Transportation system

Abstract

An exemplary embodiment a substrate transport system is provided. The system has a guideway and at least one transport vehicle. The transport vehicle is adapted for holding at least one substrate and capable of being supported from and moving along the guideway. The guideway comprises at least one travel lane for the vehicle and at least one access lane offset from the travel lane allowing the vehicle selectable access on and off the travel lane.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) [0001] This application claims the benefit of U.S. Provisional Application No. 60 / 604,406 filed Aug. 24, 2004 which is incorporated by reference herein in its entirety.BACKGROUND [0002] 1. Field [0003] A system and method are disclosed for transporting reduced-capacity wafer carriers within a semiconductor fabrication facility. [0004] 2. Brief Description of Related Developments [0005] There is a desire in the semiconductor industry to reduce wafer cycle time through the fab and reduce the amount of work in progress as well as to improve wafer safety. Studies have shown that by moving to a single wafer carrier, wafer cycle time and WIP (wafers in process) is significantly reduced. In addition for the next generation wafer size (450 mm) the ITRS roadmap calls for single substrate carriers. Benefits of using single wafer or reduced capacity carriers include WIP reduction, process changeover time reduction and product ramp time improvement. Pro...

AI Technical Summary

Problems solved by technology

Problems arise where conventional single substrate carriers are employed relative to the ability of both the process tool and material transport system to effectively maintain the higher pace of the factory due to the larger number of carrier transport moves as compared to 13 or 25 wafer carriers.

Many such tools do not have the ability to fast swap, as in the case of a conventional single blade three axis robot.

Many such material transport systems do not have the ability to supply carriers at a high rate or with the capability to fast swap, as in the case of a conventional (overhead transport) OHT based material transport systems as implemented in conventional 300 mm fabs.

Conventional material transport systems are highly rigid in the transport or movement scheme of the carriers transported thereby, and do not offer sufficient transport flexibility desired with carriers having reduced workpiece capacity (e.g. less than conventional 13 or 25 workpiece pods).

Nevertheless, the high speed pathways do not enable transport on a service pathway to pass stopped or slowed transport on the service pathway.

As may be realized, the rigidity of the transport scheme of conventional material transport systems impairs the ability in directing workpieces to the full advantage of FAB tool availability with a commensurate degradation in the achievable FAB throughput.

Images