| 摘要 |
PURPOSE: An apparatus for automatically aligning a semiconductor wafer to measure overlay is provided to eliminate the need for an operator to collect the wafer when a prealignment fails and to reduce a downtime, by automatically adjusting the position of the wafer by a value of a distance between a mark formed in an edge of the wafer and a mark of a wafer alignment apparatus before an overlay of the patterned wafer is measured. CONSTITUTION: An apparatus for automatically aligning a semiconductor wafer(20) comprises a light emitting element(100), a light receiving element(110), a control element(120), an adjustment motor(140) and a motor driving element(130). The light emitting element irradiates light to the wafer, positioned on the front surface of the wafer. The light receiving element receives the light penetrating the wafer and converts the received light to an electrical signal, positioned on the rear surface of the wafer. The control element calculates how much the position of the wafer deviates by using the electrical signal supplied from the light receiving element, and supplies a motor driving control signal for adjusting the position of the wafer according to the calculation. The adjustment motor adjusts the position of the wafer. The motor driving element drives the adjustment motor in response to the motor driving control signal supplied from the control element to adjust the position of the wafer. |
