| 摘要 |
PURPOSE:To perform alignment with high accuracy in an automatic mask aligning device, by causing a computer to process a signal showing the relative position of a mask and a wafer and control motors for moving the wafer or the mask depending on their relative position. CONSTITUTION:The position of a target on a wafer and that of another target on a mask are detected by photoelectric converters or the like. A mask aligner 61 supplies a necessary signal to a computer 64 to perform calculation. The result of the calculation is applied to a piezoelectric inching mechanism to drive piezoelectric minute- step motors 681, 682, 683 for variables x, y, theta through the motor controllers 671, 672, 673 of the inching mechanism to displace the wafer or the mask. The relative position of the mask and the wafer is detected to rapidly drive the piezoelectric motors toward an objective position. When the motors have passed through the objective position, they are slowly reversed to set the water or the maks in the objective position. The mask is thus aligned with high accuracy. |
