Method and apparatus for monitoring the location of wafer disks

摘要

A method and system for monitoring the process of a plurality of batches of semiconductor wafers or memory disks through a series of processing operations. Each batch is placed in a carrier in which it is transported to the locations where the processing operations are performed. Each carrier is provided with a transponder tag coded to be responsive to within reading range of a reader unit which transmits a radio frequency signal to the transponder tag and reads and decodes a phase modulated signal returned by the transponder tag to uniquely identify the carrier that is positioned within range of the reader unit. Further control apparatus receives information from the reader units to permit the monitoring process of semiconductor wafer or memory disk batches through multiple processing operations.