Improvement of GaAs metal–semiconductor field-effect transistor drain–source breakdown voltage by oxide surface passivation grown by atomic layer deposition

Oxide surface passivation grown by atomic layer deposition (ALD) has been applied to GaAs metal–semiconductor field-effect transistors (MESFETs). The breakdown characteristic of a MESFET is greatly improved by both Al2O3 and HfO2 passivation. Three-terminal transistor breakdown voltage is improved to a maximum level of 20 V with Al2O3 passivation from 11 V without any surface passivation. With the removal of native oxide and passivation on GaAs surface at drain–gate (D–G) and source–gate (S–G) spacings, the device breakdown characteristics are significantly improved. � 2005 Elsevier Ltd. All rights reserved.