This paper reports a real-life manufacturing case study in the short term p
roduction planning and control for a very large scale integrated (VLSI) cir
cuit manufacturing production unit
Dispatching in VLSI manufacturing is a crucial issue, since often binding c
onstraints are set on the delivery dates by the customers downstream in the
supply chain, while manufacturers, due to the huge fixed cost of capital g
oods, must ensure the full utilization of their shop floors. The complexity
of the manufacturing technology and the re-entrant nature of the resulting
production flows further add difficulties to the problem.
Starting from a shop floor scheduling based on simple dispatching rules, e.
g. FIFO rule, or the well-known 'minimum set-up' criterion, workcentres hav
e been firstly grouped according to their nature, then they have been class
ified according to their criticality in terms of production capacity and fl
exibility. Finally, for each class, a customized, yet suitable to be implem
ented, dispatching rule is proposed and tested through a wide simulation ca
mpaign. Experimental results show that the proposed dispatching approach le
ads to a superior overall output and, at the same time, to an increased del
ivery timeliness.