Scanning Electron Microscopy Analysis of Thin Films: A Review

Thin films could be used in solar cell, laser devices, optical waveguides, optoelectronic devices and temperature sensors. These films were deposited using various methods such as sputtering, chemical bath deposition method, electro deposition method, pulsed laser deposition, vacuum evaporation, thermal evaporation, spray pyrolysis, e-beam evaporation, chemical vapor deposition and spin coating method. Characterization of the obtained films could be studied through x-ray photoelectron spectroscopy, x-ray diffraction, Raman spectrometry, Rutherford Backscattering spectrometry, atomic force microscopy, UV-Visible spectroscopy, transmission electron microscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis. The SEM technique could produce images by scanning the surface of the samples with focused electron beam. These electrons must interact with atoms (in the prepared films), produce different signals, contained very important information such as surface topography and composition. The SEM could reach resolution better than 1 nanometer, and the specimens could be detected in different environments (high vacuum, low vacuum or wet conditions). In this work, the morphological of the prepared films was reported based on the selected literature review. It was shown that grain size, thickness and grain shape strongly depended on the specific conditions.