Collation method of stocker storage in semiconductor wafer cassette transportation apparatus

A collation method of stocker storage employed in a semiconductor wafer cassette transportation apparatus including

• a stocker for storing a plurality of semiconductor wafer cassettes,
• a processing apparatus for applying a process on said semiconductor wafer cassette,
• an automatic carrier for carrying out a transportation task of said semiconductor wafer cassette between said stocker and said processing apparatus,
• an inter-stocker transport device for carrying out a transportation task of said semiconductor wafer cassette between a source stocker and a destination stocker, and
• a host computer for providing control of said stocker, said inter-stocker transport device, said automatic carrier and said processing apparatus,
• said host computer including
• a terminal for transmitting an instruction from an operator to said host computer, and providing a display of a result, and
• stocker storage memory means for storing storage information of a stocker,
• said collation method of stocker storage comprising the steps of:
• interrogating about storage of said semiconductor wafer cassette in said stocker in response to an instruction from an operator,
• receiving storage information of said semiconductor wafer cassette from said stocker,
• comparing the storage information sent from said stocker with the storage information of said stocker stored in said stocker storage memory means, and
• when the storage information retained by said stocker differs from the storage information of said stocker stored in said stocker storage memory means, providing a display on said terminal of discrepancy in storage information.