Patent ID: 8441618

Claim:
A method of transferring a substrate between a first module and a second module using a substrate transfer apparatus, wherein, in plan view, the first and second modules both face a transfer path, the transfer path extends substantially linearly in a Y-direction, and the second module is located on an imaginary extension in the Y-direction of the transfer path, and wherein the substrate transfer apparatus includes: a moving base having a horizontal, Y-motion axis for moving the moving base in the Y-direction; and a substrate holding member mounted to the moving base via a horizontal, X-motion axis so as to move relative to the moving base to be in an advanced position and a retracted position relative to the moving base, via a θ-motion axis so as to turn about a vertical axis relative to the moving base, and via a Z-motion axis so at to move vertically relative to the moving base, said method comprising: transferring a substrate from the first module to the substrate holding member; moving the moving base toward the second module by operating the Y-motion axis; advancing the substrate holding member relative to the moving base by operating the X-motion axis, in order to place the holding member in the advanced position; and turning the substrate holding member by operating the θ-motion axis to direct the X-motion axis in the Y-direction so as to orient the substrate holding member toward the second module if the first module and the second module are oriented to different directions; vertically moving the substrate holding member by operating the Z-motion axis to position the substrate holding member at a level of the second module, if the first module and the second module are located at different levels; judging whether a Y-motion axis operating time is longer than a longer one of a θ-motion axis operating time and a Z-motion axis operating time; wherein if the Y-motion axis operating time is judged to be longer than the longer one of the θ-motion axis operating time and the Z-motion axis operating time, initiating the advancing of the substrate holding member by the X-motion axis upon completion of an operation of one of the θ-motion axis or the Z-motion axis having the longer operating time so that the X-motion axis operating time overlaps with the Y-motion axis operating time, and if the Y-motion axis operating time is judged to be not longer than the longer one of the θ-motion axis operating time and the Z-motion axis operating time, initiating the advancing of the substrate holding member by the X-motion axis after completion of an operation of the Y-motion axis so that the X-motion axis operating time does not overlap with the Y-motion axis operating time, and transferring the substrate from the substrate holding member placed in the advanced position to the second module with the X-motion axis and the Y-motion axis being parallel with each other.