Electronic structure of silicon oxynitride: Ab-initio and experimental study, comparison with silicon nitride

Amorphous silicon oxide SiO(2), silicon nitride Si(3)N(4), and silicon oxynitride SiO(x)N(y) are three key dielectrics in silicon devices. Implementation of nitrided oxide (oxynitride SiO(x)N(y)) as a gate dielectric in metal-oxide-semiconductor field effect transistors has been shown to significantly improve the reliability and lifetime of devices. Also, amorphous oxynitride is used as a tunnel dielectric in nonvolatile flash memory devices. The present paper is devoted to the experimental and theoretical study of silicon oxynitride electronic structure. The ionic formula of crystalline Si(2)N(2)O is deduced from the first principles. Effective masses of charge carriers in Si(2)N(2)O are calculated and compared with experimental data on tunnel injection in amorphous SiN(x)O(y) samples. Also experimental x-ray absorption and emission spectra are compared with the theoretically calculated ones. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3653833]