Improved TDDB Reliability and Interface States in 5-nm Hf0.5Zr0.5O2 Ferroelectric Technologies Using NH3 Plasma and Microwave Annealing

This article reports that the enhanced forward gate bias time-dependent dielectric breakdown (TDDB) reliability and interface quality are achieved in 5-nm ferroelectric Hf0.5Zr0.5O2(HZO) technologies by using the NH3plasma interfacial layer (IL) treatment and microwave annealing (MWA). An orthorhombic crystalline phase is observed in the annealed HZO film with NH3plasma IL treatment and MWA, and NH3plasma IL treatment can suppress Hf/Zr interdiffusion. Metal-oxide-semiconductor capacitors (MOSCAPs) subjected to NH3plasma IL treatment and 2100-W MWA also have a higher extrapolated operating voltage for a ten-year lifetime at 0.01% failure and lower interface state density (Dit) compared to the devices subjected to only rapid thermal annealing (RTA) at 600 °C. Therefore, NH3plasma treatment and MWA are effective for improving the TDDB reliability and interface quality of the ultrathin ferroelectric HZO.