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

Abstract

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 NH3 plasma interfacial layer (IL) treatment and microwave annealing (MWA). An orthorhombic crystalline phase is observed in the annealed HZO film with NH3 plasma IL treatment and MWA, and NH3 plasma IL treatment can suppress Hf/Zr interdiffusion. Metal-oxide-semiconductor capacitors (MOSCAPs) subjected to NH3 plasma 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 compared to the devices subjected to only rapid thermal annealing (RTA) at 600 degrees C. Therefore, NH3 plasma treatment and MWA are effective for improving the TDDB reliability and interface quality of the ultrathin ferroelectric HZO.