Thermal stability of ALD HfO2 thin films and interfacial layers on the oxynitride underlayer formed using remote plasma

Abstract

Small amounts of N atoms were successfully incorporated by remote nitrogen plasma treatment into an oxynitride underlayer for the growth of an atomic layer deposited (ALD) HfO2 thin film. As the electron density and emission intensity of nitrogen plasma increased with plasma power, the concentration of incorporated N atoms increased. The dominant emission species in the N-2 plasma were excited atomic nitrogen (N-*) and excited molecular nitrogen (N-2(*)). Due to the oxynitride layer, the growth of the interfacial layer in HfO2 films was effectively suppressed, the crystallization temperature of HfO2 films increased, and the electrical properties were improved.