The effects of hydrogen and deuterium incorporation on the electrical performance of a GaAs MESFET

A commercial GaAs MESFET annealed in 5% hydrogen showed shifts in its turn-on voltage and degradation in both its transconductance and drain current. Annealing in deuterium showed similar, though less extensive behavior, indicating that deuterium diffuses into the devices slower than hydrogen. A thin film diffusion experiment showed that the incorporation of hydrogen into the gate area is greatest when platinum is exposed to the hydrogen. Provides supporting evidence that diffusion of hydrogen occurs at the Pt sidewalls and not at the Au surface of the Au/Pt/Ti gate metal.