A study of the 'total voltage' effect

An electron spectroscopy technique, employing a plane-parallel electrode geometry with an anode probe hole has been used to make a detailed study of how the Fowler-Nordheim plot of a single emission site varies with gap separation d. After correction for the gap field in the vicinity of the probe hole, it has been established that the field enhancement or beta factor of the site does not in fact exhibit a dependence on the total gap voltage over the range 0.4>