Standards Development

Scope

This document specifies procedures for the measurement of the foil thickness of the specimen by a combination of (scanning) transmission electron microscope (STEM/TEM) and electron energy-loss spectroscopy (EELS).

This document applies to measuring the foil thickness less than the thickness of electron transparency. Accurate measurement of thin foil thickness is paramount for STEM/TEM characterization of materials, and several methods have been proposed. Among them, EELS is a representative method because, unlike other methods, it can be applied regardless of the state of the material. Low-loss spectra including zero-loss and plasmon peaks are used for the measurement.

Purpose

Electron microscope is a frequently used instrument to acquire not only high-resolution images but also great numbers of sample information such as structural and compositional information. Due to the necessity of transmitted electrons, (S)TEM specimens must be prepared as thin as possible so that to let the sample to be electron transparent, and the foil thickness is the vital information of the (S)TEM samples. It is therefore highly required to standardize certain aspects of the technique at an international level and establish an international standard serving as a basis for facilitating the easier use of the foil thickness measurement by the users of (S)TEM.