Abstract: A radio frequency (RF) switch includes a heating element, thermally conductive and electrically insulating layer over the heating element, a wetting dielectric layer over the thermally conductive and electrically insulating layer, and a phase-change material (PCM) over the wetting dielectric layer. At least one cladding dielectric layer can be situated over sides and/or over a top surface of the PCM. Each of the wetting dielectric layer, phase change material, and cladding dielectric layer can comprise at least germanium. A transitional dielectric layer can be situated between the thermally conductive and electrically insulating layer and the wetting dielectric layer. A contact uniformity support layer can be situated over the cladding dielectric layer.

Abstract: In fabricating a radio frequency (RF) switch, a heat spreader is provided and a heating element is deposited. A thermally conductive and electrically insulating material is deposited over the heating element. The heating element and the thermally conductive and electrically insulating material are patterned, where the thermally conductive and electrically insulating material is self-aligned with the heating element. A layer of an upper dielectric is deposited. A conformability support layer is optionally deposited over the upper dielectric and the thermally conductive and electrically insulating material. A phase-change material is deposited over the optional conformability support layer and the underlying upper dielectric and the thermally conductive and electrically insulating material.

Abstract: A radio frequency (RF) switch includes a phase-change material (PCM), a heating element underlying an active segment of the PCM and extending outward and transverse to the PCM, and RF terminals having lower metal portions and upper metal portions. At least one of the lower metal portions can be ohmically separated from and capacitively coupled to passive segments of the PCM, while the upper metal portions are ohmically connected to the lower metal portions. Alternatively, the lower metal portions can be ohmically connected to passive segments of the PCM, while a capacitor is formed in part by at least one of the upper metal portions. Alternatively, at least one of the RF terminals can have a trench metal liner separated from a trench metal plug by a dielectric liner. The trench metal liner can be ohmically connected to passive segments of the PCM, while the trench metal plug is ohmically separated from, but capacitively coupled to, the trench metal liner.

Abstract: In fabricating a radio frequency (RF) switch, a phase-change material (PCM) and a heating element, underlying an active segment of the PCM and extending outward and transverse to the PCM, are provided. Lower portions of PCM contacts for connection to passive segments of the PCM are formed, wherein the passive segments extend outward and are transverse to the heating element. Upper portions of the PCM contacts are formed from a lower interconnect metal. Heating element contacts are formed cross-wise to the PCM contacts. The heating element contacts can comprise a top interconnect metal directly connecting with terminal segments of the heating element. The heating element contacts can comprise a top interconnect metal and intermediate metal segments for connecting with the terminal segments of the heating element.

Abstract: A capacitive tuning circuit includes radio frequency (RF) switches connected to an RF line. Each RF switch includes a phase-change material (PCM), a heating element underlying an active segment of the PCM and extending outward and transverse to the PCM, and RF terminals having lower metal portions and upper metal portions. Alternatively, the RF terminals can have a trench metal liner separated from a trench metal plug by a dielectric liner. At least one capacitor is formed in part by at least one of the lower metal portions, upper metal portions, or trench metal liner. The capacitive tuning circuit can be set to a desired capacitance value when a first group of the RF switches is in an OFF state and a second group of the RF switches is in an ON state.

Abstract: A radio frequency (RF) switch includes a heating element, an aluminum nitride layer situated over the heating element, and a phase-change material (PCM) situated over the aluminum nitride layer. An inside segment of the heating element underlies an active segment of the PCM, and an intermediate segment of the heating element is situated between a terminal segment of the heating element and the inside segment of the heating element. The aluminum nitride layer situated over the inside segment of the heating element provides thermal conductivity and electrical insulation between the heating element and the active segment of the PCM. The aluminum, nitride layer extends into the intermediate segment of the heating element and provides chemical protection to the intermediate segment of the heating element, such that the intermediate segment of the heating element remains substantially unetched and with substantially same thickness as the inside segment.

Abstract: In fabricating a radio frequency (RF) switch, a phase-change material (PCM) and a heating element, underlying an active segment of the PCM and extending outward and transverse to the PCM, are provided. Lower portions of PCM contacts for connection to passive segments of the PCM are formed, wherein the passive segments extend outward and are transverse to the heating element. Upper portions of the PCM contacts are formed from a lower interconnect metal. Heating element contacts are formed cross-wise to the PCM contacts. The heating element contacts can comprise a top interconnect metal directly connecting with terminal segments of the heating element. The heating element contacts can comprise a top interconnect metal and intermediate metal segments for connecting with the terminal segments of the heating element.

Abstract: A radio frequency (RF) switch includes a phase-change material (PCM) and a heating element underlying an active segment of the PCM, the PCM and heating element being situated over a substrate. A contact dielectric is over the PCM. PCM contacts have upper portions and uniform plate slot lower portions. The uniform plate slot lower portions have a total plate resistance RPLATE, and a total plate slot interface resistance RPLATE-INT. The upper portions have a total capacitance CUPPER to the uniform plate slot lower portions, and the PCM has a total capacitance CPCM to the substrate. The uniform plate slot lower portions significantly reduce a product of (RPLATE+RPLATE-INT) and (CUPPER+CPCM). As an alternative to the uniform plate slot lower portions, PCM contacts have segmented lower portions. The segmented lower portions significantly reduce CUPPER.

Abstract: A radio frequency (RF) switch includes a phase-change material (PCM) and a heating element underlying an active segment of the PCM, the PCM and heating element being situated over a substrate. A contact dielectric is over the PCM. PCM contacts have upper portions and uniform plate slot lower portions. The uniform plate slot lower portions have a total plate resistance RPLATE, and a total plate slot interface resistance RPLATE-INT. The upper portions have a total capacitance CUPPER to the uniform plate slot lower portions, and the PCM has a total capacitance CPCM to the substrate. The uniform plate slot lower portions significantly reduce a product of (RPLATE+RPLATE-INT) and (CUPPER+CPCM). As an alternative to the uniform plate slot lower portions, PCM contacts have segmented lower portions. The segmented lower portions significantly reduce CUPPER.

Abstract: A radio frequency (RF) switch includes a stressed phase-change material (PCM) and a heating element underlying an active segment of the stressed PCM and extending outward and transverse to the stressed PCM. In one approach, at least one transition layer is situated over the stressed PCM. An encapsulation layer is situated over the at least one transition layer and on first and second sides of the stressed PCM. A stressor layer is situated over the encapsulation layer and the said stressed PCM. Alternatively or additionally, contacts of the RF switch extend into passive segments of a PCM, wherein adhesion layers adhere the passive segments of the PCM to the contacts.

Abstract: In fabricating a radio frequency (RF) switch, a phase-change material (PCM) and a heating element, underlying an active segment of the PCM and extending outward and transverse to the PCM, are provided. Lower portions of PCM contacts for connection to passive segments of the PCM are formed, wherein the passive segments extend outward and are transverse to the heating element. Upper portions of the PCM contacts are formed from a lower interconnect metal. Heating element contacts are formed cross-wise to the PCM contacts. The heating element contacts can comprise a top interconnect metal directly connecting with terminal segments of the heating element. The heating element contacts can comprise a top interconnect metal and intermediate metal segments for connecting with the terminal segments of the heating element.

Abstract: In fabricating a radio frequency (RF) switch, a phase-change material (PCM) and a heating element, underlying an active segment of the PCM and extending outward and transverse to the PCM, are provided. Lower portions of PCM contacts for connection to passive segments of the PCM are formed, wherein the passive segments extend outward and are transverse to the heating element. Upper portions of the PCM contacts are formed from a lower interconnect metal. Heating element contacts are formed cross-wise to the PCM contacts. The heating element contacts can comprise a top interconnect metal directly connecting with terminal segments of the heating element. The heating element contacts can comprise a top interconnect metal and intermediate metal segments for connecting with the terminal segments of the heating element.

Abstract: A heterojunction bipolar transistor (HBT) is fabricated using a selectively implanted collector (SIC) implant mask including multiple openings located over the HBT's collector region. During the SIC implant process, resist mask edge (well proximity) effects caused by the SIC dopant passing through the multiple openings generates multiple secondary shallow increased-doping regions in the collector region adjacent to the substrate surface, where the mask openings are sized such that each secondary increased-doping region has a doping concentration that is comparable to primary increased-doping regions, which are simultaneously formed deeper in the SIC region. A base structure and an emitter structure are then formed over the SIC region using known techniques. The secondary increased-doping regions produce enhanced base-collector junction between the SIC region and the base structure that measurably decreases Kirk Effect by way of enhancing the HBT's cutoff frequency (Ft) and break-down voltage (BVCEO).

Abstract: A radio frequency (RF) switch includes a phase-change material (PCM), a heating element underlying an active segment of the PCM and extending outward and transverse to the PCM, and RF terminals having lower metal portions and upper metal portions. At least one of the lower metal portions can be ohmically separated from and capacitively coupled to passive segments of the PCM, while the upper metal portions are ohmically connected to the lower metal portions. Alternatively, the lower metal portions can be ohmically connected to passive segments of the PCM, while a capacitor is formed in part by at least one of the upper metal portions. Alternatively, at least one of the RF terminals can have a trench metal liner separated from a trench metal plug by a dielectric liner. The trench metal liner can be ohmically connected to passive segments of the PCM, while the trench metal plug is ohmically separated from, but capacitively coupled to, the trench metal liner.

Abstract: A semiconductor structure includes a semiconductor mesa situated on a semiconductor substrate, a trap-rich region comprising polycrystalline silicon adjacent to the semiconductor mesa, and a phase-change material (PCM) radio frequency (RF) switch. A heating element of the PCM RF switch is situated over the semiconductor mesa. An interconnect segment coupled to the PCM RF switch is situated over the trap-rich region. Alternatively, a semiconductor structure can include a trap-rich region adjacent to a single crystal region of the semiconductor substrate, where the trap-rich region is formed by implant damaging, and where the heating element of the PCM RF switch is situated over the single crystal region.

Abstract: In a method for wafer-to-wafer bonding, an integrated circuit (IC) wafer and a phase-change material (PCM) switch wafer are provided. The IC includes at least one active device, and has an IC substrate side and a metallization side. The PCM switch wafer has a heat spreading side and a radio frequency (RF) terminal side. A heat spreader is formed in the PCM switch wafer. In one approach, the heat spreading side of the PCM switch wafer is bonded to the metallization side of the IC wafer, then a heating element is formed between the heat spreader and a PCM in the PCM switch wafer. In another approach, a heating element is formed between the heat spreader and a PCM in the PCM switch wafer, then the RF terminal side of the PCM switch wafer is bonded to the metallization side of the IC wafer.

Abstract: A radio frequency (RF) switch includes a heating element, a nugget, a phase-change material (PCM), and input/output contacts. The nugget comprises thermally conductive and electrically insulating material, and is situated on top of the heating element. The PCM has an active segment approximately situated over the nugget, and passive segments approximately situated under the input/output contacts. The PCM RF switch may include thermally resistive material adjacent to first and second sides of the heating element, and/or adjacent to first and second sides of the nugget. The PCM RF switch may include a heat valve under the heating element.

Abstract: A rapid testing read out integrated circuit (ROIC) includes phase-change material (PCM) radio frequency (RF) switches residing on an application specific integrated circuit (ASIC). Each PCM RF switch includes a PCM and a heating element transverse to the PCM. The ASIC is configured to provide amorphizing and crystallizing electrical pulses to a selected heating element in a selected PCM RF switch. The ASIC is also configured to generate data for determining and characterizing resistivity change of the selected heating element in the selected PCM RF switch after the ASIC performs a plurality of OFF/ON cycles. In one implementation, a testing method using the ASIC is disclosed.

Abstract: In fabricating a semiconductor device, a shared material is formed in a resonator region of the semiconductor device and in a phase-change material (PCM) switch region of the semiconductor device. A portion of the shared material is removed to concurrently form a heat spreader comprising the shared material in the PCM switch region and a piezoelectric segment comprising the shared material in the resonator region. The piezoelectric segment in the resonator region and the heat spreader in the PCM switch region are situated at substantially the same level in the semiconductor device. The PCM switch region includes a heating element between the heat spreader and a PCM. The resonator region includes the piezoelectric segment between two electrodes.

Abstract: A rapid testing read out integrated circuit (ROIC) includes phase-change material (PCM) radio frequency (RF) switches residing on an application specific integrated circuit (ASIC). Each PCM RF switch includes a PCM and a heating element transverse to the PCM. The ASIC is configured to provide amorphizing and crystallizing electrical pulses to a selected PCM RF switch. The ASIC is also configured to generate data for determining and characterizing OFF state conductivity skew and ON state conductivity skew of the PCM in the selected PCM RF switch after the ASIC performs a plurality of OFF/ON cycles. In one implementation, a testing method using the ASIC is disclosed.