Abstract
The thermal stability of amorphous Zr:Al mixed oxide films of different composition, produced on (001) silicon wafers by the atomic layer deposition method is studied by transmission electron microscopy during in situ heating experiments. The temperatures at which phase separation and crystallization occur are composition dependent. The crystallization of thick films (55–70 nm), deposited on HF-treated silicon surfaces covered with a 15 cycles Al2O3 layer, results in the formation of cubic ZrO2 and cubic γ–Al2O3. In very thin films (5 nm), deposited on silicon surfaces covered with a 0.5 nm SiO2 thin film, the formation of tetragonal zirconium disilicide (ZrSi2) is observed in the microscope vacuum, at temperatures above 900 °C. This effect depends on the thickness of the as deposited thin film.
Similar content being viewed by others
References
G.D. Wilk, R.M. Wallace, and J.M. Anthony: High-k gate dielectrics: Current status and materials properties considerations. J. Appl. Phys. 89, 5243 (2001).
K.J. Hubbard and D.G. Schlom: Thermodynamic stability of binary oxides in contact with silicon. J. Mater. Res. 11, 2757 (1996).
M-Y. Ho, H. Gong, G.D. Wilk, B.W. Busch, M.L. Green, W.H. Lin, A. See, S.K. Lahri, M.E. Loomans, P.I. Raisanen, and T. Gustafsson: Suppressed crystallization of Hf-based dielectrics by controlled addition of Al2O3 using atomic layer deposition. Appl. Phys. Lett. 81, 4218 (2002).
R.B. van Dover, M.L. Green, L. Manchanda, L.F. Schneemeyer, and T. Siegrist: Composition-dependent crystallization of alternative gate dielectrics. Appl. Phys. Lett. 83, 1459 (2003).
H. Kim, P.C. McIntyre, and K.C. Saraswat: Effects of crystallization on the electrical properties of ultrathin HfO2 dielectrics grown by atomic layer deposition. Appl. Phys. Lett. 82, 106 (2003).
H. Kim, A. Marshall, P.C. McIntyre, and K.C. Saraswat: Crystallization kinetics and microstructure-dependent leakage current behavior of ultrathin HfO2 dielectrics: In situ annealing studies. Appl. Phys. Lett. 84, 2064 (2004).
S.V. Ushakov, A. Navrotsky, Y. Yang, S. Stemmer, K. Kukli, M. Ritala, M.A. Leskala, P. Fejes, A. Demkov, C. Wang, B.-Y. Nguyen, D. Triyoso, and P. Tobin: Crystallization in hafniaand zirconia-based systems. Phys. Status Solidi B 241, 2268 (2004).
C. Zhao, O. Richard, E. Young, H. Bender, G. Roebben, S. Haukka, S. De Gendt, M. Houssa, R. Carter, W. Tsai, O. Van Der Biest, and M. Heyns: Thermostability of amorphous zirconium aluminate high-k layers. J. Non Cryst. Solids 303, 144 (2002).
K. Kukli, K. Forsgren, J. Aarik, T. Uustare, A. Aidla, A. Niskaen, M. Ritala, M. Leskela, and A. Harsta: Atomic layer deposition of zirconium oxide from zirconium tetraiodite, water and hydrogen peroxide. J. Cryst. Growth 231, 262 (2001).
E.B.O. da Rosa, J. Morais, R.P. Pezzi, L. Miotti, and I.J.R. Baumvol: Annealing of ZrAlxOy ultra thin films on Si in a vacuum or in O2. J. Electrochem. Soc. 148, G695 (2001).
C. Zhao, O. Richard, H. Bender, M. Caymax, S. De Gendt, M. Heyns, E. Young, G. Roebben, O. Van Der Biest, and S. Haukka: Miscibility of amorphous ZrO2–Al2O3 binary alloys. Appl. Phys. Lett. 80, 2374 (2002).
P.J. Chen, E. Cartier, R.J. Carter, T. Kauerauf, C. Zhao, J. Petry, V. Cosnier, Z. Xu, A. Kerber, W. Tsai, E. Young, S. Kubicek, M. Caymax, W. Vandervorst, S. De Gendt, M. Heyns, M. Copel, W.F.A. Besling, P. Bajolet, and J. Maes: The thermal stability of Zr-aluminate-based high-k gate stacks, in VLSI Technology Digest of Technical Papers 2002 Symposium (IEEE), Honolulu, Pull, Wilderhehr and Gaithersburg, MD 20877, USA, pp. 192–193.
J. Pétry, O. Richard, W. Vandervorst, T. Conard, J. Chen, and V. Cosnier: Effect of N2 annealing on AlZrO oxide. J. Vac. Sci. Technol. A 21, 1482 (2003).
R.B. van Dover, D.V. Lang, M.L. Green, and L. Manchanda: Crystallization kinetics in amorphous (Zr0.62Al0.38)O1.8 thin films. J. Vac. Sci. Technol. A 19, 2779 (2001).
C. Ghica, L. Nistor, H. Bender, A. Steegen, A. Lauwers, K. Maex, and J. Van Landuyt: In situ TEM study of the silicidation process in Co thin films on patterned (001) Si substrates. J. Mater. Res. 16, 701 (2001).
V. Teodorescu, L. Nistor, H. Bender, A. Steegen, A. Lauwers, K. Maex, and J. Van Landuyt: In situ transmission-electronmicroscopy study of Ni silicide phases formed on (001) Si active lines. J. Appl. Phys. 90, 167 (2001).
R.L. Puurunen, W. Vandervorst, W. Besling, O. Richard, H. Bender, T. Conard, C. Zhao, A. Delabie, M. Caymax, S. Degendt, M. Heyns, M.M. Viitanen, M. de Ridder, H.H. Brongersma, Y. Tamminga, T. Dao, T. de Win, M. Verheijen, M. Kaiser, and M. Tuominen: Island growth in the atomic layer deposition of zirconium oxide and aluminum oxide on hydrogenterminated silicon: growth mode modelling and transmission electron microscopy. J. Appl. Phys. 96, 4878 (2004).
ASTM-File No. 27-977.
ASTM-File No. 10-427.
ASTM-File No. 10-236.
O. Richard, H. Bender, M. Houssa, and C. Zhao: Characterization of ALCVD ZrO2 thin films by TEM. Inst. Phys. Conf. Ser. 169, 407 (2001).
V. Afanas’ev, A. Stesmans, B.J. Mrstik, and C. Zhao: Impact of annealing-induced compaction on electronic properties of atomiclayer- deposited Al2O3. Appl. Phys. Lett. 81, 1678 (2002).
L. Nistor, O. Richard, C. Zhao, H. Bender, A. Stesmans, and G. Van Tendeloo: A microstructural study of the thermal stability of atomic layer deposited Al2O3 thin films. Inst. Phys. Conf. Ser. 180, 397 (2003).
M. Copel, M. Gribelyuk, and E. Gusev: Structure and stability of ultrathin zirconium oxide layers on Si (001). Appl. Phys. Lett. 76, 436 (2000).
T.S. Jeon, J.M. White, and D.L. Kwong: Thermal stability of ultrathin ZrO2 films prepared by chemical vapour deposition on Si (100). Appl. Phys. Lett. 78, 368 (2001).
R. Tromp, G.W. Rubloff, P. Balk, F.K. Le Goues, and E.J. van Loenen: High-temperature SiO2 decomposition at the SiO2/Si interface. Phys. Rev. Lett. 55, 2332 (1985).
N. Miyata, H. Watanabe, and M. Ichikawa: Thermal decomposition of ultrathin Si oxide layer around a Si (001)–(2x1) window. Phys. Rev. Lett. 84, 1043 (2000).
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, 792 (2004).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Nistor, L.C., Richard, O., Zhao, C. et al. Thermal stability of atomic layer deposited Zr:Al mixed oxide thin films: An in situ transmission electron microscopy study. Journal of Materials Research 20, 1741–1750 (2005). https://doi.org/10.1557/JMR.2005.0217
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1557/JMR.2005.0217