We investigated the number of Ce4+ ions required to produce one Br-ion in the oxidation of bromomalonic acid by Ce4+ under conditions appropriate tg the oscillating Belousov-Zhabotinskii (BZ) reaction. We found a ratio of 1 : 1, in agreement with earlier results by Jwo and Noyes (J. Am. Chem. SOC. 1975, 97, 5422), in the presence of oxygen. With oxygen excluded from the system, we found a ratio of 2:l. The presence of malonic acid in the system had no effect on the bromide production, contrary to the assumption of recent theoretical models of the Belousov-Zhabotinskii reaction.

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Strained Si-based technology has imposed a new challenge for understanding dopant implantation and diffusion in SiGe that is often used as the buffer layer for a strained Si cap layer. In this work, we describe our latest modeling effort investigating the difference in dopant implantation and diffusion between Si and SiGe. A lattice expansion theory was developed to account for the volume change due to Ge in Si and its effect on defect formation enthalpy. The theory predicts that As diffusion in SiGe is enhanced by a factor of ~10, P diffusion by a factor of ~2, and B diffusion is retarded by a factor of ~6, when compared to bulk Si. These predictions are consistent with experiment. Dopant profiles for As, P, and B were simulated using process simulators FLOOPS and DIOS. The simulated profiles are in good agreement with experiment. Dopant implantation was simulated using REED-MD. The results showed a noticeable difference in peak and tail positions SiGe compared to Si.

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