Abstract：In order to obtain the specific characteristics of dimensional metrology of nano-scale critical dimension, an approach probing strategy of critical dimension dimension measurement is proposed by using auto-focus laser sensor. Both one-dimensional precision displacement platform (X axis) and auto-focus laser sensor (Z axis) are used to build the measurement platform. The integrated circuit board is used as the test model, and the test model is fixed on the displacement platform, so that it can only move along the X axis. Then laser sensor perpendicularly is used to scan the outline of a scribed critical dimension line, and the data of X axis and Y axis is collect meanwhile. At last, the mathematical model is established. The experimental data is dealed by using piecewise linear fitting of the least squares method, and the line width and higher parameters as so on is obtained. In order to verify the reliability and accuracy, contacted nano-scale inductive sensor is used as contrast test experiment. The same surface topography data is collected, and the final results are obtained by using the same mathematical methods. Finally, the accuracy and feasibility of the experiment is verified by the comparing experimental results.
2014, Vol. 35 
