Impact of qualification management on scheduling in semiconductor manufacturing

A qualification management software that proposes recipe qualifications on tools in toolsets for semiconductor manufacturing has been developed. The qualification proposals are based on flexibility measures that have been shown to model capacity allocation in semiconductor workshops. In this paper, qualifications are used in order to see how increased flexibility for the capacity allocation improve scheduling. For this a scheduler simulator for the photolithography area has been used. Tests prove that qualifications - if they are well managed - both enable the simulator to achieve better scheduling and enable toolsets to be less sensitive to tool breakdowns.