Patent · US Expired

Method of manufacturing a thermionic cathode and thermionic cathode manufactured by means of said method

US4533852A · kind A · utility

18Cited by

5References

30Claims

0Family size

Assignee

U.S. Philips Corporation · US

Inventors

Berthold Frank · Aachen, DE
Georg Gartner · Aachen, DE
Hans Lydtin · Stolberg, DE

Key dates

Filing date	Dec 6, 1982
Grant date	Aug 6, 1985
Priority date	—
Expiry date	Dec 6, 2002

Classification

Technology area (CPC H)Electricity
CPC primaryH01J1/14
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

The cathode (4) the material of which is substantially high-melting metal such as W, Mo, Ta, Nb, Re and/or C, consists of a very fine-grained mechanically stable support layer (5), a series of layers (6) considerably enriched with emissive material, in general from the scandium group especially from the group of rare earth metals, preferably with Th or compounds thereof and a thermally stable preferentially oriented coating layer (7). All the layers are provided via the gaseous phase, for example, CVD methods, on a substrate (1) formed according to the desired cathode geometry. The substrate (1) is removed after termination of the deposition. FIG. 2.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.