| 摘要 |
The wafer probe station includes: a plurality of the pressure sensors; a tilt correction unit which is constructed with a plurality of actuators, a plurality of displacement sensors which are disposed at positions adjacent to the corresponding actuators and a microcomputer; and a control unit which allows the wafer to be come in contact with the probe card by lifting up a Z-axis stage by a predetermined overdriving amount, extracts the pressure values of the installation positions from the pressure sensors, calculates driving amounts of the actuators of the tilt correction unit by using the pressure values so that a uniform load is applied to the chuck, calculates X and Y directional displacement values w occurring according to a change in a tilt of the chuck, lifts down the Z-axis stage, and after that, corrects an eccentric load of the chuck by driving the actuators of the tilt correction unit according to the driving amounts, and controls movement of the XY-axis stage by using the X and Y directional displacement values w. Accordingly, it is possible to accurately sense an eccentric load occurring at the time of performing the overdriving, and it is possible to rapidly and accurately perform initial setting for the eccentric load by adjusting a tilt of the chuck, so that it is possible to reduce a read time of a testing process. |
