Publications

Reaction of BCl3 with H- and Cl-terminated Si(1 0 0) as a pathway for selective, monolayer doping through wet chemistry

Silva-Quinones, Dhamelyz; He, Chuan; Butera, Robert E.; Wang, George T.; Teplyakov, Andrew V.

The reaction of boron trichloride with the H- and Cl-terminated Si(1 0 0) surfaces was investigated to understand the interaction of this molecule with the surface for designing wet chemistry-based silicon surface doping processes using a carbon- and oxygen-free precursor. The process was followed with X-ray photoelectron spectroscopy (XPS). Within the reaction conditions investigated, the reaction is highly effective on Cl-Si(1 0 0) for temperatures below 70 °C, at which point both surfaces react with BCl3. The XPS investigation followed the formation of a B 1s peak at 193.5 eV corresponding to (B-O)x species. Even the briefest exposure to ambient conditions lead to hydroxylation of surface borochloride species. However, the Si 2p signature at 102 eV allowed for a confirmation of the formation of a direct Si-B bond. Density functional theory was utilized to supplement the analysis and identify possible major surface species resulting from these reactions. This work provides a new pathway to obtain a functionalized silicon surface with a direct Si-B bond that can potentially be exploited as a means of selective, ultra-shallow, and supersaturated doping.