Chemical states and electronic structure of a HfO(-2) / Ge(001) interface

Seo, Kang-ill ; McIntyre, Paul C. ; /Stanford U., Materials Sci. Dept. ; Sun, Shiyu ; Lee, Dong-Ick ; Pianetta, Piero ; /SLAC, SSRL ; Saraswat, Krishna C. ; /Stanford U., Elect. Eng. Dept.

Stanford Linear Accelerator Center

关键词: Chemical State;    Electronic Structure;    Spectra;    Fermi Level;    43 Particle Accelerators;   

DOI  :  10.2172/890919
RP-ID  :  SLAC-PUB-11049
RP-ID  :  AC02-76SF00515
RP-ID  :  890919

美国|英语

来源: UNT Digital Library

【 摘 要 】

We report the chemical bonding structure and valence band alignment at the HfO{sub 2}/Ge (001) interface by systematically probing various core level spectra as well as valence band spectra using soft x-rays at the Stanford Synchrotron Radiation Laboratory. We investigated the chemical bonding changes as a function of depth through the dielectric stack by taking a series of synchrotron photoemission spectra as we etched through the HfO{sub 2} film using a dilute HF-solution. We found that a very non-stoichiometric GeO{sub x} layer exists at the HfO{sub 2}/Ge interface. The valence band spectra near the Fermi level in each different film structure were carefully analyzed, and as a result, the valence band offset between Ge and GeO{sub x} was determined to be {Delta}E{sub v} (Ge-GeO{sub x}) = 2.2 {+-} 0.15 eV, and that between Ge and HfO{sub 2}, {Delta}E{sub v} (Ge-HfO{sub 2}) = 2.7 {+-} 0.15 eV.