Recently, a research team from the Shanghai Institute of Optics and Fine Mechanics, part of the Chinese Academy of Sciences, has achieved significant advancements in the precise characterization of nanofilms through transmission electron microscopy (TEM). The team has developed a novel formula to calculate film thickness when the sample is tilted along the β direction. Additionally, they have introduced a method for accurately characterizing the structure of nanofilms using TEM. This innovative approach involves initially slicing the Si wafer along a predetermined direction during sample preparation. Subsequently, the sample is observed from a specific zone axis to ensure that its cross-section remains perpendicular to the electron beam. This orientation facilitates photographic analysis in the thinner regions of the sample, enhancing the precision and reliability of the results.