Electrical characterization of La₂O₃-gated metal oxide semiconductor field effect transistor with mg incorporation

The effects of Mg incorporation into La₂O₃ dielectrics on the electrical characteristics of metal oxide semiconductor (MOS) capacitors and field effect transistors (FETs) have been examined. Large negative shifts in flat band voltage (V_fb) for capacitors and threshold voltage (V_th) for FETs observed at a small equivalent oxide thickness (EOT) of below 1.4 nm can be well suppressed with the incorporation of Mg. Moreover, interfacial state density (D_it) at a small EOT can be decreased as well. The effective mobility (μ_eff) evaluation revealed a large improvement, particularly at a low effective electric field (E_eff). This improvement is considered to be due to the suppression of remote Coulomb scattering in the gate oxide with Mg incorporation.