Tight binding modeling of heterojunction band offsets as a function of pressure and composition


Unlu H.

PHYSICA STATUS SOLIDI B-BASIC RESEARCH, cilt.223, sa.1, ss.195-204, 2001 (SCI İndekslerine Giren Dergi) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 223 Konu: 1
  • Basım Tarihi: 2001
  • Dergi Adı: PHYSICA STATUS SOLIDI B-BASIC RESEARCH
  • Sayfa Sayıları: ss.195-204

Özet

We present a new tight binding view of the heterojunction band offsets. The model considers the nonorthogonality of the sp(3) set of orbitals of adjacent atoms and spin-orbit coupling and uses the Hartre-Fock atomic energies and interacting matrix clement, obtained by fitting bulk band structures of semiconductors, to determine the valence band energies at 0 K and 1 bar. The valence band offsets are then obtained by aligning the temperature, pressure, and composition dependent vacuum levels, screened by the optical dielectric constants of bulk materials for thermodynamic equilibrium across heterointerfaces. Excellent agreement between the model predictions and experiment fur the valence band offsets suggests that the bulk band structure properties play a significant rule in determining the band offsets for lattice matched heterojunctions and Schottky barriers.