300 mm fab automation technology options and selection criteria

Fab automation is being widely applied in 200 mm fabs. With the advent of new carrier designs, and equipment standards being set for 300 mm tools, opportunities arise for new and more efficient methods to transport, store, and load 300 mm carriers. This can result in more expansive yet simplified uses of automation and in a large variety of options for factory layout and application of the automation systems. The challenge to building fabs in the 300 mm era will be to maximize the productivity of capital. There are a number of options available in doing so. Fabs can be designed to minimize footprint, equipment cost, cycle time, or to increase Overall Equipment Effectiveness (OEE). A combination of these may also be used. The onset of 300 mm production presents an opportunity to take a more system wide approach at increasing productivity than has been used before. In this paper we will quantify the effects that material handling has on the cost of front-end wafer fab by analyzing the effects that layout and automation techniques have on footprint, fab costs and the Manufacturing Lead Time (MLT) of a chip. The article then identifies some of design options for 300 mm automated fabs (least footprint, least cost, and lowest MLT) and illustrates their suitability to different operating needs. Readers will see how combinations of Monorails, Stockers and Automated Vehicles can be used to achieve different goals.