首页   按字顺浏览 期刊浏览 卷期浏览 Electron Optical Investigation of Thin Films of Lithium on Tantalum, Platinum, and Carb...
Electron Optical Investigation of Thin Films of Lithium on Tantalum, Platinum, and Carbon Substrates

 

作者: A. L. Esquivel,   Ai‐Chun Fung,   H. U. Rhoads,   A. H. Weber,  

 

期刊: Journal of Applied Physics  (AIP Available online 1962)
卷期: Volume 33, issue 8  

页码: 2613-2618

 

ISSN:0021-8979

 

年代: 1962

 

DOI:10.1063/1.1729029

 

出版商: AIP

 

数据来源: AIP

 

摘要:

Thin films of lithium when evaporated onto well‐polished, chemically cleaned, and outgassed Ta and Pt substrates formed uniformly thick layers (in the range 240–1600 Å) suitable for thep‐nreaction in the Van de Graaff generator. A thin carbon coating, (about 300 Å thick) evaporated upon the Li film from a heated carbon filament immediately following the deposition of lithium on Ta and Pt substrates, insulated chemically the lithium from the air with its water vapor content and also provided carbon replicas of the Li films surface for electron microscopy.Proton bombardment of the carbon‐coated Li films had no visible effect on the carbon coating nor on the Ta or Pt substrate. However, after a proton beam bombardment of 10 &mgr;A‐min at 1.88 MeV, the Li films gave evidence of some initial damage effect (growth of grain size plus surface unevenness) which appeared to anneal away with subsequent bombardment.Orientation effects were observed in Li films deposited upon carbon substrates (in turn deposited on nickel lectromesh grids) in a special evaporator, attached to and forming a part of the vacuum system of the electron microscope (RCA type EMU‐2B) in order to avoid contamination of the Li with the laboratory atmosphere. Electron diffraction patterns revealed the following: (1) random orientation for the thinner (240 Å, approximately) Li films and (2) preferred orientation of the (110) and (200) planes nearly perpendicular to the surface for the thicker (1600 Å, approximately) films.

 

点击下载:  PDF (659KB)



返 回