| 摘要 |
PURPOSE:To reduce a detection error of positioning mark for electron beam exposure by a method wherein the position of the center of a mark to be detected is transferred to the neighborhood of the origin of the electron beam scanning system, and the position thereof is detected. CONSTITUTION:An arm 3a of mark in the Y direction is scanned in the X direction at the partial positions X1...Xn, reflected electrons are detected and stored, the feedback straight line A in the Y direction is calculated, the feedback straight line B is calculated in the same way to obtain the coordinate of the central point P (x1, y1) of the mark from the intersection (electron beam scanning system coordinate), those are reduced to the measured value x0, y0, and the coordinate x0+x1, y0+y1 of the point P are detected. When the electron beam scanning system coordinate is rotated at an angle theta in relation to the length measurement system coordinate, the more the scanning system coordinate (x'1, y'5) of the point P is remote, the more the error according to the angle theta of the length measurement system coordinate (x1, y1) is increased. Therefore when the center P of the mark is transferred to the neighborhood of the origin of the beam scanning system coordinate and the position thereof is detected, detection error of the central position P can be reduced even when the beam scanning system is rotating by regulation. |
