SYSTEM FOR TESTING WAFER AND ITS AUTOMATIC CALIBRATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a high-speed and low-cost system for testing wafers and its automatic calibration system. ;SOLUTION: In an instrumentation station 118, a wafer 124 is rotated in its vertical plane and a scanning sensor is moved linearly along a parallel axis with the rotational plane of the wafer 124 to obtain thereby spiral and other scanning paths of the wafer 124 over its whole surface. By holding the wafer 124 vertically in this way, the errors caused by the originating deflection from the weight of the wafer itself, especially the large wafer (e.g. 300mm in diameter), are reduced. Further, in the instrumentation station 118, providing a plurality of wafer grippers, they are moved in the plane of the wafer 124 to fasten it to the grippers in predetermined places for its rotation. Also, in the instrumentation station 118, a plurality of master calibration gauges 212 are provided to simplify thereby the calibration of the testing system for wafers, making any wafer for calibration tests unnecessary. Digitizing early the obtained probe instrumentation data of the wafer 124, they are calibrated thereafter in a digital way to decode them again and perform their filterings and other processings.;COPYRIGHT: (C)1998,JPO