Low-noise GaAs field-effect transistors prepared by molecular beam epitaxy

The noise performance of ’’T’’ shaped Ti/W/Au gate GaAs Schottky-barrier field-effect transistors (FET’s) fabricated on channel layers grown by molecular beam epitaxy (MBE) is reported. The nominal gate length was about 0.7 μm with a total gate width of 250 μm. Typical noise figures and the associated gains at room temperature were 1.2 and 14 dB at 4 GHz, and 1.9 and 8.5 dB at 12 GHz. To our knowledge, these are the best results reported to date by MBE. These preliminary results, while not reaching the state of the art, do show the promise of MBE for high-quality GaAs FET’s.