Other Adsorption Experiments with the Field Emission Microscope

Other Adsorption Experiments with the Field Emission Microscope 

When the point is at 600°K. while the tungsten is deposited, the atoms which strike the 211 plane migrate rapidly in the 111 direction and deposit themselves on the edges of the plane, where they form a crescent-shaped mound on the 110 plane they can move only short distances to form fairly large, brightly emitting crystallites on the 100 plane they can form only very small crystallites. 

If the tungsten is deposited on a TSO K. point, it can migrate and become deposited on the edges of the 211 and 110 planes but it still cannot migrate on the 100 plane. 

The Desorptim of Positive Hydrogen Ions by High Fields 

When the tungsten is heated to 400° to 500°K. while the applied field is between 200 to 300 million volts/cm., the pattern becomes less sharp, the emission spots appear to be agitated, and the 110 rings shrink toward the center. The proposed interpretation is that at these high fields the tungsten atoms can be pulled off the edges of planes even at 450°K. 

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VI. Other Adsorption Experiments with the Field Emission Microscope... 192... 

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