Thermodynamic stability of high-K dielectric metal oxides ZrO2 and HfO2 in contact with Si and SiO2

We present theoretical and experimental results regarding the thermodynamic stability of the high-k dielectrics ZrO2 and HfO2 in contact with Si and SiO2. The HfO2/Si interface is found to be stable with respect to formation of silicides whereas the ZrO2/Si interface is not. The metal–oxide/SiO2 interface is marginally unstable with respect to formation of silicates. Cross-sectional transmission electron micrographs expose formation of nodules, identified as silicides, across the polycrystalline silicon/ZrO2/Si interfaces but not for the interfaces with HfO2. For both ZrO2 and HfO2, the x-ray photoemission spectra illustrate formation of silicate-like compounds in the MO2/SiO2 interface.

[1]  F. Albert Cotton,et al.  Advanced Inorganic Chemistry , 1999 .

[2]  D. Vanderbilt,et al.  Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. , 1990, Physical review. B, Condensed matter.

[3]  G. Kresse,et al.  Ab initio molecular dynamics for liquid metals. , 1993 .

[4]  O. J. Kleppa,et al.  Standard enthalpies of formation of some 3d transition metal silicides by high temperature direct synthesis calorimetry , 1998 .

[5]  K. Trueblood,et al.  The crystal structure of baddeleyite (monoclinic ZrO2) , 1959 .

[6]  Georg Kresse,et al.  Norm-conserving and ultrasoft pseudopotentials for first-row and transition elements , 1994 .

[7]  Evgeni P. Gusev,et al.  Structure and stability of ultrathin zirconium oxide layers on Si(001) , 2000 .

[8]  R. Wallace,et al.  High-κ gate dielectrics: Current status and materials properties considerations , 2001 .

[9]  Hafner,et al.  Ab initio molecular dynamics for open-shell transition metals. , 1993, Physical review. B, Condensed matter.

[10]  G. Kresse,et al.  Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set , 1996 .

[11]  M. W. Chase,et al.  NIST-JANAF Thermochemical Tables Fourth Edition , 1998 .

[12]  H. Monkhorst,et al.  SPECIAL POINTS FOR BRILLOUIN-ZONE INTEGRATIONS , 1976 .

[13]  G. V. Gibbs,et al.  The structure of zircon: A comparison with garnet , 1971 .

[14]  Pierre Villars,et al.  Pearson's handbook of crystallographic data for intermetallic phases , 1985 .

[15]  Jackson,et al.  Atoms, molecules, solids, and surfaces: Applications of the generalized gradient approximation for exchange and correlation. , 1992, Physical review. B, Condensed matter.

[16]  I. Barin.  Thermochemical data of pure substances , 1989 .

[17]  D. Schlom,et al.  Thermodynamic stability of binary oxides in contact With silicon , 1996 .