger than the distorter arm and smaller than the switch arm. The distorter arm is configured to compensate for the non-linearity effect generated by the switch arm.

Abstract: In semiconductor switches, the isolation can be limited by the capacitive coupling between the switch input and the switch output. Ultra-high isolation can be achieved by adding a coupled transmission line to the semiconductor switch. The coupled transmission line introduces inductive coupling, which cancels at least a part of the capacitive coupling between the switch input and the switch output.

Abstract: Disclosed herein are switching or other active FET configurations that implement a main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a main path in parallel with an auxiliary path. The circuit assembly also includes a first gate bias network connected to the main path. The circuit assembly also includes a second gate bias network connected to the auxiliary path, the second gate bias network configured to improve linearity of the switching function.

Abstract: Disclosed herein are switching or other active FET configurations that implement a main-auxiliary branch design. Such designs include a circuit assembly for performing a switching function that includes a branch including a main path in parallel with an auxiliary path, both the main path and the auxiliary path having a plurality of field-effect transistors. The circuit assembly also includes a first gate bias network connected to the main path. The circuit assembly also includes a second gate bias network connected to a first subset of the plurality of FETs of the auxiliary path. The circuit assembly also includes a third gate bias network connected to a second subset of the plurality of FETs of the auxiliary path so that the third gate bias network switches on the auxiliary path when the main path is on for nonlinear cancellation, and switches off the auxiliary path when the main path is off to enable the branch to withstand maximum voltage swings.

Abstract: A method for fabricating a transistor device involves providing a substrate, forming an oxide layer over at least a portion of the substrate, forming a transistor over at least a portion of the oxide layer, and removing at least a portion of a backside of the substrate to form an opening providing radio-frequency isolation for the transistor.

Abstract: Aspects of this disclosure relate to a switching circuit with enhanced linearity. The switching circuit can include a switch and an envelope generator. The switch can receive an input signal, provide an output signal, and receive an envelope signal corresponding to an envelope of the input signal. The envelope generator can generate the envelope signal so as to cause intermodulation distortion in the output signal to be reduced to cause linearity of the switch to be improved.

Abstract: Field-effect transistor (FET) devices are described herein that include an insulator layer, a plurality of active field-effect transistors (FETs) formed from an active silicon layer implemented over the insulator layer, a substrate layer implemented under the insulator layer, and proximity electrodes for a plurality of the FETs that are each configured to receive a voltage and to generate an electric field between the proximity electrode and a region generally underneath a corresponding active FET. Switches with multiple FET devices having proximity electrodes are also disclosed.

Abstract: Field-effect transistor (FET) devices are described herein that include one or more body contacts implemented near source, gate, drain (S/G/D) assemblies to improve the influence of a voltage applied at the body contact on the S/G/D assemblies. For example, body contacts can be implemented between S/G/D assemblies rather than on the ends of such assemblies. This can advantageously improve body contact influence on the S/G/D assemblies while maintaining a targeted size for the FET device.