Quantifying capacity loss associated with staffing in a semiconductor manufacturing line

Even on a base of total time, staffing related capacity loss is one of the major contributors to underperforming tools. The loss of capacity caused by staffing, whether planned or unplanned, has the potential of being the single most significant operational detractor in a semiconductor line. A number of issues related to staffing strategies and operational methodologies for a semiconductor line affect capacity loss. On the one hand, there is the need to be cost competitive by reducing staffing and increasing productivity. On the other, the cost of idle equipment and loss of tool capacity due to insufficient staffing must be considered. Many issues are involved in determining accurate capacity loss because of staffing and identifying the components of that loss. This paper discusses ways to determine capacity loss and other concerns related to staffing on various tool sets in a semiconductor manufacturing line using the techniques of multiobservation study (MOS) and data analysis. Additionally, it describes the link between the quantity and main contributing factors that result in a given loss. Finally, it examines some strategies for reducing the effect of staffing on capacity.