The electrical and interfacial properties of metal-high-κ oxide-semiconductor field effect transistors with CeO_2/HfO_2 laminated gate dielectrics

摘要

Metal-oxide-semiconductor field-effect transistors with CeO_2/HfO_2 laminated gate dielectrics were fabricated. The transistors have a subthreshold slope of 74.9 mV/decade. The interfacial properties were measured using gated diodes. The surface state density D_(it) was 9.78 × 10~(11) cm~(-2) eV~(-1). The surface-recombination velocity (s_0) and the minority carrier lifetime in the field-induced depletion region (τ_(0,FU)) measured from the gated diode were about 6.11 ×10~3cm/s and 1.8 × 10~(-8) s, respectively. The effective capture cross section of surface state (σ_s) extracted using the subthreshold-swing measurement and the gated diode was about 7.69 × 10~(-15) cm~2. The effective electron mobility of CeO_2/HfO_2 laminated gated transistors was determined to be 212 cm~2/V s.