STUDY OF ELECTRICAL AND PHYSICAL CHARACTERISTICS OF SECONDARY EMITTING SURFACES
Abstract
Vacuum techniques used in this laboratory are described as well as the methods used to measure secondary electron yields, to heat small parts in a vacuum and to clean surfaces by ion bombardment. Studies of the variation of secondary yield with angle of incidence of the primary beam are described for metal and for semiconducting crystals. In the case of titanium, the influence of such factors as primary energy, orientation of the crystals, heat treatment and exposure to gas are discussed. Similar results for tungsten and germanium are compared with the case of titanium. Measurements of the transmission and reflection secondary yield of an unbacked MgO film are presented. An experiment is described which shows that the color produced in MgO by electron bombardment extends throughout the whole crystal. Studies of the influence of a cesium overlayer on the secondary yield of MgO films are reported, with particular reference to the stability of the yield under electron bombardment. The effect of exposing such films to the atmosphere is also described. The results of an investigation of the optimum oxidation conditions for Mg-Ag alloy are presented. The thickness required for full unenchanced yield is given as well as the dependence of the enhancement effect on thickness. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1962
- Accession Number
- AD0290640
Entities
People
- W.t. Peria
Organizations
- University of Minnesota