Ultrathin Ferroelectric Nondoped HfO2 for MFSFET with High-speed and Low-voltage Operation

Abstract

Ferroelectric nondoped HfO2 has been investigated for metal-ferroelectric-semiconductor field-effect transistor (MFSFET) application due to the low crystallization temperature and the suppression of SiO2 interfacial layer (IL) formation between HfO2 and Si substrate. We realized MFSFET with the scaling of ferroelectric gate insulator utilizing 5 nm thick nondoped HfO2, and the ferroelectric property was improved by decreasing the sputtering damage of Pt gate electrode deposition [1]. However, the low frequency noise affected by interfacial property of MFSFET becomes important, especially for scaled device [2]. In this research, we investigated the effects of sputtering power for 5 nm thick HfO2 gate insulator formation to realize high-speed operation of MFSFET.