Abstract: A varactor comprising a substrate of semiconductor material on which is grown both an electrostatic barrier having a first layer of material doped with donor impurities and a second layer of material doped with acceptor impurities and a depletable layer. In other embodiments of the present invention varactors are provided that include a plurality of barrier and depletable layer pairs grown in a serial arrangement.

Abstract: An amplifier including an amplifying transistor flip-mounted on a coplanar waveguide pattern. Elements of stability and/or matching circuits are provided at least in part under the flip-mounted transistor to facilitate compact design and to improve component performance. A serial resistor-shunt inductor pair is provided with the resistor coupled proximate the transistor input and/or output and preferably configured within the CPW center conductor to provided more consistent component values. Embodiments of the present invention include a two-stage amplifier having a transmission segment formed between the two stages which serves to rotate the output impedance of the first stage toward a low noise match with the second stage and to rotate the input impedance of the second stage toward a high gain match with the first stage. The transmission segment may include a capacitive element for providing series capacitance and DC blocking. Adjustable impedance matching means are also taught.

Abstract: A process of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted to a circuit motherboard having large passive elements. A push-pull amplifier is presented as an example in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. The electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of striplines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide.

Abstract: A radio-frequency power amplifier includes a multiple-FET chip that is flip mounted on a connection region of a substrate. An input impedance-matching network is also mounted on the substrate. The network includes a coplanar waveguide having an elongate waveguide signal conductor for each gate terminal on the FET chip with a distal end spaced from the connection region and a proximal end in the connection region. The distal ends are connected to a single base input conductor. The proximal ends are flip mounted to respective ones of gate terminals of the FET chip. A capacitor couples each of the input signal conductor distal ends to an adjacent ground conductor. The signal conductors and capacitors provide a selected impedance at a selected frequency. The capacitors may be on a separate chip flip mounted to the waveguide signal and ground conductors, and may be formed as coplanar waveguides with open-ended signal conductors.

Abstract: A means of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted to a circuit motherboard having large passive elements. A push-pull amplifier is presented as an example in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. The electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of striplines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide.

Abstract: A means of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted to a circuit motherboard having large passive elements. A push-pull amplifier is presented as an example in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. The electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of striplines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide. In particular, a conversion of a split coplanar slotline to dual coplanar waveguides provides signal transmission to a pair of transistors flip-mounted onto the coplanar waveguides.

Abstract: An asymmetric reentrant power coupler suitable for microwave and millimeter bands that includes k input terminals, a plurality of m output terminals, where m is greater than k, and a network coupling the k input terminals to the m output terminals, the network defining n signal paths, where n is greater that m. An input coupler divides an input signal into at least two signal paths. An output coupler recombines a fraction less than one of the divided input signal for propagation to an output terminal. A portion of the non-recombined input signal is propagated to another output terminal. The reentrant coupler may be implemented using Wilkinson, ring, branched line or other coupler types. Couplers that are generally planar as well as coupler that are non-planar are presented.

Abstract: An active device, such as a field effect transistor ("FET") or MMIC, converts microwave signals between a microstrip transmission line ("microstrip") and a coplanar wave guide ("CPW"). In microstrip-to-CPW conversion using a simple FET, a gate connection is made to the microstrip signal conductor. A drain connection is made to the center conductor on the CPW. Two FET source terminals are connected respectively to each CPW ground strip. The ground strips are electrically coupled to the microstrip ground plane with a minimum length connection so the inductance common to the FET input and output is minimized. The FET can be reconnected so as to reverse the input and output, providing for conversion of signals from CPW to microstrip. Conversion from microstrip to an intermediate CPW and back to microstrip provides for mounting an intermediate circuit, such as an amplifier or other MMIC, directly on the CPW.

Abstract: A radio-frequency power amplifier includes a multiple-FET chip that is flip mounted on a connection region of a substrate. An input impedance-matching network is also mounted on the substrate. The network includes a coplanar waveguide having an elongate waveguide signal conductor for each gate terminal on the FET chip with a distal end spaced from the connection region and a proximal end in the connection region. The distal ends are connected to a single base input conductor. The proximal ends are flip mounted to respective ones of gate terminals of the FET chip. A capacitor couples each of the input signal conductor distal ends to an adjacent ground conductor. The signal conductors and capacitors provide a selected impedance at a selected frequency. The capacitors may be on a separate chip flip mounted to the waveguide signal and ground conductors, and may be formed as coplanar waveguides with open-ended signal conductors.

Abstract: An active device, such as a field effect transistor ("FET") or MMIC, converts microwave signals between a microstrip transmission line ("microstrip") and a coplanar wave guide ("CPW"). In microstrip-to-CPW conversion using a simple FET, a gate connection is made to the microstrip signal conductor. A drain connection is made to the center conductor on the CPW. Two FET source terminals are connected respectively to each CPW ground strip. The ground strips are electrically coupled to the microstrip ground plane with a minimum length connection so the inductance common to the FET input and output is minimized. The FET can be reconnected so as to reverse the input and output, providing for conversion of signals from CPW to microstrip. Conversion from microstrip to an intermediate CPW and back to microstrip provides for mounting an intermediate circuit, such as an amplifier or other MMIC, directly on the CPW.