The sites, gap levels, and migration barriers of interstitial H in Si are predicted. The hydrogenation of C-rich Si results in the formation of H 2*(C) and C 2H 2, in contrast to FZ-Si where H 2 molecules dominate. The fully saturated vacancy (VH 4) also forms. This complex is normally stable up to 650 °C. However, in C-rich Si, VH 4 anneals around 550 °C while the VH 3HC complex appears. There, C replaces one of the four Si nearest-neighbors to the vacancy. This implies that VH 4 begins to diffuse at 550 °C, and then traps at C s. This in turn implies that all the VH n complexes (n = 1, 2, 3, 4) are mobile at moderate temperatures. In this paper, we discuss the energetics of H in Si, summarize the key experimental and theoretical results about H interactions in C-rich Si, and discuss the migration paths and activation energies of the four VH n complexes.
|Number of pages||8|
|Journal||Physica Status Solidi (A) Applications and Materials Science|
|State||Published - Oct 2012|
- C-H complexes
- vacancy-hydrogen complexes