Optimizing the Ferroelectric Stack for Enhanced Performance of BEoL Integrated MFM Capacitors

Abstract—The hafnium oxide-based FeFET has generated great attention due to its good scalability, high operational speed, and low power consumption. However, the seamless integration into CMOS technologies poses significant challenges. A recent innovation, the 1T1C FeFET (also known as FeMFET), introduces a one-transistor (1T) configuration coupled with a separate ferroelectric capacitor (1C) within the BEoL, offering a promising solution. Notably, this approach enables integration into standard process technologies without requiring substantial changes at the transistor level. Nevertheless, the MFM capacitor plays a crucial role, serving as an essential component for the success of the FeMFET concept. This study conducts a comprehensive exploration of various stacks and integration schemes of the
BEoL MFM-module. The discussion delves into the impact of these stacks on crucial performance parameters, including remanent polarization, device-to-device variability, and imprint, shedding light on the development of next-generation FeMFET memory cells and arrays.