Crystal structure of the metal postbreakdown droplets on a nanometric or atomic scale

摘要

The formation of microprotrusions with droplets as a result of vacuum breakdown on a metal field emitter is well known. These microprotrusions can grow during solidification of a liquid molten phase both on the cathode and on anode. Results of field emission microscopy investigation of the surface of postbreakdown droplets (both on cathode and anode) are summarized and analysed. Taking into account very high rates of cooling of the material at and directly after droplet formation the observed properties of the droplets surfaces (and the bulk) can be explained as disordering and amorphization of their bulk structure and especially the parts near to the surface.