Characteristics of n-type SB-MOSFETs manufactured by using a metal-gate & a high-K dielectric

Abstract

We demonstrated n-type Schottky-barrier metal-oxide-semiconductor field-effect transistors (SB-MOSFETs) by using a low-temperature oxide dummy gate process to effectively form a high-k metal-gate structure. First, a MOS capacitor made a 5-nm-thick high-K dielectric with a tungsten electrode was fabricated. The equivalent oxide thickness and the flat-band voltage extracted by using a quantum-mechanical capacitance-voltage analysis were 1.69 nm and -0.15 V, respectively. A 2 mu m-gate-length n-type SB-MOSFETs with a source and a drain of erbium silicide showed a high on/off-current ratio of about 10(5) at a drain voltage of 1 V. The subthreshold swing and the saturation current were 81 mV/dec and 100 mu A/mu m, respectively.