Electrical Properties of Germanium Oxynitride and Its Interface with Germanium Prepared by Electron-Cyclotron-Resonance Plasma Oxidation and Nitridation

Abstract

We report on the electrical properties of germanium oxynitride and its interface with germanium prepared by nitriding the germanium oxide/germanium surface by irradiating a nitrogen plasma stream generated by an electron-cyclotron-resonance plasma source without substrate heating. Excellent leakage current characteristics were obtained for a metal–insulator–semiconductor capacitor with a gate stack consisting of a silicon nitride sputter-deposited on germanium oxynitride with an interface trap density of ~2×10¹¹ cm^-2eV^-1. Moreover, the equivalent oxide thickness of the germanium oxynitride was found to be about 30% smaller than that of germanium oxide. The reported germanium oxynitride is suitable as a beneficial interlayer between high-dielectric-constant gate insulators and germanium.