Surface characterization studies on chemically vapor deposited tungsten

Surface characterization studies were performed on chemically vapor deposited (CVD) tungsten. Two specimens of tungsten were taken from each of three sample lots and prepared with standard cleaning and firing procedures and then electropolished. In order to evaluate the effect of grain size, one set of specimens was given an additional vacuum firing at 2500°C to promote grain growth. Surfaces of tungsten were characterized by Auger analysis, X-ray diffraction analysis, etch pit analysis, and low energy electron diffraction (LEED) analysis. A description of the various methods along with the results are presented.