Abstract: An apparatus includes a substrate; a group III-Nitride barrier layer; a source electrically coupled to the group III-Nitride barrier layer; a gate on the group III-Nitride barrier layer; a drain electrically coupled to the group III-Nitride barrier layer; a p-region being arranged at or below the group III-Nitride barrier layer; and a recovery enhancement circuit configured to reduce an impact of an overload received by the gate. Additionally, at least a portion of the p-region is arranged vertically below at least one of the following: the source, the gate, an area between the gate and the drain.

Abstract: An apparatus includes a substrate; a group III-Nitride barrier layer; a source electrically coupled to the group III-Nitride barrier layer; a gate on the group III-Nitride barrier layer; a drain electrically coupled to the group III-Nitride barrier layer; a p-region being arranged at or below the group III-Nitride barrier layer; and a recovery enhancement circuit configured to reduce an impact of an overload received by the gate. Additionally, at least a portion of the p-region is arranged vertically below at least one of the following: the source, the gate, an area between the gate and the drain.

Abstract: An apparatus for reducing lag includes a substrate; a group III-Nitride barrier layer; a source electrically coupled to the group III-Nitride barrier layer; a gate on the group III-Nitride barrier layer; a drain electrically coupled to the group III-Nitride barrier layer; a p-region being arranged at or below the group III-Nitride barrier layer; and a gate control circuit configured to control a gate voltage of the gate. Additionally, at least a portion of the p-region is arranged vertically below at least one of the following: the source, the gate, and an area between the gate and the drain.

Abstract: Monolithic microwave integrated circuits are provided that include a substrate, a transmit/receive selection device that is formed on the substrate, a high power amplifier formed on the substrate and coupled to a first RF port of the transmit/receive selection device, a low noise amplifier formed on the substrate and coupled to a second RF port of the transmit/receive selection device and a protection circuit that is coupled to a first control port of the transmit/receive selection device.

Abstract: Monolithic microwave integrated circuits are provided that include a substrate, a transmit/receive selection device that is formed on the substrate, a high power amplifier formed on the substrate and coupled to a first RF port of the transmit/receive selection device, a low noise amplifier formed on the substrate and coupled to a second RF port of the transmit/receive selection device and a protection circuit that is coupled to a first control port of the transmit/receive selection device.

Abstract: Monolithic microwave integrated circuits are provided that include a substrate, a transmit/receive selection device that is formed on the substrate, a high power amplifier formed on the substrate and coupled to a first RF port of the transmit/receive selection device, a low noise amplifier formed on the substrate and coupled to a second RF port of the transmit/receive selection device and a protection circuit that is coupled to a first control port of the transmit/receive selection device.

Abstract: Monolithic microwave integrated circuits are provided that include a substrate, a transmit/receive selection device that is formed on the substrate, a high power amplifier formed on the substrate and coupled to a first RF port of the transmit/receive selection device, a low noise amplifier formed on the substrate and coupled to a second RF port of the transmit/receive selection device and a protection circuit that is coupled to a first control port of the transmit/receive selection device.

Abstract: A monolithic high power radio frequency switch includes a substrate, and first and second gallium nitride high electron mobility transistors on the substrate. Each of the first and second gallium nitride high electron mobility transistors includes a respective source, drain and gate terminal. The source terminal of the first gallium nitride high electron mobility transistor is coupled to the drain terminal of the second gallium nitride high electron mobility transistor, and the source terminal of the second gallium nitride high electron mobility transistor is coupled to ground. An RF input pad is coupled to the drain terminal of the first second gallium nitride high electron mobility transistor, an RF output pad is coupled to the source terminal of the first gallium nitride high electron mobility transistor and the drain terminal of the second gallium nitride high electron mobility transistor, and a control pad is coupled to the gate of the first gallium nitride high electron mobility transistor.

Abstract: A diode structure having a reduced on-resistance in the forward-biased condition includes semiconductor layers, preferably of silicon carbide. The anode and cathode of the device are located on the same side of the bottom semiconductor layer, providing lateral conduction across the diode body. The anode is positioned on a semiconductor mesa, and the sides of the mesa are covered with a nonconductive spacer extending from the anode to the bottom layer. An ohmic contact, preferably a metal silicide, covers the surface of the bottom layer between the spacer material and the cathode. The conductive path extends from anode to cathode through the body of the mesa and across the bottom semiconductor layer, including the ohmic contact. The method of forming the diode includes reacting layers of silicon and metal on the appropriate regions of the diode to form an ohmic contact of metal silicide.

Abstract: A monolithic high power radio frequency switch includes a substrate, and first and second gallium nitride high electron mobility transistors on the substrate. Each of the first and second gallium nitride high electron mobility transistors includes a respective source, drain and gate terminal. The source terminal of the first gallium nitride high electron mobility transistor is coupled to the drain terminal of the second gallium nitride high electron mobility transistor, and the source terminal of the second gallium nitride high electron mobility transistor is coupled to ground. An RF input pad is coupled to the drain terminal of the first second gallium nitride high electron mobility transistor, an RF output pad is coupled to the source terminal of the first gallium nitride high electron mobility transistor and the drain terminal of the second gallium nitride high electron mobility transistor, and a control pad is coupled to the gate of the first gallium nitride high electron mobility transistor.

Abstract: An electronically steerable antenna array which includes time delay units connected to individual antenna elements for time delaying a microwave signal to and/or from the antenna elements. Each time delay unit includes small mercury wetted switches for controlling signal flow via a time delay path or a bypass path, through the time delay unit from a signal input to a signal output.

Abstract: A switch having spaced apart conductors with a high resistivity gate member therebetween. First and second mercury droplets are respectively connected to the ends of the conductors. When a control signal is applied to the gate member, the mercury droplets are drawn to it and establish electrical connection between the conductors to close the switch. Upon removal of the control signal the mercury droplets separate and assume their initial droplet form thus opening the switch.

Abstract: X-band signals are generated from the output of a Josephson junction array which is excited by a first RF frequency waveform digitally implemented in a data stream generated by a digital waveform generator gated by a stabilized local oscillator operating at a second frequency (X-band). The Josephson junction array outputs a digital data stream having pulses of quantum mechanically accurate uniform amplitude and picosecond pulsewidth. These pulses are fed to a bandpass filter which operates to extract a low phase-noise RF signal at X-band and consisting of the sum of the first and second frequencies and which can thereafter be used to generate transmit signals in a radar system and more particularly a cryogenic radar system.

Abstract: A silicon-based monolithic microwave integrated circuit architecture is described. This architecture, called MICROX.TM., is a combination of silicon material growth and wafer processing technologies. A wafer is fabricated using a substrate of high resistivity silicon material. An insulating layer is formed in the wafer below the surface area of active silicon, preferably using the SIMOX process. A monolithic circuit is fabricated on the wafer. A ground plane electrode is formed on the back of the wafer. Direct current and rf capacitive losses under microstrip interconnections and transistor source and drain electrodes are thereby minimized. Reduction in the resistivity of the substrate material as a result of CMOS processing can be minimized by maintaining a shielding layer over the bottom surface of the wafer. Microstrip and airbridge connectors, salicide processing and nitride side wall spacing can be used to further enhance device performance.

Abstract: A cell-type atomic frequency standard utilizing a miniaturized gas cell and microwave exciter along with a diode laser light source. The intensity of the diode laser light source counterbalances the penalties associated with the small gas cell. The signal produced by an oscillator is applied to a vapor within the gas cell by a miniature helix coil, or LC gap conductor, or a microstrip exciter. With the dimensions of the gas cell not exceeding one-half the wavelength of the signal, and the associated circuitry formed on a semiconductor substrate, the resulting frequency standard is reduced in size by two orders of magnitude when compared to prior art devices of comparable accuracy.