Enhancement of Transient Two-States Characteristics in Metal-Insulator-Semiconductor Structure by Thinning Metal Thickness

In this work, the Al/SiO2/p-Si metal-insulator-semiconductor structures with various metal thicknesses were fabricated. The charging/discharging transient current behaviors during sweeping or switching the voltages have been studied. By thinning down partial portion of the gate metal to 10 nm, the steady state leakage current was found decreased because the high resistivity of the ultrathin metal causing lower fringing field effect. Also, the transient currents were found enhanced. The reasons were that there were minority carriers under the ultrathin metal contributing to the transient currents. The above properties make the device having better volatile memory characteristics.