Band bending measurement of HfO2/SiO2/Si capacitor with ultra-thin La2O3 insertion by XPS

The flat band voltage shifts of HfO(2)/SiO(2)/nSi capacitors with ultra-thin La(2)O(3) insertion at HfO(2)/SiO(2) interface have been confirmed using hard X-ray photoelectron spectroscopy (HX-PES). By increasing the amount of La(2)O(3) insertion, the binding energy of Si 1s core spectra increases, which means that the surface potential of Si substrate also increases. A voltage drop difference of HfO(2) and La(2)O(3) at SiO(2) interface can be estimated to be 0.40 V. (c) 2008 Elsevier B.V. All rights reserved.