A Half-Micron Gate Low Noise GaAs MESFET and Amplifiers

A half-micron gate GaAs MESFET is designed and fabricated for the minimum gate parasitics. The single bonding-pad design of the gate and intentional side-etching of the lower layer of the double-layered Schottky-gate satisfy the above requirement. The best noise figure so far measured is 2.5 dB at 10 GHz for the packaged device and 2.1 dB at 12 GHz for the chip device. An X-band unit amplifier is designed for the FET chip. It can be cascaded to get a specified power gain or modified to have a necessary bandwidth.