Abstract: The present invention comprises a metal semiconductor field effect transistor (MESFET) 100. The MESFET 100 comprises a semiconductor substrate 110 composed of gallium arsenide (GaAs) which has a top surface. This MESFET transistor 100 further comprises a contiguous first conductivity type source area 165, gate area 164, and drain area 170 disposed near the top surface on the semiconductor substrate 110, wherein the source and drain areas 165 and 170 respectively are of an equal relatively large depth from the top surface with high doping concentration. The gate area 164 is of a relatively small depth from the top surface. The gate area 164 is further disposed between and extending thereunto the source area 165 and the drain area 170. The gate area 164 further includes a current enhancement region 155 being doped with ions of the first conductivity with relatively lower concentration and extending between the gate area 164 and the source area 165.

Abstract: The present invention discloses a phase shifting circuit for generating several output signals wherein each of the output signals maintaining a constant phase difference. The phase shifting circuit includes a first input port for receiving an input signal with a reference input phase. The phase shifting circuit further includes a second input port for receiving the input signal with a 180.degree. from the reference input phase. The phase shifting circuit has a first branch connected between the first and second input ports, the first branch including a first resistor-capacitor (RC) segment connected in series via a first mid-point to a second resistor-capacitor (RC) segment wherein the second RC segment is configured, with reference to the first mid-point, in complete mirror symmetry relative to the first RC segment. The phase shifting circuit further includes a second branch connected between the first and second input ports in parallel to the first branch.