Accession Number : ADD012838

Title :   Thermionic Cathode Coating by OMCVD (Organo-Metallic Chemical Vapor Deposition).

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Berry,Alan D ; Shih,Arnold S ; Haas,George ; Marrian,Christian ; Hor,Charles

Report Date : 24 Mar 1987

Pagination or Media Count : 15

Abstract : The present invention relates to a new and improved thermionic cathode and, more particularly, to a thermionic cathode having a novel coating thereon and to the method of forming the coating. High power electron tube devices, such as travelling wave tubes and other microwave generators, require electron emitters or cathodes having very high electron emission densities. For example, emission densities of approximately 15 Amperes/2 sq. cm. and greater are required. Failure of the cathode of a tube always results in tube failure. Since cathodes cannot be replaced without rebuilding the entire tube, early failure of a tube's cathode can be a costly event. In many tubes, lifetimes of tens of thousands or more hours must be achieved in order for the tube to an economically viable device.

Descriptors :   *PATENT APPLICATIONS, *CATHODES, *COATINGS, *VAPOR DEPOSITION, CHEMICAL REACTIONS, DENSITY, ELECTRON EMISSION, EMISSION, FAILURE, MICROWAVE EQUIPMENT, ORGANOMETALLIC COMPOUNDS, RADIOFREQUENCY GENERATORS, THERMIONIC EMISSION, TRAVELING WAVE TUBES, VIABILITY

Subject Categories : Coatings, Colorants and Finishes

Distribution Statement : APPROVED FOR PUBLIC RELEASE