Thickness Estimation of Carbon Films by Electron Microscopy of Transverse Sections and Optical Density Measurements

Abstract
A rapid and convenient method is described for the accurate determination of the thickness of carbon films from their optical density. A linear relationship was found between optical density and film thickness. The optical‐density‐thickness curve was calibrated by direct measurement of the thickness of transverse sections of carbon films embedded in epoxy resin. The method can probably be extended to thin films of soft metals and other inorganic films having significant optical density and capable of being sectioned with a diamond knife.