| 摘要 |
PURPOSE:To improve precision in a pattern drawing process by a method wherein a means is provided for detecting the quantity of vertical displacement (height) and a transporting means or a deflector is controlled according to the output yielded by a deviation determining means when the beam illuminates the position of drawing. CONSTITUTION:Prior to pattern drawing, beam axis deviation alpha (beta) in the direction vertical to the reference surface of the material to be worked on is determined. Measurement follows for the height (h) whereat pattern drawing is performed on the material. A CPU5 determines the quantities -h tan alpha and -h tan beta required to correct the deviation of the beam axis in a direction vertical to the reference surface of the material. Signals incorporating the correcting quantities are supplied to a motor regulating circuit 8 via a D/A converter 7 for a two-dimensional displacement of a stage 2 corresponding to the inputted correcting quantities. As the result, the beam can be illuminated upon a prescribed position for pattern drawing. |
