300 mm tool automation and its impact on fab design and OEE

The challenge to building fabs in the 300 mm era will be to maximize the productivity of capital. One road in this direction is to increase Overall Equipment Effectiveness (OEE). At this time the approach being taken to increasing OEE involves the redesign of tools to improve reliability, increase throughput, reduce footprint, etc. The onset of 300 mm, however, presents an opportunity to take a more system wide approach at increasing OEE. In this paper we quantify the effects that material handling has on the cost of front end wafer fab by analyzing the effects that selection of batch size, carrier design, tool layout, wafer handling systems, etc. have on the Manufacturing Lead Time (MLT) of a chip. The paper then identifies design options for 300 mm handling components which increase the amount of time wafers spend getting value added in process tools, and decrease the overall non-value added handling times. This presents the basis for a description of a 300 mm fab tools and carriers which are designed as a total system to increase the OEE of the total fab, or the Overall Fab Effectiveness (OFE).