Resonant tunneling in stacked dielectrics: A novel approach for obtaining the electron tunneling mass-conduction band offset energy products for advanced gate dielectrics
Contributors: C.L. Hinkle, C. Fulton, R.J. Nemanich, and G. Lucovsky
ABSTRACT
There has been a search for alternative dielectrics with significantly increased dielectric constants, k, which increases in physical thickness proportional to k, and therefore would significantly reduce direct tunneling. However, increases in k to values of 15 to 25 in transition metal and rare earth oxides are generally accompanied by decreases in the conduction band offset energy, EB, with respect to Si, and in the effective electron tunneling mass, Meff, which mitigate gains from increased thickness. A novel technique, based on stacked dielectrics, is used to obtain the tunneling mass-conduction band offset energy product. When combined with spectroscopic estimates of tunneling barriers, this yields values for the tunneling mass.