Optimal design and operation of a spatially distributed multiscale process, with regard to layered heterostructure growth

Determining the optimal operation of processes modeled by multiscale systems presents many challenges, because of complexities in modeling and the extensive computational requirements needed to solve them. Application to layered heterostructure deposition is considered here, where an additional challenge of interface characterization is encountered. A solution methodology is applied to the fabrication of a device consisting of alternating layers of gallium arsenide and aluminum arsenide, with the intent of minimizing thickness nonuniformity and interfacial step density. Using a finite-element solver and kinetic Monte Carlo simulations, we were able to balance reductions in thickness nonuniformity and interfacial step density with maintaining favorable operating conditions in a computationally efficient manner.