POINT SPREAD FUNCTION ESTIMATION OF ELCTROMAGNETIC LENS SYSTEM ON SCANNING ELECTRON MICROSCOPE

• Main Author: Octariawan Fauzan, Muchamad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/39701
• Institution: Institut Teknologi Bandung

Scanning Electron Microscope (SEM) is an instrument that used to observe the surface of an object up to nanometer scale. Image degradation limits the process of observation and quantification of an object structural detail based on its SEM image. Improving the image quality by upgrading the hardware of SEM instrument is difficult and expensive. Therefore, computational imaging are being developed to overcome image degradation problems. One of the solutions that can be used to restore image quality is using deconvolution method. But it is necessary to determine the Point Spread Function (PSF) of SEM to apply the deconvolution method. The obective of this research is to investigate method to estimate the PSF of SEM Hitachi SU3500 which is located at PPNN ITB. Simulation and SEM observation images are being used for PSF estimation process. The proposed PSF estimation methods are using denoising and nonlinear regression on computational imaging. The estimated PSFs are normalized and compared with simulated PSF to obtain the mean squared error (MSE) value for quantitative evaluation. PSFs are also evaluated qualitatively by deblurring SEM images using Wiener filter and Richardson-Lucy (RL) deconvolution. The obtained MSE value is 6.349 × 10-3, showing that the proposed estimation PSF method produces an accurate estimated PSF and can be used to improve the quality of SEM images. The result for qualitative evaluation is that deconvolved images are succesfully deblurred. This shows that the estimated PSF method can be used to estimate the PSF of SEM Hitachi SU3500 to restore the quality of SEM images.