APPLIED RESEARCH ON FIELD EMISSION CATHODES.
Abstract
Effort was directed toward the study of field emission cathodes and their development to a practical electron source. Primary emphasis was on relatively gross structures for use at high power levels. Emission currents to 22 amperes at 390 kilovolts were obtained from single, needle-shaped, tungsten emitters and to 105 amperes at 203 kilovolts from an edge-shaped, tungsten structure. Point cathodes were shown to emit maximum currents in agreement with theoretical prediction based on energy exchange at the cathode and on cathode dimensions. Electrolytic and chemical techniques were developed for fabrication of edge cathodes which were free of cold work and had terminal radii of the order of 0.00001 cm. Electron optical systems appropriate for use with field emitted beams were studied; and basic knowledge of the behavior of adsorbates which improve beam utility by selective emission enhancement in the forward direction was extended. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 15, 1964
- Accession Number
- AD0449658
Entities
People
- E. E. Martin
- F. M. Charbonnier