A hierarchical scheduling system using new weight assigned function in VLSI development lines

Many kinds of scheduling systems have been devised in order to realize an efficient operation of production lines by means of, for example, shortening turn around time (TAT). The VLSI development line requires the following special key items: (1) an efficient lot processing schedule as the number of process steps in given period are maximized; (2) the quick making of a schedule counteracting the alternation of recipes and changes of the period demanded for the experimentation. We developed a new hierarchical scheduling system (DYSCHE II: DYnamic SCHEduling system II) using a Weight Assigned Function (WAF) to overcome the problem of conventional scheduling systems.