Calculation of solid-phase reaction rates induced by a scanning cw laser

Abstract

An analytical model is presented for solid-phase reactions induced by a scanning cw laser. The results are applicable for both rate-limited reactions, such as the regrowth of implanted amorphous Si, and diffusion-limited reactions, such as the formation of metal silicides. The effect of the laser is interpreted in terms of a furnace anneal at an ’’effective temperature,’’ Teff, for an ’’effective time,’’ teff. Teff is shown to be equal to the maximum laser-induced surface temperature, while teff equals the laser dwell time multiplied by a ’’dwell-time reduction factor’’ which is a rational function of several material and annealing parameters and is typically on the order of (1)/(3) . A comparison of theory and experiment is made for the specific case of the formation of Pd2Si.