| 摘要 |
PURPOSE:To match the error trends of steppers therebetween, and to reduce the deviation of positions by disposing many position deviation detecting patterns in one shot to detect the intrinsic errors of the steppers, and correcting the errors. CONSTITUTION:A polysilicon layer 11 corresponding to the same first reference pattern 4 remains in 25 zones in a chip 2 within one shot by etching in a state that a thin oxide film 10 and the layer 11 adheres to the surface of a semiconductor wafer 1. Then, other stepper is employed to form a second position deviation detecting pattern 5 in the same zone. Thereafter, positional deviations (x), (y) are actually measured, decomposed into a rotary error, a magnification error and a residual error, and the rotary error and the magnification error are corrected. Thus, the intrinsic error of the stepper is reduced to the residual error thereby to perform a mask alignment of extremely high accuracy. |
