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Because the probing factory is due-date oriented while the
fabrication factory is throughput oriented in the production
planning, this thesis thus considers such a transition to do
the production plans. This proposed production planning model
takes the throughput schedule of the fabrication factory as
well as the characteristics of test machines in the probing
factories into consideration. It is designed to increase the
throughput of the probing factory under the constraint of the
due date satisfaction. Use the four-week planning results of
the detail production planning of the fabrication factory, the
proposed model is divided into three modules: production
control module, capacity planning module, and the feedback
module. The production control module takes the first week''s
result to schedule the test machines in the probing factory.
To satisfy the due-date requirement, each lot is graded to one
of the four levels according to its arrival time, its due date,
and the capacity availability of the required machine type.
Each level has different priority for releasing the lots to
shop-floor. However, all the lots of the same level are
considered simultaneously so as to reduce the set up time.
The capacity planning module takes the planning results of the
other three weeks to check whether the required probing
capacity can be fulfilled or not. The purpose of this module
is to avoid test machines having unbalanced capacity
allocation such that dates are missed. The information
obtained from the above two modules will be feedback to the
fabrication factory by the feedback module. The fabrication
factory thus can adjust its quantity and its throughput time
by detail schedule planning so as to improve the due date
performance. The results of the case studies show that the
production planning model indeed achieves the due date
performance and controls the setup time of test machines
simultaneously. The competitive advantages of the
semiconductor factory thus is enhanced.
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