The Properties of Shuffle Screw Dislocations in Semiconductors Silicon and Germanium

The dislocation widths, Peierls barriers and Peierls stresses for shuffle screw dislocations in diamond structure crystals, Si and Ge, have been calculated by the improved P-N theory. The widths are about 0.6b, where b is the Burgers vector. The Peierls barrier for shuffle screw dislocation in Si and Ge, is about 3.61~4.61meV/Å and 5.31~13.32meV/Å, respectively. The Peierls stress is about 0.28~0.33GPa and 0.31~0.53GPa, respectively. The calculated Peierls barriers and stresses are likely the results of shuffle screw dislocation with metastable core which is centered on the bond between two atoms.