Leakage Current Suppression in Spatially Controlled Si doped ZrO2 for Capacitor using Atomic Layer Deposition

Abstract

Among various high-k materials, zirconium dioxide (ZrO2) has attracted considerable attention due to its high dielectric constant and wide band gap. However, its main disadvantage is its large leakage current. Doping ZrO2 with silicon has been proposed as a solution to this issue. In this study, we investigated the current mechanism and electronic structure of Si-doped ZrO2 thin films. We used atomic layer deposition (ALD) to deposit Si-doped ZrO2 thin films. This method has many advantages such as excellent step coverage, low process temperature, and high film quality. We found that proper Si doping, which affects Si distribution in the ZrO2 and therefore its electronic band structure, is necessary for leakage current reduction.