WAFER PROBER

PURPOSE:To detect it for the contact resistance of the probe pins and the bonding pad to augment before any trouble happens and to prevent the trouble from generating by a method wherein a mechanism to polish the points of the probe points and a mechanism to measure the contact resistance of the points of the probe pins and the mechanism are provided. CONSTITUTION:A polishing plate 3 to polish the points of probe pins 2 and a contact plate 4 to measure the contact resistance of the probe pins 2 and the contact plate 4 are installed on a stage 1. When an inspection of wafer 7 is carried out using an IC tester 5, the polishing plate 3 is made to simultaneously shift periodically just under the probe pin 2 by making the stage 1 ascend and the point of the probe pin 2 is brought into a contact to the polishing plate 4 while the polishing plate 4 is made to move vertically to the vertical direction to clean the point of the probe pin. After that, the aluminum plate 4 is made to shift just under the probe pin, the stage 1 is made to ascend in the same manner, the probe pin 2 is brought into contact to the contact plate 4 and the contact resistance is measured by the IC tester 5. When the contact resistance is a certain resistivity set in advance or less, the inspection of wafer 7 is continued, but when the contact resistance is more than the certain resistivity, the inspection is stopped. By this way, an augmentation of the contact resistance due to contamination on the point of the probe pin can be detected. Moreover, it can be prevented that non-defective chips are misrecognized as the defective by defective probe pins and a reduction in the manufacturing yield of chip is brought.