Abstract
Self-aligned inversion-channel In 0.53 Ga 0.47 As n-MOSFETs with ex-situ atomic-layer-deposited Al 2 O 3 and in-situ ultra-high-vacuum deposited Al 2 O 3 /Ga 2 O 3 (Gd 2 O 3 ) as gate dielectrics have been demonstrated. Both devices exhibit excellent DC characteristics, including high drain currents and transconductances. In addition, RF characteristics of both devices were analyzed; without using any isolation, non de-embedded current gain cutoff frequency (f T ) and maximum oscillation frequency (f max ) of ∼ 3.1 and 1.1 GHz (ALD-Al 2 O 3 ) and of ∼ 17.9 and 11.2 GHz (MBE-Al 2 O 3 /Ga 2 O 3 (Gd 2 O 3 )), respectively, have been obtained. ©2009 IEEE.