Online Rescheduling in Semiconductor Manufacturing

Semiconductor manufacturing rescheduling problems are difficult to solve in real time due to numerous disturbances. We focus on maintaining the existing schedule and propose online semiconductor manufacturing rescheduling. To handle temporary disturbances and obtain a new feasible schedule, our proposal revises the given schedule based on affected operation rescheduling with operation sorting (sorting-AOR) based on schedule stability. To reduce deadline violations, we propose improving schedules two or more days ahead based on a fast local search algorithm for semicritical paths. In problems with 200,000 processes, this handles disturbances and gets new feasible schedules and better revised schedules in less than 1 minute. This is more effective than conventional dispatching-rule-based approaches, some of which have been applied in different facilities because it provides higher schedule stability and fewer deadline violations.