Gallium-arsenide E- and D-MESFET device noise characteristics operated at cryogenic temperatures with ultralow drain current

The low-frequency noise characteristics of GaAs MESFETs operating at very low power and at cryogenic temperatures of 77 and 10 K as well as at room temperature are discussed. A self-aligned gate and a buried p-layer were incorporated to maximize device gain and minimize low-frequency noise. Measurements at 77 K show a noise voltage spectral density of 1.0-2.0 mu V/ square root Hz at 1.0 Hz (referred to the transistor input) with a drain current of 1.0 mu A.<
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