US Patent 6877944 Configuration for transporting a semiconductor wafer carrier

For bay type structures of semiconductor wafer transport systems, a configuration includes interbay rail tracks and intrabay rail tracks mounted on each other, vehicles of the interbay system and carrier transfer cars of the intrabay system moving freely bi-directional inside the bay area without obstructing each other. The carrier transfer car is configured such that a wafer carrier can be directly loaded from the vehicle to the load port of a processing machine. The configuration simplifies and accelerates the transfer and enhances the flexibility of vehicles in wafer transport.