Uptime Sustainability Indices

1. Purpose - Actual Average Uptime of the critical tools/bottleneck (util% >; 80%) of fab in 2011 is at 83% whereas the actual target is at 86% (General Uptime for Process Tool in a mature fab is >;/= 85%) - Eg. Producer is the fab bottleneck (critical tool) for Q1'11 due to actual uptime not meeting target and wide variance in uptime performance (refer to Figure 1) - Need a tracking system/methodology to review and improve the critical/bottleneck tool uptime to ensure tool stability will not cause WIP to be built up in various tool station along the production line - To create awareness and provide overview of fab uptime performance. 2. Chosen Approach - 3 criteria were derived to scoop out problem tool set (refer to Figure 2) Criteria a) Tools that are critical with limited recover capacity i.e util% >; 80% Criteria b) Delta <; 0% → Actual 12 weeks Average - Target uptime/target Uptime Criteria c) OOC count >; 3 over 12 weeks period→ Actual Weekly Uptime <; (Target uptime-2%) - Analysis and Improvement Plan Breakdown of the downtime element into pareto chart to tackle the major contribution factor to poor uptime performance. With that we can find out root cause and derived Improvement Plan with timeline and ensure all actions item are in placed before the next tracking starts. Tools with ECD later than end of phase will be automatically included into the next phase. 3. Achieved Results - Before → Initial Phase of tracking in Q1'11 → Delta and OOC performance by module (refer to Figure 3) · All delta by module for most of the weeks are <; 0% · Module Average OOC performance at 5.8 (OOC Target is 3) - After · Tracking in Q1'1 2 → Delta and OOC performance by module (refer to Figure4) · All average delta by module for most of the weeks are >; 0% · Module Average OOC performance at 1.3 (OOC Target is 3) - The uptime has been back on tracked after we had a few rounds of scanning from Mar'12 till now - Meeting critical tools average target uptime of 86% - Fab move also has hit new high water mark after the uptime sustainability issues for critical tools are resolved.