LCAO Recursion Approach for the Bound Electron States at the 90°‐Partial Dislocation in Silicon

Abstract

AbstractThe evaluation of bound electron states at extended lattice defects in Si is studied within an LCAO scheme under full inclusion of s‐, p‐, and d‐states and their mutual non‐orthogonality. The levels are determined from a continuous‐fraction recursion treatment. Application to a supercell model of the unreconstructed 90°‐partial dislocation demonstrates that the method works well for basis sets of 2560 complex basis functions. The present results for the bound electron states at the 90°‐partial dislocation in Si appreciably differ from the earlier tight binding estimates due to the here included dangling bond interactions. Two one‐dimensional bands of bound states are found showing large band splitting inside the Brillouin zone and degeneracy of the bands at the zone boundary with an occupation limit between empty and full states 0.12 eV above the valence band edge.