Continuous and independent monitor wafer reduction in DRAM fab

DRAM short product life cycle and intense cost reduction battle in the market require monitor wafer effective reduction in manufacturing. Actions for monitor wafer reduction are as follows: we increased the ratio of the usage of vendor reclaimed wafers. For more reduction, we organized two teams to monitor wafer reduction in the manufacturing group and to extend monitor wafer in-house recycling and standardized simple way of measurement reduction. As a result of these activities, the ratio of monitor wafer to wafer start decreased from 1.5 (1993) to 0.5 (1999)