Research of values of distortions of digital SEM images obtained on SEM DSM-960A (CARL Zeiss, Germany) and the accuracy of their consideration

For measurements of digital SEM images of test grid with a resolution 1425 lin/mm taken on a digital SEM DSM-960A (Carl Zeiss, Germany), are defined by their scale and geometric distortion of the SEM magnification range from 1000h to 20000h. Found that the large-scale distortions of digital SEM images obtained in this type of SEM is systematic, regardless of the increase and is approximately -2 % along the x-axis image and -4 % along the y-axis with a picture. The geometrical distortion SEM images are significant, increase with increasing scale, as is systematic and can be considered by polynomial approximation.

Purpose. To investigate the magnitude and nature of the geometric distortion of digital SEM images obtained on SEM DSM-960A (CARL ZEISS) increases in the range of 1000h to 20000h and the effectiveness of their account by polynomial approximation. Methodology. The applied method of establishing geometric distortion of digital SEM images by measuring reference images of test objects to resolutions r = 1425 lin/mm, r = 3530 lin/mm using the program «Test-Measuring» and «Polycalc» PP «Dimicros". Results. The first time the study of metric quantities and nature of the geometric distortion of digital SEM images obtained on SEM DSM-960A (CARL ZEISS). Set to:a) increase (scale) digital SEM images obtained on SEM DSM-960A (CARL ZEISS) exposed to systematic distortions throughout the operating range of the microscope magnifications of up to 1000h 20000h. In particular, along the x-axis of the image they deviate from the prescribed values on the scale of REM on average - 2.2%, and along the y-axis of the image, by an average of -4.5%. They also tend to increase with increasing values increase, so they must be taken into consideration; b) digital SEM images obtained on SEM DSM-960A (CARL ZEISS) significant inherent geometric distortions, particularly in the size of digital image-REM 211.60 mm x 158.70 mm (800 x 600 pixels), they reach at its edges to ± 3 mm from the middle of the photograph; c) confirmed the effectiveness of polynomial approximation of geometric distortion of digital images that allow them to reduce the order; d) SEM DSM-960A (CARL ZEISS) can be considered stable working relation with metric device that still require periodic calibration to SEM-doffer prototypes using special test facilities. Scientific novelty. The study of geometric distortion of digital SEM images obtained on SEM DSM-960A (CARL ZEISS) in a wide range of parameters SEM-removal performed first. In studies used modern methods of processing the SEM images using the program «Test-Measuring» and «Polycalc» PP «Dimicros». The practical significance. The methodology used and the results can not only establish the size and nature of the geometric distortion of digital SEM images that they are inherent, but also effectively take them into account, and thus, improve the accuracy of obtaining quantitative parameters mikropoverhon are investigated using SEM.