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Figure 1.
The flow above shows the complexity of the overall fabrication process and
provides an overview of necessary data capture components.
Data for logistics, inline metrology and test are captured at multiple points
of the fabrication process.
The complex fabrication process requires accurate disposition of data which is
required for foundry partners to understand and react to design issues.
In the foundry business model, which this proposal specifically addresses, fabless
semiconductor companies (FSC) rely on the manufacturing fabs to transmit
in line test, wafer test and module test data to the FSC for subsequent use by the
FSC engineering teams.
The data is stored by the FSC in their own databases so that engineers may
perform advanced statistical analysis as required by business needs.
Increasingly FCS are using this data to compare yields and processes for like
products manufactured by different foundry partners.
At present there are no industry wide standards as to how this data
is formatted for transmission to customers or business partners.
Key Points
Data is sent from foundry to the FSC (or business
partner).
Data is sent on a lot by lot basis.
One lot being a fixed number of semiconductor wafers (usually 25) that is
processed as a unit.
Data is sent as soon as it can be reconciled with logistics and the
data integrity is verified.
The frequency of the transfer of information is dependant on the
number of lots the FCS has ordered from the foundry and the manufacturing schedule.
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