Observations of the behaviour of some thin film cathodes in the scanning electron microscope

The tope electrodes of silver or copper from which electron emission occurs, are studied for M-I-M structures of AgSiO/B₂]O₃Cu and AgSiO/B₂O₃Ag while the specimens are contained in the chamber of a scanning electron microscope and subjected to bias voltages. Electroforming of the samples and their subsequent operation as negative resistance and electron-emitting devices lead to characteristic disturbances of the top electrodes which are consistent with the idea of filamentary conduction processes.