Accession Number : AD0644697

Title :   CONDENSATION AND NUCLEATION PROCESSES OF SINGLE CRYSTAL THIN FILMS.

Descriptive Note : Summary technical rept., 1 Jul 65-10 Jun 66,

Corporate Author : HUGHES RESEARCH LABS MALIBU CALIF

Personal Author(s) : Kikuchi,Ryoichi ; Kaspaul,Alfred F. ; Braunstein,Morris ; Kaspaul,Erika E. ; McKee,W. E.

Report Date : OCT 1966

Pagination or Media Count : 260

Abstract : The purpose of the contract was to conduct a basic research investigation of the condensation and nucleation processes controlling the formation of single crystal thin films on crystalline and amorphous dielectric substrates. In the theoretical analysis, a new technique called the path probability method (of irreversible cooperative processes) was used to derive a set of kinetic differential equations to describe nucleation and film growth. The existence of the discontinuous condensation temperature was derived, and the size of critical nuclei deduced. The influence of predeposited foreign atoms on nucleation was studied. This theoretical technique is expected to derive more detailed information of the film growth processes. The moving mask experiment grows a silicon film by vapor deposition, starting with a single, small cluster of silicon at the apex of the mask opening. Further unwanted nucleation is prevented by the mask, and the slit opening can adjust the thickness of the film. Experiments conducted so far indicate that the moving mask technique promises to produce better single crystal films than those produced by existing methods. In another experimental project, the influence of predeposited foregin atoms on nucleation and film growth was studied. Using thermal dissociation of silane on a sapphire substrate, it was found that predeposited nickel, chrome, and Nichrome-V alloy enhance nucleation of silicon. This finding is in general agreement with the results of the theoretical study. (Author)

Descriptors :   (*FILMS, *SINGLE CRYSTALS), (*CONDENSATION, FILMS), (*NUCLEATION, FILMS), SEMICONDUCTING FILMS, SILICON, STATISTICAL MECHANICS, IRREVERSIBLE PROCESSES, SUBSTRATES, DIELECTRICS, CRYSTAL GROWTH, VAPOR PLATING

Subject Categories : Physical Chemistry
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE