Impact of Nitrogen Profile in Gate Oxynitride on Complementary Metal Oxide Semiconductor Characteristics

We demonstrated that the control of the nitrogen profile in the gate oxynitride for complementary metal oxide semiconductors (CMOSs) is very important. We grew NO or N2O nitrided gate oxide at 800°C or 900°C to prepare three kinds of oxynitrides with different nitrogen profiles, and investigated the atomic configuration and the chemical state of nitrogen using secondary ion mass spectroscopy and X-ray photoelectron spectroscopy. Furthermore, we fabricated CMOS field effect transistors with gate oxide and oxynitride, and evaluated the interface state density and the hot carrier immunity. By systematical investigation of the relationship between the nitrogen profile and the electrical characteristics, we found that the nitrogen in the oxynitride should exist only at the interface for realizing the CMOS devices having high performance and high reliability.