Comparative investigation on NH3-plasma treating different surfaces of stack-gate dielectric Ge MOS capacitors

Abstract

NH3-plasma treatment on different interfaces of stacked gate dielectric of HfGdON/LaTaON/Ge is carried out and the interfacial and electrical properties of the relevant Ge MOS capacitors are compared. Experimental results show that the NH3-plasma treatment on Ge surface results in superior interfacial and electrical properties. X-ray photoelectron spectroscopy analyses indicate that the NH3-plasma treatment on Ge surfaces could break Ge–O bonds to react with NH radicals, effectively resulting in the formation of GeOxNy, as well as suppression of Ge sub-oxides and passivation of dangling bonds at/near the stack dielectric/Ge interface.