ABSTRACT
GaAs FETs’ anomalous frequency dispersion can be observed clearly with large-signal direct I-V measurement, which can emphasize rate-dependent and/or field-dependent phenomena causing such dispersion. GaAs MESFETs showed behavior specific to structures, such as drain current decrease and drain conductance increase at high frequencies. Characterization and consideration of mechanism for buried p-layer GaAs MESFETs and that with low-temperature buffer layer are presented. Frequency dispersion was apparent in the device with low-temperature buffer. As there proved to be shifts in threshold voltage, such frequency dispersion may be attributed to phenomena related to electron traps in channel-buffer interface.
