Accession Number : AD0487531

Title :   CHEMICAL VAPOR DEPOSITED MATERIALS FOR ELECTRON TUBES.

Descriptive Note : Quarterly rept. no. 4, 15 Feb-14 May 66,

Corporate Author : RAYTHEON CO WALTHAM MA RESEARCH DIV

Personal Author(s) : Steele, S. R. ; Pappis, J. ; Hagen, L. ; Schilling, H.

Report Date : JUL 1966

Pagination or Media Count : 62

Abstract : This program was established to investigate chemical vapor deposition as a method of producing materials or coatings for use in vacuum electron devices and microwave tubes. CVD TiB2, which may be used as a secondary emission inhibitor, has been deposited on isotropic CVD BN, and graphite. CVD ZrC has been deposited strongly preferred in the (100) orientation, and its thermionic work function has been measured. CVD tungsten coatings have been made upon isotropic CVD BN. Some difficulties have been encountered in bonding. Experiments have been continued with two methods of preparing CVD BN, as well as CVD Si2N4, and co-deposited BN with Si3N4. The thermal conductivity of isotropic CVD BN is approximately the same as dense beryllia between 300 and 900 C in spite of its much lower density. The electrical conductivity of CVD silicon nitride and anisotropic CVD BN has been measured as a function of temperature. Isotropic CVD BN has been deposited in configurations similar to those used for microwave windows. Isotropic CVD BN appears to be very promising for high power window applications. (Author)

Descriptors :   (*VAPOR PLATING, ELECTRON TUBES), (*REFRACTORY COATINGS, VAPOR PLATING), COATINGS, MATERIALS, CARBIDES, BORIDES, TUNGSTEN, THERMIONIC EMISSION, MICROWAVE EQUIPMENT.

Subject Categories : Electrical and Electronic Equipment
      Ceramics, Refractories and Glass
      Coatings, Colorants and Finishes

Distribution Statement : APPROVED FOR PUBLIC RELEASE