Si self-diffusivity using isotopically pure 30 Si epitaxial layers

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2004-12, Vol.114-115, p.330-333
• Main Authors: Aid, S R, Sakaguchi, T, Toyonaga, K, Nakabayashi, Y, Matumoto, S, Sakuraba, M, Shimamune, Y, Hashiba, Y, Murota, J, Wada, K, Abe, T
• Format: Article
• Language: English
• ISSN: 0921-5107
• DOI: 10.1016/j.mseb.2004.07.055

In order to understand the properties of point defects in Si, it is important to clarify temperature dependence of Si intrinsic self-diffusion coefficient over a wide temperature range. In this work, we used highly isotopically enriched 30Si epi-layers as a diffusion source to bulk and epilayers Si and evaluated self-diffusion 30Si epi-layers were grown on each CZ-Si substrate and non-doped epi-layer grown on CZ-Si substrate using low pressure CVD with 30SiH4. Diffusion was performed in resistance furnaces under pure Ar (99.9%) atmosphere at temperature between 867 and 1300 deg C. After annealing, the concentrations of the respective Si isotopes were measured with SIMS. Diffusion coefficients of 30Si (called Si self-diffusivity, DSD) were determined using numerical fitting process with 30Si SIMS profiles. We found no major differences in self-diffusivity between in bulk Si and epi-layers Si. It was shown that within 867-1300 deg C range, DSD can be described by an Arrhenius equation with one single activation enthalpy, DSD = 14 exp (-4.37 eV/kT). The present result is in good agreement with that of Bracht et al.