Development of an environmental TEM and its applications

Abstract

For the characterization of the materials under a wide range of different ambient atmospheres and temperatures, we have developed an environmental TEM based on a 300 kV TEM, which employs high resolution objective lens. The microscope column is differentially pumped using three sets of high speed turbo molecular pumps with a pumping speed of 260 l/s. In order to improve the experimental capability of the environmental TEM, we have developed an environmental cell. The developed environmental cell is a side entry type with a built-in specimen heater of a spirally shaped tungsten wire, which is used as the standard heater for high temperature specimen heating in principle. The developed holder is possible to use in the high resolution objective lens pole-piece. The gas pressure inside the environmental cell can be continuously controlled from 10-5 Pa to atmospheric pressure in the normally evacuated specimen chamber.