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Film and Interface Layer Compositionof Rare Earth (Lu, Yb) Oxides Depositedby ALD

Chapter
Part of the Topics in Applied Physics book series (TAP, volume 106)

Abstract

Thin Lu2O3, Yb2O3, and Lu silicate layers were grown on Si using Atomic Layer Deposition (ALD), and studied mainly with X-ray photoelectron spectroscopy (XPS) and low-energy ion spectroscopy (LEIS). Experimental results on elemental composition and chemical state both in thin oxide layers and at the interface with the Si substrate, and their evolution upon different heat treatments, are presented. Besides oxygen states attributed to stoichiometric RE2O3 (RE=Lu, Yb) and OH, an additional, loosely bound state is identified in a subsurface layer at equilibrium conditions for both Lu2O3 and Yb2O3 layers. A variety of thin (amorphous) Lu silicate films grown by ALD with different compositions depending on the precursor and/or growth conditions was unambiguously established by XPS, the components’ chemical shifts found to be a monotonous function of the composition. As grown continuous ultrathin (≤ 5nm) Lu and Yb oxide films on Si appear to consist of a hydroxide on top and of a silicate layer, ~ 1–3 nm in thickness, at the interface with the Si substrate, the stack is converted into amorphous silicates upon post-deposition annealing in N2 and appears further stable on Si at least up to annealing at T=1100∘C (in N2).

Keywords

71.55.-i; 72.80.Sk; 73.20.At; 75.47.Lx; 77.55.+f 

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References

  1. G. D. Wilk, R. M. Wallace, J. M. Anthony: High-κgate dielectrics: Current status and materials properties, J. Appl. Phys. 89, 5243 (2001) CrossRefGoogle Scholar
  2. D. G. Schlom, J. H. Haeni: A thermodynamic approach to selecting alternative gate dielectrics, MRS Bull. 27, 198 (2002) Google Scholar
  3. A. V. Prokofiev, A. I. Shelyakh, B. T. Melekh: Periodicity in the band gap variation of 2X3 (= , , ) in the lanthanide series, J. All. Comp. 242, 41 (1996) CrossRefGoogle Scholar
  4. J. Robertson: Band offsets of wide-band-gap oxides and implications for future electronic devices, J. Vac. Sci. Technol. B 18, 1785 (2000) CrossRefGoogle Scholar
  5. G. Lucovsky, Y. Zhang, G. B. Rayner, G. Appel, H. Ade, J. L. Whitten: Electronic structure of high-transition metal oxides and their silicate and aluminate alloys, J. Vac. Sci. Technol. B 20, 1739 (2002) CrossRefGoogle Scholar
  6. G. Scarel, E. Bonera, C. Wiemer, G. Tallarida, S. Spiga, M. Fanciulli, I. L. Fedushkin, H. Schumann, Y. Lebedinskii, A. Zenkevich: Atomic layer deposition of 2O3, Appl. Phys. Lett. 85, 630 (2004) CrossRefGoogle Scholar
  7. S. Ohmi, M. Takeda, H. Ishiwara, H. Iwai: Electrical characteristics for 2O3 thin films fabricated by e-beam deposition method, J. Electrochem. Soc. 151, G279 (2004) CrossRefGoogle Scholar
  8. Y. Lebedinskii, A. Zenkevich: Silicide formation at 2/and 2/interfaces induced by + ion bombardment, J. Vac. Sci. Technol. A 22, 2261 (2004) CrossRefGoogle Scholar
  9. H. Schumann, I. L. Fedushkin, M. Hummert, G. Scarel, E. Bonera, M. Fanciulli: Crystal and molecular structure of [(η^55H4SiMe3)2LuCl]2 – suitable precursor for 2O3 films, Z. Naturforsch. 59b, 1035 (2004) Google Scholar
  10. J. P. Espinos, A. R. Gonzalez-Elipe, J. A. Odriozola: XPS study of lutetium oxide samples with different hydration / carbonation degrees as a function of the preparation method, Appl. Surf. Sci. 29, 40 (1987) CrossRefGoogle Scholar
  11. S. Elliott, G. Scarel, C. Wiemer, M. Fanciulli, Y. Lebedinskii, A. Zenkevich, I. L. Fedushkin: Precursor combinations for ALD of rare earth oxides and silicates – A quantum chemical and x-ray study, Electrochem. Soc. Proc. 2005-09, 605 (2005) Google Scholar
  12. S. Stemmer: Thermodynamic considerations in the stability of binary oxides for alternative gate dielectrics in complementary metal-oxide-semiconductors, J. Vac. Sci. Technol. B 22, 791 (2004) CrossRefGoogle Scholar
  13. R. L. Puurunen, W. Vandervorst: Island growth as a growth mode in atomic layer deposition: A phenomenological model, J. Appl. Phys. 96, 7686 (2004) CrossRefGoogle Scholar
  14. S. Spiga, C. Wiemer, G. Tallarida, G. Scarel, S. Ferrari, G. Seguini, M. Fanciulli: Effects of the oxygen precursors on the electrical and structural properties of 2 films grown by atomic layer deposition on , Appl. Phys. Lett. 87, 112904 (2005) CrossRefGoogle Scholar
  15. L. Marsella, V. Fiorentini: Structure and stability of rare-earth and transition-metal oxides, Phys. Rev. B 69, 172103 (2004) CrossRefGoogle Scholar

Authors and Affiliations

  1. 1.Department 25 (Solid State Engineering)Moscow Engineering Physics InstituteMoscowRussian Federation
  2. 2.National Laboratory MDM-INFM-CNRCNR-INFM MDMAgrate Brianza (MI)Italy

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