Abstract
The spatial distribution of chemical elements is studied in high-kappa, metal-gated stacks applied in field effect transistors. Using the transmission electron microscope (TEM)-based analytical techniques electron energy-loss spectroscopy (EELS) and energy-dispersive x-ray spectroscopy, it is demonstrated that Al(2)O(3) and La(2)O(3) capping layers show distinctly different diffusion profiles. The importance of the EELS collection angle is discussed. Popular chemical distribution models that assume La-rich interface layers are rejected. (c) 2010 American Institute of Physics. [doi:10.1063/1.3478446]