Single-wafer cluster tool performance: an analysis of throughput

Cluster tools gained greater acceptance over the past several years, although concerns still exist over the throughput these tools can achieve. This paper presents an analysis of the relationship between process times, transport times, and maximum throughput in an individual cluster tool. Theoretical models which quantify the time required to process both an individual wafer and a lot in a cluster tool are developed. Three techniques for increasing throughput, based on these models, are also presented. These modifications require minimal modification of many existing designs and can yield significant increases in performance