Optimal control of transient enhanced diffusion

Transient enhanced diffusion of boron inhibits the formation of ultrashallow junctions needed in the next-generation of microelectronic devices. Reducing the junction depth using rapid thermal annealing with high heating rates comes at a cost of increasing sheet resistance. The focus of this study is to design the optimal annealing temperature program that gives the minimum junction depth while maintaining satisfactory sheet resistance. Comparison of different parameterizations of the optimal trajectories shows that linear profiles gave the best combination of minimizing junction depth and sheet resistance. Worst-case robustness analysis of the optimal control trajectory motivates improvements in feedback control implementations for these processes.