A 1.57 W/mm GaAs-based MISFET for high-power and microwave-switching applications

Reports the power and switching performance of a GaAs metal-insulator-semiconductor field-effect transistor (MISFET) made using low-temperature (LT) GaAs as the buffer layer and the gate insulator. An LT GaAs MISFET with a gate length L/sub g/ of 1.5 mu m delivered an output power density P/sub d/ of 1.57 W/mm with 4.4 dB gain and a power-added efficiency eta /sub PA/ of 27.3% at 1.1 GHz. This is the highest power density from a GaAs-based FET ever reported. The P/sub d/ and eta /sub PA/ of this device at 1.1 GHz are shown as a function of input power. More recently, the LT GaAs MISFET has also demonstrated switch performance at 1.3 GHz that is comparable to that of the best commercially available FET switches that the authors have tested.<>