The key predictions of ab-initio Hartree-Fock (HF) calculations for copper in silicon clusters are reviewed. Preliminary results of ab-initio molecular-dynamics simulations in periodic supercells, based on density-functional (DF) theory with atomic-like basis sets are given. These calculations are performed in periodic supercells containing 64 or 128 host atoms and a varying number of k points. The electronic configuration of interstitial copper predicted by the DF calculations is very similar to the HF one. In a vacancy, copper forms four Cu-Si covalent bonds. In a divacancy, Cu moves along the <111> direction toward the center of the void and becomes 6-fold coordinated. The interactions between substitutional copper and interstitial hydrogen are obtained from dynamic and static runs. Hydrogen traps at Cus without forming Si-H bonds. Instead, copper becomes 5-,6-, then 7-fold coordinated as one, two, or three H interstitials bind to it.
|Number of pages||8|
|Journal||Solid State Phenomena|
|State||Published - 2002|
|Event||Gettering and Defect Engineering in Semiconductor Technology 2001 - S. Tecla, Italy|
Duration: Sep 30 2001 → Oct 3 2001
- Molecular dynamics