PURPOSE: To position electron beams by a method wherein the upper section of a sample is irradiated with electron beams, moving a base plate, the sample pattern information of a secondary electron signal is obtained, the base plate is shifted, numbers where electron beams cross a metallic wiring are acquired, and collated with design information and a current irradiation position is obtained.
CONSTITUTION: A sample 6 on an X-Y stage 5 is irradiated with electron beams 4, and a secondary electron signal 7 generated reaches a detector 9 through a grid 8. The stage 5 is controlled 11 by a pulse motor 10, and driven. The detecting output 9 is processed 9, and inputted to a pattern detector 13. The number of metallic wirings and wiring width are detected by a detector 13 while the variation of the quantity of the secondary electron signal is collated with design information by using an output from a design-information storage means 14, thus determining the current position of beams. A signal displaying the speed of travel of the stage is transmitted over the pattern detector 13 from the device 11, and a distance up to the present address from an initial position is determined from the time and speed information. The command of movement of the stage is sent to the controller 11 from the detector 13, and a position on the desired sample 6 can be irradiated with beams.
ITO AKIO
FURUKAWA YASUO
OZAKI KAZUYUKI
ISHIZUKA TOSHIHIRO
OKUBO KAZUO
