First principles studies of relativistic and spin–orbit effects on the HfO2 band structures

Electronic band and structural properties of the cubic, tetragonal, and monoclinic phases of HfO2 are calculated. The all electron ab initio self-consistent linear augmented plane-wave method within the framework of the local-density approximation was used, and full-relativistic contributions were taken into account. For the cubic phase, the lattice constant was obtained through a total energy minimization. For the tetragonal phase, the lattice parameters were calculated from the equilibrium volume obtained by variation of the ratio c/a, besides the relaxation of internal parameters (atomic positions). The monoclinic phase was studied using parameters as extracted from previous theoretical calculations. The electronic band structures for the three different structural phases present the same chemical trends relative to energy band gaps and valence-band states. The relativistic and spin–orbit effects are more pronounced for deep valence states. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

[1]  G. A. Farias,et al.  Full-relativistic calculations of the SrTiO3 carrier effective masses and complex dielectric function , 2003 .

[2]  John Robertson,et al.  Band offsets and Schottky barrier heights of high dielectric constant oxides , 2002 .

[3]  V. Fiorentini,et al.  Theoretical evaluation of zirconia and hafnia as gate oxides for si microelectronics. , 2002, Physical review letters.

[4]  Andre Stesmans,et al.  Internal photoemission of electrons and holes from (100)Si into HfO2 , 2002 .

[5]  T. Jackson,et al.  Dielectric functions and optical bandgaps of high-K dielectrics for metal-oxide-semiconductor field-effect transistors by far ultraviolet spectroscopic ellipsometry , 2002 .

[6]  D. Vanderbilt,et al.  First-principles study of structural, vibrational, and lattice dielectric properties of hafnium oxide , 2002, cond-mat/0202454.

[7]  A. Demkov.  Investigating Alternative Gate Dielectrics: A Theoretical Approach , 2001 .

[8]  J. K. Dewhurst,et al.  Relative stability of ZrO 2 and HfO 2 structural phases , 1999 .

[9]  R. D. Groot,et al.  The conduction bands of MgO, MgS and HfO2 , 1998 .

[10]  Burke,et al.  Generalized Gradient Approximation Made Simple. , 1996, Physical review letters.

[11]  John Wang,et al.  Hafnia and hafnia-toughened ceramics , 1992, Journal of Materials Science.

[12]  Peter Blaha,et al.  Full-potential, linearized augmented plane wave programs for crystalline systems , 1990 .

[13]  Michael M. Schieber,et al.  Chemical vapor deposition and characterization of HfO2 films from organo-hafnium compounds , 1977 .