TWO-DIMENSIONAL DISPLACEMENT MEASUREMENT USING THE SIX-POINT ATOMIC ENCODER TECHNIQUE

摘要

Since rapid progresses in nanotechnology and ultra precision engineering, several research activities and applications in fabrication process and metrology require an accuracy of sub-nanometer or less. For example, the precision X-Y stage used in the semiconductor lithography needs to be positioned and controlled accurately. A measurement of the two-dimensional (2-D) displacement is important for evaluating the stage's performance and the feedback control. In the previous research, the 2-D displacement measurement technique with 10-picometer resolution using a combination of the scanning tunneling microscope (STM) and the highly oriented pyrolytic graphite (HOPG) crystal was proposed.