Pixel length calibration using a pattern matching method for secondary-electron images

We developed a calibration method using a pattern matching method for the SEM equipped with laser interferometer units at an X-Y sample stage. By comparing two images captured before and after the stage movement, an each of moving pixel number to X and Y direction were analyzed using the image processing technique. Then the pixel length was calibrated using stage position data and the pixel data. The developed calibration methods were applied to nano-particle measurements. The sample particle sizes were nominal diameter of 100 nm and 300 nm. Measurement uncertainty evaluation was done and quantitatively reliable results were obtained.