FIELD-EMISSION FROM MICROSTRUCTURED CESIATED SURFACES

A comparative analysis of three experiments on held electron emission from microstructured cesiated surfaces is presented. In this context, the term ''cesiated surface'' implies generally any coverage of cesium on a metallic substrate, while the term ''microstructure'' includes t he intrinsic microstructure of any solid substrate as well as the indu ced microstructure of the liquid cesium coverage due to electrohydrody namic effects. These experiments concern a thin-film held-emission mic rocathode, a single pin-and-tube-type liquid metal electron source, an d a large-area microstructured liquid metal electron source. The elect ron sources are compared by their emission characteristics and the res ulting Fowler-Nordheim plots. The existence of both a stable and unsta ble field-emission mode from microstructured cesiated surfaces had bee n proven. Whether the first mode is of importance to vacuum microelect ronics is a question which needs further investigation; the second mod e seems to be of importance for regenerative and indestructible field electron sources with possible applications in pulsed power technology . (C) 1996 American Vacuum Society.