OEE

Overall Equipment Effectiveness (OEE) is a measure comparing how well manufacturing equipment is running compared to the ideal plant. The resulting measurement is expressed as the ratio of the actual output of the equipment divided by the maximum possible output of the equipment under ideal conditions. OEE is calculated by multiplying three independently measured values: Availability, Performance Rate, and Quality Rate. In other words, OEE takes an holistic view of all losses that impact on equipment performance: not being available when needed; not running at the ideal rate and not producing first pass A1 quality output. Typical losses include: Availability Planned downtimeSet up timeUnplanned recorded downtime or breakdowns Performance Rate Reduced speedMinor unrecorded stoppages Quality Rate RejectsReworkYield and Start up losses
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Overall Equipment Effectiveness - the actual output of a tool divided by the potential output of a tool assuming 100% utilization and 100% uptime. A measure of equipment effectiveness developed by SEMATECH.