Simulations and Experiments on Activation of Doped Silicon Wafers Based on Dual Beam of 785 nm Semiconductor Laser and 10.6 μm CO2 Laser

In this study, we analyzed the spatiotemporal distribution of annealing temperature using a dual-beam dynamic scanning annealing technique based on a CO2 laser (10.6 μm) and a 785 nm laser, and the effects of laser energy density, scanning speed, and preheating temperature on the resulting temperature. We systematically examined the influence of key process parameters, including laser energy density, scanning speed, and preheating temperature, on the annealing temperature. Our aim was to optimize annealing conditions to enhance the electrical properties of the materials, as indicated by reduced sheet resistance, controlled diffusion depth of doped ions, and higher activation rates. This approach ensured high activation rates of doped ions while limiting dopant re-diffusion to merely 3.6 nm in the depth direction, as confirmed by concentration profile analysis. Furthermore, based on temperature distribution, deformation of the wafer surface was analyzed. The results indicate that under the employed process parameters, no significant adverse effects on wafer flatness or structural integrity were observed.