Contribution of Carbon to Growth of Boron-Containing Cluster in Heavily Boron-Doped Silicon

It is well known that substitutional carbon (C) atoms can capture excess self-interstitial silicon (Si) atoms and suppress the diffusion of ion-implanted interstitial-type dopants, such as boron (B), in Si In the case of B concentrations as high as similar to 1 x 10(21) cm(-3), the B activation ratio in Si decreases with C incorporation Thus, many studies on stable B-containing clusters and/or precipitates in heavily doped Si with a C additive have thus far been conducted However, the impact of the C incorporation on the activation and clustering of B atoms in Si is yet to be researched In this work, the chemical bonding features of B and C atoms in heavily B-doped Si with different C contents after high-temperature annealing were characterized systematically by high-resolution X-ray photoelectron spectroscopy (XPS) It was found that the C incorporation enhances B-clustering at B concentrations higher than similar to 1 x 10(21) cm(-3) after 1050 degrees C spike annealing In addition, the formation of C-B bonds with accompanying B-clustering was confirmed by photoemission measurement using a hard X-ray As a result, the intrinsic B-diffusion was observed to be markedly suppressed by the C incorporation under thermodynamic equilibrium annealing at 1000 degrees C (C) 2010 The Japan Society of Applied Physics