Observation of Slow States on Germanium Surface by Tunneling at d‐c Field Effect

The internal electron field emission from the oxide trap states located on the surface of germanium is measured by means of the d‐c field effect. The electrons are tunneling into the bulk material where they are accumulated. The emission of electrons is detectable for negative field strength F greater than a critical value F*. The experimental results obtained from this investigation, of the so‐called storage effect, are in good agreement with the results obtained using the a‐c field effect. By measuring the field F*, which is characteristic of the surface state, the energy of the states can be investigated. It is deduced from kinetic observations that the emission centres and the so‐called slow states are identical. Hence informations about the slow states may be obtained by investigating the storage effect.