An environmental cell transmission electron microscope

Abstract
An aperture‐limited, differentially pumped environmental cell has been developed and installed in a JEOL 4000 EX electron microscope. With this environmental cell it is possible to observe, at high spatial resolution, the detailed changes in microstructure that occur during the interaction between a solid and a gaseous environment. The cell has been pressurized to 70 Torr with H2 gas for several hours with no adverse effects on the microscope performance. While the initial tests have been performed with hydrogen gas, the materials used to construct the environmental cell can tolerate corrosive environments. The key features of the environmental cell design along with the results from some applications are presented in this paper.