A job-priority based soft scheduling approach for uncertain work area scheduling in Semiconductor Manufacturing
针对半导体制造中氧化/沉积/扩散工作区的不确定调度问题，提出一种基于作业优先级的软调度方法，通过离线优化与在线调度结合，适应生产环境波动。
This paper studies the uncertain scheduling problem of the oxidation/deposition/diffusion work area in semiconductor manufacturing, where fluctuations in arrival times and processing times are considered. To overcome the shortcomings of the conventional schedule, which has a fixed processing machine and starting time for each operation, we design a new form of schedule called the job-priority based soft schedule. Its basic idea is to assign global priority to each job in advance, and to make remaining decisions (including batch formation, machine assignment and real-time dispatching) in the process of implementing the initial soft schedule. Then we develop a job-priority based soft scheduling approach that involves two layers: (1) in the offline optimisation layer, an initial soft schedule is obtained by a proposed hybrid harmony search algorithm; (2) in the online dispatching layer, the remaining decisions are made in real time by a designed online heuristic rule. The comparative experimental results demonstrate that the two-layer soft scheduling mechanism can effectively adapt to an uncertain production environment due to its integration of the global optimisation perspective and local flexibility.