High Field Characterization of Current-Voltage Dependences in Continuous/Semicontinuous High-k Ultrathin Films Through Leakage-Path Blocking

Abstract

We developed a ferroelectric assisted current-voltage characterization technique for continuous/semicontinuous high-k ultrathin films under the field as high as 17 MV/cm without invoking of dielectric breakdown. The leakage current of the ultrathin films equals domain switching current with breakdown paths blocked efficiently by underneath ferroelectric thick layer. The extracted field dependences of current density for a 1– 6 nm thick Al2O3 layer deposited on top of a 300 nm thick Pb(Zr,Ti)O3 layer obey the equation of Schottky mission. This technique is helpful for investigations of high-field charge emission and quantum physics for ultrathin films in loss of the atomic-layer flatness.